Sample records for routine bioassay programs

  1. Hanford Internal Dosimetry Program Manual, PNL-MA-552

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.

    2003-10-10

    This manual is a guide to the services provided by the Hanford Internal Dosimetry Program (IDP). It describes the roles of and relationships between the IDP and site contractors, and provides recommendations and guidance for consideration in implementing bioassay monitoring and internal dosimetry elements of radiation protection programs. Guidance includes identifying conditions under which workers should be placed on bioassay programs, types, descritptions, and capabilities of measurements, suggested routine bioassay programs, limitations on services, and practices for recording and reporting results.

  2. Technical basis for internal dosimetry at Hanford

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1991-07-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ({sup 58}Co, {sup 60}Co, {sup 54}Mn, and {sup 59}Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium,. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation and bioassay follow-up treatment. 78more » refs., 35 figs., 115 tabs.« less

  3. Technical basis for internal dosimetry at Hanford

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1989-04-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products (/sup 58/Co, /sup 60/Co, /sup 54/Mn, and /sup 59/Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation; and bioassay follow-up treatment. 64more » refs., 42 figs., 118 tabs.« less

  4. Jack Healy Remembers - Anecdotal Evidence for the Origin of the Approximate 24-hour Urine Sampling Protocol Used for Worker Bioassay Monitoring

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.

    2008-10-01

    The origin of the approximate 24-hour urine sampling protocol used at Hanford for routine bioassay is attributed to an informal study done in the mid-1940s. While the actual data were never published and have been lost, anecdotal recollections by staff involved in the initial bioassay program design and administration suggest that the sampling protocol had a solid scientific basis. Numerous alternate methods for normalizing partial day samples to represent a total 24-hour collection have since been proposed and used, but no one method is obviously preferred.

  5. Methods to improve routine bioassay monitoring for freshly separated, poorly transported plutonium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bihl, D.E.; Lynch, T.P.; Carbaugh, E.H.

    1988-09-01

    Several human cases involving inhalation of plutonium oxide at Hanford have shown clearance half-times from the lung that are much longer than the 500-day half-time recommended for class Y plutonium in Publication 30 of the International Commission on Radiological Protection(ICRP). The more tenaciously retained material is referred to as super class Y plutonium. The ability to detect super class Y plutonium by current routine bioassay measurements is shown to be poor. Pacific Northwest Laboratory staff involved in the Hanford Internal Dosimetry Program investigated four methods to se if improvements in routine monitoring of workers for fresh super class Y plutoniummore » are feasible. The methods were lung counting, urine sampling, fecal sampling, and use of diethylenetriaminepentaacetate (DTPA) to enhance urinary excretion. Use of DTPA was determined to be not feasible. Routine fecal sampling was found to be feasible but not recommended. Recommendations were made to improve the detection level for routine annual urinalysis and routine annual lung counting. 12 refs., 9 figs., 7 tabs.« less

  6. Determination of an environmental background level of 90Sr in urine for the Hanford bioassay program.

    PubMed

    Antonio, C L; Rivard, J W

    2009-11-01

    During the decommissioning and maintenance of some of the facilities at the U.S. Department of Energy Hanford Site in Washington State, workers have potential for a Sr intake. However, because of worldwide radioactive fallout, Sr is present in our environment and can be detectable in routine urine bioassay samples. It is important for the Hanford Site bioassay program to discriminate an occupational intake from a non-occupational environmental one. A detailed study of the background Sr in the urine of unexposed Hanford workers was performed. A survey of the Hanford Site bioassay database found 128 Hanford workers who were hired between 1997 and 2002 and who had a very low potential for an occupational exposure prior to the baseline strontium urinalysis. Each urinalysis sample represented excretion during an approximate 24-h period. The arithmetic mean value for the 128 pre-exposure baselines was 3.6 +/- 5.1 mBq d. The 99 percentile result was 17 mBq d, which was interpreted to mean that 1% of Hanford workers not occupationally exposed to strontium might exceed 17 mBq d.

  7. Determination of an Environmental Background Level of Sr-90 in Urine for the Hanford Bioassay Program Determination of an Environmental Background Level of Sr-90 in Urine for the Hanford Bioassay Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Antonio, Cheryl L.; Rivard, James W.

    2009-11-01

    During the decommissioning and maintenance of some of the facilities at the U.S. Department of Energy Hanford Site in Washington State, workers have potential for a 90Sr intake. However, because of worldwide radioactive fallout, 90Sr is present in our environment, and can be detectable in routine urine bioassay samples. It is important for the Hanford Site bioassay program to discern an occupational intake from a non-occupational environmental one. A detailed study of the background 90Sr in the urine of unexposed Hanford workers was performed. A survey of the Hanford Site bioassay database found 128 Hanford workers who were hired betweenmore » 1997 and 2002 and who had a very low potential for an occupational exposure prior to the baseline strontium urinalysis. Each urinalysis sample represented excretion during an approximate 24-hr period. The arithmetic mean value for the 128 pre-exposure baselines was 3.6 ± 5.1 mBq d-1. The 90Sr activities in urine varied from -12 to 20 mBq. The 99th percentile result was 16.4 mBqd-1, which was interpreted to mean that 1% of Hanford workers not occupationally exposed to strontium might exceed 16.4 mBq d-1.« less

  8. The relevance and use of mouse embryo bioassays for quality control in an assisted reproductive technology program.

    PubMed

    Scott, L F; Sundaram, S G; Smith, S

    1993-09-01

    To define both the limits of a mouse embryo bioassay for quality control in an assisted reproductive technology (ART) program and the areas where it can be effectively used. Embryos at the pronuclear and two-cell stage from three different strains of mice were used to assess the effectiveness of this assay for media quality control using five different media routinely used in ART. Pronuclear and two-cell embryos from CD-1 mice were used to test the ability of a mouse embryo bioassay to control for water quality, contaminants in the culture system, and fluctuations in the environmental conditions using a medium, culture system, and scoring technique that were optimized for this strain. The mouse embryo bioassay is not effective in differentiating media appropriate for supporting human embryo development since the development of mouse embryos in vitro is strain, stage, and media related. However, CD-1 embryos were shown to be sensitive to variations in water quality, pH, temperature, incubator conditions, and contaminants in the system when grown in a protein-free medium optimized for their development. Both total blastocyst number and the cell count in the blastocysts were affected. Pronuclear embryos were more sensitive to perturbations in the culture system than two-cell embryos. A mouse embryo bioassay can be effectively used as a means of quality control of water, chemicals, and contact materials and for technique standardization and training in an assisted reproduction program. All the conditions of the test should be defined, pronuclear embryos should be used, and the end point should be fully expanded blastocysts and/or cell numbers in these blastocysts where appropriate.

  9. [Investigation on pattern of quality control for Chinese materia medica based on famous-region drug and bioassay--the work reference].

    PubMed

    Yan, Dan; Xiao, Xiaohe

    2011-05-01

    Selection and standardization of the work reference are the technical issues to be faced with in the bioassay of Chinese materia medica. Taking the bioassay of Coptis chinensis. as an example, the manufacture process of the famous-region drugs extraction was explained from the aspects of original identification, routine examination, component analysis and bioassay. The common technologies were extracted, and the selection and standardization procedures of the work reference for the bioassay of Chinese materia medica were drawn up, so as to provide technical support for constructing a new mode and method of the quality control of Chinese materia medica based on the famous-region drugs and bioassay.

  10. Methods and Models of the Hanford Internal Dosimetry Program, PNNL-MA-860

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.

    2009-09-30

    The Hanford Internal Dosimetry Program (HIDP) provides internal dosimetry support services for operations at the Hanford Site. The HIDP is staffed and managed by the Radiation and Health Technology group, within the Pacific Northwest National Laboratory (PNNL). Operations supported by the HIDP include research and development, the decontamination and decommissioning of facilities formerly used to produce and purify plutonium, and waste management activities. Radioelements of particular interest are plutonium, uranium, americium, tritium, and the fission and activation product radionuclides 137Cs, 90Sr, and 60Co. This manual describes the technical basis for the design of the routine bioassay monitoring program and formore » assessment of internal dose. The purposes of the manual are as follows: • Provide assurance that the HIDP derives from a sound technical base. • Promote the consistency and continuity of routine program activities. • Provide a historical record. • Serve as a technical reference for radiation protection personnel. • Aid in identifying and planning for future needs.« less

  11. Use of probability analysis to establish routine bioassay screening levels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, E.H.; Sula, M.J.; McFadden, K.M.

    1990-09-01

    Probability analysis was used by the Hanford Internal Dosimetry Program to establish bioassay screening levels for tritium and uranium in urine. Background environmental levels of these two radionuclides are generally detectable by the highly sensitive urine analysis procedures routinely used at Hanford. Establishing screening levels requires balancing the impact of false detection with the consequence of potentially undetectable occupation dose. To establish the screening levels, tritium and uranium analyses were performed on urine samples collected from workers exposed only to environmental sources. All samples were collected at home using a simulated 12-hour protocol for tritium and a simulated 24-hour collectionmore » protocol for uranium. Results of the analyses of these samples were ranked according to tritium concentration or total sample uranium. The cumulative percentile was calculated and plotted using log-probability coordinates. Geometric means and screening levels corresponding to various percentiles were estimated by graphical interpolation and standard calculations. The potentially annual internal dose associated with a screening level was calculated. Screening levels were selected corresponding to the 99.9 percentile, implying that, on the average, 1 out of 1000 samples collected from an unexposed worker population would be expected to exceed the screening level. 4 refs., 2 figs.« less

  12. Standardization of a fluconazole bioassay and correlation of results with those obtained by high-pressure liquid chromatography.

    PubMed Central

    Rex, J H; Hanson, L H; Amantea, M A; Stevens, D A; Bennett, J E

    1991-01-01

    An improved bioassay for fluconazole was developed. This assay is sensitive in the clinically relevant range (2 to 40 micrograms/ml) and analyzes plasma, serum, and cerebrospinal fluid specimens; bioassay results correlate with results obtained by high-pressure liquid chromatography (HPLC). Bioassay and HPLC analyses of spiked plasma, serum, and cerebrospinal fluid samples (run as unknowns) gave good agreement with expected values. Analysis of specimens from patients gave equivalent results by both HPLC and bioassay. HPLC had a lower within-run coefficient of variation (less than 2.5% for HPLC versus less than 11% for bioassay) and a lower between-run coefficient of variation (less than 5% versus less than 12% for bioassay) and was more sensitive (lower limit of detection, 0.1 micrograms/ml [versus 2 micrograms/ml for bioassay]). The bioassay is, however, sufficiently accurate and sensitive for clinical specimens, and its relative simplicity, low sample volume requirement, and low equipment cost should make it the technique of choice for analysis of routine clinical specimens. PMID:1854166

  13. Internal dosimetry technical basis manual

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-12-20

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophicalmore » discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.« less

  14. A novel bioassay to evaluate Beauveria bassiana strain NI8 and the insect growth regulator, novaluron, against Lygus lineolaris on a non-autoclaved solid artificial diet

    USDA-ARS?s Scientific Manuscript database

    Detailed life-tables studies or more quantitative estimates of the impact of control agents on TPB life history require a bioassay option to study the impact of prolonged exposure for weeks following contact with the control agent. This is difficult with plant tissue that must be routinely replaced ...

  15. Structuring a risk-based bioassay program for uranium usage in university laboratories

    NASA Astrophysics Data System (ADS)

    Dawson, Johnne Talia

    Bioassay programs are integral in a radiation safety program. They are used as a method of determining whether individuals working with radioactive material have been exposed and have received a resulting dose. For radionuclides that are not found in nature, determining an exposure is straightforward. However, for a naturally occurring radionuclide like uranium, it is not as straightforward to determine whether a dose is the result of an occupational exposure. The purpose of this project is to address this issue within the University of Nevada, Las Vegas's (UNLV) bioassay program. This project consisted of two components that studied the effectiveness of a bioassay program in determining the dose for an acute inhalation of uranium. The first component of the plan addresses the creation of excretion curves, utilizing MATLAB that would allow UNLV to be able to determine at what time an inhalation dose can be attributed to. The excretion curves were based on the ICRP 30 lung model, as well as the Annual Limit Intake (ALI) values located in the Nuclear Regulatory Commission's 10CFR20 which is based on ICRP 30 (International Commission on Radiological Protection). The excretion curves would allow UNLV to be able to conduct in-house investigations of inhalation doses without solely depending on outside investigations and sources. The second component of the project focused on the creation of a risk based bioassay program to be utilized by UNLV that would take into account bioassay frequency that depended on the individual. Determining the risk based bioassay program required the use of baseline variance in order to minimize the investigation of false positives among those individuals who undergo bioassays for uranium work. The proposed program was compared against an evaluation limit of 10 mrem per quarter, an investigational limit of 125 mrem per quarter, and the federal/state requirement of 1.25 rem per quarter. It was determined that a bioassay program whose bioassay frequency varies per person, depending on the chemical class of material being worked with, in conjunction with continuous air monitoring can sufficiently meet ALARA standards.

  16. Technical requirements for bioassay support services

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hickman, D.P.; Anderson, A.L.

    1991-05-01

    This document provides the technical basis for the Chem-Nuclear Geotech (Geotech) bioassay program. It includes information and details that can be used as a model in providing technical contents and requirements for bioassay laboratory support, either internally or in solicitations by Geotech to obtain subcontractor laboratory support. It provides a detailed summary and description of the types of bioassay samples to be expected in support of Geotech remedial projects for the US Department of Energy and the bioassay services and analytical requirements necessary to process such samples, including required limits of sensitivity. General responsibilities of the bioassay laboratory are alsomore » addressed, including quality assurance. Peripheral information of importance to the program is included in the appendices of this document. 7 tabs.« less

  17. A survey on uncertainty in bioassay measurements carried out within the OMINEX project.

    PubMed

    Hurtgen, C; Cossonnet, C

    2003-01-01

    One of the topics covered by the OMINEX (Optimisation of Monitoring for Internal Exposure) project was to look at the bioassay measurements performed in the European laboratories. Questionnaires on bioassay measurements by alpha spectrometry or inductively coupled plasma-mass spectrometry (ICP-MS) were sent to European laboratories. The main objective was to collect information on analytical procedures and on the uncertainties associated with bioassay results. Alpha spectrometry is the technique most often used for the determination of alpha emitters, such as actinides in biological samples. ICP-MS is not used much as yet for routine measurements of actinides in biological samples, but is very sensitive for measurements of long-lived radionuclides. The different parameters influencing the uncertainties on the results and the minimum detectable amount have been investigated. Optimum conditions for achieving low result uncertainties and high sensitivity are given for alpha spectrometry and ICP-MS.

  18. The use of Ampelisca abdita growth rate as an indicator of sediment quality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weston, D.P.; Thompson, B.

    1995-12-31

    Acute lethal bioassays with amphipod crustaceans are routinely used to assess toxicity of bulk sediments. A study within the San Francisco Bay Regional Monitoring Program (RMP) is in progress to develop a chronic bioassay with the amphipod Ampelisca abdita, measuring both survivorship and growth rates. This approach is attractive because depression of growth rate is likely to be a more sensitive indicator of toxic effects than acute lethality, and natural populations of A. abdita exist throughout the Bay. Spiked sediment bioassays, using cadmium and crude oil, were used to demonstrate the relative sensitivity of the standard 10-day lethal test vs.more » the 30-day growth test. Sediments were also collected from 9 sites throughout the Bay, ranging from areas adjacent to municipal wastewater discharges to areas distant from known point source inputs. These samples were then split, and used for side-by-side comparison of acute (lethal) and chronic (growth) toxicity tests. Survivorship exceeded 90% in all tests, including those sediments collected nearest the wastewater outfalls. Growth rates were contrasted among the various treatments to examine the utility of this end point in discriminating the outfall sites. Data on the spatial distribution, abundance, and size-frequency distribution of native populations was examined within the context of using growth rate as an indicator of toxic effects in natural populations as well.« less

  19. Methods for conducting bioassays using embryos and larvae of Pacific herring, Clupea pallasi.

    PubMed

    Dinnel, Paul A; Middaugh, Douglas P; Schwarck, Nathan T; Farren, Heather M; Haley, Richard K; Hoover, Richard A; Elphick, James; Tobiason, Karen; Marshall, Randall R

    2011-02-01

    The rapid decrease of several stocks of Pacific herring, Clupea pallasi, in Puget Sound, Washington, has led to concerns about the effects of industrial and nonpoint source contamination on the embryo and larval stages of this and related forage fish species. To address these concerns, the state of Washington and several industries have funded efforts to develop embryo and larval bioassay protocols that can be used by commercial laboratories for routine effluent testing. This article presents the results of research to develop herring embryo and larval bioassay protocols. Factors evaluated during protocol development included temperature, salinity, dissolved oxygen (DO), light intensity, photoperiod, larval feeding regimes, use of brine and artificial sea salts, gonad sources, collection methods, and egg quality.

  20. The Structure of Algal Population in the Presence of Toxicants

    NASA Astrophysics Data System (ADS)

    Ipatova, Valentina; Prokhotskaya, Valeria; Dmitrieva, Aida

    Algal bioassays are routinely employed as part of a battery of toxicity tests to assess the environmental impacts of contaminants on aquatic ecosystems. This estimation is an essential component of the ecological risk assessment.

  1. In Vitro Androgen Bioassays as a Detection Method for Designer Androgens

    PubMed Central

    Cooper, Elliot R.; McGrath, Kristine C. Y.; Heather, Alison K.

    2013-01-01

    Androgens are the class of sex steroids responsible for male sexual characteristics, including increased muscle mass and decreased fat mass. Illicit use of androgen doping can be an attractive option for those looking to enhance sporting performance and/or physical appearance. The use of in vitro bioassays to detect androgens, especially designer or proandrogens, is becoming increasingly important in combating androgen doping associated with nutritional supplements. The nutritional sports supplement market has grown rapidly throughout the past decade. Many of these supplements contain androgens, designer androgens or proandrogens. Many designer or proandrogens cannot be detected by the standard highly-sensitive screening methods such as gas chromatography-mass spectrometry because their chemical structure is unknown. However, in vitro androgen bioassays can detect designer and proandrogens as these assays are not reliant on knowing the chemical structure but instead are based on androgen receptor activation. For these reasons, it may be advantageous to use routine androgen bioassay screening of nutraceutical samples to help curb the increasing problem of androgen doping. PMID:23389345

  2. Emergency radiobioassay preparedness exercises through the NIST radiochemistry intercomparison program.

    PubMed

    Nour, Svetlana; LaRosa, Jerry; Inn, Kenneth G W

    2011-08-01

    The present challenge for the international emergency radiobioassay community is to analyze contaminated samples rapidly while maintaining high quality results. The National Institute of Standards and Technology (NIST) runs a radiobioassay measurement traceability testing program to evaluate the radioanalytical capabilities of participating laboratories. The NIST Radiochemistry Intercomparison Program (NRIP) started more than 10 years ago, and emergency performance testing was added to the program seven years ago. Radiobioassay turnaround times under the NRIP program for routine production and under emergency response scenarios are 60 d and 8 h, respectively. Because measurement accuracy and sample turnaround time are very critical in a radiological emergency, response laboratories' analytical systems are best evaluated and improved through traceable Performance Testing (PT) programs. The NRIP provides participant laboratories with metrology tools to evaluate their performance and to improve it. The program motivates the laboratories to optimize their methodologies and minimize the turnaround time of their results. Likewise, NIST has to make adjustments and periodical changes in the bioassay test samples in order to challenge the participating laboratories continually. With practice, radioanalytical measurements turnaround time can be reduced to 3-4 h.

  3. Altered Axial Skeletal Development

    EPA Science Inventory

    The axial skeleton is routinely examined in standard developmental toxicity bioassays and has proven to be sensitive to a wide variety of chemical agents. Dysmorphogenesis in the skull, vertebral column and ribs has been described in both human populations and in laboratory anima...

  4. Benchmarking organic micropollutants in wastewater, recycled water and drinking water with in vitro bioassays.

    PubMed

    Escher, Beate I; Allinson, Mayumi; Altenburger, Rolf; Bain, Peter A; Balaguer, Patrick; Busch, Wibke; Crago, Jordan; Denslow, Nancy D; Dopp, Elke; Hilscherova, Klara; Humpage, Andrew R; Kumar, Anu; Grimaldi, Marina; Jayasinghe, B Sumith; Jarosova, Barbora; Jia, Ai; Makarov, Sergei; Maruya, Keith A; Medvedev, Alex; Mehinto, Alvine C; Mendez, Jamie E; Poulsen, Anita; Prochazka, Erik; Richard, Jessica; Schifferli, Andrea; Schlenk, Daniel; Scholz, Stefan; Shiraishi, Fujio; Snyder, Shane; Su, Guanyong; Tang, Janet Y M; van der Burg, Bart; van der Linden, Sander C; Werner, Inge; Westerheide, Sandy D; Wong, Chris K C; Yang, Min; Yeung, Bonnie H Y; Zhang, Xiaowei; Leusch, Frederic D L

    2014-01-01

    Thousands of organic micropollutants and their transformation products occur in water. Although often present at low concentrations, individual compounds contribute to mixture effects. Cell-based bioassays that target health-relevant biological endpoints may therefore complement chemical analysis for water quality assessment. The objective of this study was to evaluate cell-based bioassays for their suitability to benchmark water quality and to assess efficacy of water treatment processes. The selected bioassays cover relevant steps in the toxicity pathways including induction of xenobiotic metabolism, specific and reactive modes of toxic action, activation of adaptive stress response pathways and system responses. Twenty laboratories applied 103 unique in vitro bioassays to a common set of 10 water samples collected in Australia, including wastewater treatment plant effluent, two types of recycled water (reverse osmosis and ozonation/activated carbon filtration), stormwater, surface water, and drinking water. Sixty-five bioassays (63%) showed positive results in at least one sample, typically in wastewater treatment plant effluent, and only five (5%) were positive in the control (ultrapure water). Each water type had a characteristic bioanalytical profile with particular groups of toxicity pathways either consistently responsive or not responsive across test systems. The most responsive health-relevant endpoints were related to xenobiotic metabolism (pregnane X and aryl hydrocarbon receptors), hormone-mediated modes of action (mainly related to the estrogen, glucocorticoid, and antiandrogen activities), reactive modes of action (genotoxicity) and adaptive stress response pathway (oxidative stress response). This study has demonstrated that selected cell-based bioassays are suitable to benchmark water quality and it is recommended to use a purpose-tailored panel of bioassays for routine monitoring.

  5. Country-level operational implementation of the Global Plan for Insecticide Resistance Management

    PubMed Central

    Hemingway, Janet; Vontas, John; Poupardin, Rodolphe; Raman, Jaishree; Lines, Jo; Schwabe, Chris; Matias, Abrahan; Kleinschmidt, Immo

    2013-01-01

    Malaria control is reliant on the use of long-lasting pyrethroid-impregnated nets and/or indoor residual spraying (IRS) of insecticide. The rapid selection and spread of operationally significant pyrethroid resistance in African malaria vectors threatens our ability to sustain malaria control. Establishing whether resistance is operationally significant is technically challenging. Routine monitoring by bioassay is inadequate, and there are limited data linking resistance selection with changes in disease transmission. The default is to switch insecticides when resistance is detected, but limited insecticide options and resistance to multiple insecticides in numerous locations make this approach unsustainable. Detailed analysis of the resistance situation in Anopheles gambiae on Bioko Island after pyrethroid resistance was detected in this species in 2004, and the IRS program switched to carbamate bendiocarb, has now been undertaken. The pyrethroid resistance selected is a target-site knock-down resistance kdr-form, on a background of generally elevated metabolic activity, compared with insecticide-susceptible A. gambiae, but the major cytochrome P450-based metabolic pyrethroid resistance mechanisms are not present. The available evidence from bioassays and infection data suggests that the pyrethroid resistance mechanisms in Bioko malaria vectors are not operationally significant, and on this basis, a different, long-lasting pyrethroid formulation is now being reintroduced for IRS in a rotational insecticide resistance management program. This will allow control efforts to be sustained in a cost-effective manner while reducing the selection pressure for resistance to nonpyrethroid insecticides. The methods used provide a template for evidence-based insecticide resistance management by malaria control programs. PMID:23696658

  6. Country-level operational implementation of the Global Plan for Insecticide Resistance Management.

    PubMed

    Hemingway, Janet; Vontas, John; Poupardin, Rodolphe; Raman, Jaishree; Lines, Jo; Schwabe, Chris; Matias, Abrahan; Kleinschmidt, Immo

    2013-06-04

    Malaria control is reliant on the use of long-lasting pyrethroid-impregnated nets and/or indoor residual spraying (IRS) of insecticide. The rapid selection and spread of operationally significant pyrethroid resistance in African malaria vectors threatens our ability to sustain malaria control. Establishing whether resistance is operationally significant is technically challenging. Routine monitoring by bioassay is inadequate, and there are limited data linking resistance selection with changes in disease transmission. The default is to switch insecticides when resistance is detected, but limited insecticide options and resistance to multiple insecticides in numerous locations make this approach unsustainable. Detailed analysis of the resistance situation in Anopheles gambiae on Bioko Island after pyrethroid resistance was detected in this species in 2004, and the IRS program switched to carbamate bendiocarb, has now been undertaken. The pyrethroid resistance selected is a target-site knock-down resistance kdr-form, on a background of generally elevated metabolic activity, compared with insecticide-susceptible A. gambiae, but the major cytochrome P450-based metabolic pyrethroid resistance mechanisms are not present. The available evidence from bioassays and infection data suggests that the pyrethroid resistance mechanisms in Bioko malaria vectors are not operationally significant, and on this basis, a different, long-lasting pyrethroid formulation is now being reintroduced for IRS in a rotational insecticide resistance management program. This will allow control efforts to be sustained in a cost-effective manner while reducing the selection pressure for resistance to nonpyrethroid insecticides. The methods used provide a template for evidence-based insecticide resistance management by malaria control programs.

  7. Considerations for Bioassay Monitoring of Mixtures of Radionuclides

    DOE PAGES

    Klumpp, John; Waters, Tom; Bertelli, Luiz

    2017-10-01

    Complying with regulations for bioassay monitoring of radionuclide intakes is significantly more complex for mixtures than it is for pure radionuclides. Different constituents will naturally have different dose coefficients, be detectable at significantly different levels, and may require very different amounts of effort to bioassay. The ability to use certain constituents as surrogates for others will depend on how well characterized the mixture is, as well as whether the employee is also working with other radionuclides. This is further compounded by the fact that the composition of a mixture (or even of a pure radionuclide) is likely to change overmore » time. Internal dosimetrists must decide how best to monitor employees who work with radionuclide mixtures. In particular, they must decide which constituents should be monitored routinely, which constituents only need to be monitored in the case of an intake, and how to estimate doses based on intakes of monitored and unmonitored constituents.« less

  8. Two Case Studies of Highly Insoluble Plutonium Inhalation with Implications for Bioassay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; La Bone, Thomas R.

    2003-01-01

    Two well-characterized Pu inhalation cases show some remarkable similarities between substantially different types of Pu oxide. The circumstances of exposure, therapy, bioassay data, chemical solubility studies, and dosimetry associated with these cases suggests taht highly insoluble Pu may be more common than previously thought, and can pose significant challenges to bioassay programs.

  9. The standardized fish bioassay procedure for detecting and culturing actively toxic Pfiesteria, used by two reference laboratories for atlantic and gulf coast states.

    PubMed Central

    Burkholder, J M; Marshall, H G; Glasgow, H B; Seaborn, D W; Deamer-Melia, N J

    2001-01-01

    In the absence of purified standards of toxins from Pfiesteria species, appropriately conducted fish bioassays are the "gold standard" that must be used to detect toxic strains of Pfiesteria spp. from natural estuarine water or sediment samples and to culture actively toxic Pfiesteria. In this article, we describe the standardized steps of our fish bioassay as an abbreviated term for a procedure that includes two sets of trials with fish, following the Henle-Koch postulates modified for toxic rather than infectious agents. This procedure was developed in 1991, and has been refined over more than 12 years of experience in research with toxic Pfiesteria. The steps involve isolating toxic strains of Pfiesteria (or other potentially, as-yet-undetected, toxic Pfiesteria or Pfiesteria-like species) from fish-killing bioassays with natural samples; growing the clones with axenic algal prey; and retesting the isolates in a second set of fish bioassays. The specific environmental conditions used (e.g., temperature, salinity, light, other factors) must remain flexible, given the wide range of conditions from which natural estuarine samples are derived. We present a comparison of information provided for fish culture conditions, reported in international science journals in which such research is routinely published, and we provide information from more than 2,000 fish bioassays with toxic Pfiesteria, along with recommendations for suitable ranges and frequency of monitoring of environmental variables. We present data demonstrating that algal assays, unlike these standardized fish bioassays, should not be used to detect toxic strains of Pfiesteria spp. Finally, we recommend how quality control/assurance can be most rapidly advanced among laboratories engaged in studies that require research-quality isolates of toxic Pfiesteria spp. PMID:11677184

  10. Soil-test biological activity in corn production systems: II. Greenhouse growth bioassay

    USDA-ARS?s Scientific Manuscript database

    Soil N mineralization is variably affected by management and edaphic conditions. A routine soil test is needed to make better predictions for N fertilizer recommendations to cereal grains on different soil types and landscape settings. We collected soils from 47 corn production fields in North Car...

  11. Minimum Detectable Dose as a Measure of Bioassay Programme Capability

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.

    2003-01-01

    This paper suggests that minimum detectable dose (MDD) be used to describe the capability of bioassay programs for which intakes are expected to be rare. This allows expression of the capability in units that correspond directly to primary dose limits. The concept uses the well-established analytical statistic minimum detectable amount (MDA) as the starting point and assumes MDA detection at a prescribed time post intake. The resulting dose can then be used as an indication of the adequacy or capability of the program for demonstrating compliance with the performance criteria. MDDs can be readily tabulated or plotted to demonstrate themore » effectiveness of different types of monitoring programs. The inclusion of cost factors for bioassay measurements can allow optimisation.« less

  12. Analysis of therapeutic growth hormone preparations: report of an interlaboratory collaborative study on growth hormone assay methodologies.

    PubMed

    Bristow, A F; Jeffcoate, S L

    1992-09-01

    Recombinant DNA-derived human growth hormone (somatotropin) is widely used to treat growth hormone-deficient children. The potency of this product is determined by in-vivo bioassay in hypophysectomized rats, which is imprecise, costly and invasive, and there have been suggestions that it could safely be replaced with in-vitro or physico-chemical alternatives. In this report we present the results of a collaborative study designed to test this proposal. Somatotropin was modified by mild or severe proteolysis, mild or severe oxidation or treatment at high pH, and compared in a multi-centre collaborative study with unmodified somatotropin or with dimerized somatotropin. Participating laboratories included manufacturers and national control laboratories, and pharmacopoeial bioassays were compared with in-house in-vitro and physico-chemical bioassays. Although performing adequately with untreated somatotropin, for degraded samples the in-vivo bioassays were relatively unresponsive to changes in the growth hormone molecule. In contrast, the physico-chemical assays, in particular the reverse-phase HPLC, performed with a high degree of selectivity. We conclude that in the case of somatotropin, the in-vivo bioassay can be removed from the routine product specification with an acceptable degree of security. This however does not obviate the requirement rigorously to demonstrate biological activity in-vivo during product development, nor may the conclusions of this study be applied to other therapeutic recombinant proteins without similar collaborative investigations.

  13. Toward Streamlined Identification of Dioxin-like Compounds in Environmental Samples through Integration of Suspension Bioassay.

    PubMed

    Xiao, Hongxia; Brinkmann, Markus; Thalmann, Beat; Schiwy, Andreas; Große Brinkhaus, Sigrid; Achten, Christine; Eichbaum, Kathrin; Gembé, Carolin; Seiler, Thomas-Benjamin; Hollert, Henner

    2017-03-21

    Effect-directed analysis (EDA) is a powerful strategy to identify biologically active compounds in environmental samples. However, in current EDA studies, fractionation and handling procedures are laborious, consist of multiple evaporation steps, and thus bear the risk of contamination and decreased recoveries of the target compounds. The low resulting throughput has been one of the major bottlenecks of EDA. Here, we propose a high-throughput EDA (HT-EDA) work-flow combining reversed phase high-performance liquid chromatography fractionation of samples into 96-well microplates, followed by toxicity assessment in the micro-EROD bioassay with the wild-type rat hepatoma H4IIE cells, and chemical analysis of bioactive fractions. The approach was evaluated using single substances, binary mixtures, and extracts of sediment samples collected at the Three Gorges Reservoir, Yangtze River, China, as well as the rivers Rhine and Elbe, Germany. Selected bioactive fractions were analyzed by highly sensitive gas chromatography-atmospheric pressure laser ionization-time-of-flight-mass spectrometry. In addition, we optimized the work-flow by seeding previously adapted suspension-cultured H4IIE cells directly into the microplate used for fractionation, which makes any transfers of fractionated samples unnecessary. The proposed HT-EDA work-flow simplifies the procedure for wider application in ecotoxicology and environmental routine programs.

  14. Estimation of internal exposure to 99Mo in nuclear medicine patients.

    PubMed

    Silva, I C O A; Lucena, E A; Souza, W O; Dantas, A L A; Dantas, B M

    2010-05-10

    (99m)Tc is the most widely used radionuclide in nuclear medicine. It is obtained by elution of (99)Mo-(99m)Tc generators. Depending on the quality of the generator and its integrity, (99)Mo may be extracted from the column during the elution process, becoming a radionuclidic impurity in the (99m)Tc eluate. This fact would impart an unnecessary dose to the patients submitted to diagnostic procedures. The aim of this work is to evaluate (99)Mo incorporation and internal effective doses in nuclear medicine patients through bioassay techniques, providing information on the metabolism of molybdenum in humans. A methodology based on in vivo and in vitro measurements was developed. In vivo measurements were performed with a NaI detector installed in the IRD WBC. Urine samples were analysed with a HPGe at the IRD bioassay laboratory. Patients showed detectable activities of (99)Mo in whole body and urine. Results were interpreted with AIDE software. Estimated incorporation was compared to predicted values based on ICRP model. Effective doses were in the order of micro sieverts. Results suggest the need to implement a routine quality control program of radionuclidic impurity of (99)Mo in (99m)Tc eluates to be conducted by radiopharmacy laboratories of nuclear medicine centers.

  15. A flight cylinder bioassay as a simple, effective quality control test for Cydia pomonella

    USDA-ARS?s Scientific Manuscript database

    Assessment of quality of the sterile male insects that are being mass-reared for release in area-wide integrated pest management programmes that include a sterile insect technique component is crucial for the success of these programmes. Routine monitoring of sterile male quality needs to be carried...

  16. Pesticide toxicity index for freshwater aquatic organisms

    USGS Publications Warehouse

    Munn, Mark D.; Gilliom, Robert J.

    2001-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is designed to assess current water-quality conditions, changes in water quality over time, and the effects of natural and human factors on water quality for the Nation's streams and ground-water resources. For streams, one of the most difficult parts of the assessment is to link chemical conditions to effects on aquatic biota, particularly for pesticides, which tend to occur in streams as complex mixtures with strong seasonal patterns. A Pesticide Toxicity Index (PTI) was developed that combines pesticide exposure of aquatic biota (measured concentrations of pesticides in stream water) with toxicity estimates (standard endpoints from laboratory bioassays) to produce a single index value for a sample or site. The development of the PTI was limited to pesticide compounds routinely measured in NAWQA studies and to toxicity data readily available from existing databases. Qualifying toxicity data were found for one or more types of test organisms for 75 of the 83 pesticide compounds measured in NAWQA samples, but with a wide range of bioassays per compound (1 to 65). There were a total of 2,824 bioassays for the 75 compounds, including 287 48-hour EC50 values (concentration at which 50 percent of test organisms exhibit a nonlethal response) for freshwater cladocerans, 585 96-hour LC50 values (concentration lethal to 50 percent of test organisms) for freshwater benthic invertebrates, and 1,952 96-hour LC50 values for freshwater fish. The PTI for a particular sample is the sum of toxicity quotients (measured concentration divided by the median toxicity concentration from bioassays) for each detected pesticide. The PTI can be calculated for specific groups of pesticides and for specific taxonomic groups.While the PTI does not determine whether water in a sample is toxic, its values can be used to rank or compare the toxicity of samples or sites on a relative basis for use in further analysis or additional assessments. The PTI approach may be useful as a basis for comparing the potential significance of pesticides in different streams on a common basis, for evaluating relations between pesticide exposure and observed biological conditions, and for prioritizing where further studies are most needed.

  17. Comparative susceptibility of bemisia tabaci to imidacloprid in field- and laboratory-based bioassays

    USDA-ARS?s Scientific Manuscript database

    Bemisia tabaci biotype B is a resistance-prone pest of protected and open agriculture. Systemic uptake bioassays used in resistance monitoring programs have provided important information on susceptibility to neonicotinoid insecticides, but have remained decoupled from field performance. Simultaneou...

  18. Scrubchem: Building Bioactivity Datasets from Pubchem Bioassay Data (SOT)

    EPA Science Inventory

    The PubChem Bioassay database is a non-curated public repository with data from 64 sources, including: ChEMBL, BindingDb, DrugBank, EPA Tox21, NIH Molecular Libraries Screening Program, and various other academic, government, and industrial contributors. Methods for extracting th...

  19. Hanford Internal Dosimetry Project manual. Revision 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, E.H.; Bihl, D.E.; MacLellan, J.A.

    1994-07-01

    This document describes the Hanford Internal Dosimetry Project, as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy and its Hanford contractors. Project services include administrating the bioassay monitoring program, evaluating and documenting assessment of potential intakes and internal dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. Specific chapters deal with the following subjects: practices of the project, including interpretation of applicable DOE Orders, regulations, andmore » guidance into criteria for assessment, documentation, and reporting of doses; assessment of internal dose, including summary explanations of when and how assessments are performed; recording and reporting practices for internal dose; selection of workers for bioassay monitoring and establishment of type and frequency of bioassay measurements; capability and scheduling of bioassay monitoring services; recommended dosimetry response to potential internal exposure incidents; quality control and quality assurance provisions of the program.« less

  20. A Carcinogenicity Bioassay of Isobutyl 2-Cyanoacrylate (IBC) in Fischer-344 Rats

    DTIC Science & Technology

    1990-01-23

    subcutaneous mass M Control 084 24 Oct 85 Pallor, weak, depressed M Low IBC 080 24 Oct 85 Died in cage M High IBC 203 24 Oct 85 Pallor, large M Low IBC intra...abdominal mass 424 25 Oct 85 Weight loss, dehydrated, F High IBC depressed * Animals were sacrificed to conserve tissues in face of imminent death...bioassays due to its low incidence of spontaneous mammary gland and liver cancer . This strain is recommended by the NCI Carcinogenesis Bioassay Program

  1. Assessing acute toxicity of effluent from a textile industry and nearby river waters using sulfur-oxidizing bacteria in continuous mode.

    PubMed

    Gurung, Anup; Hassan, Sedky H A; Oh, Sang-Eun

    2011-10-01

    Bioassays are becoming an important tool for assessing the toxicity of complex mixtures of substances in aquatic environments in which Daphnia magna is routinely used as a test organism. Bioassays outweigh physicochemical analyses and are valuable in the decision-making process pertaining to the final discharge of effluents from wastewater treatment plants as they measure the total effect of the discharge which is ecologically relevant. In this study, the aquatic toxicity of a textile plant effluent and river water downstream from the plant were evaluated with sulfur-oxidizing bacterial biosensors in continuous mode. Collected samples were analysed for different physicochemical parameters and 1,4-dioxane was detected in the effluent. The effluent contained a relatively high chemical oxygen demand of 60 mg L(-1), which exceeded the limit set by the Korean government for industrial effluent discharges. Results showed that both the effluent and river waters were toxic to sulfur-oxidizing bacteria. These results show the importance of incorporating bioassays to detect toxicity in wastewater effluents for the sustainable management of water resources.

  2. Protocols for Robust Herbicide Resistance Testing in Different Weed Species.

    PubMed

    Panozzo, Silvia; Scarabel, Laura; Collavo, Alberto; Sattin, Maurizio

    2015-07-02

    Robust protocols to test putative herbicide resistant weed populations at whole plant level are essential to confirm the resistance status. The presented protocols, based on whole-plant bioassays performed in a greenhouse, can be readily adapted to a wide range of weed species and herbicides through appropriate variants. Seed samples from plants that survived a field herbicide treatment are collected and stored dry at low temperature until used. Germination methods differ according to weed species and seed dormancy type. Seedlings at similar growth stage are transplanted and maintained in the greenhouse under appropriate conditions until plants have reached the right growth stage for herbicide treatment. Accuracy is required to prepare the herbicide solution to avoid unverifiable mistakes. Other critical steps such as the application volume and spray speed are also evaluated. The advantages of this protocol, compared to others based on whole plant bioassays using one herbicide dose, are related to the higher reliability and the possibility of inferring the resistance level. Quicker and less expensive in vivo or in vitro diagnostic screening tests have been proposed (Petri dish bioassays, spectrophotometric tests), but they provide only qualitative information and their widespread use is hindered by the laborious set-up that some species may require. For routine resistance testing, the proposed whole plant bioassay can be applied at only one herbicide dose, so reducing the costs.

  3. RECOMMENDATIONS FOR UO3 PLANT BIOASSAY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.

    2010-07-12

    Alternative urine bioassay programs are described for application with decontamination and decommissioning activities at the Hanford UO3 Plant. The alternatives are based on quarterly or monthly urine bioassay for recycled uranium, assuming multiple acute inhalation intakes of recycled uranium occurring over a year. The inhalations are assumed to be 5µm AMAD particles of 80% absorption type F and 20% absorption type M. Screening levels, expressed as daily uranium mass excretion rates in urine, and the actions associated with these levels are provided for both quarterly and monthly sampling frequencies.

  4. Screening for the presence of lipophilic marine biotoxins in shellfish samples using the neuro-2a bioassay.

    PubMed

    Bodero, Marcia; Bovee, Toine F H; Wang, Si; Hoogenboom, Ron L A P; Klijnstra, Mirjam D; Portier, Liza; Hendriksen, Peter J M; Gerssen, Arjen

    2018-02-01

    The neuro-2a bioassay is considered as one of the most promising cell-based in vitro bioassays for the broad screening of seafood products for the presence of marine biotoxins. The neuro-2a assay has been shown to detect a wide array of toxins like paralytic shellfish poisons (PSPs), ciguatoxins, and also lipophilic marine biotoxins (LMBs). However, the neuro-2a assay is rarely used for routine testing of samples due to matrix effects that, for example, lead to false positives when testing for LMBs. As a result there are only limited data on validation and evaluation of its performance on real samples. In the present study, the standard extraction procedure for LMBs was adjusted by introducing an additional clean-up step with n-hexane. Recovery losses due to this extra step were less than 10%. This wash step was a crucial addition in order to eliminate false-positive outcomes due to matrix effects. Next, the applicability of this assay was assessed by testing a broad range of shellfish samples contaminated with various LMBs, including diarrhetic shellfish toxins/poisons (DSPs). For comparison, the samples were also analysed by LC-MS/MS. Standards of all regulated LMBs were tested, including analogues of some of these toxins. The neuro-2a cells showed good sensitivity towards all compounds. Extracts of 87 samples, both blank and contaminated with various toxins, were tested. The neuro-2a outcomes were in line with those of LC-MS/MS analysis and support the applicability of this assay for the screening of samples for LMBs. However, for use in a daily routine setting, the test might be further improved and we discuss several recommended modifications which should be considered before a full validation is carried out.

  5. Detection of genotoxic and non-genotoxic carcinogens in Xpc(-/-)p53(+/-) mice.

    PubMed

    Melis, Joost P M; Speksnijder, Ewoud N; Kuiper, Raoul V; Salvatori, Daniela C F; Schaap, Mirjam M; Maas, Saskia; Robinson, Joke; Verhoef, Aart; van Benthem, Jan; Luijten, Mirjam; van Steeg, Harry

    2013-01-15

    An accurate assessment of the carcinogenic potential of chemicals and pharmaceutical drugs is essential to protect humans and the environment. Therefore, substances are extensively tested before they are marketed to the public. Currently, the rodent two-year bioassay is still routinely used to assess the carcinogenic potential of substances. However, over time it has become clear that this assay yields false positive results and also has several economic and ethical drawbacks including the use of large numbers of animals, the long duration, and the high cost. The need for a suitable alternative assay is therefore high. Previously, we have proposed the Xpa*p53 mouse model as a very suitable alternative to the two-year bioassay. We now show that the Xpc*p53 mouse model preserves all the beneficial traits of the Xpa*p53 model for sub-chronic carcinogen identification and can identify both genotoxic and non-genotoxic carcinogens. Moreover, Xpc*p53 mice appear to be more responsive than Xpa*p53 mice towards several genotoxic and non-genotoxic carcinogens. Furthermore, Xpc*p53 mice are far less sensitive than Xpa*p53 mice for the toxic activity of DNA damaging agents and as such clearly respond in a similar way as wild type mice do. These advantageous traits of the Xpc*p53 model make it a better alternative for in vivo carcinogen testing than Xpa*p53. This pilot study suggests that Xpc*p53 mice are suited for routine sub-chronic testing of both genotoxic and non-genotoxic carcinogens and as such represent a suitable alternative to possibly replace the murine life time cancer bioassay. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Risky Business: Challenges and Successes in Military Radiation Risk Communication

    DTIC Science & Technology

    2012-01-01

    looted by local Iraqis. The decision was quickly made to assemble a special scientifi c team from within USACHPPM and expedite its dispatch to Iraq ...Military Police (MP) Company, New York Army National Guard, redeployed from Iraq and were inappropriately denied routine postdeployment bioassay...the medical specimens to a nonaccred- ited geology laboratory, depleted uranium was detected (though no amounts reported) and the story immediately

  7. Detection of genotoxic and non-genotoxic carcinogens in Xpc{sup −/−}p53{sup +/−} mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Melis, Joost P.M.; Leiden University Medical Center, Department of Toxicogenetics, Leiden; Speksnijder, Ewoud N.

    2013-01-15

    An accurate assessment of the carcinogenic potential of chemicals and pharmaceutical drugs is essential to protect humans and the environment. Therefore, substances are extensively tested before they are marketed to the public. Currently, the rodent two-year bioassay is still routinely used to assess the carcinogenic potential of substances. However, over time it has become clear that this assay yields false positive results and also has several economic and ethical drawbacks including the use of large numbers of animals, the long duration, and the high cost. The need for a suitable alternative assay is therefore high. Previously, we have proposed themore » Xpa*p53 mouse model as a very suitable alternative to the two-year bioassay. We now show that the Xpc*p53 mouse model preserves all the beneficial traits of the Xpa*p53 model for sub-chronic carcinogen identification and can identify both genotoxic and non-genotoxic carcinogens. Moreover, Xpc*p53 mice appear to be more responsive than Xpa*p53 mice towards several genotoxic and non-genotoxic carcinogens. Furthermore, Xpc*p53 mice are far less sensitive than Xpa*p53 mice for the toxic activity of DNA damaging agents and as such clearly respond in a similar way as wild type mice do. These advantageous traits of the Xpc*p53 model make it a better alternative for in vivo carcinogen testing than Xpa*p53. This pilot study suggests that Xpc*p53 mice are suited for routine sub-chronic testing of both genotoxic and non-genotoxic carcinogens and as such represent a suitable alternative to possibly replace the murine life time cancer bioassay. Highlights: ► The Xpc*p53 mouse model is able to identify genotoxic and non-genotoxic carcinogens. ► Time, animals and cost can be significantly reduced compared to the 2-year bioassay. ► Xpc*p53 mice are more advantageous for carcinogen identification than Xpa*p53 mice. ► Xpc*p53 mice exhibit a wild type response upon exposure to genotoxicants.« less

  8. ScrubChem: Cleaning of PubChem Bioassay Data to Create Diverse and Massive Bioactivity Datasets for Use in Modeling Applications (SOT)

    EPA Science Inventory

    The PubChem Bioassay database is a non-curated public repository with bioactivity data from 64 sources, including: ChEMBL, BindingDb, DrugBank, Tox21, NIH Molecular Libraries Screening Program, and various academic, government, and industrial contributors. However, this data is d...

  9. The OECD program to validate the rat Hershberger bioassay to screen compounds for in vivo and androgen and antiandrogen responses: Phase-2 dose-response studies

    EPA Science Inventory

    DESIGN: The Hershberger bioassay is designed to identify suspected androgens and antiandrogens based on changes in the weights of five androgen-responsive tissues (ventral prostate, paired seminal vesicles and coagulating glands, the levator ani and bulbocavernosus muscles, the g...

  10. Accreditation and training on internal dosimetry in a laboratory network in Brazil: an increasing demand.

    PubMed

    Dantas, B M; Dantas, A L A; Acar, M E D; Cardoso, J C S; Julião, L M Q C; Lima, M F; Taddei, M H T; Arine, D R; Alonso, T; Ramos, M A P; Fajgelj, A

    2011-03-01

    In recent years, Brazilian Nuclear Programme has been reviewed and updated by government authorities in face of the demand for energy supply and its associated environmental constraints. The immediate impact of new national programmes and projects in nuclear field is the increase in the number of exposed personnel and the consequent need for reliable dosimetry services in the country. Several Technical Documents related to internal dosimetry have been released by the International Atomic Energy Agency and International Commission on Radiological Protection. However, standard bioassay procedures and methodologies for bioassay data interpretation are still under discussion and, in some cases, both in routine and emergency internal monitoring, procedures can vary from one laboratory to another and responses may differ markedly among Dosimetry Laboratories. Thus, it may be difficult to interpret and use bioassay data generated from different laboratories of a network. The main goal of this work is to implement a National Network of Laboratories aimed to provide reliable internal monitoring services in Brazil. The establishment of harmonised in vivo and in vitro radioanalytical techniques, dose assessment methods and the implementation of the ISO/IEC 17025 requirements will result in the recognition of technical competence of the network.

  11. Pesticide toxicity index for freshwater aquatic organisms, 2nd edition

    USGS Publications Warehouse

    Munn, Mark D.; Gilliom, Robert J.; Moran, Patrick W.; Nowell, Lisa H.

    2006-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is designed to assess current water-quality conditions, changes in water quality over time, and the effects of natural and human factors on water quality for the Nation's streams and ground-water resources. For streams, one of the most difficult parts of the assessment is to link chemical conditions to effects on aquatic biota, particularly for pesticides, which tend to occur in streams as complex mixtures with strong seasonal patterns. A Pesticide Toxicity Index (PTI) was developed that combines pesticide exposure of aquatic biota (measured concentrations of pesticides in stream water) with acute toxicity estimates (standard endpoints from laboratory bioassays) to produce a single index value for a sample or site. The development of the PTI was limited to pesticide compounds routinely measured in NAWQA studies and to toxicity data readily available from existing databases. Qualifying toxicity data were found for one or more types of test organisms for 124 of the 185 pesticide compounds measured in NAWQA samples, but with a wide range of available bioassays per compound (1 to 232). In the databases examined, there were a total of 3,669 bioassays for the 124 compounds, including 398 48-hour EC50 values (concentration at which 50 percent of test organisms exhibit a sublethal response) for freshwater cladocerans, 699 96-hour LC50 values (concentration lethal to 50 percent of test organisms) for freshwater benthic invertebrates, and 2,572 96-hour LC50 values for freshwater fish. The PTI for a particular sample is the sum of toxicity quotients (measured concentration divided by the median toxicity concentration from bioassays) for each detected pesticide, and thus, is based on the concentration addition model of pesticide toxicity. The PTI can be calculated for specific groups of pesticides and for specific taxonomic groups. Although the PTI does not determine whether water in a sample is toxic to aquatic organisms, its values can be used to rank or compare the toxicity of samples or sites on a relative basis for use in further analysis or additional assessments. The PTI approach may be useful as a basis for comparing the potential significance of pesticides in different streams on a common basis, for evaluating relations between pesticide exposure and observed biological conditions, and for prioritizing where further studies are most needed.

  12. BioAssay Research Database (BARD): chemical biology and probe-development enabled by structured metadata and result types

    PubMed Central

    Howe, E.A.; de Souza, A.; Lahr, D.L.; Chatwin, S.; Montgomery, P.; Alexander, B.R.; Nguyen, D.-T.; Cruz, Y.; Stonich, D.A.; Walzer, G.; Rose, J.T.; Picard, S.C.; Liu, Z.; Rose, J.N.; Xiang, X.; Asiedu, J.; Durkin, D.; Levine, J.; Yang, J.J.; Schürer, S.C.; Braisted, J.C.; Southall, N.; Southern, M.R.; Chung, T.D.Y.; Brudz, S.; Tanega, C.; Schreiber, S.L.; Bittker, J.A.; Guha, R.; Clemons, P.A.

    2015-01-01

    BARD, the BioAssay Research Database (https://bard.nih.gov/) is a public database and suite of tools developed to provide access to bioassay data produced by the NIH Molecular Libraries Program (MLP). Data from 631 MLP projects were migrated to a new structured vocabulary designed to capture bioassay data in a formalized manner, with particular emphasis placed on the description of assay protocols. New data can be submitted to BARD with a user-friendly set of tools that assist in the creation of appropriately formatted datasets and assay definitions. Data published through the BARD application program interface (API) can be accessed by researchers using web-based query tools or a desktop client. Third-party developers wishing to create new tools can use the API to produce stand-alone tools or new plug-ins that can be integrated into BARD. The entire BARD suite of tools therefore supports three classes of researcher: those who wish to publish data, those who wish to mine data for testable hypotheses, and those in the developer community who wish to build tools that leverage this carefully curated chemical biology resource. PMID:25477388

  13. A rapid chemiluminescent slot blot immunoassay for the detection and quantification of Clostridium botulinum neurotoxin type E, in cultures.

    PubMed

    Cadieux, Brigitte; Blanchfield, Burke; Smith, James P; Austin, John W

    2005-05-01

    A simple, rapid, cost-effective in vitro slot blot immunoassay was developed for the detection and quantification of botulinum neurotoxin type E (BoNT/E) in cultures. Culture supernatants of 36 strains of clostridia, including 12 strains of Clostridium botulinum type E, 12 strains of other C. botulinum neurotoxin serotypes, and 12 strains of other clostridial species were tested. Samples containing BoNT/E were detected using affinity-purified polyclonal rabbit antisera prepared against BoNT/E with subsequent detection of secondary antibodies using chemiluminescence. All strains of C. botulinum type E tested positive, while all non C. botulinum type E strains tested negative. The sensitivity of the slot blot immunoassay for detection of BoNT/E was approximately four mouse lethal doses (MLD). The intensity of chemiluminescence was directly correlated with the concentration of BoNT/E up to 128 MLD, allowing quantification of BoNT/E between 4 and 128 MLD. The slot blot immunoassay was compared to the mouse bioassay for detection of BoNT/E using cultures derived from fish samples inoculated with C. botulinum type E, and cultures derived from naturally contaminated environmental samples. A total of 120 primary enrichment cultures derived from fish samples, of which 103 were inoculated with C. botulinum type E, and 17 were uninoculated controls, were assayed. Of the 103 primary enrichment cultures derived from inoculated fish samples, all were positive by mouse bioassay, while 94 were also positive by slot blot immunoassay, resulting in a 7.5% false-negative rate. All 17 primary enrichment cultures derived from the uninoculated fish samples were negative by both mouse bioassay and slot blot immunoassay. A total of twenty-six primary enrichment cultures derived from environmental samples were tested by mouse bioassay and slot blot immunoassay. Of 13 primary enrichment cultures positive by mouse bioassay, 12 were also positive by slot blot immunoassay, resulting in a 3.8% false-negative rate. All 13 primary enrichment cultures that tested negative by mouse bioassay also tested negative by slot blot immunoassay. The slot blot immunoassay could be used routinely as a positive screen for BoNT/E in primary enrichment cultures, and could be used as a replacement for the mouse bioassay for pure cultures.

  14. PCR und ELISA - Alternativen zum Maustest für die Analyse des Botulismus-Neurotoxin-C1 Giftbildungspotentiales in Umweltproben? [PCR and ELISA - in vitro alternatives to the mouse-bioassay for assessing the botulinum-neurotoxin-C1 production potential in environmental samples?

    USGS Publications Warehouse

    Zechmeister, T.C.; Farnleitner, A.H.; Rocke, T.E.; Pittner, F.; Rosengarten, R.; Mach, R.L.; Herzig, A.; Kirschner, A.K.T.

    2002-01-01

    Botulism is one of the most important bird diseases world-wide and is caused by the intoxication with Botulinum-Neurotoxin-C1 (BoNt-C1), which is produced by toxigenic clostridia under appropriate conditions. Avian botulism leads regularly to large losses among the migrating bird populations breeding and resting at the saltwater pools of the Austrian national park Neusiedler See-Seewinkel. Despite of its ethical dubiousness and its high technical expense the mouse-bioassay is still used as the routine standard method for the detection of BoNt-C1. According to the 3R-concept, in vitro alternative methods for the qualitative detection of BoNt-C1 (immunostick-ELISA) and a corresponding BoNt-C1 gene fragment (nested-PCR) were established. In order to estimate the BoNt-C1 production potential the methods were tested with sediment samples from different saltwater pools subjected to cultivation conditions appropriate for in vitro BoNt-C1-production. With the mouse-bioassay, 52 out of 77 samples were found to have a positive toxin production potential. The immunostick-ELISA showed a similar sensitivity as the mouse-bioassay and exhibited a highly significant positive correlation (r=0.94; p<0.001) with the mouse-bioassay in detecting BoNt-C1. The nested-PCR approach revealed higher numbers of positive BoNt-C1 gene fragment detections as compared to the direct toxin analysis approaches. A weak correlation (r=0.21; p=0.07) with the mouse-bioassay was discernible, no correlation was found with the immunostick-ELISA (r=0.09; p=0.46). Obviously, the PCR approach detected the BoNt-C1 gene fragment in some of the samples where no toxin expression has occurred. Thus it is suggested that the qualitative immunostick-ELISA represents a potential in vitro alternative to the mouse-bioassay for assessing the BoNt-C1 production potential in environmental samples. In contrast, qualitative BoNt-C1 gene fragment detection via PCR led to an overestimation of the actual toxin production potential.

  15. Insecticide Resistance Management

    DTIC Science & Technology

    2013-01-01

    been a side effect of insect vector control programs since 1914, and insect disease vectors in over 45 countries are resistant to at least one...the CDC and WHO bioassays can be performed on various insects , the remainder of the guide will focus specifically on how to detect resistance in...mosquito vector populations. For a description of how to develop a bioassay for resistance testing in other groups of insects , refer to the following

  16. NV/YMP radiological control manual, Revision 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gile, A.L.

    The Nevada Test Site (NTS) and the adjacent Yucca Mountain Project (YMP) are located in Nye County, Nevada. The NTS has been the primary location for testing nuclear explosives in the continental US since 1951. Current activities include operating low-level radioactive and mixed waste disposal facilities for US defense-generated waste, assembly/disassembly of special experiments, surface cleanup and site characterization of contaminated land areas, and non-nuclear test operations such as controlled spills of hazardous materials at the hazardous Materials (HAZMAT) Spill Center (HSC). Currently, the major potential for occupational radiation exposure is associated with the burial of low-level nuclear waste andmore » the handling of radioactive sources. Planned future remediation of contaminated land areas may also result in radiological exposures. The NV/YMP Radiological Control Manual, Revision 2, represents DOE-accepted guidelines and best practices for implementing Nevada Test Site and Yucca Mountain Project Radiation Protection Programs in accordance with the requirements of Title 10 Code of Federal Regulations Part 835, Occupational Radiation Protection. These programs provide protection for approximately 3,000 employees and visitors annually and include coverage for the on-site activities for both personnel and the environment. The personnel protection effort includes a DOE Laboratory Accreditation Program accredited dosimetry and personnel bioassay programs including in-vivo counting, routine workplace air sampling, personnel monitoring, and programmatic and job-specific As Low as Reasonably Achievable considerations.« less

  17. PubChem BioAssay: A Decade's Development toward Open High-Throughput Screening Data Sharing.

    PubMed

    Wang, Yanli; Cheng, Tiejun; Bryant, Stephen H

    2017-07-01

    High-throughput screening (HTS) is now routinely conducted for drug discovery by both pharmaceutical companies and screening centers at academic institutions and universities. Rapid advance in assay development, robot automation, and computer technology has led to the generation of terabytes of data in screening laboratories. Despite the technology development toward HTS productivity, fewer efforts were devoted to HTS data integration and sharing. As a result, the huge amount of HTS data was rarely made available to the public. To fill this gap, the PubChem BioAssay database ( https://www.ncbi.nlm.nih.gov/pcassay/ ) was set up in 2004 to provide open access to the screening results tested on chemicals and RNAi reagents. With more than 10 years' development and contributions from the community, PubChem has now become the largest public repository for chemical structures and biological data, which provides an information platform to worldwide researchers supporting drug development, medicinal chemistry study, and chemical biology research. This work presents a review of the HTS data content in the PubChem BioAssay database and the progress of data deposition to stimulate knowledge discovery and data sharing. It also provides a description of the database's data standard and basic utilities facilitating information access and use for new users.

  18. Bioassay of safinamide in biological fluids of humans and various animal species.

    PubMed

    Dal Bo, Lorenzo; Mazzucchelli, Paolo; Fibbioli, Monia; Marzo, Antonio

    2006-01-01

    This paper describes three methods to bioassay safinamide (CAS 133865-89-1) in biological fluids of humans and laboratory animals for pharmacokinetic, toxicokinetic and bioavailability studies. Two methods profited from liquid chromatography tandem mass spectrometry (LC-MS-MS) system, one (micro bioassay) working in the low dynamic range 0.5-20 ng/ml, the other in the range 20-6000 ng/ml. A third method used high-performance liquid chromatrography with fluorimetric detection (HPLC-FD), working in the dynamic range 20-1000 ng/ml. All the three methods were validated in compliance with the accreditated views on analytical bioassays. The shorter run time (5.5 min vs 16 min) has led the authors to prefer the two LC-MS-MS methods to the HPLC-FD bioassay, even if all the performances of the three methods were excellent. The methods described in this paper were and are still now extensively used to assay safinamide in more than 10,000 specimens of biological fluids from humans and laboratory animals in the development program of the drug. Main pharmacokinetic results obtained in various Phase I trials on healthy volunteers are briefly reported.

  19. Evaluation of Short-Term Bioassays to Predict Functional Impairment. Development of Hepatic Bioassays in Laboratory Animals, Directory of Institutions/Individuals.

    DTIC Science & Technology

    1980-10-01

    Organizations Compounds Tested Morphological Tests Toxic Substances Functional Tests rR ACT Cutlue OM v.a e sif nemooery ad Identify by block number) %MITRE has...demonstrated ability to evaluate and predict hepatic impairment rvsulting from toxicant exposures. This directory is a companion to Selected Short-Term...Hepatic Toxicity Tests, which describes the available hepatic testing protocols and assesses their suitability for a screening program. This direc

  20. INTERNATIONAL PROGRAM ON CHEMICAL SAFETY'S COLLABORATIVE STUDY ON PLANT TEST SYSTEMS

    EPA Science Inventory

    This article presents the status report on the International Program's Collaborative Study on Plant Test Systems. n the first phase of this program, 16 laboratories submitted data on the genetic effects of EMS evaluated in three bioassays; i.e., Vicia faba root hair, Tradescantia...

  1. Items Supporting the Hanford Internal Dosimetry Program Implementation of the IMBA Computer Code

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Bihl, Donald E.

    2008-01-07

    The Hanford Internal Dosimetry Program has adopted the computer code IMBA (Integrated Modules for Bioassay Analysis) as its primary code for bioassay data evaluation and dose assessment using methodologies of ICRP Publications 60, 66, 67, 68, and 78. The adoption of this code was part of the implementation plan for the June 8, 2007 amendments to 10 CFR 835. This information release includes action items unique to IMBA that were required by PNNL quality assurance standards for implementation of safety software. Copie of the IMBA software verification test plan and the outline of the briefing given to new users aremore » also included.« less

  2. The nematode Caenorhabditis elegans as an integrated toxicological tool to assess water quality and pollution.

    PubMed

    Clavijo, Araceli; Kronberg, María Florencia; Rossen, Ariana; Moya, Aldana; Calvo, Daniel; Salatino, Santa Esmeralda; Pagano, Eduardo Antonio; Morábito, José Antonio; Munarriz, Eliana Rosa

    2016-11-01

    Determination of water quality status in rivers is critical to establish a sustainable water management policy. For this reason, over the last decades it has been recommended to perform integrated water assessments that include water quantities and physicochemical, ecological and toxicological tests. However, sometimes resources are limited and it is not possible to perform large-scale chemical determinations of pollutants or conduct numerous ecotoxicological tests. To overcome this problem we use and measure the growth, as a response parameter, of the soil nematode Caenorhabditis elegans to assess water quality in rivers. The C. elegans is a ubiquitous organism that has emerged as an important model organism in aquatic and soil toxicology research. The Tunuyán River Basin (Province of Mendoza, Argentina) has been selected as a representative traditional water monitoring system to test the applicability of the C. elegans toxicological bioassay to generate an integrated water quality evaluation. Jointly with the C. elegans toxic assays, physicochemical and bacteriological parameters were determined for each monitoring site. C. elegans bioassays help to identify different water qualities in the river basin. Multivariate statistical analysis (PCA and linear regression models) has allowed us to confirm that traditional water quality studies do not predict potential toxic effects on living organisms. On the contrary, physicochemical and bacteriological analyzes explain <62% of the C. elegans growth response variability, showing that ecotoxicological bioassays are important to obtain a realistic scenario of water quality threats. Our results confirm that the C. elegans bioassay is a sensible and suitable tool to assess toxicity and should be implemented in routine water quality monitoring. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Assessment of dioxin-like activity in ambient air particulate matter using recombinant yeast assays

    NASA Astrophysics Data System (ADS)

    Olivares, Alba; van Drooge, Barend L.; Pérez Ballesta, Pascual; Grimalt, Joan O.; Piña, Benjamin

    2011-01-01

    Ectopic activation of the aryl hydrocarbon receptor (AhR), also known as dioxin-like activity, is a major component of the toxicity associated with polycyclic aromatic hydrocarbons (PAH). Filtration of ambient air particulate matter through PM 10 filters followed by chemical determination of PAH concentrations and a yeast-based bioassay (RYA) were combined to evaluate and characterize dioxin-like activity in ambient air. Samples were collected in a semirural area of Northern Italy between September 2008 and February 2009. Total PAH contents ranged between 0.3 ng m -3 and 34 ng m -3 and were in correlation with seasonal variations of meteorological conditions and combustion processes. Dioxin-like activity values in air samples showed an excellent correlation (0.71 < R2 < 0.86) with the observed PAH concentrations and the predicted toxicity equivalents for PAH. This RYA-bioassay reported in the present study provides a simple and low-cost routine control for toxic PAH emissions, even at background air concentration levels.

  4. Towards improved biomonitoring tools for an intensified sustainable multi-use environment.

    PubMed

    van der Meer, Jan Roelof

    2016-09-01

    The increasing use of our environment for multiple contrasting activities (e.g. fisheries, tourism) will have to be accompanied by improved monitoring of environmental quality, to avoid transboundary conflicts and ensure long-term sustainable intensified usage. Biomonitoring approaches are appropriate for this, since they can integrate biological effects of environmental exposure rather than measure individual compound concentrations. Recent advances in biomonitoring concepts and tools focus on single-cell assays and purified biological components that can be miniaturized and integrated in automated systems. Despite these advances, we are still very far from being able to deploy bioassays routinely in environmental monitoring, mostly because of lack of experience in interpreting responses and insufficient robustness of the biosensors for their environmental application. Further future challenges include broadening the spectrum of detectable compounds by biosensors, accelerate response times and combining sample pretreatment strategies with bioassays. © 2016 The Author. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  5. Diagnostic Doses of Insecticides for Adult Aedes aegypti to Assess Insecticide Resistance in Cuba.

    PubMed

    Rodríguez, María Magdalena; Crespo, Ariel; Hurtado, Daymi; Fuentes, Ilario; Rey, Jorge; Bisset, Juan Andrés

    2017-06-01

    The objective of this study was to determine diagnostic doses (DDs) of 5 insecticides for the Rockefeller susceptible strain of Aedes aegypti , using the Centers for Disease Control and Prevention (CDC) bottle bioassay as a tool for monitoring insecticide resistance in the Cuban vector control program. The 30-min DD values determined in this study were 13.5 μg/ml, 6.5 μg/ml, 6 μg/ml, 90.0 μg/ml, and 15.0 μg/ml for cypermethrin, deltamethrin, lambda-cyhalothrin, chlorpyrifos, and propoxur, respectively. To compare the reliability of CDC bottle bioassay with the World Health Organization susceptible test, 3 insecticide-resistant strains were evaluated for deltamethrin and lambda-cyhalothrin. Results showed that the bottles can be used effectively from 21 to 25 days after treatment and reused up to 4 times, depending on the storage time. The CDC bottle bioassay is an effective tool to assess insecticide resistance in field populations of Ae. aegypti in Cuba and can be incorporated into vector management programs using the diagnostic doses determined in this study.

  6. Using acid insoluble ash marker ratios (diet:digesta) to predict digestibility of wheat and barley metabolizable energy and nitrogen retention in broiler chicks.

    PubMed

    Scott, T A; Hall, J W

    1998-05-01

    Routine bioassay measurements of AME or N retention of broiler diets require measurements of gross energy (GE) or N and an acid insoluble ash marker in diet, excreta, or ileal digesta. These measurements of GE and N are time-consuming and expensive in comparison to measurements of added or natural occurring levels of acid insoluble ash. Data from bioassay measurements of AME and N retention of 138 wheat and 97 barley samples (with or without enzyme) were used to develop prediction equations relying on measurements of one that uses acid insoluble ash of diet, excreta or ileal digesta and GE and N of diet only; and a second equation using only acid insoluble ash of diet, excreta, or ileal digesta. The prediction equations demonstrate that part of or all of routine bomb calorimetry measurements for GE used to determine AME of wheat- or barley-based diets could be eliminated if a prediction error of 80 kcal/kg ME or less were acceptable. The prediction of N retention as compared to AME, based in part or totally on acid insoluble ash measurements, was less accurate; the prediction errors were equal to 2.3 and 6.5% for wheat- and barley-based diets, respectively. Ongoing research to improve the determination (speed, ease, and accuracy) of acid insoluble ash could provide a useful method to assess feeding value of ingredients and commercial poultry diets.

  7. Integrative assessment of coastal pollution: Development and evaluation of sediment quality criteria from chemical contamination and ecotoxicological data

    NASA Astrophysics Data System (ADS)

    Bellas, Juan; Nieto, Óscar; Beiras, Ricardo

    2011-04-01

    Elutriate embryo-larval bioassays with sea-urchins ( Paracentrotus lividus) were conducted concurrently with chemical analyses of sediments and biota as part of an integrative assessment of pollution in highly productive coastal regions. High metal contents and organic compounds in sediments and mussels were found in localised areas from the inner part of the estuaries indicating a clear anthropogenic influence. In particular, average maximum concentrations of 2803 mg Cu/kg dw, 776 mg Pb/kg dw, 2.5 mg Hg/kg dw and 5803 μg ∑ 7PAHs/kg dw were measured in sediments from the most polluted sites. Significant correlations were observed between sediment chemistry and toxicity bioassays. Moreover, the Mantel test revealed a significant correlation ( rM=0.80; p<0.01) between sediment pollutant concentrations and toxicity data profiles. In addition, sediment quality criteria were used to help in the ecological interpretation of sediment chemistry data and to identify pollutants of concern. The toxicity bioassays identified polluted sites and quantified the level of toxicity, providing a cost-effective tool to complement the routine chemical monitoring currently conducted in European coastal waters with ecologically relevant information. This is in line with the recent European legislation that advocates the use of biological tools with the ultimate aim of protecting marine resources from anthropogenic substances that will affect their sensitive early life stages.

  8. Sediment toxicity assessment in the Lagoon of Venice (Italy) using Paracentrotus lividus (Echinodermata: Echinoidea) fertilization and embryo bioassays.

    PubMed

    Volpi Ghirardini, A; Arizzi Novelli, A; Tagliapietra, D

    2005-09-01

    The capacity of two toxicity bioassays (fertilization and embryo toxicity tests) to discriminate sediment toxicity using the sea urchin Paracentrotus lividus was tested in five stations with different levels of pollution in the Lagoon of Venice. Two stations were located in estuarine sites, two in the industrial zone, and one in a site at the top of our quality gradient (reference). Elutriate was chosen as sediment matrix to assess the potential effects of bioavailable pollutants in the water column as a consequence of sediment resuspension (dredging and dumping, fishing gear, etc.). An experimental design based on Quality Assurance/Quality Control procedures (QA/QC) was adopted in order to set the methodological basis for an effective use of these bioassays in monitoring programs. Results revealed both higher embriotoxicity than spermiotoxicity in all stations and the efficacy of combined use of both toxicity bioassays in discriminating differing pollution/bioavailability between stations and periods. The good representativeness of the integrated sampling scheme and the standardization of all experimental phases yielded high precision of results. Clear Toxicity Fingerprints were evidenced for the investigated sites through the combined use of both bioassays. A good fit between ecotoxicological data and chemical contamination levels was found, except for unnatural sediment texture.

  9. Bivalve embryo bioassay to assess the potential toxicity of dredged material before dumping

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quiniou, F.

    1995-12-31

    Dredged harbor sediments frequently contain a wide spectrum of contaminants in addition to a significant percentage of organic matter. Also, dredging and dumping activities into sea water, of these highly contaminated soil may induce a harmful effect on the environment. In France, in accordance with Oslo convention guidelines, a working group on dredging activities and environment (GEODE) created since 1991 decided to set up a pilot research program to assess the intrinsic toxicity of four harbor sludges. Intrinsic toxicity of harbor muds were tested by solid phase (whole sediment) and aqueous extract bioassays (sea water elutriates) using the sublethal toxicitymore » test bivalve embryo bioassay (Crassostrea gigas). Elutriates enable them to detect the toxicity of contaminants which may be released in the soluble form into the water column during dredging operations. While, whole sediment integrate the synergistic effects of all the contaminants (hydrophilic and hydrophobic) including pore water. Bioassays results, correlated to chemical analysis, are compared to contaminant levels determined by French working group GEODE and Canadian sediment quality criteria.« less

  10. Hanford internal dosimetry program manual

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, E.H.; Sula, M.J.; Bihl, D.E.

    1989-10-01

    This document describes the Hanford Internal Dosimetry program. Program Services include administrating the bioassay monitoring program, evaluating and documenting assessments of internal exposure and dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating internal radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. 13 refs., 16 figs., 42 tabs.

  11. The use of genetically modified mice in cancer risk assessment: challenges and limitations.

    PubMed

    Eastmond, David A; Vulimiri, Suryanarayana V; French, John E; Sonawane, Babasaheb

    2013-09-01

    The use of genetically modified (GM) mice to assess carcinogenicity is playing an increasingly important role in the safety evaluation of chemicals. While progress has been made in developing and evaluating mouse models such as the Trp53⁺/⁻, Tg.AC and the rasH2, the suitability of these models as replacements for the conventional rodent cancer bioassay and for assessing human health risks remains uncertain. The objective of this research was to evaluate the use of accelerated cancer bioassays with GM mice for assessing the potential health risks associated with exposure to carcinogenic agents. We compared the published results from the GM bioassays to those obtained in the National Toxicology Program's conventional chronic mouse bioassay for their potential use in risk assessment. Our analysis indicates that the GM models are less efficient in detecting carcinogenic agents but more consistent in identifying non-carcinogenic agents. We identified several issues of concern related to the design of the accelerated bioassays (e.g., sample size, study duration, genetic stability and reproducibility) as well as pathway-dependency of effects, and different carcinogenic mechanisms operable in GM and non-GM mice. The use of the GM models for dose-response assessment is particularly problematic as these models are, at times, much more or less sensitive than the conventional rodent cancer bioassays. Thus, the existing GM mouse models may be useful for hazard identification, but will be of limited use for dose-response assessment. Hence, caution should be exercised when using GM mouse models to assess the carcinogenic risks of chemicals.

  12. The usefulness of a sediment bioassay with the gastropod Nassarius reticulatus in tributyltin monitoring programs.

    PubMed

    Laranjeiro, Filipe; Pérez, Sara; Navarro, Patricia; Carrero, José Antonio; Beiras, Ricardo

    2015-11-01

    Despite the use of tributyltin (TBT) had been banned worldwide in 2008 there is still evidence of its deleterious presence in environment. We evaluate the usefulness of a 28days sediment bioassay with Nassarius reticulatus females to monitor TBT pollution, using imposex as endpoint. In addition, butyltins were determined in sediments and tissues, and, whenever posible, imposex was assessed in native N. reticulatus at the same sites where sediments were sampled. In the bioassay, a significant increase in imposex parameters was obtained with three sediments (Vi2, Vi3, and Vi4). No correlation was found between this and TBT concentrations in sediment although good correlations were obtained for TBT in tissues, putting in evidence TBT bioavailability in sediment. A significant decrease in imposex from 2008 to 2013 in native snails was only observed at sites that did not cause any effect in the bioassay. In contrast, imposex levels in 2013 were kept as high as 2008 in one of the sites where a significant imposex increase in the bioassay was observed. The bioassay proves thus to be a practical and ecological relevant tool, as: (i) it can be conducted in sites with no native populations of snails, (ii) it provides early identification of polluted sites, anticipating future imposex levels or early identification of recovering, and (iii) it yields information on the bioavailable fraction of the TBT in the sediment. Therefore, this tool can be of extreme usefulness under the scope of recent European legislative frameworks. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. ADMAP (automatic data manipulation program)

    NASA Technical Reports Server (NTRS)

    Mann, F. I.

    1971-01-01

    Instructions are presented on the use of ADMAP, (automatic data manipulation program) an aerospace data manipulation computer program. The program was developed to aid in processing, reducing, plotting, and publishing electric propulsion trajectory data generated by the low thrust optimization program, HILTOP. The program has the option of generating SC4020 electric plots, and therefore requires the SC4020 routines to be available at excution time (even if not used). Several general routines are present, including a cubic spline interpolation routine, electric plotter dash line drawing routine, and single parameter and double parameter sorting routines. Many routines are tailored for the manipulation and plotting of electric propulsion data, including an automatic scale selection routine, an automatic curve labelling routine, and an automatic graph titling routine. Data are accepted from either punched cards or magnetic tape.

  14. Cryopreserved Human Precision-Cut Lung Slices as a Bioassay for Live Tissue Banking. A Viability Study of Bronchodilation with Bitter-Taste Receptor Agonists

    PubMed Central

    Bai, Yan; Krishnamoorthy, Nandini; Patel, Kruti R.; Rosas, Ivan; Ai, Xingbin

    2016-01-01

    Human precision-cut lung slices (hPCLSs) provide a unique ex vivo model for translational research. However, the limited and unpredictable availability of human lung tissue greatly impedes their use. Here, we demonstrate that cryopreservation of hPCLSs facilitates banking of live human lung tissue for routine use. Our results show that cryopreservation had little effect on overall cell viability and vital functions of immune cells, including phagocytes and T lymphocytes. In addition, airway contraction and relaxation in response to specific agonists and antagonists, respectively, were unchanged after cryopreservation. At the subcellular level, cryopreserved hPCLSs maintained Ca2+-dependent regulatory mechanisms for the control of airway smooth muscle cell contractility. To exemplify the use of cryopreserved hPCLSs in smooth muscle research, we provide evidence that bitter-taste receptor (TAS2R) agonists relax airways by blocking Ca2+ oscillations in airway smooth muscle cells. In conclusion, the banking of cryopreserved hPCLSs provides a robust bioassay for translational research of lung physiology and disease. PMID:26550921

  15. AN INTERLABORATORY COMPARISON ON THE DETERMINATION OF 241Am, 244Cm AND 252Cf IN URINE.

    PubMed

    Gerstmann, Udo C; Taubner, Kerstin; Hartmann, Martina

    2016-09-01

    An intercomparison exercise on the determination of (241)Am, (244)Cm and (252)Cf in urine was performed. Since it was designed with regard to emergency preparedness, the detection limit for each nuclide was set to 0.1 Bq per 24-h urine sample. Most of the participating laboratories were established bioassay laboratories. However, some laboratories that routinely determine (241)Am only in environmental samples were also invited in order to explore their potential for emergency bioassay analysis. Another aspect of the intercomparison was to investigate the performance of all laboratories concerning the chemical yields of the (243)Am tracer in comparison with (244)Cm and (252)Cf. In summary, both types of laboratories showed good results. There was a negative bias for the results of (244)Cm and (252)Cf, which can be explained by slightly different radiochemical behaviours of americium, curium and californium and which is in agreement with results reported in the literature. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Cryopreserved Human Precision-Cut Lung Slices as a Bioassay for Live Tissue Banking. A Viability Study of Bronchodilation with Bitter-Taste Receptor Agonists.

    PubMed

    Bai, Yan; Krishnamoorthy, Nandini; Patel, Kruti R; Rosas, Ivan; Sanderson, Michael J; Ai, Xingbin

    2016-05-01

    Human precision-cut lung slices (hPCLSs) provide a unique ex vivo model for translational research. However, the limited and unpredictable availability of human lung tissue greatly impedes their use. Here, we demonstrate that cryopreservation of hPCLSs facilitates banking of live human lung tissue for routine use. Our results show that cryopreservation had little effect on overall cell viability and vital functions of immune cells, including phagocytes and T lymphocytes. In addition, airway contraction and relaxation in response to specific agonists and antagonists, respectively, were unchanged after cryopreservation. At the subcellular level, cryopreserved hPCLSs maintained Ca(2+)-dependent regulatory mechanisms for the control of airway smooth muscle cell contractility. To exemplify the use of cryopreserved hPCLSs in smooth muscle research, we provide evidence that bitter-taste receptor (TAS2R) agonists relax airways by blocking Ca(2+) oscillations in airway smooth muscle cells. In conclusion, the banking of cryopreserved hPCLSs provides a robust bioassay for translational research of lung physiology and disease.

  17. Diagnostic doses and times for Phlebotomus papatasi and Lutzomyia longipalpis sand flies (Diptera: Psychodidae: Phlebotominae) using the CDC bottle bioassay to assess insecticide resistance.

    PubMed

    Denlinger, David S; Creswell, Joseph A; Anderson, J Laine; Reese, Conor K; Bernhardt, Scott A

    2016-04-15

    Insecticide resistance to synthetic chemical insecticides is a worldwide concern in phlebotomine sand flies (Diptera: Psychodidae), the vectors of Leishmania spp. parasites. The CDC bottle bioassay assesses resistance by testing populations against verified diagnostic doses and diagnostic times for an insecticide, but the assay has been used limitedly with sand flies. The objective of this study was to determine diagnostic doses and diagnostic times for laboratory Lutzomyia longipalpis (Lutz & Nieva) and Phlebotomus papatasi (Scopoli) to ten insecticides, including pyrethroids, organophosphates, carbamates, and DDT, that are used worldwide to control vectors. Bioassays were conducted in 1,000-ml glass bottles each containing 10-25 sand flies from laboratory colonies of L. longipalpis or P. papatasi. Four pyrethroids, three organophosphates, two carbamates and one organochlorine, were evaluated. A series of concentrations were tested for each insecticide, and four replicates were conducted for each concentration. Diagnostic doses were determined only during the exposure bioassay for the organophosphates and carbamates. For the pyrethroids and DDT, diagnostic doses were determined for both the exposure bioassay and after a 24-hour recovery period. Both species are highly susceptible to the carbamates as their diagnostic doses are under 7.0 μg/ml. Both species are also highly susceptible to DDT during the exposure assay as their diagnostic doses are 7.5 μg/ml, yet their diagnostic doses for the 24-h recovery period are 650.0 μg/ml for Lu. longipalpis and 470.0 μg/ml for P. papatasi. Diagnostic doses and diagnostic times can now be incorporated into vector management programs that use the CDC bottle bioassay to assess insecticide resistance in field populations of Lu. longipalpis and P. papatasi. These findings provide initial starting points for determining diagnostic doses and diagnostic times for other sand fly vector species and wild populations using the CDC bottle bioassay.

  18. Overview of results from the WaterTox intercalibration and environmental testing phase II program: part 2, ecotoxicological evaluation of drinking water supplies.

    PubMed

    Diaz-Baez, M C; Sánchez, W A; Dutka, B J; Ronco, A; Castillo, G; Pica-Granados, Y; Castillo, L E; Ridal, J; Arkhipchuk, V; Srivastava, R C

    2002-01-01

    Because of rapid population growth, industrial development, and intensified agricultural production increasing amounts of chemicals are being released into the environment, polluting receiving water bodies around the world. Given the potential health risk associated with the presence of toxicants in water sources used for drinking yet the scarcity of available data, there is a need to evaluate these waters and develop strategies to reduce and prevent their contamination. The present study examined the applicability of a battery of simple, inexpensive bioassays in environmental management and the relevance of the test results in establishing the toxicological quality of water sources and drinking water within the framework of the eight-country WaterTox Network, sponsored by the International Development Research Centre, Ottawa, Canada. Seventy-six samples were collected from surface and groundwater sources and seven samples from drinking water treatment plants. Each sample was tested with a core battery of bioassays (Daphnia magna, Hydra attenuata, and Lactuca sativa root inhibition tests) and a limited set of physical and chemical parameters. In addition, three labs included the Selenastrum capricornutum test. When no toxic effects were found with the battery, samples were concentrated 10x using a solid-phase extraction (SPE) procedure. Nonconcentrated natural water samples produced a toxic response in 24% of cases with all three core bioassays. When all bioassays are considered, the percentage of raw samples showing toxicity with at least one bioassay increased to 60%. Of seven treated drinkingwater samples, four showed toxicity with at least one bioassay, raising the possibility that treatment processes in these instances were unable to remove toxic contaminants. The Daphnia magna and Hydra attenuata tests indicated a high level of sensitivity overall. Although only three of the eight countries used S. capricornutum, it proved to be an efficient and reliable bioassay for toxicity assessment. Copyright 2002 Wiley Periodicals, Inc.

  19. Advantages and Limitations of Androgen Receptor-Based Methods for Detecting Anabolic Androgenic Steroid Abuse as Performance Enhancing Drugs.

    PubMed

    Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred

    2016-01-01

    Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete's urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as 'T-equivalent' concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact.

  20. DOSESCREEN: a computer program to aid dose placement

    Treesearch

    Kimberly C. Smith; Jacqueline L. Robertson

    1984-01-01

    Careful selection of an experimental design for a bioassay substantially improves the precision of effective dose (ED) estimates. Design considerations typically include determination of sample size, dose selection, and allocation of subjects to doses. DOSESCREEN is a computer program written to help investigators select an efficient design for the estimation of an...

  1. Gender differences in chemical carcinogenesis in National Toxicology Program two-year bioassays

    PubMed Central

    Kadekar, Sandeep; Peddada, Shyamal; Silins, Ilona; French, John E; Högberg, Johan; Stenius, Ulla

    2016-01-01

    Differences in cancer incidences between men and women are often explained by either differences in environmental exposures or by influences of sex hormones. However, there are few studies on intrinsic gender differences in susceptibility to chemical carcinogens. We have analyzed the National Toxicology Program (NTP) database for sex differences in rat responses to chemical carcinogens. We find that the odds that male rat bioassays were assigned a higher level of evidence than female rat bioassays was 1.69 (p<0.001). Of 278 carcinogenic chemicals in the database, 201 (72%) exhibited statistical gender differences (p = 0.05) in at least one non-reproductive organ. 130 of these 201 chemicals induced gender-specific tumors in male rats and 59 in female rats. 68 chemicals induced tumors in males but no tumors in females. Less than one third, i.e. 19 chemicals, induced tumors in females but not males. Male-specific tumors included pancreatic tumor and skin tumor, and female-specific tumors included lung tumors. For some tumor types these differences in gender susceptibility can be associated with literature data on sex hormone receptor expression. In conclusion, gender-specific tumors were common. The male dominance is in line with human data and the male susceptibility to carcinogens should be further studied. PMID:22585941

  2. Determination, mechanism and monitoring of knockdown resistance in permethrin-resistant human head lice, Pediculus humanus capitis

    PubMed Central

    Clark, J. Marshall

    2009-01-01

    Permethrin resistance has been reported worldwide and clinical failures to commercial pediculicides containing permethrin have likewise occurred. Permethrin resistance in head lice populations from the U.S. is widespread but is not yet uniform and the level of resistance is relatively low (~4–8 fold). Permethrin-resistant lice are cross-resistant to pyrethrins, PBO-synergized pyrethrins and to DDT. Nix®, when applied to human hair tufts following manufacture’s instructions, did not provide 100% control when assessed by the hair tuft bioassay in conjunction with the in vitro rearing system. Resistance to permethrin is due to knockdown resistance (kdr), which is the result of three point mutations within the α-subunit gene of the voltage-gated sodium channel that causes amino acid substitutions, leading to nerve insensitivity. A three-tiered resistance monitoring system has been established based on molecular resistance detection techniques. Quantitative sequencing (QS) has been developed to predict the kdr allele frequency in head lice at a population level. The speed, simplicity and accuracy of QS made it an ideal candidate for a routine primary resistance monitoring tool to screen a large number of louse populations as an alternative to conventional bioassay. As a secondary monitoring method, real-time PASA (rtPASA) has been devised for a more precise determination of low resistance allele frequencies. To obtain more detailed information on resistance allele zygosity, as well as allele frequency, serial invasive signal amplification reaction (SISAR) has been developed as an individual genotyping method. Our approach of using three tiers of molecular resistance detection should facilitate large-scale routine resistance monitoring of permethrin resistance in head lice using field-collected samples. PMID:20161186

  3. Scrubchem: Building Bioactivity Datasets from Pubchem ...

    EPA Pesticide Factsheets

    The PubChem Bioassay database is a non-curated public repository with data from 64 sources, including: ChEMBL, BindingDb, DrugBank, EPA Tox21, NIH Molecular Libraries Screening Program, and various other academic, government, and industrial contributors. Methods for extracting this public data into quality datasets, useable for analytical research, presents several big-data challenges for which we have designed manageable solutions. According to our preliminary work, there are approximately 549 million bioactivity values and related meta-data within PubChem that can be mapped to over 10,000 biological targets. However, this data is not ready for use in data-driven research, mainly due to lack of structured annotations.We used a pragmatic approach that provides increasing access to bioactivity values in the PubChem Bioassay database. This included restructuring of individual PubChem Bioassay files into a relational database (ScrubChem). ScrubChem contains all primary PubChem Bioassay data that was: reparsed; error-corrected (when applicable); enriched with additional data links from other NCBI databases; and improved by adding key biological and assay annotations derived from logic-based language processing rules. The utility of ScrubChem and the curation process were illustrated using an example bioactivity dataset for the androgen receptor protein. This initial work serves as a trial ground for establishing the technical framework for accessing, integrating, cu

  4. The OECD program to validate the rat uterotrophic bioassay to screen compounds for in vivo estrogenic responses: phase 1.

    PubMed Central

    Kanno, J; Onyon, L; Haseman, J; Fenner-Crisp, P; Ashby, J; Owens, W

    2001-01-01

    The Organisation for Economic Co-operation and Development has completed the first phase of an international validation program for the rodent uterotrophic bioassay. This uterotrophic bioassay is intended to identify the in vivo activity of compounds that are suspected agonists or antagonists of estrogen. This information could, for example, be used to help prioritize positive compounds for further testing. Using draft protocols, we tested and compared two model systems, the immature female rat and the adult ovariectomized rat. Data from 19 participating laboratories using a high-potency reference agonist, ethinyl estradiol (EE), and an antagonist, ZM 189,154, indicate no substantive performance differences between models. All laboratories and all protocols successfully detected increases in uterine weights using EE in phase 1. These significant uterine weight increases were achieved under a variety of experimental conditions (e.g., strain, diet, housing protocol, bedding, vehicle). For each protocol, there was generally good agreement among laboratories with regard to the actual EE doses both in producing the first significant increase in uterine weights and achieving the maximum uterine response. Furthermore, the Hill equation appears to model the dose response satisfactorily and indicates general agreement based on calculated effective dose (ED)(10) and ED(50) within and among laboratories. The feasibility of an antagonist assay was also successfully demonstrated. Therefore, both models appear robust, reproducible, and transferable across laboratories for high-potency estrogen agonists such as EE. For the next phase of the OECD validation program, both models will be tested against a battery of weak, partial estrogen agonists. PMID:11564613

  5. A new effective assay to detect antimicrobial activity of filamentous fungi.

    PubMed

    Pereira, Eric; Santos, Ana; Reis, Francisca; Tavares, Rui M; Baptista, Paula; Lino-Neto, Teresa; Almeida-Aguiar, Cristina

    2013-01-15

    The search for new antimicrobial compounds and the optimization of production methods turn the use of antimicrobial susceptibility tests a routine. The most frequently used methods are based on agar diffusion assays or on dilution in agar or broth. For filamentous fungi, the most common antimicrobial activity detection methods comprise the co-culture of two filamentous fungal strains or the use of fungal extracts to test against single-cell microorganisms. Here we report a rapid, effective and reproducible assay to detect fungal antimicrobial activity against single-cell microorganisms. This method allows an easy way of performing a fast antimicrobial screening of actively growing fungi directly against yeast. Because it makes use of an actively growing mycelium, this bioassay also provides a way for studying the production dynamics of antimicrobial compounds by filamentous fungi. The proposed assay is less time consuming and introduces the innovation of allowing the direct detection of fungal antimicrobial properties against single cell microorganisms without the prior isolation of the active substance(s). This is particularly useful when performing large screenings for fungal antimicrobial activity. With this bioassay, antimicrobial activity of Hypholoma fasciculare against yeast species was observed for the first time. Copyright © 2012 Elsevier GmbH. All rights reserved.

  6. 42 CFR 493.931 - Routine chemistry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  7. 42 CFR 493.931 - Routine chemistry.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 5 2013-10-01 2013-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  8. 42 CFR 493.931 - Routine chemistry.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 5 2012-10-01 2012-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  9. 42 CFR 493.931 - Routine chemistry.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  10. 42 CFR 493.931 - Routine chemistry.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 5 2011-10-01 2011-10-01 false Routine chemistry. 493.931 Section 493.931 Public... Proficiency Testing Programs by Specialty and Subspecialty § 493.931 Routine chemistry. (a) Program content and frequency of challenge. To be approved for proficiency testing for routine chemistry, a program...

  11. Hanford Internal Dosimetry Program Manual, PNL-MA-552

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.

    2009-09-24

    This manual is a guide to the services provided by the Hanford Internal Dosimetry Program (IDP), which is operated by the Pacific Northwest National Laboratory.( ) for the U.S. Department of Energy Richland Operations Office, Office of River Protection and their Hanford Site contractors. The manual describes the roles of and relationships between the IDP and the radiation protection programs of the Hanford Site contractors. Recommendations and guidance are also provided for consideration in implementing bioassay monitoring and internal dosimetry elements of radiation protection programs.

  12. Isolation and quantification of botulinum neurotoxin from complex matrices using the BoTest matrix assays.

    PubMed

    Dunning, F Mark; Piazza, Timothy M; Zeytin, Füsûn N; Tucker, Ward C

    2014-03-03

    Accurate detection and quantification of botulinum neurotoxin (BoNT) in complex matrices is required for pharmaceutical, environmental, and food sample testing. Rapid BoNT testing of foodstuffs is needed during outbreak forensics, patient diagnosis, and food safety testing while accurate potency testing is required for BoNT-based drug product manufacturing and patient safety. The widely used mouse bioassay for BoNT testing is highly sensitive but lacks the precision and throughput needed for rapid and routine BoNT testing. Furthermore, the bioassay's use of animals has resulted in calls by drug product regulatory authorities and animal-rights proponents in the US and abroad to replace the mouse bioassay for BoNT testing. Several in vitro replacement assays have been developed that work well with purified BoNT in simple buffers, but most have not been shown to be applicable to testing in highly complex matrices. Here, a protocol for the detection of BoNT in complex matrices using the BoTest Matrix assays is presented. The assay consists of three parts: The first part involves preparation of the samples for testing, the second part is an immunoprecipitation step using anti-BoNT antibody-coated paramagnetic beads to purify BoNT from the matrix, and the third part quantifies the isolated BoNT's proteolytic activity using a fluorogenic reporter. The protocol is written for high throughput testing in 96-well plates using both liquid and solid matrices and requires about 2 hr of manual preparation with total assay times of 4-26 hr depending on the sample type, toxin load, and desired sensitivity. Data are presented for BoNT/A testing with phosphate-buffered saline, a drug product, culture supernatant, 2% milk, and fresh tomatoes and includes discussion of critical parameters for assay success.

  13. TOXICITY TESTING, RISK ASSESSMENT, AND OPTIONS FOR DREDGED MATERIAL MANAGEMENT

    EPA Science Inventory

    Programs for evaluating proposed discharges of dredged material into waters of the United States specify a tiered testing and evaluation protocol that includes performance of acute and chronic bioassays to assess toxicity of the dredged sediments. Although these evaluations refl...

  14. SCIENTIFIC FOUNDATION FOR RISK ASSESSMENTS TO PROTECT NON-TARGET PLANTS FROM HERBICIDES

    EPA Science Inventory

    SCIENCE QUESTIONS:

    EPA's Office of Pesticides Programs (OPP) requires scientifically credible information and methods to assess health and ecological risks from chemical pesticides. However the suite of standard bioassays and approaches available to OPP to determine these ...

  15. Bioassay- versus analytically-derived estrogen equivalents: Ramifications for monitoring

    EPA Science Inventory

    Due to concern for possible endocrine-related effects on aquatic vertebrates, environmental estrogens (EEs) are a growing focus of surface water contaminant monitoring programs. Some efforts utilize measurement of a targeted set of chemicals known to act as estrogen receptor (ER)...

  16. System design of a remotely operated, program controlled measurement table for the calibration of the Egret experiment. Part A: Program control

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The structure of the program, the five priority levels, the drive routines, the stepwise drive plan, the figure routines, meander X and y, the range of measurement table, the optimization of figure drive, the figure drive plan, dialogue routines, stack processing, the drive for the main terminal, the protocol routines, the drive for the microterminal, the drive for the experiment computer, and the main program are discussed.

  17. Exploration of ToxCast/Tox21 bioassays as candidate bioanalytical tools for measuring groups of chemicals in water.

    PubMed

    Louisse, Jochem; Dingemans, Milou M L; Baken, Kirsten A; van Wezel, Annemarie P; Schriks, Merijn

    2018-06-14

    The present study explores the ToxCast/Tox21 database to select candidate bioassays as bioanalytical tools for measuring groups of chemicals in water. To this aim, the ToxCast/Tox21 database was explored for bioassays that detect polycyclic aromatic hydrocarbons (PAHs), aromatic amines (AAs), (chloro)phenols ((C)Ps) and halogenated aliphatic hydrocarbons (HAliHs), which are included in the European and/or Dutch Drinking Water Directives. Based on the analysis of the availability and performance of bioassays included in the database, we concluded that several bioassays are suitable as bioanalytical tools for assessing the presence of PAHs and (C)Ps in drinking water sources. No bioassays were identified for AAs and HAliHs, due to the limited activity of these chemicals and/or the limited amount of data on these chemicals in the database. A series of bioassays was selected that measure molecular or cellular effects that are covered by bioassays currently in use for chemical water quality monitoring. Interestingly, also bioassays were selected that represent molecular or cellular effects that are not covered by bioassays currently applied. The usefulness of these newly identified bioassays as bioanalytical tools should be further evaluated in follow-up studies. Altogether, this study shows how exploration of the ToxCast/Tox21 database provides a series of candidate bioassays as bioanalytical tools for measuring groups of chemicals in water. This assessment can be performed for any group of chemicals of interest (if represented in the database), and may provide candidate bioassays that can be used to complement the currently applied bioassays for chemical water quality assessment. Copyright © 2018. Published by Elsevier Ltd.

  18. Bioactive contaminants leach from disposable laboratory plasticware.

    PubMed

    McDonald, G Reid; Hudson, Alan L; Dunn, Susan M J; You, Haitao; Baker, Glen B; Whittal, Randy M; Martin, Jonathan W; Jha, Amitabh; Edmondson, Dale E; Holt, Andrew

    2008-11-07

    Disposable plasticware such as test tubes, pipette tips, and multiwell assay or culture plates are used routinely in most biological research laboratories. Manufacturing of plastics requires the inclusion of numerous chemicals to enhance stability, durability, and performance. Some lubricating (slip) agents, exemplified by oleamide, also occur endogenously in humans and are biologically active, and cationic biocides are included to prevent bacterial colonization of the plastic surface. We demonstrate that these manufacturing agents leach from laboratory plasticware into a standard aqueous buffer, dimethyl sulfoxide, and methanol and can have profound effects on proteins and thus on results from bioassays of protein function. These findings have far-reaching implications for the use of disposable plasticware in biological research.

  19. FPT- FORTRAN PROGRAMMING TOOLS FOR THE DEC VAX

    NASA Technical Reports Server (NTRS)

    Ragosta, A. E.

    1994-01-01

    The FORTRAN Programming Tools (FPT) are a series of tools used to support the development and maintenance of FORTRAN 77 source codes. Included are a debugging aid, a CPU time monitoring program, source code maintenance aids, print utilities, and a library of useful, well-documented programs. These tools assist in reducing development time and encouraging high quality programming. Although intended primarily for FORTRAN programmers, some of the tools can be used on data files and other programming languages. BUGOUT is a series of FPT programs that have proven very useful in debugging a particular kind of error and in optimizing CPU-intensive codes. The particular type of error is the illegal addressing of data or code as a result of subtle FORTRAN errors that are not caught by the compiler or at run time. A TRACE option also allows the programmer to verify the execution path of a program. The TIME option assists the programmer in identifying the CPU-intensive routines in a program to aid in optimization studies. Program coding, maintenance, and print aids available in FPT include: routines for building standard format subprogram stubs; cleaning up common blocks and NAMELISTs; removing all characters after column 72; displaying two files side by side on a VT-100 terminal; creating a neat listing of a FORTRAN source code including a Table of Contents, an Index, and Page Headings; converting files between VMS internal format and standard carriage control format; changing text strings in a file without using EDT; and replacing tab characters with spaces. The library of useful, documented programs includes the following: time and date routines; a string categorization routine; routines for converting between decimal, hex, and octal; routines to delay process execution for a specified time; a Gaussian elimination routine for solving a set of simultaneous linear equations; a curve fitting routine for least squares fit to polynomial, exponential, and sinusoidal forms (with a screen-oriented editor); a cubic spline fit routine; a screen-oriented array editor; routines to support parsing; and various terminal support routines. These FORTRAN programming tools are written in FORTRAN 77 and ASSEMBLER for interactive and batch execution. FPT is intended for implementation on DEC VAX series computers operating under VMS. This collection of tools was developed in 1985.

  20. Exploring the potential utility of high-throughput bioassays associated with US EPA Toxcast Program for effects-based monitoring and surveillance

    EPA Science Inventory

    Environmental monitoring and surveillance strategies are essential for identifying potential hazards of contaminant exposure to aquatic organisms. Chemical monitoring is effective for chemicals with well characterized hazards and for which sensitive analytical methods are availa...

  1. A MAP read-routine for IBM 7094 Fortran II binary tapes

    Treesearch

    Robert S. Helfman

    1966-01-01

    Two MAP (Macro Assembly Program) language routines are descrived. They permit Fortran IV programs to read binary tapes generated by Fortran II programs, on the IBM 7090 and 7094 computers. One routine is for use with 7040/44-IBSYS, the other for 7090/94-IBSYS.

  2. [Investigation on pattern and methods of quality control for Chinese materia medica based on dao-di herbs and bioassay - bioassay for Coptis chinensis].

    PubMed

    Yan, Dan; Xiao, Xiao-he

    2011-05-01

    Establishment of bioassay methods is the technical issues to be faced with in the bioassay of Chinese materia medica. Taking the bioassay of Coptis chinensis Franch. as an example, the establishment process and application of the bioassay methods (including bio-potency and bio-activity fingerprint) were explained from the aspects of methodology, principle of selection, experimental design, method confirmation and data analysis. The common technologies were extracted and formed with the above aspects, so as to provide technical support for constructing pattern and method of the quality control for Chinese materia medica based on the dao-di herbs and bioassay.

  3. Cancer-Specific Stress and Mood Disturbance: Implications for Symptom Perception, Quality of Life, and Immune Response in Women Shortly after Diagnosis of Breast Cancer

    PubMed Central

    Kang, Duck-Hee; Park, Na-Jin; McArdle, Traci

    2012-01-01

    Purpose. To determine the levels of cancer-specific stress and mood disturbance in women shortly after diagnosis of breast cancer and to assess their associations with symptom perception, quality of life, and immune response. Design. Descriptive and correlational. Sample and Setting. One hundred women with newly diagnosed breast cancer were recruited from interdisciplinary breast clinics. Methods. Baseline data were collected using standardized questionnaires and established bioassay prior to the initiation of cancer adjuvant therapy. Blood samples were collected about the same time of day. Results. High cancer-specific stress was significantly correlated with high mood disturbance, which, in turn, was correlated with high symptom perception, poor quality of life, and an immune profile indicating high neutrophils and low lymphocytes. Conclusions. High cancer-specific stress and related mood disturbance show extensive negative relationships with multiple behavioral, clinical, and biological factors. Implications for Nursing. Routine screening for cancer-related stress and mood disturbance should be incorporated into nursing practice for all patients diagnosed with cancer. Given broad negative associations with other biobehavioral factors, early identification of patients at risk and provision and evaluation of stress and mood management programs may have a beneficial effect on subsequent health outcomes over time. PMID:23316388

  4. DB90: A Fortran Callable Relational Database Routine for Scientific and Engineering Computer Programs

    NASA Technical Reports Server (NTRS)

    Wrenn, Gregory A.

    2005-01-01

    This report describes a database routine called DB90 which is intended for use with scientific and engineering computer programs. The software is written in the Fortran 90/95 programming language standard with file input and output routines written in the C programming language. These routines should be completely portable to any computing platform and operating system that has Fortran 90/95 and C compilers. DB90 allows a program to supply relation names and up to 5 integer key values to uniquely identify each record of each relation. This permits the user to select records or retrieve data in any desired order.

  5. Utilizing high-throughput bioassays associated with US EPA ToxCast Program to assess biological activity of environmental contaminants: A case study of chemical mixtures

    EPA Science Inventory

    Effects-based monitoring and surveillance is increasingly being utilized in conjunction with chemical monitoring to determine potential biological activity associated with environmental contaminants. Supervised approaches targeting specific chemical activity or molecular pathways...

  6. Comparative efficacy of selected insecticide alternatives for boll weevil (Coleoptera: Curculionidae) control using laboratory bioassays

    USDA-ARS?s Scientific Manuscript database

    The boll weevil, Anthonomus grandis grandis (Boheman), is a major cotton pest responsible for an estimated $300 million in annual crop losses. Boll weevil eradication programs depend on malathion ULV to achieve and maintain eradication status. Should this effective and economical insecticide become ...

  7. Differentiating pathway-specific from nonspecific effects in high-throughput toxicity data: A foundation for prioritizing adverse outcome pathway development

    EPA Science Inventory

    The U.S. Environmental Protection Agency’s ToxCast program has screened thousands of chemicals for biological activity, primarily using high-throughput in vitro bioassays. Adverse outcome pathways (AOPs) offer a means to link pathway-specific biological activities with potential ...

  8. POLO: a user's guide to Probit Or LOgit analysis.

    Treesearch

    Jacqueline L. Robertson; Robert M. Russell; N.E. Savin

    1980-01-01

    This user's guide provides detailed instructions for the use of POLO (Probit Or LOgit), a computer program for the analysis of quantal response data such as that obtained from insecticide bioassays by the techniques of probit or logit analysis. Dosage-response lines may be compared for parallelism or...

  9. TOXICITY TRENDS DURING AN OIL SPILL BIOREMEDIATION EXPERIMENT ON A SANDY SHORELINE IN DELAWARE, USA

    EPA Science Inventory

    A 13-week, refereed, inter-agency toxicity testing program involving five bioassay methods was used to document the effectiveness of shoreline bioremediation to accelerate toxicity reduction of an oiled sandy shoreline at Fowler Beach, Delaware, USA. The study was part of an inte...

  10. Critical review and evaluation of the uterotrophic bioassay for the identification of possible estrogen agonists and antagonists: in support of the validation of the OECD uterotrophic protocols for the laboratory rodent. Organisation for Economic Co-operation and Development.

    PubMed

    Owens, J William; Ashby, John

    2002-01-01

    A current issue for regulatory agencies is endocrine-related modes of action such as those mediated by the estrogen, androgen, and thyroid nuclear receptors. At the national and international levels, the consensus recommendation for the assessment of such modes of action is a tiered series of in vitro and in vivo protocols. The tiered framework begins with screens for structural alerts and then moves to rapid, mechanistic in vitro screening assays, and then to in vivo screening bioassays. The objective of these screens is to identify substances that may warrant testing for endocrine-mediated adverse effects. The final framework tier as needed is to test these substances in long-term bioassays for adverse endocrine-mediated reproductive and/or developmental effects. The subject of this review, the rodent uterotrophic bioassay, is intended to be a rapid in vivo screening bioassay for possible estrogen agonists and based on the response of the estrogen-sensitive uterus. The central metric of bioassay is a statistically significant increase in the weight of the uterus after 3 consecutive days of test substance administration. The extensive background literature is summarized in this review on the mode of action underlying the bioassay and the uterine response to estrogens. The review includes the bioassay's history of development and how its employment has changed and evolved over time. The review describes two major uterotrophic bioassay versions, the intact, immature female and the mature, ovariectomized female, and the protocol factors likely to influence relevance, reproducibility, and reliability of bioassay. The emphasis of the review is the ability of the uterotrophic bioassay to identify the substances of current interest: weak estrogen agonists with binding affinities relative to the natural 17beta-estradiol in the log 0 to log -3 range. Using selected model substances having RBAs in this target range, the bioassay's performance in a hierarchical, tiered approach is evaluated, including the predictive capability of the uterotrophic bioassay based on available reproductive and developmental testing data. The review concludes that the uterotrophic bioassay is reliable and can identify substances that may act via an estrogen-mode of action, supporting the validity of the uterotrophic bioassay and its regulatory use as an in vivo mechanistic screening bioassay for estrogen agonists and antagonists.

  11. Airline return-on-investment model for technology evaluation. [computer program to measure economic value of advanced technology applied to passenger aircraft

    NASA Technical Reports Server (NTRS)

    1974-01-01

    This report presents the derivation, description, and operating instructions for a computer program (TEKVAL) which measures the economic value of advanced technology features applied to long range commercial passenger aircraft. The program consists of three modules; and airplane sizing routine, a direct operating cost routine, and an airline return-on-investment routine. These modules are linked such that they may be operated sequentially or individually, with one routine generating the input for the next or with the option of externally specifying the input for either of the economic routines. A very simple airplane sizing technique was previously developed, based on the Brequet range equation. For this program, that sizing technique has been greatly expanded and combined with the formerly separate DOC and ROI programs to produce TEKVAL.

  12. Potential biological targets for bioassay development in drug discovery of Sturge-Weber syndrome.

    PubMed

    Mohammadipanah, Fatemeh; Salimi, Fatemeh

    2018-02-01

    Sturge-Weber Syndrome (SWS) is a neurocutaneous disease with clinical manifestations including ocular (glaucoma), cutaneous (port-wine birthmark), neurologic (seizures), and vascular problems. Molecular mechanisms of SWS pathogenesis are initiated by the somatic mutation in GNAQ. Therefore, no definite treatments exist for SWS and treatment options only mitigate the intensity of its clinical manifestations. Biological assay design for drug discovery against this syndrome demands comprehensive knowledge on mechanisms which are involved in its pathogenesis. By analysis of the interrelated molecular targets of SWS, some in vitro bioassay systems can be allotted for drug screening against its progression. Development of such platforms of bioassay can bring along the implementation of high-throughput screening of natural or synthetic compounds in drug discovery programs. Regarding the fact that study of molecular targets and their integration in biological assay design can facilitate the process of effective drug discovery; some potential biological targets and their respective biological assay for SWS drug discovery are propounded in this review. For this purpose, some biological targets for SWS drug discovery such as acetylcholinesterase, alkaline phosphatase, GABAergic receptors, Hypoxia-Inducible Factor (HIF)-1α and 2α are suggested. © 2017 John Wiley & Sons A/S.

  13. Anopheles sinensis mosquito insecticide resistance: comparison of three mosquito sample collection and preparation methods and mosquito age in resistance measurements.

    PubMed

    Xu, Tielong; Zhong, Daibin; Tang, Linhua; Chang, Xuelian; Fu, Fengyang; Yan, Guiyun; Zheng, Bin

    2014-01-28

    Insecticide resistance monitoring in malaria mosquitoes is essential for guiding the rational use of insecticides in vector control programs. Resistance bioassay is the first step for insecticide monitoring and it lays an important foundation for molecular examination of resistance mechanisms. In the literature, various mosquito sample collection and preparation methods have been used, but how mosquito sample collection and preparation methods affect insecticide susceptibility bioassay results is largely unknown. The objectives of this study were to determine whether mosquito sample collection and preparation methods affected bioassay results, which may cause incorrect classification of mosquito resistance status. The study was conducted in Anopheles sinensis mosquitoes in two study sites in central China. Three mosquito sample collection and preparation methods were compared for insecticide susceptibility, kdr frequencies and metabolic enzyme activities: 1) adult mosquitoes collected from the field; 2) F1 adults from field collected, blood-fed mosquitoes; and 3) adult mosquitoes reared from field collected larvae. Mosquito sample collection and preparation methods significantly affected mortality rates in the standard WHO tube resistance bioassay. Mortality rate of field-collected female adults was 10-15% higher than in mosquitoes reared from field-collected larvae and F1 adults from field collected blood-fed females. This pattern was consistent in mosquitoes from the two study sites. High kdr mutation frequency (85-95%) with L1014F allele as the predominant mutation was found in our study populations. Field-collected female adults consistently exhibited the highest monooxygenase and GST activities. The higher mortality rate observed in the field-collected female mosquitoes may have been caused by a mixture of mosquitoes of different ages, as older mosquitoes were more susceptible to deltamethrin than younger mosquitoes. Female adults reared from field-collected larvae in resistance bioassays are recommended to minimize the effect of confounding factors such as mosquito age and blood feeding status so that more reliable and reproducible mortality may be obtained.

  14. [Application of bioassay in quality control of Chinese materia medica-taking Radix Isatidis as an example].

    PubMed

    Yan, Dan; Ren, Yongshen; Luo, Jiaoyang; Li, Hanbing; Feng, Xue; Xiao, Xiaohe

    2010-10-01

    Bioassay, which construct the characteristics consistents with Chinese medical science, is the core mode and methods for the quality control of Chinese materia medica. Taking the bioassay of Radix Isatidis as an example, the contribution, status and application of bioassay in the quality control of Chinese materia medica were introduced in this article, and two key issue (the selection of reference and measurement methods) in the process of establishing bioassay were also explained. This article expects to provide a reference for the development and improvement of the bioassay of Chinese materia medica in a practical manipulation level.

  15. Brine Shrimp Bioassays: A Useful Technique in Biological Investigations

    ERIC Educational Resources Information Center

    Rice, Stanley A.; Maness, Ian B.

    2004-01-01

    A technique to measure the potency of leaf compounds against herbivores with the use of a bioassay is described. Bioassays are useful in classes where students have career plans like medicine in which bioassays can be used as tools for screening plants for possible medicinal potency.

  16. Differentiating pathway-specific from non-specific effects in high-throughput toxicity data: A foundation for prioritizing adverse outcome pathway development

    EPA Science Inventory

    The U.S. Environmental Protection Agency’s ToxCast program has screened thousands of chemicals for biological activity, primarily using high-throughput in vitro bioassays. Adverse outcome pathways (AOPs) offer a means to link pathway-specific biological activities with pote...

  17. Quality control tests of lab-reared Cydia pomonella and Cactoblastis cactorum field performance: Comparison of laboratory and field bioassays.

    USDA-ARS?s Scientific Manuscript database

    Research, operational, and commercial programs which rely on mass-reared insects of high quality and performance, need accurate methods for monitoring quality degradation during each step of production, handling and release. With continued interest in the use of the sterile insect technique (SIT) a...

  18. Circular Bioassay Platforms for Applications in Microwave-Accelerated Techniques.

    PubMed

    Mohammed, Muzaffer; Clement, Travis C; Aslan, Kadir

    2014-12-02

    In this paper, we present the design of four different circular bioassay platforms, which are suitable for homogeneous microwave heating, using theoretical calculations (i.e., COMSOL™ multiphysics software). Circular bioassay platforms are constructed from poly(methyl methacrylate) (PMMA) for optical transparency between 400-800 nm, has multiple sample capacity (12, 16, 19 and 21 wells) and modified with silver nanoparticle films (SNFs) to be used in microwave-accelerated bioassays (MABs). In addition, a small monomode microwave cavity, which can be operated with an external microwave generator (100 W), for use with the bioassay platforms in MABs is also developed. Our design parameters for the circular bioassay platforms and monomode microwave cavity during microwave heating were: (i) temperature profiles, (ii) electric field distributions, (iii) location of the circular bioassay platforms inside the microwave cavity, and (iv) design and number of wells on the circular bioassay platforms. We have also carried out additional simulations to assess the use of circular bioassay platforms in a conventional kitchen microwave oven (e.g., 900 W). Our results show that the location of the circular bioassay platforms in the microwave cavity was predicted to have a significant effect on the homogeneous heating of these platforms. The 21-well circular bioassay platform design in our monomode microwave cavity was predicted to offer a homogeneous heating pattern, where inter-well temperature was observed to be in between 23.72-24.13°C and intra-well temperature difference was less than 0.21°C for 60 seconds of microwave heating, which was also verified experimentally.

  19. Circular Bioassay Platforms for Applications in Microwave-Accelerated Techniques

    PubMed Central

    Mohammed, Muzaffer; Clement, Travis C.; Aslan, Kadir

    2014-01-01

    In this paper, we present the design of four different circular bioassay platforms, which are suitable for homogeneous microwave heating, using theoretical calculations (i.e., COMSOL™ multiphysics software). Circular bioassay platforms are constructed from poly(methyl methacrylate) (PMMA) for optical transparency between 400–800 nm, has multiple sample capacity (12, 16, 19 and 21 wells) and modified with silver nanoparticle films (SNFs) to be used in microwave-accelerated bioassays (MABs). In addition, a small monomode microwave cavity, which can be operated with an external microwave generator (100 W), for use with the bioassay platforms in MABs is also developed. Our design parameters for the circular bioassay platforms and monomode microwave cavity during microwave heating were: (i) temperature profiles, (ii) electric field distributions, (iii) location of the circular bioassay platforms inside the microwave cavity, and (iv) design and number of wells on the circular bioassay platforms. We have also carried out additional simulations to assess the use of circular bioassay platforms in a conventional kitchen microwave oven (e.g., 900 W). Our results show that the location of the circular bioassay platforms in the microwave cavity was predicted to have a significant effect on the homogeneous heating of these platforms. The 21-well circular bioassay platform design in our monomode microwave cavity was predicted to offer a homogeneous heating pattern, where inter-well temperature was observed to be in between 23.72–24.13°C and intra-well temperature difference was less than 0.21°C for 60 seconds of microwave heating, which was also verified experimentally. PMID:25568813

  20. The University of New Mexico Center for Molecular Discovery

    PubMed Central

    Edwards, Bruce S.; Gouveia, Kristine; Oprea, Tudor I.; Sklar, Larry A.

    2015-01-01

    The University of New Mexico Center for Molecular Discovery (UNMCMD) is an academic research center that specializes in discovery using high throughput flow cytometry (HTFC) integrated with virtual screening, as well as knowledge mining and drug informatics. With a primary focus on identifying small molecules that can be used as chemical probes and as leads for drug discovery, it is a central core resource for research and translational activities at UNM that supports implementation and management of funded screening projects as well as “up-front” services such as consulting for project design and implementation, assistance in assay development and generation of preliminary data for pilot projects in support of competitive grant applications. The HTFC platform in current use represents advanced, proprietary technology developed at UNM that is now routinely capable of processing bioassays arrayed in 96-, 384- and 1536-well formats at throughputs of 60,000 or more wells per day. Key programs at UNMCMD include screening of research targets submitted by the international community through NIH’s Molecular Libraries Program; a multi-year effort involving translational partnerships at UNM directed towards drug repurposing - identifying new uses for clinically approved drugs; and a recently established personalized medicine initiative for advancing cancer therapy by the application of “smart” oncology drugs in selected patients based on response patterns of their cancer cells in vitro. UNMCMD discoveries, innovation, and translation have contributed to a wealth of inventions, patents, licenses and publications, as well as startup companies, clinical trials and a multiplicity of domestic and international collaborative partnerships to further the research enterprise. PMID:24409953

  1. The University of New Mexico Center for Molecular Discovery.

    PubMed

    Edwards, Bruce S; Gouveia, Kristine; Oprea, Tudor I; Sklar, Larry A

    2014-03-01

    The University of New Mexico Center for Molecular Discovery (UNMCMD) is an academic research center that specializes in discovery using high throughput flow cytometry (HTFC) integrated with virtual screening, as well as knowledge mining and drug informatics. With a primary focus on identifying small molecules that can be used as chemical probes and as leads for drug discovery, it is a central core resource for research and translational activities at UNM that supports implementation and management of funded screening projects as well as "up-front" services such as consulting for project design and implementation, assistance in assay development and generation of preliminary data for pilot projects in support of competitive grant applications. The HTFC platform in current use represents advanced, proprietary technology developed at UNM that is now routinely capable of processing bioassays arrayed in 96-, 384- and 1536-well formats at throughputs of 60,000 or more wells per day. Key programs at UNMCMD include screening of research targets submitted by the international community through NIH's Molecular Libraries Program; a multi-year effort involving translational partnerships at UNM directed towards drug repurposing - identifying new uses for clinically approved drugs; and a recently established personalized medicine initiative for advancing cancer therapy by the application of "smart" oncology drugs in selected patients based on response patterns of their cancer cells in vitro. UNMCMD discoveries, innovation, and translation have contributed to a wealth of inventions, patents, licenses and publications, as well as startup companies, clinical trials and a multiplicity of domestic and international collaborative partnerships to further the research enterprise.

  2. Users manual for the IMA program. Appendix C: Profile design program listing

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The source code for the Profile Design Program (PDP) for the Impulsive Mission Analysis (IMA) program is divided into several files. In a similar manner, the FORTRAN listings of the PDP's subroutines and function routines are organized into several groups in this appendix. Within each group, the FORTRAN listings are ordered alphabetically by routine name. Names and brief descriptions of each routine are listed in the same order as the Fortran listings.

  3. ESTIMATION OF INTERNAL EXPOSURE TO URANIUM WITH UNCERTAINTY FROM URINALYSIS DATA USING THE InDEP COMPUTER CODE

    PubMed Central

    Anderson, Jeri L.; Apostoaei, A. Iulian; Thomas, Brian A.

    2015-01-01

    The National Institute for Occupational Safety and Health (NIOSH) is currently studying mortality in a cohort of 6409 workers at a former uranium processing facility. As part of this study, over 220 000 urine samples were used to reconstruct organ doses due to internal exposure to uranium. Most of the available computational programs designed for analysis of bioassay data handle a single case at a time, and thus require a significant outlay of time and resources for the exposure assessment of a large cohort. NIOSH is currently supporting the development of a computer program, InDEP (Internal Dose Evaluation Program), to facilitate internal radiation exposure assessment as part of epidemiological studies of both uranium- and plutonium-exposed cohorts. A novel feature of InDEP is its batch processing capability which allows for the evaluation of multiple study subjects simultaneously. InDEP analyses bioassay data and derives intakes and organ doses with uncertainty estimates using least-squares regression techniques or using the Bayes’ Theorem as applied to internal dosimetry (Bayesian method). This paper describes the application of the current version of InDEP to formulate assumptions about the characteristics of exposure at the study facility that were used in a detailed retrospective intake and organ dose assessment of the cohort. PMID:22683620

  4. Ecological and toxicological responses in a multistressor scenario: Are monitoring programs showing the stressors or just showing stress? A case study in Brazil.

    PubMed

    López-Doval, Julio C; Meirelles, Sergio Tadeu; Cardoso-Silva, Sheila; Moschini-Carlos, Viviane; Pompêo, Marcelo

    2016-01-01

    The Metropolitan Region of São Paulo (MRSP) is located in the Brazilian State of São Paulo and reservoirs in this region are vital for water supply and energy production. Changes in economic, social, and demographic trends produced pollution of water bodies, decreasing water quality for human uses and affecting freshwater populations. The presence of emerging pollutants, classical priority substances, nutrient excess and the interaction with tropical-climate conditions require periodic reviews of water policies and monitoring programs in order to detect and manage these threats in a global change scenario. The objective of this work is to determine whether the monitoring program of the São Paulo's Environmental Agency, is sufficient to explain the toxicological and biological responses observed in organisms in reservoirs of the MRSP, and whether it can identify the possible agents causing these responses. For that, we used publicly available data on water quality compiled by this agency in their routine monitoring program. A general overview of these data and a chemometric approach to analyze the responses of biotic indexes and toxicological bioassays, as a function of the physical and chemical parameters monitored, were performed. Data compiled showed temporal and geographical information gaps on variables measured. Toxicological responses have been observed in the reservoirs of the MRSP, together with a high incidence of impairments of the zooplankton community. This demonstrates the presence of stressors that affect the viability of organisms and populations. The statistical approach showed that the data compiled by the environmental agency are insufficient to identify and explain the factors causing the observed ecotoxicological responses and impairments in the zooplankton community, and are therefore insufficient to identify clear cause-effect relationships. Stressors different from those analyzed could be responsible for the observed responses. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Responses of lone star tick (acari: ixodidae) nymphs to the repellent deet applied in acetone and ethanol solutions in vitro bioassays

    USDA-ARS?s Scientific Manuscript database

    Behavioral bioassays remain a standard tool in the discovery, development, and registration of repellents. Although tick repellent bioassays tend to be rather uncomplicated, several factors can influence their outcomes. Typically repellent bioassays use a solvent, such as acetone or ethanol, to disp...

  6. Programmer's manual for MMLE3, a general FORTRAN program for maximum likelihood parameter estimation

    NASA Technical Reports Server (NTRS)

    Maine, R. E.

    1981-01-01

    The MMLE3 is a maximum likelihood parameter estimation program capable of handling general bilinear dynamic equations of arbitrary order with measurement noise and/or state noise (process noise). The basic MMLE3 program is quite general and, therefore, applicable to a wide variety of problems. The basic program can interact with a set of user written problem specific routines to simplify the use of the program on specific systems. A set of user routines for the aircraft stability and control derivative estimation problem is provided with the program. The implementation of the program on specific computer systems is discussed. The structure of the program is diagrammed, and the function and operation of individual routines is described. Complete listings and reference maps of the routines are included on microfiche as a supplement. Four test cases are discussed; listings of the input cards and program output for the test cases are included on microfiche as a supplement.

  7. A yeast bioassay for direct measurement of thyroid hormone disrupting effects in water without sample extraction, concentration, or sterilization.

    PubMed

    Li, Jian; Ren, Shujuan; Han, Shaolun; Li, Na

    2014-04-01

    The present study introduces an improved yeast bioassay for rapid yet sensitive evaluation of thyroid hormone disruption at the level of thyroid receptor (TR) in environmental water samples. This assay does not require water sample preparation and thus requires very little hands-on time. Based on different β-galactosidase substrates, two modified bioassays, a colorimetric bioassay and a chemiluminescent bioassay, were developed. The compounds tested included the known thyroid hormone 3,3',5-triiodo-l-thyronine (T3), the specific TR antagonist amiodarone hydrochloride (AH) and phthalate esters (PAEs), which potentially disrupt thyroid hormone signaling. The EC50 values for T3 were similar to those previously obtained using a 96-well plate bioassay. TR antagonism by AH was studied in the presence of 2.5 × 10(-7)M T3, and the concentration producing 20% of the maximum effect (RIC20) for AH was 3.1 × 10(-7)M and 7.8 × 10(-9)M for the colorimetric bioassay and chemiluminescent bioassay, respectively. None of the tested PAEs induced β-galactosidase expression, but diethylhexyl phthalate, benzyl butyl phthalate and dibutyl phthalate demonstrated TR antagonism. Furthermore, water samples collected from Guanting reservoir in Beijing were evaluated. Although TR agonism was not observed, antagonism was detected in all water samples and is expressed as AH equivalents. The toxicology equivalent quantity values obtained by the chemiluminescent bioassay ranged from 21.2 ± 1.6 to 313.9 ± 28.8 μg L(-1) AH, and similar values were obtained for the colorimetric bioassay. The present study shows that the modified yeast bioassay can be used as a valuable tool for quantification of thyroid hormone disrupting effects in environmental water samples. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. 32 CFR Appendix C to Part 310 - DoD Blanket Routine Uses

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false DoD Blanket Routine Uses C Appendix C to Part...) PRIVACY PROGRAM DOD PRIVACY PROGRAM Pt. 310, App. C Appendix C to Part 310—DoD Blanket Routine Uses (See paragraph (c) of § 310.22 of subpart E) A. Routine Use—Law Enforcement If a system of records maintained by...

  9. Potential for Development of an Escherichia coli—Based Biosensor for Assessing Bioavailable Methionine: A Review

    PubMed Central

    Chalova, Vesela I.; Froelich, Clifford A.; Ricke, Steven C.

    2010-01-01

    Methionine is an essential amino acid for animals and is typically considered one of the first limiting amino acids in animal feed formulations. Methionine deficiency or excess in animal diets can lead to sub-optimal animal performance and increased environmental pollution, which necessitates its accurate quantification and proper dosage in animal rations. Animal bioassays are the current industry standard to quantify methionine bioavailability. However, animal-based assays are not only time consuming, but expensive and are becoming more scrutinized by governmental regulations. In addition, a variety of artifacts can hinder the variability and time efficacy of these assays. Microbiological assays, which are based on a microbial response to external supplementation of a particular nutrient such as methionine, appear to be attractive potential alternatives to the already established standards. They are rapid and inexpensive in vitro assays which are characterized with relatively accurate and consistent estimation of digestible methionine in feeds and feed ingredients. The current review discusses the potential to develop Escherichia coli-based microbial biosensors for methionine bioavailability quantification. Methionine biosynthesis and regulation pathways are overviewed in relation to genetic manipulation required for the generation of a respective methionine auxotroph that could be practical for a routine bioassay. A prospective utilization of Escherichia coli methionine biosensor would allow for inexpensive and rapid methionine quantification and ultimately enable timely assessment of nutritional profiles of feedstuffs. PMID:22319312

  10. Toxic C17-Sphinganine Analogue Mycotoxin, Contaminating Tunisian Mussels, Causes Flaccid Paralysis in Rodents

    PubMed Central

    Marrouchi, Riadh; Benoit, Evelyne; Le Caer, Jean-Pierre; Belayouni, Nawel; Belghith, Hafedh; Molgó, Jordi; Kharrat, Riadh

    2013-01-01

    Severe toxicity was detected in mussels from Bizerte Lagoon (Northern Tunisia) using routine mouse bioassays for detecting diarrheic and paralytic toxins not associated to classical phytoplankton blooming. The atypical toxicity was characterized by rapid mouse death. The aim of the present work was to understand the basis of such toxicity. Bioassay-guided chromatographic separation and mass spectrometry were used to detect and characterize the fraction responsible for mussels’ toxicity. Only a C17-sphinganine analog mycotoxin (C17-SAMT), with a molecular mass of 287.289 Da, was found in contaminated shellfish. The doses of C17-SAMT that were lethal to 50% of mice were 750 and 150 μg/kg following intraperitoneal and intracerebroventricular injections, respectively, and 900 μg/kg following oral administration. The macroscopic general aspect of cultures and the morphological characteristics of the strains isolated from mussels revealed that the toxicity episodes were associated to the presence of marine microfungi (Fusarium sp., Aspergillus sp. and Trichoderma sp.) in contaminated samples. The major in vivo effect of C17-SAMT on the mouse neuromuscular system was a dose- and time-dependent decrease of compound muscle action potential amplitude and an increased excitability threshold. In vitro, C17-SAMT caused a dose- and time-dependent block of directly- and indirectly-elicited isometric contraction of isolated mouse hemidiaphragms. PMID:24287956

  11. Effects of the Practiced Routines Parent Training Program on Behavioral Strategy Use, Parental Well-Being, and Child Challenging Behavior in Parents of Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Raulston, Tracy Jane

    2017-01-01

    In this study, a concurrent randomized multiple baseline across three parent-child dyads single-case design was employed to evaluate the effects of a brief three-week parent training program, titled Practiced Routines. The Practiced Routines parent training program included positive behavior supports (PBS) and mindfulness strategies within the…

  12. Comparison of laboratory and field bioassays of lab-reared Cydia pomonella (Lepidoptera: Tortricidae) quality and field performance.

    USDA-ARS?s Scientific Manuscript database

    Maximum production and fitness of insect species that are mass-reared for biological control programs such as the sterile insect technique (SIT) have benefitted from the employment of quality control and quality management. With a growing interest in the use of SIT as a tactic for the suppression/e...

  13. Using ToxCast in vitro Assays in the Hierarchical Quantitative Structure-Activity Relationship (QSAR) Modeling for Predicting in vivo Toxicity of Chemicals

    EPA Science Inventory

    The goal of chemical toxicology research is utilizing short term bioassays and/or robust computational methods to predict in vivo toxicity endpoints for chemicals. The ToxCast program established at the US Environmental Protection Agency (EPA) is addressing this goal by using ca....

  14. Cellular fatty acid analysis as a potential tool for predicting mosquitocidal activity of Bacillus sphaericus strains.

    PubMed Central

    Frachon, E; Hamon, S; Nicolas, L; de Barjac, H

    1991-01-01

    Gas-liquid chromatography of fatty acid methyl esters and numerical analysis were carried out with 114 Bacillus sphaericus strains. Since only two clusters harbored mosquitocidal strains, this technique could be developed in screening programs to limit bioassays on mosquito larvae. It also allows differentiation of highly homologous strains. PMID:1781697

  15. CALCMIN - an EXCEL™ Visual Basic application for calculating mineral structural formulae from electron microprobe analyses

    NASA Astrophysics Data System (ADS)

    Brandelik, Andreas

    2009-07-01

    CALCMIN, an open source Visual Basic program, was implemented in EXCEL™. The program was primarily developed to support geoscientists in their routine task of calculating structural formulae of minerals on the basis of chemical analysis mainly obtained by electron microprobe (EMP) techniques. Calculation programs for various minerals are already included in the form of sub-routines. These routines are arranged in separate modules containing a minimum of code. The architecture of CALCMIN allows the user to easily develop new calculation routines or modify existing routines with little knowledge of programming techniques. By means of a simple mouse-click, the program automatically generates a rudimentary framework of code using the object model of the Visual Basic Editor (VBE). Within this framework simple commands and functions, which are provided by the program, can be used, for example, to perform various normalization procedures or to output the results of the computations. For the clarity of the code, element symbols are used as variables initialized by the program automatically. CALCMIN does not set any boundaries in complexity of the code used, resulting in a wide range of possible applications. Thus, matrix and optimization methods can be included, for instance, to determine end member contents for subsequent thermodynamic calculations. Diverse input procedures are provided, such as the automated read-in of output files created by the EMP. Furthermore, a subsequent filter routine enables the user to extract specific analyses in order to use them for a corresponding calculation routine. An event-driven, interactive operating mode was selected for easy application of the program. CALCMIN leads the user from the beginning to the end of the calculation process.

  16. Crew/computer communications study. Volume 2: Appendixes

    NASA Technical Reports Server (NTRS)

    Johannes, J. D.

    1974-01-01

    The software routines developed during the crew/computer communications study are described to provide the user with an understanding of each routine, any restrictions in use, the required input data, and expected results after executing the routines. The combination of routines to generate a crew/computer communications application is also explained. The programmable keyboard and display used by the program is described, and an experiment scenario is provided to illustrate the relationship between the program frames when they are grouped into activity phases. Program descriptions and a user's guide are also presented. For Vol. 1, see N74-18843.

  17. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In: United...

  18. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In: United...

  19. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In: United...

  20. Using lone star ticks, Amblyomma americanum (Acari: Ixodidae) in in vitro laboratory bioassays of repellents: dimensions, duration, and variability

    USDA-ARS?s Scientific Manuscript database

    The in vitro bioassay is an important tool in repellent discovery and development, with a variety of bioassays used in recent years. Several factors, such as the dimensions and configuration of test surfaces and duration of tick exposure, can influence the outcome of bioassays. We tested two tick re...

  1. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown... publications: (a) Bigland, C. H. and A. J. DaMassa, “A Bio-Assay for Mycoplasma Gallisepticum.” In: United...

  2. Determination of paralytic shellfish toxins in shellfish by receptor binding assay: collaborative study.

    PubMed

    Van Dolah, Frances M; Fire, Spencer E; Leighfield, Tod A; Mikulski, Christina M; Doucette, Gregory J

    2012-01-01

    A collaborative study was conducted on a microplate format receptor binding assay (RBA) for paralytic e shellfish toxins (PST). The assay quantifies the composite PST toxicity in shellfish samples based on the ability of sample extracts to compete with (3)H saxitoxin (STX) diHCl for binding to voltage-gated sodium channels in a rat brain membrane preparation. Quantification of binding can be carried out using either a microplate or traditional scintillation counter; both end points were included in this study. Nine laboratories from six countries completed the study. One laboratory analyzed the samples using the precolumn oxidation HPLC method (AOAC Method 2005.06) to determine the STX congener composition. Three laboratories performed the mouse bioassay (AOAC Method 959.08). The study focused on the ability of the assay to measure the PST toxicity of samples below, near, or slightly above the regulatory limit of 800 (microg STX diHCl equiv./kg). A total of 21 shellfish homogenates were extracted in 0.1 M HCl, and the extracts were analyzed by RBA in three assays on separate days. Samples included naturally contaminated shellfish samples of different species collected from several geographic regions, which contained varying STX congener profiles due to their exposure to different PST-producing dinoflagellate species or differences in toxin metabolism: blue mussel (Mytilus edulis) from the U.S. east and west coasts, California mussel (Mytilus californianus) from the U.S. west coast, chorito mussel (Mytilus chiliensis) from Chile, green mussel (Perna canaliculus) from New Zealand, Atlantic surf clam (Spisula solidissima) from the U.S. east coast, butter clam (Saxidomus gigantea) from the west coast of the United States, almeja clam (Venus antiqua) from Chile, and Atlantic sea scallop (Plactopecten magellanicus) from the U.S. east coast. All samples were provided as whole animal homogenates, except Atlantic sea scallop and green mussel, from which only the hepatopancreas was homogenized. Among the naturally contaminated samples, five were blind duplicates used for calculation of RSDr. The interlaboratory RSDR of the assay for 21 samples tested in nine laboratories was 33.1%, yielding a HorRat value of 2.0. Removal of results for one laboratory that reported systematically low values resulted in an average RSDR of 28.7% and average HorRat value of 1.8. Intralaboratory RSDr based on five blind duplicate samples tested in separate assays, was 25.1%. RSDr obtained by individual laboratories ranged from 11.8 to 34.9%. Laboratories that are routine users of the assay performed better than nonroutine users, with an average RSDr of 17.1%. Recovery of STX from spiked shellfish homogenates was 88.1-93.3%. Correlation with the mouse bioassay yielded a slope of 1.64 and correlation coefficient (r(2)) of 0.84, while correlation with the precolumn oxidation HPLC method yielded a slope of 1.20 and an r(2) of 0.92. When samples were sorted according to increasing toxin concentration (microg STX diHCl equiv./kg) as assessed by the mouse bioassay, the RBA returned no false negatives relative to the 800 microg STX diHCl equiv./kg regulatory limit for shellfish. Currently, no validated methods other than the mouse bioassay directly measure a composite toxic potency for PST in shellfish. The results of this interlaboratory study demonstrate that the RBA is suitable for the routine determination of PST in shellfish in appropriately equipped laboratories.

  3. The fifth plot of the Carcinogenic Potency Database: results of animal bioassays published in the general literature through 1988 and by the National Toxicology Program through 1989.

    PubMed Central

    Gold, L S; Manley, N B; Slone, T H; Garfinkel, G B; Rohrbach, L; Ames, B N

    1993-01-01

    This paper is the fifth plot of the Carcinogenic Potency Database (CPDB) that first appeared in this journal in 1984 (1-5). We report here results of carcinogenesis bioassays published in the general literature between January 1987 and December 1988, and in technical reports of the National Toxicology Program between July 1987 and December 1989. This supplement includes results of 412 long-term, chronic experiments of 147 test compounds and reports the same information about each experiment in the same plot format as the earlier papers: the species and strain of test animal, the route and duration of compound administration, dose level and other aspects of experimental protocol, histopathology and tumor incidence, TD50 (carcinogenic potency) and its statistical significance, dose response, author's opinion about carcinogenicity, and literature citation. We refer the reader to the 1984 publications (1,5,6) for a guide to the plot of the database, a complete description of the numerical index of carcinogenic potency, and a discussion of the sources of data, the rationale for the inclusion of particular experiments and particular target sites, and the conventions adopted in summarizing the literature. The five plots of the database are to be used together, as results of individual experiments that were published earlier are not repeated. In all, the five plots include results of 4487 experiments on 1136 chemicals. Several analyses based on the CPDB that were published earlier are described briefly, and updated results based on all five plots are given for the following earlier analyses: the most potent TD50 value by species, reproducibility of bioassay results, positivity rates, and prediction between species.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8354183

  4. Potential biological targets for bioassay development in drug discovery of Sturge-Weber syndrome.

    PubMed

    Mohammadipanah, Fatemeh; Salimi, Fatemeh

    2017-04-29

    Sturge-Weber Syndrome (SWS) is among the neurocutaneous diseases, which has several clinical manifestations of ocular (glaucoma), cutaneous (port-wine stain), neurological (seizures) and vascular problems. Molecular mechanisms of SWS pathogenesis are initiated by the somatic mutation in GNAQ. Therefore, no definite treatments exist for the SWS and treatment options only mitigate the intensity of its clinical manifestations. Biological assay design for drug discovery against this syndrome demands comprehensive knowledge on mechanisms which are involved in its pathogenesis. By analysis of the interrelated molecular targets of SWS, some in vitro bioassay systems can be allotted for drug screening against this syndrome. Development of such platforms of bioassay can bring along the implementation of high throughput screening of natural or synthetic compounds in drug discovery programs. Regarding the fact that study of biological targets and their integration in biological assay design can facilitate the process of effective drug discovery; some potential biological targets and their respective biological assay for SWS drug discovery are propounded in this review. For this purpose, some biological targets for SWS drug discovery such as acetylcholine esterase, alkaline phosphatase, gamma-aminobutyricacidergic, Hypoxia-Inducible Factor (HIF) -1α and 2α are suggested. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Design and operation of internal dosimetry programs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaBone, T.R.

    1991-01-01

    The proposed revision to USNRC 10 CFR 20 and the USDOE Order 5480.11 require intakes of radioactive material to be evaluated. Radiation dose limits are based on the sum of effective dose equivalent from intakes and the whole body dose from external sources. These significant changes in the regulations will require, at a minimum, a complete review of personnel monitoring programs to determine their adequacy. In this session we will review a systematic method of designing a routine personnel monitoring program that will comply with the requirements of the new regulations. Specific questions discussed are: (a) What are the goalsmore » and objectives of a routine personnel monitoring program (b) When is a routine personnel monitoring program required (c) What are the required capabilities of the routine personnel monitoring program (d) What should be done with the information generated in a personnel monitoring program Specific recommendations and interpretations are given in the session. 5 refs., 3 figs., 33 tabs.« less

  6. Repellent activities of dichloromethane extract of Allium sativum (garlic) (Liliaceae) against Hyalomma rufipes (Acari).

    PubMed

    Nchu, Felix; Magano, Solomon R; Eloff, Jacobus N

    2016-12-02

    Dichloromethane (DCM) extract of garlic (Allium sativum Linn.) bulbs was assessed for its repellent effect against the hard tick, Hyalomma rufipes (Acari: Ixodidae) using two tick behavioural bioassays; Type A and Type B repellency bioassays, under laboratory conditions. These bioassays exploit the questing behaviour of H. rufipes, a tick that in nature displays ambush strategy, seeking its host by climbing up on vegetation and attaching to a passing host. One hundred microlitres (100 µL) of the test solution containing DCM extract of garlic bulbs and DCM at concentrations of 0.35%, 0.7% or 1.4% w/v were evaluated. DCM only was used for control. Tick repellency increased significantly (R2 = 0.98) with increasing concentration (40.03% - 86.96%) yielding an EC50 of 0.45% w/v in Type B repellency bioassay. At concentration of 1.4% w/v, the DCM extract of garlic bulbs produced high repellency index of 87% (male ticks) and 87.5% (female ticks) in the Type A repellency bioassay. Only 4% avoidance of male ticks or female ticks was recorded in the Type B repellency bioassay. In the corresponding controls, the mean numbers of non-repelled male or female ticks were 80% and 41 males or 38 females of 50 ticks in the Type A and Type B repellency bioassays, respectively. The variations in the results could be attributed to the difference in tick repellent behaviours that were assessed by the two repellency bioassays; the Type A repellency bioassay assessed repellent effect of garlic extracts without discriminating between deterrence and avoidance whereas the Type B repellency bioassay only assessed avoidance response. Generally, DCM extract of garlic was repellent against H. rufipes, albeit weak tick repellency was obtained in the Type B repellency bioassay. Furthermore, this study established that the tick repellent activity of garlic extracts is predominantly by deterrence.

  7. Computer routine adds plotting capabilities to existing programs

    NASA Technical Reports Server (NTRS)

    Harris, J. C.; Linnekin, J. S.

    1966-01-01

    PLOTAN, a generalized plot analysis routine written for the IBM 7094 computer, minimizes the difficulties in adding plot capabilities to large existing programs. PLOTAN is used in conjunction with a binary tape writing routine and has the ability to plot any variable on the intermediate binary tape as a function of any other.

  8. The NIEHS Predictive-Toxicology Evaluation Project.

    PubMed Central

    Bristol, D W; Wachsman, J T; Greenwell, A

    1996-01-01

    The Predictive-Toxicology Evaluation (PTE) project conducts collaborative experiments that subject the performance of predictive-toxicology (PT) methods to rigorous, objective evaluation in a uniquely informative manner. Sponsored by the National Institute of Environmental Health Sciences, it takes advantage of the ongoing testing conducted by the U.S. National Toxicology Program (NTP) to estimate the true error of models that have been applied to make prospective predictions on previously untested, noncongeneric-chemical substances. The PTE project first identifies a group of standardized NTP chemical bioassays either scheduled to be conducted or are ongoing, but not yet complete. The project then announces and advertises the evaluation experiment, disseminates information about the chemical bioassays, and encourages researchers from a wide variety of disciplines to publish their predictions in peer-reviewed journals, using whatever approaches and methods they feel are best. A collection of such papers is published in this Environmental Health Perspectives Supplement, providing readers the opportunity to compare and contrast PT approaches and models, within the context of their prospective application to an actual-use situation. This introduction to this collection of papers on predictive toxicology summarizes the predictions made and the final results obtained for the 44 chemical carcinogenesis bioassays of the first PTE experiment (PTE-1) and presents information that identifies the 30 chemical carcinogenesis bioassays of PTE-2, along with a table of prediction sets that have been published to date. It also provides background about the origin and goals of the PTE project, outlines the special challenge associated with estimating the true error of models that aspire to predict open-system behavior, and summarizes what has been learned to date. PMID:8933048

  9. Profiling Animal Toxicants by Automatically Mining Public Bioassay Data: A Big Data Approach for Computational Toxicology

    PubMed Central

    Zhang, Jun; Hsieh, Jui-Hua; Zhu, Hao

    2014-01-01

    In vitro bioassays have been developed and are currently being evaluated as potential alternatives to traditional animal toxicity models. Already, the progress of high throughput screening techniques has resulted in an enormous amount of publicly available bioassay data having been generated for a large collection of compounds. When a compound is tested using a collection of various bioassays, all the testing results can be considered as providing a unique bio-profile for this compound, which records the responses induced when the compound interacts with different cellular systems or biological targets. Profiling compounds of environmental or pharmaceutical interest using useful toxicity bioassay data is a promising method to study complex animal toxicity. In this study, we developed an automatic virtual profiling tool to evaluate potential animal toxicants. First, we automatically acquired all PubChem bioassay data for a set of 4,841 compounds with publicly available rat acute toxicity results. Next, we developed a scoring system to evaluate the relevance between these extracted bioassays and animal acute toxicity. Finally, the top ranked bioassays were selected to profile the compounds of interest. The resulting response profiles proved to be useful to prioritize untested compounds for their animal toxicity potentials and form a potential in vitro toxicity testing panel. The protocol developed in this study could be combined with structure-activity approaches and used to explore additional publicly available bioassay datasets for modeling a broader range of animal toxicities. PMID:24950175

  10. Profiling animal toxicants by automatically mining public bioassay data: a big data approach for computational toxicology.

    PubMed

    Zhang, Jun; Hsieh, Jui-Hua; Zhu, Hao

    2014-01-01

    In vitro bioassays have been developed and are currently being evaluated as potential alternatives to traditional animal toxicity models. Already, the progress of high throughput screening techniques has resulted in an enormous amount of publicly available bioassay data having been generated for a large collection of compounds. When a compound is tested using a collection of various bioassays, all the testing results can be considered as providing a unique bio-profile for this compound, which records the responses induced when the compound interacts with different cellular systems or biological targets. Profiling compounds of environmental or pharmaceutical interest using useful toxicity bioassay data is a promising method to study complex animal toxicity. In this study, we developed an automatic virtual profiling tool to evaluate potential animal toxicants. First, we automatically acquired all PubChem bioassay data for a set of 4,841 compounds with publicly available rat acute toxicity results. Next, we developed a scoring system to evaluate the relevance between these extracted bioassays and animal acute toxicity. Finally, the top ranked bioassays were selected to profile the compounds of interest. The resulting response profiles proved to be useful to prioritize untested compounds for their animal toxicity potentials and form a potential in vitro toxicity testing panel. The protocol developed in this study could be combined with structure-activity approaches and used to explore additional publicly available bioassay datasets for modeling a broader range of animal toxicities.

  11. A fluorescence-based bioassay for aquatic macrophytes and its suitability for effect analysis of non-photosystem II inhibitors.

    PubMed

    Küster, Anette; Pohl, Korinna; Altenburger, Rolf

    2007-09-01

    BACKGROUND, GOALS AND SCOPE: During the last years the miniaturization of toxicity test systems for rapid and parallel measurements of large quantities of samples has often been discussed. For unicellular algae as well as for aquatic macrophytes, fluorescence-based miniaturized test systems have been introduced to analyze photosystem II (PSII) inhibitors. Nevertheless, high-throughput screening should also guarantee the effect detection of a broad range of toxicants in order to ensure routinely applicable, high-throughput measuring device experiments which can cover a broad range of toxicants and modes of action others than PSII inhibition. Thus, the aim of this study was to establish a fast and reproducible measuring system for non-PSII inhibitors for aquatic macrophyte species to overcome major limitations for use. A newly developed imaging pulse-amplitude-modulated chlorophyll fluorometer (I-PAM) was applied as an effect detector in short-term bioassays with the aquatic macrophyte species Lemna minor. This multiwell-plate based measuring device enabled the incubation and measurement of up to 24 samples in parallel. The chemicals paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII herbicides, polycyclic aromatic hydrocarbons (PAHs) and pharmaceuticals and personal care products (PPCPs), which are often detected in the aquatic environment. The I-PAM was used (i) to establish and validate the sensitivity of the test system to the three non-PSII inhibitors, (ii) to compare the test systems with standardized and established biotests for aquatic macrophytes, and (iii) to define necessary time scales in aquatic macrophyte testing. For validation of the fluorescence-based assay, the standard growth test with L. minor (ISO/DIS 20079) was performed in parallel for each chemical. The results revealed that fluorescence-based measurements with the I-PAM allow rapid and parallel analysis of large amounts of aquatic macrophyte samples. The I-PAM enabled the recording of concentration-effect-curves with L. minor samples on a 24-well plate with single measurements. Fluorescence-based concentration-effect-curves could be detected for all three chemicals after only 1 h of incubation. After 4-5 h incubation time, the maximum inhibition of fluorescence showed an 80-100% effect for the chemicals tested. The EC50 after 24 h incubation were estimated to be 0.06 mg/L, 0.84 mg/L and 1.69 mg/L for paraquat-dichloride, alizarine and triclosan, respectively. The results obtained with the I-PAM after 24 h for the herbicide paraquat-dichloride and the polycyclic aromatic hydrocarbon alizarine were in good accordance with median effective concentrations (EC50s) obtained by the standardized growth test for L. minor after 7 d incubation (0.09 mg/L and 0.79 mg/L for paraquat-dichloride and alizarine, respectively). Those results were in accordance with literature findings for the two chemicals. In contrast, fluorescence-based EC50 of the antimicrobial agent triclosan proved to be two orders of magnitude greater when compared to the standard growth test with 7 d incubation time (0.026 mg/L) as well as with literature findings. Typically, aquatic macrophyte testing is very time consuming and relies on laborious experimental set-ups. The I-PAM measuring device enabled fast effect screening for the three chemicals tested. While established test systems for aquatic macrophytes need incubation times of > or = 7 d, the I-PAM can detect inhibitory effects much earlier (24 h), even if inhibition of chemicals is not specifically associated with PSII. Thus, the fluorescence-based bioassay with the I-PAM offers a promising approach for the miniaturization and high-throughput testing of chemicals with aquatic macrophytes. For the chemical triclosan, however, the short-term effect prediction with the I-PAM has been shown to be less sensitive than with long-term bioassays, which might be due to physicochemical substance properties such as lipophilicity. The results of this study show that the I-PAM represents a promising tool for decreasing the incubation times of aquatic macrophyte toxicity testing to about 24 h as a supplement to existing test batteries. The applicability of this I-PAM bioassay on emergent and submerged aquatic macrophyte species should be investigated in further studies. Regarding considerations that physicochemical properties of the tested substances might play an important role in microplate bioassays, the I-PAM bioassay should either be accompanied by evaluating physicochemical properties modeled from structural information prior to an experimental investigation, or by intensified chemical analyses to identify and determine nominal concentrations of the toxicants tested. The chemicals paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII herbicides, PAHs and PPCPs which are often detected in the aquatic environment. Nevertheless, in order to ensure a routinely applicable measuring device, experiments with a broader range of toxicants and samples of surface and/or waste waters are necessary.

  12. Bioassay-guided investigation of two monarda essential oils as repellents of yellow fever mosquito Aedes aegypti

    USDA-ARS?s Scientific Manuscript database

    As part of an ongoing research program to identify active mosquito repellents, Monarda bradburiana Beck and M. fistulosa L. essential oils showed potent repellents with minimum effective dosages (MED) of 0.055 ± 0.036 and 0.078 ± 0.027 mg/cm2, respectively, compared to reference standard N,N-diethyl...

  13. Problems with detection of intakes of very insoluble plutonium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bihl, D.E.; Lynch, T.P.; Carbaugh, E.H.

    1988-08-01

    Several human cases involving inhalation of plutonium oxide at Hanford have shown clearance half-times from the lung that are much longer than those recommended for class Y material in Publication 30 of the International Commission on Radiological Protection (ICRP 1979). Because the material is much more tenaciously retained in the lung than ''normal'' class Y material, the Hanford Internal Dosimetry Program has been referring to it as ''super'' class Y. This material poses some major challenges with regard to the design and operation of bioassay monitoring programs. Because of the relative completeness of their data, 10 cases that show lungmore » retention half-times in excess of 5000 days are of particular interest. However, the bioassay data for these cases span the past 30 years and involve various sampling methods and detection limits in vogue at the time. Furthermore, the data were collected for the purpose of determining compliance with regulations in place at the time, rather than for research or modeling of clearance pathways and rates. So from a modeling perspective, the data have gaps, but are sufficiently complete to be convincing. 3 refs., 2 figs., 2 tabs.« less

  14. Development of a bioanalytical test battery for water quality monitoring: Fingerprinting identified micropollutants and their contribution to effects in surface water.

    PubMed

    Neale, Peta A; Altenburger, Rolf; Aït-Aïssa, Selim; Brion, François; Busch, Wibke; de Aragão Umbuzeiro, Gisela; Denison, Michael S; Du Pasquier, David; Hilscherová, Klára; Hollert, Henner; Morales, Daniel A; Novák, Jiří; Schlichting, Rita; Seiler, Thomas-Benjamin; Serra, Helene; Shao, Ying; Tindall, Andrew J; Tollefsen, Knut Erik; Williams, Timothy D; Escher, Beate I

    2017-10-15

    Surface waters can contain a diverse range of organic pollutants, including pesticides, pharmaceuticals and industrial compounds. While bioassays have been used for water quality monitoring, there is limited knowledge regarding the effects of individual micropollutants and their relationship to the overall mixture effect in water samples. In this study, a battery of in vitro bioassays based on human and fish cell lines and whole organism assays using bacteria, algae, daphnids and fish embryos was assembled for use in water quality monitoring. The selection of bioassays was guided by the principles of adverse outcome pathways in order to cover relevant steps in toxicity pathways known to be triggered by environmental water samples. The effects of 34 water pollutants, which were selected based on hazard quotients, available environmental quality standards and mode of action information, were fingerprinted in the bioassay test battery. There was a relatively good agreement between the experimental results and available literature effect data. The majority of the chemicals were active in the assays indicative of apical effects, while fewer chemicals had a response in the specific reporter gene assays, but these effects were typically triggered at lower concentrations. The single chemical effect data were used to improve published mixture toxicity modeling of water samples from the Danube River. While there was a slight increase in the fraction of the bioanalytical equivalents explained for the Danube River samples, for some endpoints less than 1% of the observed effect could be explained by the studied chemicals. The new mixture models essentially confirmed previous findings from many studies monitoring water quality using both chemical analysis and bioanalytical tools. In short, our results indicate that many more chemicals contribute to the biological effect than those that are typically quantified by chemical monitoring programs or those regulated by environmental quality standards. This study not only demonstrates the utility of fingerprinting single chemicals for an improved understanding of the biological effect of pollutants, but also highlights the need to apply bioassays for water quality monitoring in order to prevent underestimation of the overall biological effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Evaluation of the mutagenicity and carcinogenicity of motor vehicle emissions in short-term bioassays.

    PubMed Central

    Lewtas, J

    1983-01-01

    Incomplete combustion of fuel in motor vehicles results in the emission of submicron carbonaceous particles which, after cooling and dilution, contain varying quantities of extractable organic constituents. These organics are mutagenic in bacteria. Confirmatory bioassays in mammalian cells provide the capability of detecting chromosomal and DNA damage in addition to gene mutations. In order to evaluate the mutagenicity of these organics in mammalian cells, extractable organics from particle emissions from several diesel and gasoline vehicles were compared in a battery of microbial, mammalian cell and in vivo bioassays. The mammalian cell mutagenicity bioassays were selected to detect gene mutations, DNA damage, and chromosomal effects. Carcinogenesis bioassays conducted included short-term assays for oncogenic transformation and skin tumorigenesis. The results in different assay systems are compared both qualitatively and quantitatively. Good quantitative correlations were observed between several mutagenesis and carcinogenesis bioassays for this series of diesel and gasoline emissions. PMID:6186475

  16. The H4IIE cell bioassay as an indicator of dioxin-like chemicals in wildlife and the environment

    USGS Publications Warehouse

    White, J.J.; Schmitt, C.J.; Tillitt, D. E.

    2004-01-01

    The H4IIE cell bioassay has proven utility as a screening tool for planar halogenated hydrocarbons (PHHs) and structurally similar chemicals accumulated in organisms from the wild. This bioassay has additional applications in hazard assessment of PHH exposed populations. In this review, the toxicological principles, current protocols, performance criteria, and field applications for the assay are described. The H4IIE cell bioassay has several advantages over the analytical measurement of PHHs in environmental samples, but conclusions from studies can be strengthened when both bioassay and analytical chemistry data are presented together. Often, the bioassay results concur with biological effects in organisms and support direct measures of PHHs. For biomonitoring purposes and prioritization of PHH-contaminated environments, the H4IIE bioassay may be faster and less expensive than analytical measurements. The H4IIE cell bioassay can be used in combination with other biomarkers such as in vivo measurements of CYP1A1 induction to help pinpoint the sources and identities of dioxin-like chemicals. The number of studies that measure H4IIE-derived TCDD-EQs continues to increase, resulting in subtle improvements over time. Further experiments are required to determine if TCDD-EQs derived from mammalian cells are adequate predictors of toxicity to non-mammalian species. The H4IIE cell bioassay has been used in over 300 published studies, and its combination of speed, simplicity, and ability to integrate the effects of complex containment mixtures makes it a valuable addition to hazard assessment and biomonitoring studies.

  17. Deltamethrin resistance in the sea louse Caligus rogercresseyi (Boxhall and Bravo) in Chile: bioassay results and usage data for antiparasitic agents with references to Norwegian conditions.

    PubMed

    Helgesen, K O; Bravo, S; Sevatdal, S; Mendoza, J; Horsberg, T E

    2014-10-01

    The sea louse Caligus rogercresseyi is a major threat to Chilean salmonid farming. Pyrethroids have been used for anticaligus treatments since 2007, but have shown reduced effect, most likely due to resistance development. Pyrethroid resistance is also a known problem in Lepeophtheirus salmonis in the Northern Hemisphere. This study describes the development of deltamethrin resistance in C. rogercresseyi based on bioassays and usage data for pyrethroids in Chilean aquaculture. These results were compared to bioassays from L. salmonis from Norway and to Norwegian usage data. Available deltamethrin bioassay results from 2007 and 2008, as well as bioassays from Norway, were collected and remodelled. Bioassays were performed on field-collected sea lice in region X in Chile in 2012 and 2013. Bioassays from 2007 were performed prior to the introduction of pyrethroids to the Chilean market. Both the results from 2008 and 2012 showed an increased resistance. Increased pyrethroid resistance was also indicated by the increased use of pyrethroids in Chilean aquaculture compared with the production of salmonids. A similar trend was seen in the Norwegian usage data. The bioassay results from Chile from 2012 and 2013 also indicated a difference in the susceptibility to deltamethrin between male and female caligus. © 2014 John Wiley & Sons Ltd.

  18. Potency assays for therapeutic live whole cell cancer vaccines.

    PubMed

    Petricciani, John; Egan, William; Vicari, Giuseppe; Furesz, John; Schild, Geoffrey

    2007-04-01

    Therapeutic cancer vaccines are under development with the goal of enhancing the body's immune response to cancer cells sufficient to arrest cancer cell growth. Among the various approaches being used are those based on whole tumor cells. Developing a suitable measure of the potency of such vaccines presents a significant challenge because neither cellular associated markers nor in vivo biological responses that are correlated with efficacy have been identified; nevertheless, manufacturers and regulatory agencies will need to develop methods to evaluate these products. At this moment, the challenge for manufacturers who are developing whole cell vaccines is to demonstrate batch-to-batch consistency for the vaccine used in clinical studies and to show that comparable vaccine batches have the same capacity to achieve an acceptable level of biological activity that may be related to efficacy. This is particularly challenging in that animal models to test that activity do not exist and direct serological or immunological correlates of clinical protection are not available because protection has not yet been established in clinical trials. In the absence of well-defined biological markers and tests for manufacturing consistency, manufacturers and regulators will need to rely heavily on a highly reproducible manufacturing process--the consistency of the process therefore becomes critical. In developing regulatory approaches to whole cell cancer vaccines, the experience from the field of infectious disease vaccines should be examined for general guidance. A framework that draws heavily on the field of infectious disease vaccines is presented and suggests that at this point in the development of this new class of products, it is reasonable to develop data on quantitative antigen expression as a measure of potency with the expectation that when clinical efficacy has been established it will confirm the appropriateness of this approach. But because this will not be known until the end of a pivotal trial, a bioassay should be considered and run in parallel. Several examples of bioassays are presented along with their advantages and disadvantages. The final selection of a potency assay for use in lot release of a commercializable therapeutic whole cell vaccine ultimately will depend on the totality of the data available at the time of approval by regulatory agencies. Based on information currently available, it is likely that quantitative antigen expression or a bioassay could be used to measure potency. If both are determined to be acceptable, the use of quantitative antigen expression could be considered for routine lot release, while the bioassay could be reserved for use as one of the elements in establishing comparability when manufacturing changes are being considered after approval.

  19. Episodic acidification of small streams in the northeastern united states: Fish mortality in field bioassays

    USGS Publications Warehouse

    Van Sickle, J.; Baker, J.P.; Simonin, H.A.; Baldigo, Barry P.; Kretser, W.A.; Sharpe, W.E.

    1996-01-01

    In situ bioassays were performed as part of the Episodic Response Project, to evaluate the effects of episodic stream acidification on mortality of brook trout (Salvelinus fontinalis) and forage fish species. We report the results of 122 bioassays in 13 streams of the three study regions: the Adirondack mountains of New York, the Catskill mountains of New York, and the Northern Appalachian Plateau of Pennsylvania. Bioassays during acidic episodes had significantly higher mortality than did bioassays conducted under nonacidic conditions, but there was little difference in mortality rates in bioassays experiencing acidic episodes and those experiencing acidic conditions throughout the test period. Multiple logistic regression models were used to relate bioassay mortality rates to summary statistics of time-varying stream chemistry (inorganic monomeric aluminum, calcium, pH, and dissolved organic carbon) estimated for the 20-d bioassay periods. The large suite of candidate regressors also included biological, regional, and seasonal factors, as well as several statistics summarizing various features of aluminum exposure duration and magnitude. Regressor variable selection and model assessment were complicated by multicol-linearity and overdispersion. For the target fish species, brook trout, bioassay mortality was most closely related to time-weighted median inorganic aluminum. Median Ca and minimum pH offered additional explanatory power, as did stream-specific aluminum responses. Due to high multicollinearity, the relative importance of different aluminum exposure duration and magnitude variables was difficult to assess, but these variables taken together added no significant explanatory power to models already containing median aluminum. Between 59 and 79% of the variation in brook trout mortality was explained by models employing between one and five regressors. Simpler models were developed for smaller sets of bioassays that tested slimy and mottled sculpin (Cottus cognatus and C. bairdi) as well as blacknose dace (Rhinichthys atratulus). For these forage species a single inorganic aluminum exposure variable successfully accounted for 86-98% of the observed mortality. Even though field bioassays showed evidence of multiple toxicity factors, model results suggest that adequate mortality predictions can be obtained from a single index of inorganic Al concentrations during exposure periods.

  20. Activity Settings and Daily Routines in Preschool Classrooms: Diverse Experiences in Early Learning Settings for Low-Income Children

    ERIC Educational Resources Information Center

    Fuligni, Allison Sidle; Howes, Carollee; Huang, Yiching; Hong, Sandra Soliday; Lara-Cinisomo, Sandraluz

    2012-01-01

    This paper examines activity settings and daily classroom routines experienced by 3- and 4-year-old low-income children in public center-based preschool programs, private center-based programs, and family child care homes. Two daily routine profiles were identified using a time-sampling coding procedure: a High Free-Choice pattern in which…

  1. 32 CFR Appendix C to Part 327 - DeCA Blanket Routine Uses

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false DeCA Blanket Routine Uses C Appendix C to Part...) PRIVACY PROGRAM DEFENSE COMMISSARY AGENCY PRIVACY ACT PROGRAM Pt. 327, App. C Appendix C to Part 327—DeCA... letting of a contract, or the issuance of a license, grant, or other benefit. (c) Routine Use—Disclosure...

  2. A MAP fixed-point, packing-unpacking routine for the IBM 7094 computer

    Treesearch

    Robert S. Helfman

    1966-01-01

    Two MAP (Macro Assembly Program) computer routines for packing and unpacking fixed point data are described. Use of these routines with Fortran IV Programs provides speedy access to quantities of data which far exceed the normal storage capacity of IBM 7000-series computers. Many problems that could not be attempted because of the slow access-speed of tape...

  3. A new highly specific and robust yeast androgen bioassay for the detection of agonists and antagonists

    PubMed Central

    Helsdingen, Richard J. R.; Hamers, Astrid R. M.; van Duursen, Majorie B. M.; Nielen, Michel W. F.; Hoogenboom, Ron L. A. P.

    2007-01-01

    Public concern about the presence of natural and anthropogenic compounds which affect human health by modulating normal endocrine functions is continuously growing. Fast and simple high-throughput screening methods for the detection of hormone activities are thus indispensable. During the last two decades, a panel of different in vitro assays has been developed, mainly for compounds with an estrogenic mode of action. Here we describe the development of an androgen transcription activation assay that is easy to use in routine screening. Recombinant yeast cells were constructed that express the human androgen receptor and yeast enhanced green fluorescent protein (yEGFP), the latter in response to androgens. Compared with other reporters, the yEGFP reporter protein is very convenient because it is directly measurable in intact living cells, i.e., cell wall disruption and the addition of a substrate are not needed. When yeast was exposed to 17β-testosterone, the concentration where half-maximal activation is reached (EC50) was 50 nM. The relative androgenic potencies, defined as the ratio between the EC50 of 17β-testosterone and the EC50 of the compound, of 5α-dihydrotestosterone, methyltrienolone, and 17β-boldenone are 2.3, 1.4, and 0.15 respectively. The results presented in this paper demonstrate that this new yeast androgen bioassay is fast, sensitive, and very specific and also suited to detect compounds that have an antiandrogenic mode of action. PMID:17849102

  4. Development and validation of a streamlined method designed to detech residues of 62 veterinary drugs in bovine kidney using ultrahigh performance liquid chromatography - tandem mass spectrometry

    USDA-ARS?s Scientific Manuscript database

    In the USA, the US Department of Agriculture’s Food Safety Inspection Service (FSIS) conducts the National Residue Program designed to monitor veterinary drug and other chemical residues in beef and other slaughtered food animals. Currently, FSIS uses a 7-plate bioassay in the laboratory to screen f...

  5. Bioassays to quantify impacts of CECs in Wastewater, Surface Water, and Drinking Water : Pathway-Based In Vitro Screening

    EPA Science Inventory

    I will be giving 2 invited presentations during a 2 day meeting at Marquette University. the presentations will focus on our bioassay work on wastewater, surface water, and drinking water and bioassay work on CAFOs.

  6. Space shuttle propulsion parameter estimation using optional estimation techniques

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A regression analyses on tabular aerodynamic data provided. A representative aerodynamic model for coefficient estimation. It also reduced the storage requirements for the "normal' model used to check out the estimation algorithms. The results of the regression analyses are presented. The computer routines for the filter portion of the estimation algorithm and the :"bringing-up' of the SRB predictive program on the computer was developed. For the filter program, approximately 54 routines were developed. The routines were highly subsegmented to facilitate overlaying program segments within the partitioned storage space on the computer.

  7. EPA DSSTox and ToxCast Project Updates: Generating New ...

    EPA Pesticide Factsheets

    EPA’s National Center for Computational Toxicology is generating data and capabilities to support a new paradigm for toxicity screening and prediction. The DSSTox project is improving public access to quality structure-annotated chemical toxicity information in less summarized forms than traditionally employed in SAR modeling, and in ways that facilitate data-mining and data read-across. The DSSTox Structure-Browser provides structure searchability across the full published DSSTox toxicity-related inventory, enables linkages to and from previously isolated toxicity data resources (soon to include public microarray resources GEO, ArrayExpress, and CEBS), and provides link-outs to cross-indexed public resources such as PubChem, ChemSpider, and ACToR. The published DSSTox inventory and bioassay information also have been integrated into PubChem allowing a user to take full advantage of PubChem structure-activity and bioassay clustering features. Phase I of the ToxCastTM project has generated high-throughput screening (HTS) data from several hundred biochemical and cell-based assays for a set of 320 chemicals, mostly pesticide actives, with rich toxicology profiles. DSSTox and ACToR are providing the primary cheminformatics support for ToxCastTM and collaborative efforts with the National Toxicology Program’s HTS Program and the NIH Chemical Genomics Center. DSSTox will also be a primary vehicle for publishing ToxCastTM ToxRef summarized bioassay data for use

  8. Establishment of a bioassay for the toxicity evaluation and quality control of Aconitum herbs.

    PubMed

    Qin, Yi; Wang, Jia-bo; Zhao, Yan-ling; Shan, Li-mei; Li, Bao-cai; Fang, Fang; Jin, Cheng; Xiao, Xiao-he

    2012-01-15

    Currently, no bioassay is available for evaluating the toxicity of Aconitum herbs, which are well known for their lethal cardiotoxicity and neurotoxicity. In this study, we established a bioassay to evaluate the toxicity of Aconitum herbs. Test sample and standard solutions were administered to rats by intravenous infusion to determine their minimum lethal doses (MLD). Toxic potency was calculated by comparing the MLD. The experimental conditions of the method were optimized and standardized to ensure the precision and reliability of the bioassay. The application of the standardized bioassay was then tested by analyzing 18 samples of Aconitum herbs. Additionally, three major toxic alkaloids (aconitine, mesaconitine, and hypaconitine) in Aconitum herbs were analyzed using a liquid chromatographic method, which is the current method of choice for evaluating the toxicity of Aconitum herbs. We found that for all Aconitum herbs, the total toxicity of the extract was greater than the toxicity of the three alkaloids. Therefore, these three alkaloids failed to account for the total toxicity of Aconitum herbs. Compared with individual chemical analysis methods, the chief advantage of the bioassay is that it characterizes the total toxicity of Aconitum herbs. An incorrect toxicity evaluation caused by quantitative analysis of the three alkaloids might be effectively avoided by performing this bioassay. This study revealed that the bioassay is a powerful method for the safety assessment of Aconitum herbs. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Impact of Spodoptera frugiperda neonate pretreatment conditions on Vip3Aa19 insecticidal protein activity and laboratory bioassay variation.

    PubMed

    Da Silva, Karen F; Spencer, Terence A; Camargo Gil, Carolina; Siegfried, Blair D; Walters, Frederick S

    2016-04-01

    Variation in response to insecticidal proteins is common upon repetition of insect bioassays. Understanding this variation is a prerequisite to detecting biologically important differences. We tracked neonate Spodoptera frugiperda (J.E. Smith) susceptibility to Vip3Aa19 over 17 generations using standardized bioassay methods. Five larval pretreatment conditions and one bioassay condition were tested to determine whether susceptibility was affected. These included: storage time; prefeeding; storage at reduced temperature; storage at reduced humidity; colony introgression of field-collected individuals. Extremes of photoperiod during the bioassay itself were also examined. LC50 values for two strains of S. frugiperda varied 6.6-fold or 8.8-fold over 17 generations. Storage time and humidity had no impact on Vip3Aa19 susceptibility, whereas prefeeding significantly reduced subsequent mortality (by 27%). Storage at reduced temperature increased mortality for one colony (from 45.6 to 73.0%) but not for the other. Introgression of field-collected individuals affected susceptibility at the first generation but not for subsequent generations. A 24 h bioassay photophase significantly reduced susceptibility (by 26%) for both colonies. Certain pretreatment and bioassay conditions were identified that can affect S. frugiperda Vip3Aa19 susceptibility, but innate larval heterogeneity was also present. Our observations should help to increase the consistency of insecticidal protein bioassay results. © 2015 Syngenta Crop Protection, LLC. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  10. Evaluation of Reduced Sediment Volume Procedures for Acute Toxicity Tests Using the Estuarine Amphipod Leptocheirus plumulosus

    EPA Science Inventory

    The volume of sediment required to perform a sediment toxicity bioassay is a major driver of the overall cost associated with that bioassay. Sediment volume affects bioassay cost due to sediment collection, transportation, storage, and disposal costs as well as labor costs assoc...

  11. Bioassay criteria for environmental restoration workers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, E.H.; Bihl, D.E.

    1993-01-01

    Environmental restoration (ER) work at the U. S. Department of Energy Hanford Site posed questions concerning when to perform bioassay monitoring of workers for potential intakes of radioactivity. Application of criteria originally developed for use inside radionuclide processing facilities to ER work resulted in overly restrictive bioassay requirements. ER work typically involves site characterization or, excavating large quantities of potentially contaminated soil, rather than working with concentrated quantities of radioactivity as in a processing facility. An improved approach, tailored to ER work, provided soil contamination concentrations above which worker bioassay would be required. Soil concentrations were derived assuming acute ormore » chronic intakes of 2% of an Annual Limit on Intake (ALI), or a potential committed effective dose equivalent of 100 mrem, and conservative dust loading of air from the work. When planning ER work, the anticipated soil concentration and corresponding need for bioassay could be estimated from work-site historical records. Once site work commenced, soil sampling and work-place surveys could be used to determine bioassay needs. This approach substantially reduced the required number of bioassay samples with corresponding reductions in analytical costs, schedules, and more flexible work-force management. (Work supported by the US Department of Energy under contract DOE-AC06-76RLO 1830.)« less

  12. GEMPAK: An arbitrary aircraft geometry generator

    NASA Technical Reports Server (NTRS)

    Stack, S. H.; Edwards, C. L. W.; Small, W. J.

    1977-01-01

    A computer program, GEMPAK, has been developed to aid in the generation of detailed configuration geometry. The program was written to allow the user as much flexibility as possible in his choices of configurations and the detail of description desired and at the same time keep input requirements and program turnaround and cost to a minimum. The program consists of routines that generate fuselage and planar-surface (winglike) geometry and a routine that will determine the true intersection of all components with the fuselage. This paper describes the methods by which the various geometries are generated and provides input description with sample input and output. Also included are descriptions of the primary program variables and functions performed by the various routines. The FORTRAN program GEMPAK has been used extensively in conjunction with interfaces to several aerodynamic and plotting computer programs and has proven to be an effective aid in the preliminary design phase of aircraft configurations.

  13. An adaptive staircase procedure for the E-Prime programming environment.

    PubMed

    Hairston, W David; Maldjian, Joseph A

    2009-01-01

    Many studies need to determine a subject's threshold for a given task. This can be achieved efficiently using an adaptive staircase procedure. While the logic and algorithms for staircases have been well established, the few pre-programmed routines currently available to researchers require at least moderate programming experience to integrate into new paradigms and experimental settings. Here, we describe a freely distributed routine developed for the E-Prime programming environment that can be easily integrated into any experimental protocol with only a basic understanding of E-Prime. An example experiment (visual temporal-order-judgment task) where subjects report the order of occurrence of two circles illustrates the behavior and consistency of the routine.

  14. Effects of an In-Service Training Program Using the Routines-Based Interview

    ERIC Educational Resources Information Center

    Boavida, Tânia; Aguiar, Cecília; McWilliam, R. A.; Correia, Nadine

    2016-01-01

    The focus of this study is an in-service training program rooted in routines-based early intervention and designed to improve the quality of goals and objectives on individualized plans. Participants were local intervention team members and other professionals who worked closely with each team. This training program involved a small number of…

  15. The medical story. [of Skylab

    NASA Technical Reports Server (NTRS)

    Johnston, R. S.; Dietlein, L. F.; Michel, E. L.

    1975-01-01

    The paper discusses the medical program of the Skylab missions. The major medical systems discussed include the food system, the waste-management system, the personal-hygiene system, and the inflight medical support system. The life-sciences experiments conducted on Skylab are reviewed. These dealt with the cardiovascular system, mineral balance and bioassay of fluids, sleep, blood, metabolic activity, vestibular function, and time and motion studies. The medical operations were accomplished with only minor problems.

  16. Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure.

    PubMed

    Maxim, L Daniel; Utell, Mark J

    2018-02-01

    This literature review on refractory ceramic fibers (RCF) summarizes relevant information on manufacturing, processing, applications, occupational exposure, toxicology and epidemiology studies. Rodent toxicology studies conducted in the 1980s showed that RCF caused fibrosis, lung cancer and mesothelioma. Interpretation of these studies was difficult for various reasons (e.g. overload in chronic inhalation bioassays), but spurred the development of a comprehensive product stewardship program under EPA and later OSHA oversight. Epidemiology studies (both morbidity and mortality) were undertaken to learn more about possible health effects resulting from occupational exposure. No chronic animal bioassay studies on RCF have been conducted since the 1980s. The results of the ongoing epidemiology studies confirm that occupational exposure to RCF is associated with the development of pleural plaques and minor decrements in lung function, but no interstitial fibrosis or incremental lung cancer. Evidence supporting a finding that urinary tumors are associated with RCF exposure remains, but is weaker. One reported, but unconfirmed, mesothelioma was found in an individual with prior occupational asbestos exposure. An elevated SMR for leukemia was found, but was absent in the highly exposed group and has not been observed in studies of other mineral fibers. The industry will continue the product stewardship program including the mortality study.

  17. International Program to Monitor Cat Flea Populations for Susceptibility to Imidacloprid.

    PubMed

    Rust, M K; Blagburn, B L; Denholm, I; Dryden, M W; Payne, P; Hinkle, N C; Kopp, S; Williamson, M

    2018-06-20

    An international team of scientists and veterinarians was assembled in 1999 to develop a monitoring program to determine the susceptibility of cat fleas, Ctenocephalides felis felis (Bouché) (Siphonaptera: Pulicidae), to imidacloprid. Cat flea eggs were collected, shipped to laboratories, and tested for their susceptibility to imidacloprid. Over 3,000 C. felis populations were collected from 2002 to 2017 from 10 different countries. Of these, 66.3% were collected from cats and 33.7% from dogs. C. f. felis populations (n = 2,200) were bioassayed by exposing cat flea eggs and the emerging larvae to a Diagnostic Dose (DD) of 3 ppm imidacloprid in larval rearing medium. Flea eggs hatched and developed in the untreated controls in 1,837 of the isolates (83.5%) bioassayed. Flea isolates (n = 61) that had ≥5% survival at the DD of 3 ppm were retested with a second DD of 3 ppm. None of them had ≥5% survival to the second dose of 3 ppm. Of the 1,837 valid C. felis isolates tested, there has been no evidence of a decreased susceptibility to imidacloprid over the past 17 yr. The methods outlined in this article should provide an acceptable protocol for testing many of the new active ingredients that have been registered for cat flea control.

  18. Resistance monitoring of Heliothis virescens to pyramided cotton varieties with a hydrateable, artificial cotton leaf bioassay

    USDA-ARS?s Scientific Manuscript database

    Proof of concept was demonstrated for a practical, off the shelf bioassay to monitor for tobacco budworm resistance to pyramided Bt cotton using plant eluants. The bioassay was based on a previously described feeding disruption test using hydrateable artificial diet containing a blue indicator dye, ...

  19. Bioassay of formulations of Bacillus thuringiensis for use in forestry: panel discussion of the role of the bioassay in standardizing formulations of B. thuringiensis

    Treesearch

    H. T. Dulmage; C. C. Beegle; N. R. Dubois

    1985-01-01

    The panel discussed various aspects of Bacillus thuringiensis formulations and fermentations and concluded that the only means at present of standardizing these formulations or discovering more potent strains of the Bacillus is through carefully controlled bioassays.

  20. Validation of a Novel Bioassay for Low-level Perchlorate Determination

    DTIC Science & Technology

    2014-04-01

    was not attractive, since these reduce PMS2 , and it was thought they would interfere with the stoichiometry of NADH and perchlorate in the bioassay...these reduce PMS2 directly, and would interfere with the stoichiometry of NADH and perchlorate in the bioassay. Thus the only approach that could be

  1. Validation of a Novel Bioassay for Low-level Perchlorate Determination

    DTIC Science & Technology

    2013-05-01

    since these reduce PMS2 , and it was thought they would interfere with the stoichiometry of NADH and perchlorate in the bioassay. With regard to the...reduce PMS2 directly, and would interfere with the stoichiometry of NADH and perchlorate in the bioassay. Thus the only approach that could be

  2. [The National Vaccine Injury Compensation Program in Japan].

    PubMed

    Ihara, Toshiaki

    2011-09-01

    Two vaccination systems have been employed in Japan, the routine vaccination and the voluntary vaccination. The National Vaccine Injury Compensation Program in Japan is no-fault system. Claims after the routine vaccination are demanded to the Ministry of Health, Labour and Welfare through local governments, and compensation is more expenses. Meanwhile, claims after the voluntary vaccination are demanded to the Pharmaceuticals and Medical Device Agency directly, and compensation is less compared with the routine vaccination.

  3. PubChem BioAssay: 2017 update

    PubMed Central

    Wang, Yanli; Bryant, Stephen H.; Cheng, Tiejun; Wang, Jiyao; Gindulyte, Asta; Shoemaker, Benjamin A.; Thiessen, Paul A.; He, Siqian; Zhang, Jian

    2017-01-01

    PubChem's BioAssay database (https://pubchem.ncbi.nlm.nih.gov) has served as a public repository for small-molecule and RNAi screening data since 2004 providing open access of its data content to the community. PubChem accepts data submission from worldwide researchers at academia, industry and government agencies. PubChem also collaborates with other chemical biology database stakeholders with data exchange. With over a decade's development effort, it becomes an important information resource supporting drug discovery and chemical biology research. To facilitate data discovery, PubChem is integrated with all other databases at NCBI. In this work, we provide an update for the PubChem BioAssay database describing several recent development including added sources of research data, redesigned BioAssay record page, new BioAssay classification browser and new features in the Upload system facilitating data sharing. PMID:27899599

  4. A versatile electrowetting-based digital microfluidic platform for quantitative homogeneous and heterogeneous bio-assays

    NASA Astrophysics Data System (ADS)

    Vergauwe, Nicolas; Witters, Daan; Ceyssens, Frederik; Vermeir, Steven; Verbruggen, Bert; Puers, Robert; Lammertyn, Jeroen

    2011-05-01

    Electrowetting-on-dielectric (EWOD) lab-on-a-chip systems have already proven their potential within a broad range of bio-assays. Nevertheless, research on the analytical performance of those systems is limited, yet crucial for a further breakthrough in the diagnostic field. Therefore, this paper presents the intrinsic possibilities of an EWOD lab-on-a-chip as a versatile platform for homogeneous and heterogeneous bio-assays with high analytical performance. Both droplet dispensing and splitting cause variations in droplet size, thereby directly influencing the assay's performance. The extent to which they influence the performance is assessed by a theoretical sensitivity analysis, which allows the definition of a basic framework for the reduction of droplet size variability. Taking advantage of the optimized droplet manipulations, both homogeneous and heterogeneous bio-assays are implemented in the EWOD lab-on-a-chip to demonstrate the analytical capabilities and versatility of the device. A fully on-chip enzymatic assay is realized with high analytical performance. It demonstrates the promising capabilities of an EWOD lab-on-a-chip in food-related and medical applications, such as nutritional and blood analyses. Further, a magnetic bio-assay for IgE detection using superparamagnetic nanoparticles is presented whereby the nanoparticles are used as solid carriers during the bio-assay. Crucial elements are the precise manipulation of the superparamagnetic nanoparticles with respect to dispensing and separation. Although the principle of using nano-carriers is demonstrated for protein detection, it can be easily extended to a broader range of bio-related applications like DNA sensing. In heterogeneous bio-assays the chip surface is actively involved during the execution of the bio-assay. Through immobilization of specific biological compounds like DNA, proteins and cells a reactive chip surface is realized, which enhances the bio-assay performance. To demonstrate this potential, on-chip adhesion islands are fabricated to immobilize MCF-7 human breast cancer cells. Viability studies are performed to assess the functionalization efficiency.

  5. In vitro bioassays for detecting dioxin-like activity--application potentials and limits of detection, a review.

    PubMed

    Eichbaum, Kathrin; Brinkmann, Markus; Buchinger, Sebastian; Reifferscheid, Georg; Hecker, Markus; Giesy, John P; Engwall, Magnus; van Bavel, Bert; Hollert, Henner

    2014-07-15

    Use of in vitro assays as screening tool to characterize contamination of a variety of environmental matrices has become an increasingly popular and powerful toolbox in the field of environmental toxicology. While bioassays cannot entirely substitute analytical methods such as gas chromatography-mass spectrometry (GC-MS), the increasing improvement of cell lines and standardization of bioassay procedures enhance their utility as bioanalytical pre-screening tests prior to more targeted chemical analytical investigations. Dioxin-receptor-based assays provide a holistic characterization of exposure to dioxin-like compounds (DLCs) by integrating their overall toxic potential, including potentials of unknown DLCs not detectable via e.g. GC-MS. Hence, they provide important additional information with respect to environmental risk assessment of DLCs. This review summarizes different in vitro bioassay applications for detection of DLCs and considers the comparability of bioassay and chemical analytically derived toxicity equivalents (TEQs) of different approaches and various matrices. These range from complex samples such as sediments through single reference to compound mixtures. A summary of bioassay derived detection limits (LODs) showed a number of current bioassays to be equally sensitive as chemical methodologies, but moreover revealed that most of the bioanalytical studies conducted to date did not report their LODs, which represents a limitation with regard to low potency samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data.

    PubMed

    Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

    2016-05-01

    Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Quantitative structure-activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro-in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and big data. Environ Health Perspect 124:634-641; http://dx.doi.org/10.1289/ehp.1509763.

  7. Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data

    PubMed Central

    Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

    2015-01-01

    Background: Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. Objective: The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Methods: Quantitative structure–activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro–in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. Results: The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Conclusion: Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Citation: Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and big data. Environ Health Perspect 124:634–641; http://dx.doi.org/10.1289/ehp.1509763 PMID:26383846

  8. NEW COLUMN SEPARATION METHOD FOR EMERGENCY URINE SAMPLES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maxwell, S; Brian Culligan, B

    2007-08-28

    The Savannah River Site Environmental Bioassay Lab participated in the 2007 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2007. A new rapid column separation method was applied directly to the NRIP 2007 emergency urine samples, with only minimal sample preparation to reduce preparation time. Calcium phosphate precipitation, previously used to pre-concentrate actinides and Sr-90 in NRIP 2006 urine and water samples, was not used for the NRIP 2007 urine samples. Instead, the raw urine was acidified and passed directly through the stacked resin columns (TEVA+TRU+SR Resins) to separate the actinides andmore » strontium from the NRIP urine samples more quickly. This improvement reduced sample preparation time for the NRIP 2007 emergency urine analyses significantly. This approach works well for small volume urine samples expected during an emergency response event. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and strontium-90 analyses for NRIP 2007 urine samples.« less

  9. COMPARISON OF BIOASSAY AND ENZYME-LINKED IMMUNOSORBENT ASSAY FOR QUANTIFICATION OF 'SPODOPTERA FRUGIPERDA' NUCLEAR POLYHEDROSIS VIRUS IN SOIL

    EPA Science Inventory

    Standard curves with known amounts of Spodoptera frugiperda nuclear polyhedrosis virus (NPV) in soil were established with a bioassay and with an enzyme-linked immunosorbent assay (ELISA). The bioassay detected as few as 4 x 10 to the 4th power polyhedral inclusion bodies (PIB)/g...

  10. Two case studies of highly insoluble plutonium inhalation with implications for bioassay.

    PubMed

    Carbaugh, E H; La Bone, T R

    2003-01-01

    Two well characterised Pu inhalation cases show some remarkable similarities between substantially different types of Pu oxide. The circumstances of exposure, therapy, bioassay data, chemical solubility studies and dosimetry associated with these cases suggest that highly insoluble Pu may be more common than previously thought, and can pose significant challenges to bioassay programmes.

  11. Bioassay vs. Air Sampling: Practical Guidance and Experience at Hanford

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Carlson, Eric W.; Hill, Robin L.

    2004-02-08

    The Hanford Site has implemented a policy to guide in determining whether air sampling data or special fecal bioassay data are more appropriate for determining doses of record for low-level plutonium exposures. The basis for the policy and four years of experience in comparing DAC-hours exposure with bioassay-based dosimetry is discussed.

  12. UTILITY OF A FULL LIFE-CYCLE COPEPOD BIOASSAY APPROACH FOR ASSESSMENT OF SEDIMENT-ASSOCIATED CONTAMINANT MIXTURES. (R825279)

    EPA Science Inventory

    Abstract

    We compared a 21 day full life-cycle bioassay with an existing 14 day partial life-cycle bioassay for two species of meiobenthic copepods, Microarthridion littorale and Amphiascus tenuiremis. We hypothesized that full life-cycle tests would bette...

  13. Comparing routine neurorehabilitation program with trunk exercises based on Bobath concept in multiple sclerosis: pilot study.

    PubMed

    Keser, Ilke; Kirdi, Nuray; Meric, Aydin; Kurne, Asli Tuncer; Karabudak, Rana

    2013-01-01

    This study compared trunk exercises based on the Bobath concept with routine neurorehabilitation approaches in multiple sclerosis (MS). Bobath and routine neurorehabilitation exercises groups were evaluated. MS cases were divided into two groups. Both groups joined a 3 d/wk rehabilitation program for 8 wk. The experimental group performed trunk exercises based on the Bobath concept, and the control group performed routine neurorehabilitation exercises. Additionally, both groups performed balance and coordination exercises. All patients were evaluated with the Trunk Impairment Scale (TIS), Berg Balance Scale (BBS), International Cooperative Ataxia Rating Scale (ICARS), and Multiple Sclerosis Functional Composite (MSFC) before and after the physiotherapy program. In group analysis, TIS, BBS, ICARS, and MSFC scores and strength of abdominal muscles were significantly different after treatment in both groups (p < 0.05). When the groups were compared, no significant differences were found in any parameters (p > 0.05). Although trunk exercises based on the Bobath concept are rarely applied in MS rehabilitation, the results of this study show that they are as effective as routine neurorehabilitation exercises. Therefore, trunk exercises based on the Bobath concept can be beneficial in MS rehabilitation programs.

  14. The limits of two-year bioassay exposure regimens for identifying chemical carcinogens.

    PubMed

    Huff, James; Jacobson, Michael F; Davis, Devra Lee

    2008-11-01

    Chemical carcinogenesis bioassays in animals have long been recognized and accepted as valid predictors of potential cancer hazards to humans. Most rodent bioassays begin several weeks after birth and expose animals to chemicals or other substances, including workplace and environmental pollutants, for 2 years. New findings indicate the need to extend the timing and duration of exposures used in the rodent bioassay. In this Commentary, we propose that the sensitivity of chemical carcinogenesis bio-assays would be enhanced by exposing rodents beginning in utero and continuing for 30 months (130 weeks) or until their natural deaths at up to about 3 years. Studies of three chemicals of different structures and uses-aspartame, cadmium, and toluene-suggest that exposing experimental animals in utero and continuing exposure for 30 months or until their natural deaths increase the sensitivity of bioassays, avoid false-negative results, and strengthen the value and validity of results for regulatory agencies. Government agencies, drug companies, and the chemical industry should conduct and compare the results of 2-year bioassays of known carcinogens or chemicals for which there is equivocal evidence of carcinogenicity with longer-term studies, with and without in utero exposure. If studies longer than 2 years and/or with in utero exposure are found to better identify potential human carcinogens, then regulatory agencies should promptly revise their testing guidelines, which were established in the 1960s and early 1970s. Changing the timing and dosing of the animal bioassay would enhance protection of workers and consumers who are exposed to potentially dangerous workplace or home contaminants, pollutants, drugs, food additives, and other chemicals throughout their lives.

  15. The Limits of Two-Year Bioassay Exposure Regimens for Identifying Chemical Carcinogens

    PubMed Central

    Huff, James; Jacobson, Michael F.; Davis, Devra Lee

    2008-01-01

    Background Chemical carcinogenesis bioassays in animals have long been recognized and accepted as valid predictors of potential cancer hazards to humans. Most rodent bioassays begin several weeks after birth and expose animals to chemicals or other substances, including workplace and environmental pollutants, for 2 years. New findings indicate the need to extend the timing and duration of exposures used in the rodent bioassay. Objectives In this Commentary, we propose that the sensitivity of chemical carcinogenesis bio-assays would be enhanced by exposing rodents beginning in utero and continuing for 30 months (130 weeks) or until their natural deaths at up to about 3 years. Discussion Studies of three chemicals of different structures and uses—aspartame, cadmium, and toluene—suggest that exposing experimental animals in utero and continuing exposure for 30 months or until their natural deaths increase the sensitivity of bioassays, avoid false-negative results, and strengthen the value and validity of results for regulatory agencies. Conclusions Government agencies, drug companies, and the chemical industry should conduct and compare the results of 2-year bioassays of known carcinogens or chemicals for which there is equivocal evidence of carcinogenicity with longer-term studies, with and without in utero exposure. If studies longer than 2 years and/or with in utero exposure are found to better identify potential human carcinogens, then regulatory agencies should promptly revise their testing guidelines, which were established in the 1960s and early 1970s. Changing the timing and dosing of the animal bioassay would enhance protection of workers and consumers who are exposed to potentially dangerous workplace or home contaminants, pollutants, drugs, food additives, and other chemicals throughout their lives. PMID:19057693

  16. Evaluation of the toxicity of two soils from Jales Mine (Portugal) using aquatic bioassays.

    PubMed

    Loureiro, Susana; Ferreira, Abel L G; Soares, Amadeu M V M; Nogueira, António J A

    2005-10-01

    Soil contamination can be one path for streams and groundwater contamination. As a complement of chemical analysis and total contaminants determination, bioassays can provide information on the bioavailable fraction of chemical compounds, focusing on the retention and habitat function of soils. In this study the evaluation of the toxicity of two soils from the abandoned Jales Mine (Portugal) regarded both functions. The buffer capacity of soils was tested with bioassays carried out using the cladoceran Daphnia magna and the marine bacteria Vibrio fischeri. The habitat function of soils was evaluated with the reproduction bioassay with the collembolan Folsomia candida. The Microtox solid-phase test was performed with V. fischeri using soil as test medium, and soil elutriates were extracted to perform the Microtox basic test, and an immobilization and reproduction bioassay with D. magna. The marine bacteria showed high sensitivity to the soil with low heavy metal content (JNC soil) and to JNC soil elutriates, while the soil with highest heavy metal content (JC soil) or soil elutriates exposure did not cause any toxic effect. In the bioassays with D. magna, organisms showed sensitivity to JNC and also to JC soil elutriates. Both mobilization and reproduction features were inhibited. The bioassay with F. candida did not reflect any influence of the contaminants on their reproduction. Although JNC soil presented lower heavy metal contents, elutriates showed different patterns of contamination when compared to JC soil and elutriates, which indicates different retention and buffer capacities between soils. Results obtained in this study underlined the sensitivity and importance of soil elutriate bioassays with aquatic organisms in the evaluation strategy in soil ERA processes.

  17. Analysis of the sensitivity of in vitro bioassays for androgenic, progestagenic, glucocorticoid, thyroid and estrogenic activity: Suitability for drinking and environmental waters.

    PubMed

    Leusch, Frederic D L; Neale, Peta A; Hebert, Armelle; Scheurer, Marco; Schriks, Merijn C M

    2017-02-01

    The presence of endocrine disrupting chemicals in the aquatic environment poses a risk for ecosystem health. Consequently there is a need for sensitive tools, such as in vitro bioassays, to monitor endocrine activity in environmental waters. The aim of the current study was to assess whether current in vitro bioassays are suitable to detect endocrine activity in a range of water types. The reviewed assays included androgenic (n=11), progestagenic (n=6), glucocorticoid (n=5), thyroid (n=5) and estrogenic (n=8) activity in both agonist and antagonist mode. Existing in vitro bioassay data were re-evaluated to determine assay sensitivity, with the calculated method detection limit compared with measured hormonal activity in treated wastewater, surface water and drinking water to quantify whether the studied assays were sufficiently sensitive for environmental samples. With typical sample enrichment, current in vitro bioassays are sufficiently sensitive to detect androgenic activity in treated wastewater and surface water, with anti-androgenic activity able to be detected in most environmental waters. Similarly, with sufficient enrichment, the studied mammalian assays are able to detect estrogenic activity even in drinking water samples. Fewer studies have focused on progestagenic and glucocorticoid activity, but some of the reviewed bioassays are suitable for detecting activity in treated wastewater and surface water. Even less is known about (anti)thyroid activity, but the available data suggests that the more sensitive reviewed bioassays are still unlikely to detect this type of activity in environmental waters. The findings of this review can help provide guidance on in vitro bioassay selection and required sample enrichment for optimised detection of endocrine activity in environmental waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. A new P. putida instrumental toxicity bioassay.

    PubMed

    Figueredo, Federico; Abrevaya, Ximena C; Cortón, Eduardo

    2015-05-01

    Here, we present a new toxicity bioassay (CO2-TOX), able to detect toxic or inhibitory compounds in water samples, based on the quantification of Pseudomonas putida KT2440 CO2 production. The metabolically produced CO2 was measured continuously and directly in the liquid assay media, with a potentiometric gas electrode. The optimization studies were performed using as a model toxicant 3,5-DCP (3,5-dichlorophenol); later, heavy metals (Pb(2+), Cu(2+), or Zn(2+)) and a metalloid (As(5+)) were assayed. The response to toxics was evident after 15 min of incubation and at relatively low concentrations (e.g., 1.1 mg/L of 3,5-DCP), showing that the CO2-TOX bioassay is fast and sensitive. The EC50 values obtained were 4.93, 0.12, 6.05, 32.17, and 37.81 mg/L for 3,5-DCP, Cu(2+), Zn(2+), As(5+), and Pb(2+), respectively, at neutral pH. Additionally, the effect of the pH of the sample and the use of lyophilized bacteria were also analyzed showing that the bioassay can be implemented in different conditions. Moreover, highly turbid samples and samples with very low oxygen levels were measured successfully with the new instrumental bioassay described here. Finally, simulated samples containing 3,5-DCP or a heavy metal mixture were tested using the proposed bioassay and a standard ISO bioassay, showing that our test is more sensible to the phenol but less sensible to the metal mixtures. Therefore, we propose CO2-TOX as a rapid, sensitive, low-cost, and robust instrumental bioassay that could perform as an industrial wastewater-process monitor among other applications.

  19. MAIL LOG, program theory, volume 2

    NASA Technical Reports Server (NTRS)

    Harris, D. K.

    1979-01-01

    Information relevant to the MAIL LOG program theory is documented. The L-files for mail correspondence, design information release/report, and the drawing/engineering order are given. In addition, sources for miscellaneous external routines and special support routines are documented along with a glossary of terms.

  20. Biomonitoring of cyanotoxins in two tropical reservoirs by cladoceran toxicity bioassays.

    PubMed

    da S Ferrão-Filho, Aloysio; Soares, Maria Carolina S; de Freitas Magalhães, Valeria; Azevedo, Sandra M F O

    2009-02-01

    This study evaluates the potential for the use of cladocerans in biomonitoring of cyanobacterial toxins. Two zooplankton species (Daphnia gessneri and Moina micrura) were cultivated in the laboratory for use in acute (48 h) and chronic (10 days) bioassays. Water samples were collected from two reservoirs and diluted in mineral water at four concentrations. Survivorship in the acute bioassays was used to calculate LC50, and survivorship and fecundity in chronic bioassays were used to calculate the intrinsic population growth rate (r) and the EC50. Analysis of phytoplankton in the water samples from one reservoir revealed that cyanobacteria were the dominant group, represented by the genera Anabaena, Cylindrospermopsis, and Microcystis. Results of bioassays showed adverse effects including death, paralysis, and reduced population growth rate, generally proportional to the reservoir water concentration. These effects may be related to the presence of cyanobacteria toxins (microcystins or saxitoxins) in the water.

  1. Ceramic material life prediction: A program to translate ANSYS results to CARES/LIFE reliability analysis

    NASA Technical Reports Server (NTRS)

    Vonhermann, Pieter; Pintz, Adam

    1994-01-01

    This manual describes the use of the ANSCARES program to prepare a neutral file of FEM stress results taken from ANSYS Release 5.0, in the format needed by CARES/LIFE ceramics reliability program. It is intended for use by experienced users of ANSYS and CARES. Knowledge of compiling and linking FORTRAN programs is also required. Maximum use is made of existing routines (from other CARES interface programs and ANSYS routines) to extract the finite element results and prepare the neutral file for input to the reliability analysis. FORTRAN and machine language routines as described are used to read the ANSYS results file. Sub-element stresses are computed and written to a neutral file using FORTRAN subroutines which are nearly identical to those used in the NASCARES (MSC/NASTRAN to CARES) interface.

  2. Families Experiencing Housing Instability: The Effects of Housing Programs on Family Routines and Rituals

    PubMed Central

    Mayberry, Lindsay S.; Shinn, Marybeth; Benton, Jessica Gibbons; Wise, Jasmine

    2013-01-01

    Maintenance of family processes can protect parents, children, and families from the detrimental effects of extreme stressors, such as homelessness. When families cannot maintain routines and rituals, the stressors of poverty and homelessness can be compounded for both caregivers and children. However, characteristics of living situations common among families experiencing homelessness present barriers to the maintenance of family routines and rituals. We analyzed 80 in-depth interviews with parents who were experiencing or had recently experienced an instance of homelessness. We compared their assessments of challenges to family schedules, routines, and rituals across various living situations, including shelter, transitional housing programs, doubled up (i.e. living temporarily with family/friend), and independent housing. Rules common across shelters and transitional housing programs impeded family processes, and parents felt surveilled and threatened with child protective service involvement in these settings. In doubled up living situations, parents reported adapting their routines to those of the household and having parenting interrupted by opinions of friends and family members. Families used several strategies to maintain family rituals and routines in these living situations and ensure consistency and stability for their children during an otherwise unstable time. PMID:24826832

  3. Families experiencing housing instability: the effects of housing programs on family routines and rituals.

    PubMed

    Mayberry, Lindsay Satterwhite; Shinn, Marybeth; Benton, Jessica Gibbons; Wise, Jasmine

    2014-01-01

    Maintenance of family processes can protect parents, children, and families from the detrimental effects of extreme stressors, such as homelessness. When families cannot maintain routines and rituals, the stressors of poverty and homelessness can be compounded for both caregivers and children. However, characteristics of living situations common among families experiencing homelessness present barriers to the maintenance of family routines and rituals. We analyzed 80 in-depth interviews with parents who were experiencing or had recently experienced an instance of homelessness. We compared their assessments of challenges to family schedules, routines, and rituals across various living situations, including shelter, transitional housing programs, doubled-up (i.e., living temporarily with family or friends), and independent housing. Rules common across shelters and transitional housing programs impeded family processes, and parents felt surveilled and threatened with child protective service involvement in these settings. In doubled-up living situations, parents reported adapting their routines to those of the household and having parenting interrupted by opinions of friends and family members. Families used several strategies to maintain family routines and rituals in these living situations and ensure consistency and stability for their children during an otherwise unstable time. (c) 2014 APA, all rights reserved.

  4. Prediction of rodent carcinogenicity bioassays from molecular structure using inductive logic programming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, R.D.; Srinivasan, A.

    1996-10-01

    The machine learning program Progol was applied to the problem of forming the structure-activity relationship (SAR) for a set of compounds tested for carcinogenicity in rodent bioassays by the U.S. National Toxicology Program (NTP). Progol is the first inductive logic programming (ILP) algorithm to use a fully relational method for describing chemical structure in SARs, based on using atoms and their bond connectivities. Progol is well suited to forming SARs for carcinogenicity as it is designed to produce easily understandable rules (structural alerts) for sets of noncongeneric compounds. The Progol SAR method was tested by prediction of a set ofmore » compounds that have been widely predicted by other SAR methods (the compounds used in the NTP`s first round of carcinogenesis predictions). For these compounds no method (human or machine) was significantly more accurate than Progol. Progol was the most accurate method that did not use data from biological tests on rodents (however, the difference in accuracy is not significant). The Progol predictions were based solely on chemical structure and the results of tests for Salmonella mutagenicity. Using the full NTP database, the prediction accuracy of Progol was estimated to be 63% ({+-}3%) using 5-fold cross validation. A set of structural alerts for carcinogenesis was automatically generated and the chemical rationale for them investigated-these structural alerts are statistically independent of the Salmonella mutagenicity. Carcinogenicity is predicted for the compounds used in the NTP`s second round of carcinogenesis predictions. The results for prediction of carcinogenesis, taken together with the previous successful applications of predicting mutagenicity in nitroaromatic compounds, and inhibition of angiogenesis by suramin analogues, show that Progol has a role to play in understanding the SARs of cancer-related compounds. 29 refs., 2 figs., 4 tabs.« less

  5. SLHAplus: A library for implementing extensions of the standard model

    NASA Astrophysics Data System (ADS)

    Bélanger, G.; Christensen, Neil D.; Pukhov, A.; Semenov, A.

    2011-03-01

    We provide a library to facilitate the implementation of new models in codes such as matrix element and event generators or codes for computing dark matter observables. The library contains an SLHA reader routine as well as diagonalisation routines. This library is available in CalcHEP and micrOMEGAs. The implementation of models based on this library is supported by LanHEP and FeynRules. Program summaryProgram title: SLHAplus_1.3 Catalogue identifier: AEHX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHX_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 6283 No. of bytes in distributed program, including test data, etc.: 52 119 Distribution format: tar.gz Programming language: C Computer: IBM PC, MAC Operating system: UNIX (Linux, Darwin, Cygwin) RAM: 2000 MB Classification: 11.1 Nature of problem: Implementation of extensions of the standard model in matrix element and event generators and codes for dark matter observables. Solution method: For generic extensions of the standard model we provide routines for reading files that adopt the standard format of the SUSY Les Houches Accord (SLHA) file. The procedure has been generalized to take into account an arbitrary number of blocks so that the reader can be used in generic models including non-supersymmetric ones. The library also contains routines to diagonalize real and complex mass matrices with either unitary or bi-unitary transformations as well as routines for evaluating the running strong coupling constant, running quark masses and effective quark masses. Running time: 0.001 sec

  6. 9 CFR 147.16 - Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Procedure for the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). 147.16 Section 147.16 Animals and Animal Products... the evaluation of mycoplasma reactors by in vivo bio-assay (enrichment). This procedure has been shown...

  7. 9 CFR 147.6 - Procedure for determining the status of flocks reacting to tests for Mycoplasma gallisepticum...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agency may examine reactors by the in vivo bio-assay, PCR-based procedures, and/or culture procedures before final determination of the flock status is made. (13) If the in vivo bio-assay, PCR-based... classification for which it was tested. (14) If the in vivo bio-assay, PCR-based procedures, or culture...

  8. A bioaccumulation bioassay for freshwater sediments

    USGS Publications Warehouse

    Mac, Michael J.; Noguchi, George E.; Hesselberg, Robert J.; Edsall, Carol C.; Shoesmith, John A.; Bowker, James D.

    1990-01-01

    A laboratory bioassay is described for determining the bioavailability of contaminants from freshwater sediments. The bioassay consists of 10-d exposures to whole sediments under flow-through conditions. After testing five species, the fathead minnow (Pimephales promelas) and the earthworm (Lubricus terrestris) were recommended for use in the test. When the availability of polychlorinated biphenyls (PCBs), Hg and Zn from Great Lakes sediments was examined in laboratory exposures, only the PCBs were accumulated. A field validation study demonstrated that the magnitude of accumulation in laboratory exposures was similar to that in organisms caged in the field. A protocol is recommended for using the test as a standardized bioaccumulation bioassay.

  9. The use of cryopreserved sea urchin embryos (Paracentrotus lividus) in marine quality assessment.

    PubMed

    Paredes, E; Bellas, J

    2015-06-01

    We have established for first time an ecotoxicological bioassay using cryopreserved sea urchin embryos (Paracentotus lividus) and provided a comparison to the already standardized sea urchin embryo-larval bioassay, using selected (organic and inorganic) pollutants and sediment elutriates from 4 different locations from Ria de Vigo harbour (Galicia, NW Iberian Peninsula). A cryopreservation protocol was designed in order to enable the successful cryopreservation and cryobanking of gametes and embryos to be used for marine quality assessment and ensure the accessibility to high quality reproductive material all year round, as an option to conditioning adults for out of season reproduction. The calculated EC50 using the cryopreserved blastula was 53.7 μg L(-1) for copper, 81.0 μg L(-1) for lead, 300.6 μg L(-1) for BP-3 and 300.6 μg L(-1) for 4-MBC. The sensitivity of the classic sea urchin embryo-larval bioassay was compared with the bioassay conducted with cryopreserved blastula. The results showed that the use of cryopreserved blastula bioassay allows detecting lower concentrations of pollutants in comparison with the classic bioassay. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Comparison of five in vitro bioassays to measure estrogenic activity in environmental waters.

    PubMed

    Leusch, Frederic D L; de Jager, Christiaan; Levi, Yves; Lim, Richard; Puijker, Leo; Sacher, Frank; Tremblay, Louis A; Wilson, Vickie S; Chapman, Heather F

    2010-05-15

    Bioassays are well established in the pharmaceutical industry and single compound analysis, but there is still uncertainty about their usefulness in environmental monitoring. We compared the responses of five bioassays designed to measure estrogenic activity (the yeast estrogen screen, ER-CALUX, MELN, T47D-KBluc, and E-SCREEN assays) and chemical analysis on extracts from four different water sources (groundwater, raw sewage, treated sewage, and river water). All five bioassays displayed similar trends and there was good agreement with analytical chemistry results. The data from the ER-CALUX and E-SCREEN bioassays were robust and predictable, and well-correlated with predictions from chemical analysis. The T47D-KBluc appeared likewise promising, but with a more limited sample size it was less compelling. The YES assay was less sensitive than the other assays by an order of magnitude, which resulted in a larger number of nondetects. The MELN assay was less predictable, although the possibility that this was due to laboratory-specific difficulties cannot be discounted. With standardized bioassay data analysis and consistency of operating protocols, bioanalytical tools are a promising advance in the development of a tiered approach to environmental water quality monitoring.

  11. Assessing the ecological risk of soil irrigated with wastewater using in vitro cell bioassays.

    PubMed

    Yu, Guo; Xiao, Ruiyang; Wang, Donghong; Zhou, Jun; Wang, Zijian

    2008-12-01

    In the most recent research work, the accumulation of toxicants in soil was always assessed through concentration level of the target contaminants. However, assessments based on chemical analysis were limited in numbers and in their unpredictable bioavailability. An alternative assessment could be based on toxicity assessment. It means that a screening bioassay is a necessary tool for identifying and defining contaminants at the sites, which should warrant further attention. In the present study, three in vitro cell bioassays, including the SOS/umu bioassay for genotoxic effects, human estrogen receptor recombinant yeast bioassay for estrogenic effects, and ethoxyresorfin O-deethylase (EROD) with H4IIE rat hepatoma cells bioassay for Ah-receptor agonistic effects, were used for the evaluation of the accumulation of toxicants in soils irrigated with wastewater in the suburb of Beijing, China. The results indicated that there were significant increases of genotoxic, estrogenic, and Ah-receptor agonistic effects in soils irrigated with wastewater, as compared with soils irrigated with groundwater. There was the decreased effect gradient following the increase of the distances from the inlet of the wastewater. It was concluded that wastewater irrigation could cause accumulation of genotoxic, estrogenic, and Ah-receptor agonistic chemicals in soil.

  12. Sensitivity assessment of sea lice to chemotherapeutants: Current bioassays and best practices.

    PubMed

    Marín, S L; Mancilla, J; Hausdorf, M A; Bouchard, D; Tudor, M S; Kane, F

    2017-12-18

    Traditional bioassays are still necessary to test sensitivity of sea lice species to chemotherapeutants, but the methodology applied by the different scientists has varied over time in respect to that proposed in "Sea lice resistance to chemotherapeutants: A handbook in resistance management" (2006). These divergences motivated the organization of a workshop during the Sea Lice 2016 conference "Standardization of traditional bioassay process by sharing best practices." There was an agreement by the attendants to update the handbook. The objective of this article is to provide a baseline analysis of the methodology for traditional bioassays and to identify procedures that need to be addressed to standardize the protocol. The methodology was divided into the following steps: bioassay design; material and equipment; sea lice collection, transportation and laboratory reception; preparation of dilution; parasite exposure; response evaluation; data analysis; and reporting. Information from the presentations of the workshop, and also from other studies, allowed for the identification of procedures inside a given step that need to be standardized as they were reported to be performed differently by the different working groups. Bioassay design and response evaluation were the targeted steps where more procedures need to be analysed and agreed upon. © 2017 John Wiley & Sons Ltd.

  13. Environmental fate and non-target impact of glyphosate-based herbicide (Roundup) in a subtropical wetland.

    PubMed

    Tsui, M T K; Chu, L M

    2008-03-01

    Mai Po Nature Reserve (Hong Kong) is an internationally important wetland for waterbirds. Roundup, a formulation based on glyphosate, has been used to control the widespread weeds within the reserve for many years but the fate and non-target impact of the herbicide is unknown. To fill this knowledge gap, we applied Roundup by hand-held sprayer to an estuarine and a freshwater pond in the dry season of year 2002. The surface water and sediment were sampled routinely for glyphosate concentrations following one month of application. In situ bioassays using local edible fish species were performed along with the herbicide application. Up to 52% of glyphosate in the surface water was transported to the unapplied regions by wind-driven current in the estuarine pond at 1 DPT (day post treatment). For both ponds, glyphosate concentrations in the water decreased rapidly after 1-3 DPT, but then decreased gradually over time. Both physical adsorption to the bottom sediments and microbial degradation are thought to contribute to these decreases. Interestingly, the persistence of glyphosate in the freshwater pond was longer than in the estuarine system, which is likely due to the considerably higher concentrations of chelating metals (i.e. Cu and Fe) present in the sediment (4.5 and 11-fold higher, respectively) which potentially reduced the bioavailability of glyphosate to the microbial decomposers. Lastly, fishes used in the in situ bioassays (both in applied and unapplied areas) showed similar survival rates, indicating that the use of Roundup at the provided application rate posed no serious hazard.

  14. Integrating Communication Skills into Functional Routines & Activities.

    ERIC Educational Resources Information Center

    Stremel, Kathleen

    This training module on integrating communication skills into functional routines and activities is from the Mississippi Early Education Program for Children with Multiple Disabilities, a program designed to train Individuals with Disabilities Education Act Part H service coordinators and service providers to use family centered strategies. The…

  15. THE OECD PROGRAM TO VALIDATE THE RAT HERSHBERGER BIOASSAY TO SCREEN COMPOUNDS FOR IN VIVO ANDROGEN AND ANTIANDROGEN RESPONSES. PHASE 1: USE OF A POTENT AGONIST AND A POTENT ANTAGONIST TO TEST THE STANDARDIZED PROTOCOL

    EPA Science Inventory

    The OECD has completed Phase-1 of the Hershberger validation intended to identify in vivo activity of

    suspected androgens and antiandrogens. 17 laboratories from 7 countries participated in Phase-1, and results

    were collated and evaluated by the OECD with the suppor...

  16. Determination of 235U/238U Ratio on Urine by ICP-MS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Collins, L; Gobaleza, A; Langston, R

    2011-10-19

    LLNL Internal Dosimetry Program - The new procedure satisfies the requirement to determine {sup 235}U/{sup 238}U ratio in bioassay urine samples. MDA - The L{sub C} and MDA{sub 95} for {sup 235}U are well below the required detection limit of 0.00035 {mu}g/L. Turn around time - Analysis of 10 samples plus 2 QCs can be completed in one work day (8 hours).

  17. Examining the cost of delivering routine immunization in Honduras.

    PubMed

    Janusz, Cara Bess; Castañeda-Orjuela, Carlos; Molina Aguilera, Ida Berenice; Felix Garcia, Ana Gabriela; Mendoza, Lourdes; Díaz, Iris Yolanda; Resch, Stephen C

    2015-05-07

    Many countries have introduced new vaccines and expanded their immunization programs to protect additional risk groups, thus raising the cost of routine immunization delivery. Honduras recently adopted two new vaccines, and the country continues to broaden the reach of its program to adolescents and adults. In this article, we estimate and examine the economic cost of the Honduran routine immunization program for the year 2011. The data were gathered from a probability sample of 71 health facilities delivering routine immunization, as well as 8 regional and 1 central office of the national immunization program. Data were collected on vaccinations delivered, staff time dedicated to the program, cold chain equipment and upkeep, vehicle use, infrastructure, and other recurrent and capital costs at each health facility and administrative office. Annualized economic costs were estimated from a modified societal perspective and reported in 2011 US dollars. With the addition of rotavirus and pneumococcal conjugate vaccines, the total cost for routine immunization delivery in Honduras for 2011 was US$ 32.5 million. Vaccines and related supplies accounted for 23% of the costs. Labor, cold chain, and vehicles represented 54%, 4%, and 1%, respectively. At the facility level, the non-vaccine system costs per dose ranged widely, from US$ 25.55 in facilities delivering fewer than 500 doses per year to US$ 2.84 in facilities with volume exceeding 10,000 doses per year. Cost per dose was higher in rural facilities despite somewhat lower wage rates for health workers in these settings; this appears to be driven by lower demand for services per health worker in sparsely populated areas, rather than increased cost of outreach. These more-precise estimates of the operational costs to deliver routine immunizations provide program managers with important information for mobilizing resources to help sustain the program and for improving annual planning and budgeting as well as longer-term resource allocation decisions. Copyright © 2015. Published by Elsevier Ltd.

  18. Bioanalytical tools for the evaluation of organic micropollutants during sewage treatment, water recycling and drinking water generation.

    PubMed

    Macova, Miroslava; Toze, Simon; Hodgers, Leonie; Mueller, Jochen F; Bartkow, Michael; Escher, Beate I

    2011-08-01

    A bioanalytical test battery was used for monitoring organic micropollutants across an indirect potable reuse scheme testing sites across the complete water cycle from sewage to drinking water to assess the efficacy of different treatment barriers. The indirect potable reuse scheme consists of seven treatment barriers: (1) source control, (2) wastewater treatment plant, (3) microfiltration, (4) reverse osmosis, (5) advanced oxidation, (6) natural environment in a reservoir and (7) drinking water treatment plant. Bioanalytical results provide complementary information to chemical analysis on the sum of micropollutants acting together in mixtures. Six endpoints targeting the groups of chemicals with modes of toxic action of particular relevance for human and environmental health were included in the evaluation: genotoxicity, estrogenicity (endocrine disruption), neurotoxicity, phytotoxicity, dioxin-like activity and non-specific cell toxicity. The toxicity of water samples was expressed as toxic equivalent concentrations (TEQ), a measure that translates the effect of the mixtures of unknown and potentially unidentified chemicals in a water sample to the effect that a known reference compound would cause. For each bioassay a different representative reference compound was selected. In this study, the TEQ concept was applied for the first time to the umuC test indicative of genotoxicity using 4-nitroquinoline as the reference compound for direct genotoxicity and benzo[a]pyrene for genotoxicity after metabolic activation. The TEQ were observed to decrease across the seven treatment barriers in all six selected bioassays. Each bioassay showed a differentiated picture representative for a different group of chemicals and their mixture effect. The TEQ of the samples across the seven barriers were in the same order of magnitude as seen during previous individual studies in wastewater and advanced water treatment plants and reservoirs. For the first time a benchmarking was performed that allows direct comparison of different treatment technologies and covers several orders of magnitude of TEQ from highly contaminated sewage to drinking water with TEQ close or below the limit of detection. Detection limits of the bioassays were decreased in comparison to earlier studies by optimizing sample preparation and test protocols, and were comparable to or lower than the quantification limits of the routine chemical analysis, which allowed monitoring of the presence and removal of micropollutants post Barrier 2 and in drinking water. The results obtained by bioanalytical tools were reproducible, robust and consistent with previous studies assessing the effectiveness of the wastewater and advanced water treatment plants. The results of this study indicate that bioanalytical results expressed as TEQ are useful to assess removal efficiency of micropollutants throughout all treatment steps of water recycling. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Evaluating Ethanol-based Sample Preservation to Facilitate Use of DNA Barcoding in Routine Freshwater Biomonitoring Programs Using Benthic Macroinvertebrates

    EPA Science Inventory

    Molecular methods, such as DNA barcoding, have the potential in enhance biomonitoring programs worldwide. Altering routinely used sample preservation methods to protect DNA from degradation may pose a potential impediment to application of DNA barcoding and metagenomics for biom...

  20. Environmental Quality Research Fish and Aufwuchs Bioassay

    DTIC Science & Technology

    1981-01-01

    reproductive success at WSF of shale JP-8 concentrations of 0. 51 ± 0. 30 mg/V. Results of continuous-flow bioassays of the WSF of hydrocarbon fuels to...42 Reproduction .................... ....................... 42 SALINE WATER BIOASSAYS OF HYDROCARBON FUELS ...... . . 47...and development and reproductive ability. Studies on JP-4, JP-8, and shale JP-8 have been conducted in saline water from San Francisco Bay at the

  1. Enablers of and barriers to abortion training.

    PubMed

    Guiahi, Maryam; Lim, Sahnah; Westover, Corey; Gold, Marji; Westhoff, Carolyn L

    2013-06-01

    Since the legalization of abortion services in the United States, provision of abortions has remained a controversial issue of high political interest. Routine abortion training is not offered at all obstetrics and gynecology (Ob-Gyn) training programs, despite a specific training requirement by the Accreditation Council for Graduate Medical Education. Previous studies that described Ob-Gyn programs with routine abortion training either examined associations by using national surveys of program directors or described the experience of a single program. We set out to identify enablers of and barriers to Ob-Gyn abortion training in the context of a New York City political initiative, in order to better understand how to improve abortion training at other sites. We conducted in-depth qualitative interviews with 22 stakeholders from 7 New York City public hospitals and focus group interviews with 62 current residents at 6 sites. Enablers of abortion training included program location, high-capacity services, faculty commitment to abortion training, external programmatic support, and resident interest. Barriers to abortion training included lack of leadership continuity, leadership conflict, lack of second-trimester abortion services, difficulty obtaining mifepristone, optional rather than routine training, and antiabortion values of hospital personnel. Supportive leadership, faculty commitment, and external programmatic support appear to be key elements for establishing routine abortion training at Ob-Gyn residency training programs.

  2. The medical story. [Skylab program

    NASA Technical Reports Server (NTRS)

    Johnston, R. S.; Dietlein, L. F.; Michel, E. L.

    1974-01-01

    An overview of the Skylab medical program is given. All medical subsystems provided in the orbital workshop functioned satisfactorily. Major systems included the food system, the waste management system, and provisions per personal hygiene. A series of lockers in the wardroom was used to stow the inflight medical support system. Cardiovascular counter pressure garments were launched in the orbital workshop for all three crews. Life services experiments were carried out. Two experiments were conducted in the Skylab missions to study the performance of the cardiovascular system during weightless flight and return to earth and the one g environment. A series of experiments was conducted to study mineral balance and the bioassay of body fluids.

  3. Drug-nutrient interactions and their implications for safety evaluations.

    PubMed

    Conner, M W; Newberne, P M

    1984-06-01

    In order to assess the relevance of the drug-nutrient interactions described in this chapter to routine toxicologic studies, the range of nutrient concentrations within which these interactions may occur must be compared to the range of nutrient concentrations found in routinely used rodent diets. While obviously deficient levels of some nutrients were supplied to demonstrate some of the interactions, others occur when the nutrients are present in adequate or excess levels, such as might be found in commercially available diets. These diets are known to vary from batch to batch in nutrient content. A lifetime toxicity/carcinogenicity bioassay using rodents may last longer than 2 years, during which time several batches of diet will be used. The variation in diet composition, coupled with inadequate diet description, makes nutrient-toxin interactions not only possible, but difficult to recognize. These considerations raise the practical and philosophical question as to what type of diet is most appropriate for rodents used for safety evaluation of drugs and chemicals. Is it appropriate to use diets that vary unpredictably in nutrient content, that infer a degree of protection against chemical carcinogenesis and which supply some nutrients such as protein in great excess of dietary needs? Is the increase in sensitivity to chemical carcinogens of animals fed purified diets desirable or does this increased sensitivity of the bioassay exceed that required to assess the risk of human exposure? In other words, is the use of purified diets likely to increase the number of false positive results? Proper interpretation and extrapolation of safety evaluation studies requires adequate description of the test system. Given the profound influence of diet on the response to some toxins, the composition of the diet should, ideally, be defined with the same rigor as are the test compound and the strain, age, sex, and housing conditions of the animals. It is likely, however, that natural ingredients diets will continue to be the diets of choice in safety evaluation studies. This is largely due to economic reasons. It is possible, however, to use these diets with greater confidence if open-formula diets are used and the concentration of each nutrient is reported. Consideration should also be given to preparing diets for use in adult and aging rodents, diets in which protein content is reduced.(ABSTRACT TRUNCATED AT 400 WORDS)

  4. A Comparative Analysis of Coprologic Diagnostic Methods for Detection of Toxoplama gondii in Cats

    PubMed Central

    Salant, Harold; Spira, Dan T.; Hamburger, Joseph

    2010-01-01

    The relative role of transmission of Toxoplasma gondii infection from cats to humans appears to have recently increased in certain areas. Large-scale screening of oocyst shedding in cats cannot rely on microscopy because oocyst identification lacks sensitivity and specificity, or on bioassays, which require test animals and weeks before examination. We compared a sensitive and species-specific coprologic–polymerase chain reaction (copro-PCR) for detection of T. gondii infected cats with microscopy and a bioassay. In experimentally infected cats followed over time, microscopy was positive occasionally, and positive copro-PCR and bioassay results were obtained continuously from days 2 to 24 post-infection. The copro-PCR is at least as sensitive and specific as the bioassay and is capable of detecting infective oocysts during cat infection. Therefore, this procedure can be used as the new gold standard for determining potential cat infectivity. Its technologic advantages over the bioassay make it superior for large-scale screening of cats. PMID:20439968

  5. Bioassay of naturally occurring allelochemicals for phytotoxicity.

    PubMed

    Leather, G R; Einhellig, F A

    1988-10-01

    The bioassay has been one of the most widely used tests to demonstrate allelopathic activity. Often, claims that a particular plant species inhibits the growth of another are based entirely on the seed germination response to solvent extracts of the suspected allelopathic plant; few of these tests are of value in demonstrating allelopathy under natural conditions. The veracity of the bioassay for evaluating naturally occurring compounds for phytotoxicity depends upon the physiological and biochemical response capacity of the bioassay organism and the mechanism(s) of action of the allelochemicals. The possibility that more than one allelochemical, acting in concert at very low concentrations, may be responsible for an observed allelopathic effect makes it imperative that bioassays be extremely sensitive to chemical growth perturbation agents. Among the many measures of phytotoxicity of allelochemicals, the inhibition (or stimulation) of seed germination, radicle elongation, and/or seedling growth have been the parameters of choice for most investigations. Few of these assays have been selected with the view towards the possible mechanism of the allelopathic effect.

  6. Comparison of solid-phase bioassays and ecoscores to evaluate the toxicity of contaminated soils.

    PubMed

    Lors, Christine; Ponge, Jean-François; Martínez Aldaya, Maite; Damidot, Denis

    2010-08-01

    Five bioassays (inhibition of lettuce germination and growth, earthworm mortality, inhibition of springtail population growth, avoidance by springtails) were compared, using four coke factory soils contaminated by PAHs and trace elements, before and after biotreatment. For each bioassay, several endpoints were combined in an 'ecoscore', a measure of test sensitivity. Ecoscores pooled over all tested bioassays revealed that most organisms were highly sensitive to the concentration of 3-ring PAHs. When four soils were combined, behavioural tests using the springtail Folsomia candida showed higher ecoscores, i.e. they were most sensitive to soil contamination. However, despite overall higher sensitivity of behavioural tests, which could be used for cheap and rapid assessment of soil toxicity, especially at low levels of contamination, some test endpoints were more sensitive than others, and this may differ from a soil to another, pointing to the need for a battery of bioassays when more itemized results are expected. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Comparative performances of eggs and embryos of sea urchin (Paracentrotus lividus) in toxicity bioassays used for assessment of marine sediment quality.

    PubMed

    Khosrovyan, A; Rodríguez-Romero, A; Salamanca, M J; Del Valls, T A; Riba, I; Serrano, F

    2013-05-15

    The potential toxicity of sediments from various ports was assessed by means of two different liquid-phase toxicity bioassays (acute and chronic) with embryos and eggs of sea urchin Paracentrotus lividus. Performances of embryos and eggs of P. lividus in these bioassays were compared for their interchangeable applicability in integrated sediment quality assessment. The obtained endpoints (percentages of normally developed plutei and fertilized eggs) were linked to physical and chemical properties of sediments and demonstrated dependence on sediment contamination. The endpoints in the two bioassays were strongly correlated and generally exhibited similar tendency throughout the samples. Therein, embryos demonstrated higher sensitivity to elutriate exposure, compared to eggs. It was concluded that these tests could be used interchangeably for testing toxicity of marine sediments. Preferential use of any of the bioassays can be determined by the discriminatory capacity of the test or vulnerability consideration of the test subject to the surrounding conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. A rapid bioassay for detecting saxitoxins using a Daphnia acute toxicity test.

    PubMed

    Ferrão-Filho, Aloysio da S; Soares, Maria Carolina S; de Magalhães, Valéria Freitas; Azevedo, Sandra M F O

    2010-06-01

    Bioassays using Daphnia pulex and Moina micrura were designed to detect cyanobacterial neurotoxins in raw water samples. Phytoplankton and cyanotoxins from seston were analyzed during 15 months in a eutrophic reservoir. Effective time to immobilize 50% of the exposed individuals (ET50) was adopted as the endpoint. Paralysis of swimming movements was observed between approximately 0.5-3 h of exposure to lake water containing toxic cyanobacteria, followed by an almost complete recovery of the swimming activity within 24 h after being placed in control water. The same effects were observed in bioassays with a saxitoxin-producer strain of Cylindrospermopsis raciborskii isolated from the reservoir. Regression analysis showed significant relationships between ET50 vs. cell density, biomass and saxitoxins content, suggesting that the paralysis of Daphnia in lake water samples was caused by saxitoxins found in C. raciborskii. Daphnia bioassay was found to be a sensitive method for detecting fast-acting neurotoxins in natural samples, with important advantages over mouse bioassays. Copyright 2010 Elsevier Ltd. All rights reserved.

  9. In situ bioassays with Chironomus riparius larvae to biomonitor metal pollution in rivers and to evaluate the efficiency of restoration measures in mine areas.

    PubMed

    Faria, Mafalda S; Lopes, Ricardo J; Malcato, João; Nogueira, António J A; Soares, Amadeu M V M

    2008-01-01

    In this study we evaluate the ability of an in situ bioassay with Chironomus riparius larvae, using larval development and growth as endpoints, to biomonitor water quality and to assess the biological recovery of metal contaminated freshwater ecosystems of mine areas that are subject of restoration measures. The bioassay was carried out in streams located near an abandoned goldmine in North Portugal, throughout an environmental rehabilitation of the mine (2002-2004). During this period, a decrease in the inhibition of larval growth in the metal contaminated stream was observed. The bioassay was also performed in streams located near an active tungsten mine in Central Portugal. Larval growth and development were highly inhibited in the stream that receives acid drainage from the tungsten mine and treated water from the AMD treatment station. The results indicate that the bioassay can be used to evaluate the efficiency of environmental restoration measures in mining areas.

  10. Real-time PCR for the early detection and quantification of Coxiella burnetii as an alternative to the murine bioassay.

    PubMed

    Howe, Gerald B; Loveless, Bonnie M; Norwood, David; Craw, Philip; Waag, David; England, Marilyn; Lowe, John R; Courtney, Bernard C; Pitt, M Louise; Kulesh, David A

    2009-01-01

    Real-time PCR was used to analyze archived blood from non-human primates (NHP) and fluid samples originating from a well-controlled Q fever vaccine efficacy trial. The PCR targets were the IS1111 element and the com1 gene of Coxiella burnetii. Data from that previous study were used to evaluate real-time PCR as an alternative to the use of sero-conversion by mouse bioassay for both quantification and early detection of C. burnetii bacteria. Real-time PCR and the mouse bioassay exhibited no statistical difference in quantifying the number of microorganisms delivered in the aerosol challenge dose. The presence of C. burnetii in peripheral blood of non-human primates was detected by real-time PCR as early after exposure as the mouse bioassay with results available within hours instead of weeks. This study demonstrates that real-time PCR has the ability to replace the mouse bioassay to measure dosage and monitor infection of C. burnetii in a non-human primate model.

  11. Use of bioassays to assess hazard of food contact material extracts: State of the art.

    PubMed

    Severin, Isabelle; Souton, Emilie; Dahbi, Laurence; Chagnon, Marie Christine

    2017-07-01

    This review focuses on the use of in vitro bioassays for the hazard assessment of food contact materials (FCM) as a relevant strategy, in complement to analytical methods. FCM may transfer constituents to foods, not always detected by analytical chemistry, resulting in low but measurable human exposures. Testing FCM extracts with bioassays represents the biological response of a combination of substances, able to be released from the finished materials. Furthermore, this approach is particularly useful regarding the current risk assessment challenges with unpredicted/unidentified non-intentionally added substances (NIAS) that can be leached from the FCM in the food. Bioassays applied to assess hazard of different FCM types are described for, to date, the toxicological endpoints able to be expressed at low levels; cytotoxicity, genotoxicity and endocrine disruption potential. The bioassay strengths and relative key points needed to correctly use and improve the performance of bioassays for an additional FCM risk assessment is developed. This review compiles studies showing that combining both chemical and toxicological analyses presents a very promising and pragmatic tool for identifying new undesirable NIAS (not predicted) which can represent a great part of the migrating substances and/or "cocktail effect". Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Design and Proof-of-Concept Use of a Circular PMMA Platform with 16-Well Sample Capacity for Microwave-Accelerated Bioassays.

    PubMed

    Mohammed, Muzaffer; Aslan, Kadir

    2013-01-01

    We demonstrate the design and the proof-of-concept use of a new, circular poly(methyl methacrylate)-based bioassay platform (PMMA platform), which affords for the rapid processing of 16 samples at once. The circular PMMA platform (5 cm in diameter) was coated with a silver nanoparticle film to accelerate the bioassay steps by microwave heating. A model colorimetric bioassay for biotinylated albumin (using streptavidin-labeled horse radish peroxidase) was performed on the PMMA platform coated with and without silver nanoparticles (a control experiment), and at room temperature and using microwave heating. It was shown that the simulated temperature profile of the PMMA platform during microwave heating were comparable to the real-time temperature profile during actual microwave heating of the constructed PMMA platform in a commercial microwave oven. The model colorimetric bioassay for biotinylated albumin was successfully completed in ~2 min (total assay time) using microwave heating, as compared to 90 min at room temperature (total assay time), which indicates a ~45-fold decrease in assay time. Our PMMA platform design afforded for significant reduction in non-specific interactions and low background signal as compared to non-silvered PMMA surfaces when employed in a microwave-accelerated bioassay carried out in a conventional microwave cavity.

  13. A Novel in vitro Bioassay to Explore the Repellent Effects of Compounds Against Mosquito Aedes aegypti (Diptera: Culicidae).

    PubMed

    Rehman, Junaid U; Tabanca, Nurhayat; Khan, Ikhlas A

    2016-01-01

    Mosquitoes are vectors for many pathogens resulting in many deaths of humans. Repellents play an important role in reducing mosquito bites and the spread of mosquito-borne diseases. Currently, Klun & Debboun (K & D) and human-arm-based bioassay systems are used to identify repellent properties of compounds, extracts, and essential oils. Risks involved with human-arm-based systems are allergic reactions and limited replicates. We are reporting an in vitro bioassay method “NCNPR repellent bioassay (NCNPR-RB)” that can closely simulate the results of the cloth patch bioassay system used to determine repellency against mosquitoes. The NCNPRRB method uses heat to attract mosquito and edible collagen sheets as an alternate to human skin. Multiple plant compounds with documented repellency were tested. DEET (N,N-diethyl-3-methylbenzamide) was used as a positive control. Treatments were prepared in EtOH and applied in dosages ranging from 0.011–1.5mg/cm2 to a 20-cm2 collagen sheet. The number of mosquitoes commencing to bite per probe was recorded visually for 1 min. The minimum effective dosage (mg/cm2) of compounds: DEET (0.021), carvacrol (0.011), thymol (0.013), undecanoic acid (0.023), thymol methyl ether (0.269), and 2-nonanone (>0.375 mg/cm2) determined in NCNPRRB were similar to those reported in literature using a cloth patch bioassay system. The NCNPR-RB can be used to screen compounds with reasonable reproducibility of the data at a faster rate than the cloth patch bioassay, which involves the use of human subjects.

  14. “Kicking the Tires” of the energy balance routine within the CROPGRO crop growth models of DSSAT

    USDA-ARS?s Scientific Manuscript database

    Two decades ago a routine called ETPHOT was written to compute evaporation, transpiration, and photosynthesis in the CROPGRO crop simulation programs for grain legumes such as soybean. These programs are part of the DSSAT (Decision Support System of Agrotechnology Transfer), which has been widely us...

  15. Embedding Intervention Targets into Caregiving Routines and Other Activities of the Families Choice.

    ERIC Educational Resources Information Center

    Hollingshead, Lorie; Harris, Kristy; Stremel, Kathleen

    This training module on embedding intervention targets into caregiving routines and other activities of the families' choice is from the Mississippi Early Education Program for Children with Multiple Disabilities, a program designed to train Individuals with Disabilities Education Act Part H service coordinators and service providers to use family…

  16. NTP Carcinogenesis Bioassay of Diallyl Phthalate (CAS No. 131-17-9) in B6C3F1 Mice (Gavage Study).

    PubMed

    1983-04-01

    Diallyl phthalate is a widely used crosslinking agent for unsaturated polyesters. Diallyl phthalate or diallyl phthalate polyester blends are used primarily as plasticizers and carriers for adding catalysts and pigments to polyesters and in molding, electrical parts, laminating compounds, and impregnation of metal castings. Rubber compounds, epoxy formulations, and polyurethane foams may also contain diallyl phthalate. Annual production of diallyl phthalate in the United States exceeds 5,000 pounds; precise figures are not available. A NTP Carcinogenesis bioassay of diallyl phthalate (99% pure) was conducted by administering 0 (vehicle control), 150, or 300 mg/kg diallyl phthalate in corn oil by gavage, 5 days per week for 103 weeks, to groups of 50 male and 50 female B6C3F1 mice. Survival rates and mean body weights of dosed mice were not different from those of the controls, and pathological lesions unrelated to proliferative changes were not observed. Therefore, a maximally tolerated dose for the purposes of carcinogenicity testing may not have been achieved. The incidences of lymphoma and either lymphoma or leukemia in dosed male mice were no significantly greater than those in the controls according to pairwise comparisons (P=0.051 to P=0.096), but the trend tests were statistically significant by either life table or incidental tumor analysis (P=0.031 to P=0.045). The incidence of lymphomas in the high-dose male mice was 12/50 (24%) in comparison with 6/50 (12%) in the controls. Recent historical incidences at the performing laboratory and in the NTP Bioassay Program were 18/120 (15%) and 71/661 (11%), respectively. Since the incidence of high-dose male mice with leukemia was not significantly greater than that of concurrent or historical controls at the performing laboratory by pairwise comparisons, this marginal increase was considered only to be equivocally related to diallyl phthalate administration. Increased incidences of squamous cell papillomas, hyperplasia, and inflammatory lesions of the forestomach were observed in diallyl phthalate-dosed mice of both sexes in a dose-related manner. Papillomas of the forestomach were observed in 0%, 2%, and 4% of the control, low-dose, and high-dose mice of both sexes. The recent historical incidence of this tumor in gavage control mice from both the performing laboratory and other laboratories within the Bioassay Program was less than 1%. Forestomach hyperplasia was diagnosed in 0%, 15%, and 18%, and in 8%, 2%, and 29% of the control, low-dose, and high-dose male and female mice, respectively; chronic inflammation of the forestomach was diagnosed in 0%, 9%, and 16% and in 4%, 2%, and 18% of the control, low-dose, and high-dose male and female mice, respectively. Because of the numerical elevation of the forestomach papillomas in the high-dose mice of both sexes, the concomitant observation of dose related forestomach hyperplasia, and the rarity of this tumor in corn oil (gavage) control B6C3F1 mice, the development of squamous cell papillomas of the forestomach may have been related to diallyl phthalate administration. Under the conditions of this bioassay, the development of chronic inflammation and hyperplasia of the forestomach in both male and female B6C3F1 mice was considered to be related to the administration of diallyl phthalate. The development of squamous cell papillomas of the forestomach may also have been related to chemical administration, but the available data are insufficient to indicate a clear cause and effect relationship. An increase in the incidence of male mice with lymphomas was observed, but this increase was considered only to be equivocally related to diallyl phthalate administration. The results of this bioassay, therefore, do not indicate that diallyl phthalate is carcinogenic in B6C3F1 mice, although a maximum tolerated dose may not have been achieved. A carcinogenicity study by the National Toxicology Program of diallyl phthalate in male and female Fisher 344/N rats, employing daily gavage doses of 0 (vehicle control), 50, or 100 mg/kg boicology Program of diallyl phthalate in male and female Fisher 344/N rats, employing daily gavage doses of 0 (vehicle control), 50, or 100 mg/kg body weight is currently being evaluated. Levels of Evidence of Carcinogenicity: Male Mice: Equivocal Female Mice: Equivocal

  17. Solubility testing of actinides on breathing-zone and area air samples

    NASA Astrophysics Data System (ADS)

    Metzger, Robert Lawrence

    The solubility of inhaled radionuclides in the human lung is an important characteristic of the compounds needed to perform internal dosimetry assessments for exposed workers. A solubility testing method for uranium and several common actinides has been developed with sufficient sensitivity to allow profiles to be determined from routine breathing zone and area air samples in the workplace. Air samples are covered with a clean filter to form a filter-sample-filter sandwich which is immersed in an extracellular lung serum simulant solution. The sample is moved to a fresh beaker of the lung fluid simulant each day for one week, and then weekly until the end of the 28 day test period. The soak solutions are wet ashed with nitric acid and hydrogen peroxide to destroy the organic components of the lung simulant solution prior to extraction of the nuclides of interest directly into an extractive scintillator for subsequent counting on a Photon-Electron Rejecting Alpha Liquid Scintillation (PERALSsp°ler ) spectrometer. Solvent extraction methods utilizing the extractive scintillators have been developed for the isotopes of uranium, plutonium, and curium. The procedures normally produce an isotopic recovery greater than 95% and have been used to develop solubility profiles from air samples with 40 pCi or less of Usb3Osb8. This makes it possible to characterize solubility profiles in every section of operating facilities where airborne nuclides are found using common breathing zone air samples. The new method was evaluated by analyzing uranium compounds from two uranium mills whose product had been previously analyzed by in vitro solubility testing in the laboratory and in vivo solubility testing in rodents. The new technique compared well with the in vivo rodent solubility profiles. The method was then used to evaluate the solubility profiles in all process sections of an operating in situ uranium plant using breathing zone and area air samples collected during routine plant operations. The solubility profiles developed from this work showed excellent agreement with the results of the worker urine bioassay program at the plant and identified a significant error in existing internal dose assessments at this facility.

  18. User's manual for MMLE3, a general FORTRAN program for maximum likelihood parameter estimation

    NASA Technical Reports Server (NTRS)

    Maine, R. E.; Iliff, K. W.

    1980-01-01

    A user's manual for the FORTRAN IV computer program MMLE3 is described. It is a maximum likelihood parameter estimation program capable of handling general bilinear dynamic equations of arbitrary order with measurement noise and/or state noise (process noise). The theory and use of the program is described. The basic MMLE3 program is quite general and, therefore, applicable to a wide variety of problems. The basic program can interact with a set of user written problem specific routines to simplify the use of the program on specific systems. A set of user routines for the aircraft stability and control derivative estimation problem is provided with the program.

  19. Nonlinear wave choked inlets

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The quasi-one dimensional flow program was modified in two ways. The Runge-Kutta subroutine was replaced with a subroutine which used a modified divided difference form of the Adams Pece method and the matrix inversion routine was replaced with a pseudo inverse routine. Calculations were run using both the original and modified programs. Comparison of the calculations showed that the original Runge-Kutta routine could not detect singularity near the throat and was integrating across it. The modified version was able to detect the singularity and therefore gave more valid calculations.

  20. Improvements in Routing for Packet-Switched Networks

    DTIC Science & Technology

    1975-02-18

    PROGRAM FOR COMPUTER SIMULATION . . 90 B.l Flow Diagram of Adaptive Routine 90 B.2 Progiam ARPSIM 93 B.3 Explanation of Variables...equa. 90 APPENDIX B ADAPTIVE ROUTING PROGRAM FOR COMPUTER SIMULA HON The computer simulation for adaptive routing was initially run on a DDP-24 small...TRANSMIT OVER AVAILABLE LINKS MESSAGES IN QUEUE COMPUTE Ni NUMBER OF ARRIVALS AT EACH NODE i AT TIME T Fig. Bla - Flow Diagram of Program Routine 92

  1. Nanomaterial-Based Electrochemical Biosensors and Bioassays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Guodong; Mao, Xun; Gurung, Anant

    2010-08-31

    This book chapter summarizes the recent advance in nanomaterials for electrochemical biosensors and bioassays. Biofunctionalization of nanomaterials for biosensors fabrication and their biomedical applications are discussed.

  2. Economics of an adolescent meningococcal conjugate vaccination catch-up campaign in the United States.

    PubMed

    Ortega-Sanchez, Ismael R; Meltzer, Martin I; Shepard, Colin; Zell, Elizabeth; Messonnier, Mark L; Bilukha, Oleg; Zhang, Xinzhi; Stephens, David S; Messonnier, Nancy E

    2008-01-01

    In June 2005, the Advisory Committee on Immunization Practices recommended the newly licensed quadrivalent meningococcal conjugate vaccine for routine use among all US children aged 11 years. A 1-time catch-up vaccination campaign for children and adolescents aged 11-17 years, followed by routine annual immunization of each child aged 11 years, could generate immediate herd immunity benefits. The objective of our study was to analyze the cost-effectiveness of a catch-up vaccination campaign with quadrivalent meningococcal conjugate vaccine for children and adolescents aged 11-17 years. We built a probabilistic model of disease burden and economic impacts for a 10-year period with and without a program of adolescent catch-up meningococcal vaccination, followed by 9 years of routine immunization of children aged 11 years. We used US age- and serogroup-specific surveillance data on incidence and mortality. Assumptions related to the impact of herd immunity were drawn from experience with routine meningococcal vaccination in the United Kingdom. We estimated costs per case, deaths prevented, life-years saved, and quality-adjusted life-years saved. With herd immunity, the catch-up and routine vaccination program for adolescents would prevent 8251 cases of meningococcal disease in a 10-year period (a 48% decrease). Excluding program costs, this catch-up and routine vaccination program would save US$551 million in direct costs and $920 million in indirect costs, including costs associated with permanent disability and premature death. At $83 per vaccinee, the catch-up vaccination would cost society approximately $223,000 per case averted, approximately $2.6 million per death prevented, approximately $127,000 per life-year saved, and approximately $88,000 per quality-adjusted life-year saved. Targeting counties with a high incidence of disease decreased the cost per life-year saved by two-thirds. Although costly, catch-up and routine vaccination of adolescents can have a substantial impact on meningococcal disease burden. Because of herd immunity, catch-up and routine vaccination cost per life-year saved could be up to one-third less than that previously assessed for routine vaccination of children aged 11 years.

  3. Embedding Physical Activity and Nutrition in Early Care and Education Programs

    ERIC Educational Resources Information Center

    Deiner, Penny Low; Qiu, Wei

    2007-01-01

    The infant and toddler years provide a window of opportunity to establish healthy habits as part of daily routines and activities that prevent childhood obesity. Early care and education programs have the opportunity to make a significant impact on physical development when they promote healthy eating and physical activity in their daily routines.…

  4. Nonanalytic function generation routines for 16-bit microprocessors

    NASA Technical Reports Server (NTRS)

    Soeder, J. F.; Shaufl, M.

    1980-01-01

    Interpolation techniques for three types (univariate, bivariate, and map) of nonanalytic functions are described. These interpolation techniques are then implemented in scaled fraction arithmetic on a representative 16 bit microprocessor. A FORTRAN program is described that facilitates the scaling, documentation, and organization of data for use by these routines. Listings of all these programs are included in an appendix.

  5. Orbiter/payload contamination control assessment support

    NASA Technical Reports Server (NTRS)

    Rantanen, R. O.; Strange, D. A.; Hetrick, M. A.

    1978-01-01

    The development and integration of 16 payload bay liner filters into the existing shuttle/payload contamination evaluation (SPACE) computer program is discussed as well as an initial mission profile model. As part of the mission profile model, a thermal conversion program, a temperature cycling routine, a flexible plot routine and a mission simulation of orbital flight test 3 are presented.

  6. Baseline susceptibility of Planococcus ficus (Hemiptera: Pseudococcidae) from California to select insecticides.

    PubMed

    Prabhaker, Nilima; Gispert, Carmen; Castle, Steven J

    2012-08-01

    Between 2006 and 2008, 20 populations of Planococcus ficus (Signoret), from Coachella and San Joaquin Valleys of California were measured in the laboratory for susceptibility to buprofezin, chlorpyrifos, dimethoate, methomyl, and imidacloprid. Toxicity was assessed using a petri dish bioassay technique for contact insecticides and by a systemic uptake technique for imidacloprid. Mixed life stages were tested for susceptibility to all insecticides except for buprofezin, which was measured against early and late instars (first, second, and third). Dose-response regression lines from the mortality data established LC50 and LC99 values by both techniques. Responses of populations from the two geographical locations to all five insecticides varied, in some cases significantly. Variations in susceptibility to each insecticide among sample sites showed a sevenfold difference for buprofezin, 11-fold to chlorpyrifos, ninefold to dimethoate, 24-fold to methomyl, and 8.5-fold to imidacloprid. In spite of susceptibility differences between populations, baseline toxicity data revealed that all five insecticides were quite effective based on low LC50s. Chlorpyrifos was the most toxic compound to Planococcus ficus populations as shown by lowest LC50s. Buprofezin was toxic to all immature stages but was more potent to first instars. The highest LC99 estimated by probit analysis of the bioassay data of all 20 populations for each compound was selected as a candidate discriminating dose for use in future resistance monitoring efforts. Establishment of baseline data and development of resistance monitoring tools such as bioassay methods and discriminating doses are essential elements of a sustainable management program for Planococcus ficus.

  7. Acute Toxicity of Fresh and Aged Residues of Pesticides to the Parasitoid Tamarixia radiata and to the HLB-Bacteria Vector Diaphorina citri.

    PubMed

    Beloti, V H; Alves, G R; Moral, R A; Demétrio, C G B; Yamamoto, P T

    2018-06-01

    One method for controlling the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama, the vector of the putative causal agent of Huanglongbing, uses the parasitoid Tamarixia radiata (Waterston). However, the general intensive use of insecticides has reduced the numbers of this parasitoid. This study evaluated the effect of the residual action of 24 insecticides on T. radiata and also determined the differential toxicity of insecticides to D. citri and T. radiata, using three bioassays. In the first, when adults of the parasitoid were exposed to residues of the 24 insecticides, ten were considered short-life (class 1), six slightly persistent (class 2), five moderately persistent (class 3), and three insecticides were considered persistent (class 4), under the IOBC/WPRS classification system. The second bioassay evaluated the sublethal concentrations of the persistent insecticides (formetanate, dimethoate, spinosad). Increasing the concentrations of the insecticides increased the number that were classified as persistent. In the third bioassay, evaluation of the differential toxicity of eight insecticides to the ACP and the parasitoid showed that chlorpyrifos and bifenthrin were more harmful to T. radiata. Therefore, these two insecticides are not recommended for application at the time of parasitoid release. Cypermethrin, imidacloprid, and dimethoate caused higher mortality of D. citri and are most often recommended in IPM programs. The choice of an insecticide for the control of citrus pests must be made with care, aiming to preserve the natural enemies in the ecosystem, and thereby contribute to the success of biological control.

  8. A fixed-dose approach to conducting emamectin benzoate tolerance assessments on field-collected sea lice, Lepeophtheirus salmonis.

    PubMed

    Whyte, S K; Westcott, J D; Elmoslemany, A; Hammell, K L; Revie, C W

    2013-03-01

    In New Brunswick, Canada, the sea louse, Lepeophtheirus salmonis, poses an on-going management challenge to the health and productivity of commercially cultured Atlantic salmon, Salmo salar. While the in-feed medication, emamectin benzoate (SLICE® ; Merck), has been highly effective for many years, evidence of increased tolerance has been observed in the field since late 2008. Although bioassays on motile stages are a common tool to monitor sea lice sensitivity to emamectin benzoate in field-collected sea lice, they require the collection of large numbers of sea lice due to inherent natural variability in the gender and stage response to chemotherapeutants. In addition, sensitive instruments such as EC(50) analysis may be unnecessarily complex to characterize susceptibility subsequent to a significant observed decline in efficacy. This study proposes an adaptation of the traditional, dose-response format bioassay to a fixed-dose method. Analysis of 657 bioassays on preadult and adult stages of sea lice over the period 2008-2011 indicated a population of sea lice in New Brunswick with varying degrees of susceptibility to emamectin benzoate. A seasonal and spatial effect was observed in the robustness of genders and stages of sea lice, which suggest that mixing different genders and stages of lice within a single bioassay may result in pertinent information being overlooked. Poor survival of adult female lice in bioassays, particularly during May/June, indicates it may be prudent to consider excluding this stage from bioassays conducted at certain times of the year. This work demonstrates that fixed-dose bioassays can be a valuable technique in detecting reduced sensitivity in sea lice populations with varying degrees of susceptibility to emamectin benzoate treatments. © 2013 Blackwell Publishing Ltd.

  9. Genotoxicity of soil from farmland irrigated with wastewater using three plant bioassays.

    PubMed

    Cabrera, G L; Rodriguez, D M

    1999-05-19

    Three well known plant bioassays, the Allium root chromosome aberration (AL-RAA) assay, the Tradescantia micronucleus (Trad-MCN) assay, and the Tradescantia stamen hair (Trad-SHM) mutation assay were validated in 1991 by the International Programme on Chemical Safety (IPCS) under the auspices of the World Health Organization, and the United Nations Environment Programme (UNEP). These plant bioassays have proven to be efficient tests for chemical screening and especially for in situ monitoring for genotoxicity of environmental pollutants. As a result of this validation study, standard protocols of these three plant bioassays were used by some of the 11 participating countries in the IPCS to carry on genotoxicity tests on air, water and soil as a follow up activity. In the city of Queretaro, Mexico, wastewater coming from both industrial and domestic sources and without any treatment is used to irrigate the farm crops, polluting the soil. Potentially the pollutants could reach the food chain. For the above reason, soil irrigated with wastewater was sampled and monitored for the presence of genotoxic agents using the above three bioassays. Extracts from soil samples were made using distilled water and organic solvents by shaking the sample for about 12 h under a relatively low temperature (15-20 degrees C). Plant cuttings of Tradescantia or the roots of Allium were treated by submerging them in the extracts. Three replicates of each sample were analyzed in each of the three bioassays. Extracts using DMSO, ethanol and distilled water tested positive in the three bioassays and there were no differences for the genotoxicity of the extracts with the different solvents. Copyright 1999 Elsevier Science B.V.

  10. 40 CFR 124.213 - What procedures must I follow to make routine changes with prior approval?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... routine changes with prior approval? 124.213 Section 124.213 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS PROCEDURES FOR DECISIONMAKING Procedures for RCRA Standardized Permit Maintaining A Standardized Permit § 124.213 What procedures must I follow to make routine changes...

  11. 40 CFR 124.213 - What procedures must I follow to make routine changes with prior approval?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... routine changes with prior approval? 124.213 Section 124.213 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS PROCEDURES FOR DECISIONMAKING Procedures for RCRA Standardized Permit Maintaining A Standardized Permit § 124.213 What procedures must I follow to make routine changes...

  12. 40 CFR 124.212 - What procedures must I follow to make routine changes?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... routine changes? 124.212 Section 124.212 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS PROCEDURES FOR DECISIONMAKING Procedures for RCRA Standardized Permit Maintaining A Standardized Permit § 124.212 What procedures must I follow to make routine changes? (a) You can...

  13. 40 CFR 124.213 - What procedures must I follow to make routine changes with prior approval?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... routine changes with prior approval? 124.213 Section 124.213 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS PROCEDURES FOR DECISIONMAKING Procedures for RCRA Standardized Permit Maintaining A Standardized Permit § 124.213 What procedures must I follow to make routine changes...

  14. Sharing electronic structure and crystallographic data with ETSF_IO

    NASA Astrophysics Data System (ADS)

    Caliste, D.; Pouillon, Y.; Verstraete, M. J.; Olevano, V.; Gonze, X.

    2008-11-01

    We present a library of routines whose main goal is to read and write exchangeable files (NetCDF file format) storing electronic structure and crystallographic information. It is based on the specification agreed inside the European Theoretical Spectroscopy Facility (ETSF). Accordingly, this library is nicknamed ETSF_IO. The purpose of this article is to give both an overview of the ETSF_IO library and a closer look at its usage. ETSF_IO is designed to be robust and easy to use, close to Fortran read and write routines. To facilitate its adoption, a complete documentation of the input and output arguments of the routines is available in the package, as well as six tutorials explaining in detail various possible uses of the library routines. Catalogue identifier: AEBG_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEBG_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Gnu Lesser General Public License No. of lines in distributed program, including test data, etc.: 63 156 No. of bytes in distributed program, including test data, etc.: 363 390 Distribution format: tar.gz Programming language: Fortran 95 Computer: All systems with a Fortran95 compiler Operating system: All systems with a Fortran95 compiler Classification: 7.3, 8 External routines: NetCDF, http://www.unidata.ucar.edu/software/netcdf Nature of problem: Store and exchange electronic structure data and crystallographic data independently of the computational platform, language and generating software Solution method: Implement a library based both on NetCDF file format and an open specification (http://etsf.eu/index.php?page=standardization)

  15. Application of Bioassays for the Ecotoxicity Assessment of Contaminated Soils

    NASA Astrophysics Data System (ADS)

    Fernández, María D.; Babín, Mar; Tarazona, José V.

    The use of bioassays for soil characterization is receiving significant attention as a complementary tool to chemical analysis. Bioassays consist of direct toxicity assays of environmental samples that are transferred to the laboratory and analyzed for toxicity against selected organisms. Such soil samples contain the combination of the different pollutants present in situ and enable factors such as the bioavailability of contaminants or the interactions (synergic and antagonic) between them to be simultaneously studied.

  16. Comparison of chemical-activated luciferase gene expression bioassay and gas chromatography for PCB determination in human serum and follicular fluid.

    PubMed Central

    Pauwels, A; Cenijn, P H; Schepens, P J; Brouwer, A

    2000-01-01

    We assessed exposure to dioxin-like compounds using chemical and bioassay analysis in different matrices in a female population. A total of 106 serum and 9 follicular fluid samples were collected from infertile women attending Centers for Reproductive Medicine in Belgium from 1996 to 1998. Major polychlorinated biphenyl (PCB) congeners were quantified by chemical analysis using gas chromatography with electron-capture detection, and the chemical-activated luciferase gene expression (CALUX) bioassay was used to determine the total dioxin-like toxic equivalence (TEQ) of mixtures of polyhalogenated aromatic hydrocarbons present in body fluids, such as serum and follicular fluid. To the best of our knowledge, this is the first investigation to determine TEQ values by the CALUX bioassay in follicular fluid. The TEQ levels in both matrices are well correlated (r = 0.83, p = 0.02). As the chemical and bioassay analysis executed in this study do not cover the same span of polyhalogenated aromatic hydrocarbons, we did not expect totally correlated results. Moreover, the sample workup and quantification of the analytes differed completely. Nonetheless, the TEQ values in human extracts correlated well with the sum of four major PCB congeners chemically determined in both serum and follicular fluid. These results indicate that the CALUX bioassay may serve as a simple, relatively inexpensive prescreening tool for exposure assessment in epidemiologic surveys. Images Figure 1 Figure 2 PMID:10856030

  17. Measurement characteristics of the levels of institutionalization scales: examining reliability and validity.

    PubMed

    Barab, S A; Redman, B K; Froman, R D

    1998-01-01

    The Level of Institutionalization (LoIn) scales were developed to assess the extent to which a health promotion program has become integrated into a health care organization. The instrument was designed specifically to measure the amount of routinization and niche saturation of four subsystems (production, maintenance, supportive, and managerial) believed to make up an organization. In this study, the LoIn scales were completed for diabetes programs in 102 general hospitals and 30 home health agencies in Maryland and Pennsylvania. Reliability estimates across the four subsystems for routines (alpha = .61) and for niche saturation (alpha = .44) were substandard. Average correlation among the four subsystems for routines was .67, and among the four subsystems for niche saturation was .38, indicating moderate to large amounts of shared variance among subsystems and challenging claims of discriminant validity. Given these large correlations and a poor fit when testing the eight-factor model, higher-order confirmatory factor analyses were carried out. Results supported the existence of two second-order factors. When collapsed into two factors, the reliabilities were adequate (routines alpha = .90; niche saturation alpha = .80). Criterion-related validity also was found between length of program existence and the routine factor.

  18. How to translate a bioassay into a screening assay for natural products: general considerations and implementation of antimicrobial screens.

    PubMed

    Fallarero, Adyary; Hanski, Leena; Vuorela, Pia

    2014-09-01

    Natural product sources have been a valuable provider of molecular diversity in many drug discovery programs and several therapeutically important drugs have been isolated from these. However, the screening of such materials can be very complicated due to the fact that they contain a complex mixture of secondary metabolites, but also the purified natural compounds exert a challenge for bioactivity screening. Success in identifying new therapeutics using in vitro bioassays is largely dependent upon the proper design, validation, and implementation of the screening assay. In this review, we discuss some aspects which are of significant concern when screening natural products in a microtiter plate-based format, being partly applicable to other assay formats as well, such as validation parameters, layouts for assay protocols, and common interferences caused by natural products samples, as well as various troubleshooting strategies. Examples from the field of natural product drug discovery of antibacterial compounds are discussed, and contributions from the realm of academic screenings are highlighted. Georg Thieme Verlag KG Stuttgart · New York.

  19. Bioassay-guided investigation of two Monarda essential oils as repellents of yellow fever mosquito Aedes aegypti.

    PubMed

    Tabanca, Nurhayat; Bernier, Ulrich R; Ali, Abbas; Wang, Mei; Demirci, Betul; Blythe, Eugene K; Khan, Shabana I; Baser, K Husnu Can; Khan, Ikhlas A

    2013-09-11

    As part of an ongoing research program to identify active mosquito repellents, Monarda bradburiana Beck and Monarda fistulosa L. essential oils showed good repellent activity with minimum effective dosages (MED) of 0.055 ± 0.036 and 0.078 ± 0.027 mg/cm(2), respectively, compared to reference standard N,N-diethyl-3-methylbenzamide (DEET) (0.039 ± 0.014 mg/cm(2)). Systematic bioassay-guided fractionation of essential oils of both Monarda species was performed to identify the active repellent compounds, and isolated pure compounds were individually tested for repellency. Of the isolated compounds, carvacrol, thymol, eugenol, and carvacrol methyl ether were found to be the repellent compounds with MEDs in the range of 0.013-0.063 mg/cm(2). Active repellent compounds were also tested for larvicidal activity against 1-day-old Aedes aegypti larvae. Thymol was the best larvicide among the tested individual compounds (LD50 of 13.9 ppm). None of the individual compounds showed cytotoxicity against mammalian cells; however, the essential oils were toxic to all cell lines.

  20. Rainfastness and residual activity of insecticides to control Japanese beetle (Coleoptera: scarabaeidae) in Grapes.

    PubMed

    Hulbert, Daniel; Isaacs, Rufus; Vandervoort, Christine; Wise, John C

    2011-10-01

    Field-based bioassays and residue profile analysis were used to determine the relative toxicity, rainfastness, and field degradation over time of five insecticides from five insecticide classes on adult Japanese beetles, Popillia japonica Newman (Coleoptera: Scarabaeidae), in grapes, Vitis labrusca L. Bioassays assessed Japanese beetle condition as alive, knockdown, or immobile when exposed for 24 h or 7-d field-aged residues of phosmet, carbaryl, bifenthrin, thiamethoxam, or indoxacarb after 0, 12.7, or 25.4 mm of rain had been simulated. We found that the two most toxic insecticides to Japanese beetle were phosmet and carbaryl, followed by bifenthrin, thiamethoxam, and then indoxacarb. The efficacy of phosmet decreased because of rainfall, but not because of field aging. The efficacy of carbaryl decreased because of rainfall and field aging. The efficacies of bifenthrin and thiamethoxam were not affected by rainfall but decreased because of field aging. The efficacy of indoxacarb was not affected by rainfall or field aging. This study will help vineyard managers make informed decisions on when reapplications of insecticides are needed with the aim of improving integrated pest management programs.

  1. Utilization of a duckweed bioassay to evaluate leaching of heavy metals in smelter contaminated soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Youngman, A.L.; Lydy, M.J.; Williams, T.L.

    1998-12-31

    The purpose of this study was to determine whether a duckweed bioassay could be used to evaluate the downward migration of heavy metals in smelter soils. The duckweed bioassay was initially used to evaluate elutriates prepared from samples of smelter soils. These initial tests verified that the elutriates would elicit toxic responses. Elutriate testing was followed with an evaluation of leachate from untreated soil cores or soil cores that had been amended with organic matter either unplanted or planted to a grass-forb seed mixture. There was an inverse linear relationship between heavy-metal concentrations in leachate and NOEC and IC{sub 50}more » values expressed as percentages among all soil cores. Based on these preliminary duckweed bioassays, there were no differences between soil types or organic amended or non-amended soil, but leachate from vegetated soil cores were less toxic than were leachates from non-vegetated soil cores. Overall, the duckweed bioassays were useful in detecting heavy metal availability in elutriate and leachate samples from smelter soils.« less

  2. Assessment of the genotoxicity of 137Cs radiation using Vicia-micronucleus, Tradescantia-micronucleus and Tradescantia-stamen-hair mutation bioassays.

    PubMed

    Minouflet, Marion; Ayrault, Sophie; Badot, Pierre-Marie; Cotelle, Sylvie; Ferard, Jean-François

    2005-01-01

    Since the middle of the 20th century, ionizing radiations from radioactive isotopes including 137Cs have been investigated to determine their genotoxic impact on living organisms. The present study was designed to compare the effectiveness of three plant bioassays to assess DNA damage induced by low doses of 137Cs: Vicia-micronucleus test (Vicia-MCN), Tradescantia-micronucleus test (Trad-MCN) and Tradescantia-stamen-hair mutation test (Trad-SH) were used. Vicia faba (broad bean) and Tradescantia clone 4430 (spiderwort) were exposed to 137Cs according to different scenarios: external and internal (contamination) irradiations. Experiments were conducted with various levels of radioactivity in solution or in soil, using solid or liquid 137Cs sources. The three bioassays showed different sensitivities to the treatments. Trad-MCN appeared to be the most sensitive test (significative response from 1.5 kBq/200 ml after 30 h of contamination). Moreover, at comparable doses, internal irradiations led to larger effects for the three bioassays. These bioassays are effective tests for assessing the genotoxic effects of radioactive 137Cs pollution.

  3. Environmental legislation and aquatic ecotoxicology in Mexico: past, present and future scenarios.

    PubMed

    Mendoza-Cantú, Ania; Ramírez-Romero, Patricia; Pica-Granados, Yolanda

    2007-08-01

    The consolidation of environmental legislation is fundamental for governments that wish to support and promote different actions focused on reducing pollution and protecting natural water resources in order to maintain the present and future benefits that water provides for human beings and wild life. Environmental laws are essential for sustaining human activities and health, preserving biodiversity and promoting sustainable development. In this context, it is important that environmental regulations concentrate on preventing or reducing the harmful impact of pollutants on organisms and ecosystems. The introduction of toxicity bioassays in environmental regulations is a positive step toward achieving this goal. In Mexico, the development of environmental legislation and the introduction of bioassays in water regulation are part of a very recent and complex journey. This article describes how aquatic ecotoxicology tools, particularly bioassays, have influenced water pollution policies in Mexico. Three scenarios are reviewed: the background of Mexican legislation on water protection and Mexico's participation in the Watertox project; the actual efforts of SEMARNAT to develop bioassay batteries for this country; and, the challenges and perspectives of ecotoxicological bioassays as regulatory instruments.

  4. 75 FR 48698 - Medicare, Medicaid and CLIA Programs; COLA (Formerly the Commission on Office Laboratory...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-11

    ..., including Syphilis Serology, General Immunology. Chemistry, including Routine Chemistry, Urinalysis.... Chemistry, including Routine Chemistry, Urinalysis, Endocrinology, Toxicology. Hematology. Immunohematology...

  5. Development of Intake Retention, and Excretion Fractions used in Bioassay Programs for Metallic Nanoparticle Aerosols Produced in Modern Munitions Development

    DTIC Science & Technology

    2014-03-01

    potential toxicological effects of tungsten-compounds are often attributed to the presence of cobalt and or chromium which are frequently contained in...rat test subjects.4 These claims were later put in doubt because of the substantial presents of chromium and cobalt in the tungsten alloy. Very little...biokinetics of aluminum follow similar trends as other trivalent metals. Of specific importance to this work, Priest made the assertion that

  6. Carbon-14 bioassay for decommissioning of Hanford reactors.

    PubMed

    Carbaugh, Eugene H; Watson, David J

    2012-05-01

    The production reactors at the U.S. Department of Energy Hanford Site used large graphite piles as the moderator. As part of long-term decommissioning plans, the potential need for ¹⁴C radiobioassay of workers was identified. Technical issues associated with ¹⁴C bioassay and worker monitoring were investigated, including anticipated graphite characterization, potential intake scenarios, and the bioassay capabilities that may be required to support the decommissioning of the graphite piles. A combination of urine and feces sampling would likely be required for the absorption type S ¹⁴C anticipated to be encountered. However, the concentrations in the graphite piles appear to be sufficiently low that dosimetrically significant intakes of ¹⁴C are not credible, thus rendering moot the need for such bioassay.

  7. The effect of pesticide residue on caged mosquito bioassays.

    PubMed

    Barber, J A S; Greer, Mike; Coughlin, Jamie

    2006-09-01

    Wind tunnel experiments showed that secondary pickup of insecticide residue by mosquitoes in cage bioassays had a significant effect on mortality. Cage bioassays using adult Ochlerotatus taeniorhynchus (Wiedemann) investigated the effect of exposure time to a contaminated surface. Cages were dosed in a wind tunnel using the LC50 for naled (0.124 mg a.i./ml) and an LC25 (0.0772 mg a.i./ml) for naled. Half of the bioassay mosquitoes were moved directly into clean cages with the other half remaining in the sprayed, hence contaminated, cage. Treatment mortality was assessed at 8, 15, 30, 60, 120, 240, and 1,440 min postapplication. Cage contamination had a significant effect on mosquito mortality for both the LC25 and LC50 between 15 and 30 min postapplication.

  8. Carbon-14 Bioassay for Decommissioning of Hanford Reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carbaugh, Eugene H.; Watson, David J.

    2012-05-01

    The old production reactors at the US Department of Energy Hanford Site used large graphite piles as the moderator. As part of long-term decommissioning plans, the potential need for 14C radiobioassay of workers was identified. Technical issues associated with 14C bioassay and worker monitoring were investigated, including anticipated graphite characterization, potential intake scenarios, and the bioassay capabilities that may be required to support the decommissioning of the graphite piles. A combination of urine and feces sampling would likely be required for the absorption type S 14C anticipated to be encountered. However the concentrations in the graphite piles appear to bemore » sufficiently low that dosimetrically significant intakes of 14C are not credible, thus rendering moot the need for such bioassay.« less

  9. 32 CFR Appendix C to Part 806b - DoD ‘Blanket Routine Uses’

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false DoD âBlanket Routine Usesâ C Appendix C to Part... PRIVACY ACT PROGRAM Pt. 806b, App. C Appendix C to Part 806b—DoD ‘Blanket Routine Uses’ Certain DoD... the issuance of a license, grant, or other benefit. c. Disclosure of Requested Information Routine Use...

  10. 32 CFR Appendix C to Part 806b - DoD ‘Blanket Routine Uses’

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false DoD âBlanket Routine Usesâ C Appendix C to Part... PRIVACY ACT PROGRAM Pt. 806b, App. C Appendix C to Part 806b—DoD ‘Blanket Routine Uses’ Certain DoD... the issuance of a license, grant, or other benefit. c. Disclosure of Requested Information Routine Use...

  11. Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

    PubMed

    Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

    2016-05-01

    The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Construction of a nontoxigenic Clostridium botulinum strain for food challenge studies.

    PubMed

    Bradshaw, Marite; Marshall, Kristin M; Heap, John T; Tepp, William H; Minton, Nigel P; Johnson, Eric A

    2010-01-01

    Clostridium botulinum produces the most poisonous natural toxin known and is a perennial concern to the food industry and to regulatory agencies due to the potential threat of food-borne botulism. To ensure the botulinal safety of foods, rigorous food challenge testing to validate food-processing conditions and food formulations has been routinely performed. Detection of the botulinum neurotoxin is performed by using a mouse bioassay and/or in vitro assays. There has been considerable interest by the food industry and regulatory agencies in minimizing or even replacing the use of animals in these challenge studies. In addition, due to stringent select-agent regulations, the testing of various foods using toxigenic C. botulinum strains requires facilities and personnel that are certified for work with this organism. For this purpose we propose to generate sets of nontoxigenic C. botulinum strains from proteolytic and nonproteolytic groups that differ from the wild-type strains only by their inability to produce botulinum neurotoxin. In this initial study we describe the generation of a nontoxigenic mutant of C. botulinum strain 62A using the ClosTron mutagenesis system by inserting a group II intron into the botulinum neurotoxin type A gene (bont/A). The mutant clones were nontoxigenic as determined by Western blots and mouse bioassays but showed physiological characteristics, including growth properties and sporulation, that were similar to those of the parent strain in laboratory media. Additional studies will be required to evaluate comparable characteristics in various food matrices. The availability of suitable nontoxigenic C. botulinum strains for food challenge studies will be beneficial for enhancing the botulinal safety of foods as well as increasing the biosafety of workers and may eliminate the use of laboratory animals.

  13. Water quality bioassay using selected protozoa. I. [Paramecium candatum; Amoeba proteus; Euglena gracilis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mills, W.L.

    1976-01-01

    The suitability of certain species of protozoa as indicators of water quality has been determined. Experiments were conducted under laboratory conditions to standardize a bioassay procedure for water quality using either Paramecium caudatum, Amoeba proteus, or Euglena gracilis as the indicator organism. The bioassay, which consists of exposing the organisms to a known concentration of pollutant under laboratory conditions, followed by microscopic observation to establish the time of death, affords a reliable, convenient and inexpensive way to monitor for water quality.

  14. Use of a modified microplate bioassay method to investigate antibacterial activity in the Peruvian medicinal plant Peperomia galioides.

    PubMed

    Langfield, Richard D; Scarano, Frank J; Heitzman, Mary E; Kondo, Miwako; Hammond, Gerald B; Neto, Catherine C

    2004-10-01

    A versatile microplate bioassay for quick and sensitive determination of antibacterial activity was developed for use in screening medicinal plants and identification of their active principles. This assay can be used to determine minimum inhibitory concentrations for small quantities of organic or water-soluble plant extracts. Bioassay-guided fractionation of the stem and leaves of Peperomia galioides using this method found fractions containing grifolin and grifolic acid, which inhibited growth of Staphylococcus aureus and Staphylococcus epidermidis.

  15. Aspartame and Risk of Cancer: A Meta-analytic Review.

    PubMed

    Mallikarjun, Sreekanth; Sieburth, Rebecca McNeill

    2015-01-01

    Aspartame (APM) is the most commonly used artificial sweetener and flavor enhancer in the world. There is a rise in concern that APM is carcinogenic due to a variation in the findings of the previous APM carcinogenic bioassays. This article conducts a meta-analytic review of all previous APM carcinogenic bioassays on rodents that were conducted before 31 December 2012. The search yielded 10 original APM carcinogenic bioassays on rodents. The aggregate effect sizes suggest that APM consumption has no significant carcinogenic effect in rodents.

  16. Performance and determinants of routine immunization coverage within the context of intensive polio eradication activities in Uttar Pradesh, India: Social Mobilization Network (SM Net) and Core Group Polio Project (CGPP)

    PubMed Central

    2013-01-01

    Background Studies that have looked at the effect of polio eradication efforts in India on routine immunization programs have provided mixed findings. One polio eradication project, funded by US Agency for International Development (USAID) and carried out by the CORE Group Polio Project (CGPP) in the state of Uttar Pradesh of India, has included the strengthening of routine immunization systems as a core part of its polio eradication strategy. This paper explores the performance of routine immunization services in the CGPP intervention areas concurrent with intensive polio eradication activities. The paper also explores determinants of routine immunization performance such as caretaker characteristics and CGPP activities to strengthen routine immunization services. Methods We conduct secondary data analysis of the latest project household immunization survey in 2011 and compare these findings to reports of past surveys in the CGPP program area and at the Uttar Pradesh state level (as measured by children’s receipt of DPT vaccinations). This is done to judge if there is any evidence that routine immunization services are being disrupted. We also model characteristics of survey respondents and respondents’ exposure to CGPP, communication activities against their children’s receipt of key vaccinations in order to identify determinants of routine immunization coverage. Results Routine immunization coverage has increased between the first survey (2005 for state level estimates, 2008 for the CGPP program) and the latest (2011 for both state level and CGPP areas), as measured by children’s receipt of DPT vaccination. This increase occurred concurrent with polio eradication efforts intensive enough to result in interruption of transmission. In addition, a mothers’ exposure to specific communication materials, her religion and education were associated with whether or not her children receive one or more doses of DPT. Conclusions A limitation of the analysis is the absence of a controlled comparison. It is possible routine immunization coverage would have increased even more in the absence of polio eradication efforts. At the same time, however, there is no evidence that routine immunization services were disrupted by polio eradication efforts. Targeted health communications are helpful in improving routine immunization performance. Strategies to address other determinants of routine immunization, such as religion and education, are also needed to maximize coverage. PMID:23680228

  17. Sustainability of ARV provision in developing countries: challenging a framework based on program history.

    PubMed

    Azeredo, Thiago Botelho; Oliveira, Maria Auxiliadora; Santos-Pinto, Cláudia Du Bocage; Miranda, Elaine Silva; Osorio-de-Castro, Claudia Garcia Serpa

    2017-08-01

    The provision of ARVs is central to HIV/AIDS programs, because of its impact on the course of the disease and on quality of life. Although first-line treatments costs have declined, treatment-associated expenses are steeper each year. Sustainability is therefore an important variable for the success of treatment programs. A conceptual framework on sustainability of ARV provision was developed, followed by data collection instruments. The pilot study was undertaken in Brazil. Bolivia, Peru and Mozambique, were visited. Key informants were identified and interviewed. Investigation of sustainability related to ARV provision involved implementation and routinization events of provision schemes. Evidence of greater sustainability potential was observed in Peru, where provision is implemented and routinized by the National HIV/AIDS program and expenditures met by the government. In Mozambique, provision is dependent on donations and external aid, but the country displays a great effort to incorporate ARV provision and care in routine healthcare activities. Bolivia, in addition to external dependence on financing and management of drug supply, presents problems regarding implementation and routinization. The conceptual framework was useful in recognizing events that influence sustainable ARV provision in these countries.

  18. Paper-based chromatic toxicity bioassay by analysis of bacterial ferricyanide reduction.

    PubMed

    Pujol-Vila, F; Vigués, N; Guerrero-Navarro, A; Jiménez, S; Gómez, D; Fernández, M; Bori, J; Vallès, B; Riva, M C; Muñoz-Berbel, X; Mas, J

    2016-03-03

    Water quality assessment requires a continuous and strict analysis of samples to guarantee compliance with established standards. Nowadays, the increasing number of pollutants and their synergistic effects lead to the development general toxicity bioassays capable to analyse water pollution as a whole. Current general toxicity methods, e.g. Microtox(®), rely on long operation protocols, the use of complex and expensive instrumentation and sample pre-treatment, which should be transported to the laboratory for analysis. These requirements delay sample analysis and hence, the response to avoid an environmental catastrophe. In an attempt to solve it, a fast (15 min) and low-cost toxicity bioassay based on the chromatic changes associated to bacterial ferricyanide reduction is here presented. E. coli cells (used as model bacteria) were stably trapped on low-cost paper matrices (cellulose-based paper discs, PDs) and remained viable for long times (1 month at -20 °C). Apart from bacterial carrier, paper matrices also acted as a fluidic element, allowing fluid management without the need of external pumps. Bioassay evaluation was performed using copper as model toxic agent. Chromatic changes associated to bacterial ferricyanide reduction were determined by three different transduction methods, i.e. (i) optical reflectometry (as reference method), (ii) image analysis and (iii) visual inspection. In all cases, bioassay results (in terms of half maximal effective concentrations, EC50) were in agreement with already reported data, confirming the good performance of the bioassay. The validation of the bioassay was performed by analysis of real samples from natural sources, which were analysed and compared with a reference method (i.e. Microtox). Obtained results showed agreement for about 70% of toxic samples and 80% of non-toxic samples, which may validate the use of this simple and quick protocol in the determination of general toxicity. The minimum instrumentation requirements and the simplicity of the bioassay open the possibility of in-situ water toxicity assessment with a fast and low-cost protocol. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. 76 FR 4435 - Privacy Act of 1974; Report of Modified or Altered System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-25

    ... entry, computer systems analysis and computer programming services. The contractors promptly return data.... Proposed Routine Use Disclosures of Data in the System This System of Records contains information such as... compatible use of data is known as a ``routine use''. The routine uses proposed for this System are...

  20. Advanced flight design systems subsystem performance models. Sample model: Environmental analysis routine library

    NASA Technical Reports Server (NTRS)

    Parker, K. C.; Torian, J. G.

    1980-01-01

    A sample environmental control and life support model performance analysis using the environmental analysis routines library is presented. An example of a complete model set up and execution is provided. The particular model was synthesized to utilize all of the component performance routines and most of the program options.

  1. Computer Program For Linear Algebra

    NASA Technical Reports Server (NTRS)

    Krogh, F. T.; Hanson, R. J.

    1987-01-01

    Collection of routines provided for basic vector operations. Basic Linear Algebra Subprogram (BLAS) library is collection from FORTRAN-callable routines for employing standard techniques to perform basic operations of numerical linear algebra.

  2. ATLAS, an integrated structural analysis and design system. Volume 2: System design document

    NASA Technical Reports Server (NTRS)

    Erickson, W. J. (Editor)

    1979-01-01

    ATLAS is a structural analysis and design system, operational on the Control Data Corporation 6600/CYBER computers. The overall system design, the design of the individual program modules, and the routines in the ATLAS system library are described. The overall design is discussed in terms of system architecture, executive function, data base structure, user program interfaces and operational procedures. The program module sections include detailed code description, common block usage and random access file usage. The description of the ATLAS program library includes all information needed to use these general purpose routines.

  3. Methods for the isolation and identification of polycyclic aromatic hydrocarbons found in complex mixtures and the determination of their possible toxicity by means of a host mediated bioassay technique. Progress report, July 1, 1976--February 1, 1977. [Cultured mouse leumemia cell bioassay system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lipsky, S.R.; Alexander, G.; McMurray, W.

    1977-02-01

    Techniques were developed to produce excellent high performance glass capillary columns for gas chromatographic analyses of a wide range of complex mixtures of organic compounds, including those containing a wide array of polycyclic aromatic hydrocarbons (PAH) derived from a coal liquefaction process. Work was begun to assess the potential mutogenicity and/or carcinogenicity of the various isolated PAH fractions utilizing a unique host mediated bioassay system. Preliminary results indicate that further efforts will be required to determine dose response parameters of cultured mouse leukemia cells, as well as suitable vehicles for the satisfactory introduction of certain PAH fractions into this particularmore » bioassay system.« less

  4. Sensitivity of mouse bioassay in clinical wound botulism.

    PubMed

    Wheeler, Charlotte; Inami, Gregory; Mohle-Boetani, Janet; Vugia, Duc

    2009-06-15

    California has an ongoing epidemic of wound botulism (WB) among injection drug users (IDUs). We retrospectively studied a cohort of patients with WB and determined the sensitivity of the mouse bioassay-the gold standard laboratory test for confirmation of botulism-in verifying WB. We defined a clinical case of WB as an acute, bilateral, descending, flaccid paralysis starting with 1 cranial nerve palsies in an IDU with no other explainable diagnosis. We calculated the sensitivity of the mouse bioassay as the proportion of clinical WB cases that had positive serum toxin test results by mouse bioassay. We compared serum toxin-positive with serum toxin-negative patients. Of 73 patients with WB, 50 tested serum toxin positive, yielding a sensitivity of 68%. Serum toxin-positive patients did not differ significantly from serum toxin-negative patients with respect to demographic characteristics or injection drug use practices or in days from patient symptom onset to collection of specimens for testing. Patients did not differ significantly by clinical characteristics, except that serum toxin-positive patients were more likely than serum toxin-negative patients to have required mechanical ventilation during their hospital courses (74% vs. 43%; P = .01). In this study, the mouse bioassay failed to detect botulinum toxin in the serum samples of nearly one-third of IDUs with characteristic WB. Such patients should be considered to have probable WB. Physicians should be aware of the test's limitations and base their final diagnosis of suspected WB on clinical criteria when the mouse bioassay produces negative results.

  5. Natural products phytotoxicity A bioassay suitable for small quantities of slightly water-soluble compounds.

    PubMed

    Dornbos, D L; Spencer, G F

    1990-02-01

    A large variety of secondary metabolites that can inhibit germination and/or seedling growth are produced by plants in low quantities. The objective of this study was to develop a bioassay capable of reliably assessing reductions in germination percentage and seedling length of small-seeded plant species caused by exposure to minute quantities of these compounds. The germination and growth of alfalfa (Medicago saliva), annual ryegrass (Lolium multiflorum), and velvetleaf (Abutilon theophrasti) were evaluated against six known phytotoxins from five chemical classes; cinmethylin (a herbicidal cineole derivative) was selected as a comparison standard. Each phytotoxin, dissolved in a suitable organic solvent, was placed on water-agar in small tissue culture wells. After the solvent evaporated, imbibed seeds were placed on the agar; after three days, germination percentages and seedling lengths were measured. Compared to a commonly used filter paper procedure, this modified agar bioassay required smaller quantities of compound per seed for comparable bioassay results. This bioassay also readily permitted the measurement of seedling length, a more sensitive indicator of phytotoxicity than germination. Seedling length decreased sigmoidally as the toxin concentration increased logarithmically. Phytotoxicity was a function of both compound and plant species. Cinmethylin, a grass herbicide, reduced the length of annual ryegrass seedlings by 90-100%, whereas that of alfalfa and velvetleaf was inhibited slightly. The agar bioassay facilitated the rapid and reliable testing of slightly water-soluble compounds, requiring only minute quantities of each compound to give reproducible results.

  6. Development of a dual luciferase activity and fluorescamine protein assay adapted to a 384 micro-well plate format: Reducing variability in human luciferase transactivation cell lines aimed at endocrine active substances.

    PubMed

    Brennan, Jennifer C; Tillitt, Donald E

    2018-03-01

    There is a need to adapt cell bioassays to 384-well and 1536-well formats instead of the traditional 96-well format as high-throughput screening (HTS) demands increase. However, the sensitivity and performance of the bioassay must be re-verified in these higher micro-well plates, and verification of cell health must also be HT (high-throughput). We have adapted two commonly used human breast luciferase transactivation cell bioassays, the recently re-named estrogen agonist/antagonist screening VM7Luc4E2 cell bioassay (previously designated BG1Luc4E2) and the androgen/glucocorticoid screening MDA-kb2 cell bioassay, to 384-well formats for HTS of endocrine-active substances (EASs). This cost-saving adaptation includes a fast, accurate, and easy measurement of protein amount in each well via the fluorescamine assay with which to normalize luciferase activity of cell lysates without requiring any transfer of the cell lysates. Here we demonstrate that by accounting for protein amount in the cell lysates, antagonistic agents can easily be distinguished from cytotoxic agents in the MDA-kb2 and VM7Luc4E2 cell bioassays. Additionally, we demonstrate via the fluorescamine assay improved interpretation of luciferase activity in wells along the edge of the plate (the so-called "edge effect"), thereby increasing usable wells to the entire plate, not just interior wells. Published by Elsevier Ltd.

  7. Development of a dual luciferase activity and fluorescamine protein assay adapted to a 384 micro-well plate format: Reducing variability in human luciferase transactivation cell lines aimed at endocrine active substances

    USGS Publications Warehouse

    Brennan, Jennifer; Tillitt, Donald E.

    2018-01-01

    There is a need to adapt cell bioassays to 384-well and 1536-well formats instead of the traditional 96-well format as high-throughput screening (HTS) demands increase. However, the sensitivity and performance of the bioassay must be re-verified in these higher micro-well plates, and verification of cell health must also be HT (high-throughput). We have adapted two commonly used human breast luciferase transactivation cell bioassays, the recently re-named estrogen agonist/antagonist screening VM7Luc4E2 cell bioassay (previously designated BG1Luc4E2) and the androgen/glucocorticoid screening MDA-kb2 cell bioassay, to 384-well formats for HTS of endocrine-active substances (EASs). This cost-saving adaptation includes a fast, accurate, and easy measurement of protein amount in each well via the fluorescamine assay with which to normalize luciferase activity of cell lysates without requiring any transfer of the cell lysates. Here we demonstrate that by accounting for protein amount in the cell lysates, antagonistic agents can easily be distinguished from cytotoxic agents in the MDA-kb2 and VM7Luc4E2 cell bioassays. Additionally, we demonstrate via the fluorescamine assay improved interpretation of luciferase activity in wells along the edge of the plate (the so-called “edge effect”), thereby increasing usable wells to the entire plate, not just interior wells.

  8. Development, optimization and validation of a rapid colorimetric microplate bioassay for neomycin sulfate in pharmaceutical drug products.

    PubMed

    Francisco, Fabiane Lacerda; Saviano, Alessandro Morais; Pinto, Terezinha de Jesus Andreoli; Lourenço, Felipe Rebello

    2014-08-01

    Microbiological assays have been used to evaluate antimicrobial activity since the discovery of the first antibiotics. Despite their limitations, microbiological assays are widely employed to determine antibiotic potency of pharmaceutical dosage forms, since they provide a measure of biological activity. The aim of this work is to develop, optimize and validate a rapid colorimetric microplate bioassay for the potency of neomycin in pharmaceutical drug products. Factorial and response surface methodologies were used in the development and optimization of the choice of microorganism, culture medium composition, amount of inoculum, triphenyltetrazolium chloride (TTC) concentration and neomycin concentration. The optimized bioassay method was validated by the assessment of linearity (range 3.0 to 5.0μg/mL, r=0.998 and 0.994 for standard and sample curves, respectively), precision (relative standard deviation (RSD) of 2.8% and 4.0 for repeatability and intermediate precision, respectively), accuracy (mean recovery=100.2%) and robustness. Statistical analysis showed equivalency between agar diffusion microbiological assay and rapid colorimetric microplate bioassay. In addition, microplate bioassay had advantages concerning the sensitivity of response, time of incubation, and amount of culture medium and solutions required. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, J.M.; Callahan, C.A.; Cline, J.F.

    Bioassays were used in a three-phase research project to assess the comparative sensitivity of test organisms to known chemicals, determine if the chemical components in field soil and water samples containing unknown contaminants could be inferred from our laboratory studies using known chemicals, and to investigate kriging (a relatively new statistical mapping technique) and bioassays as methods to define the areal extent of chemical contamination. The algal assay generally was most sensitive to samples of pure chemicals, soil elutriates and water from eight sites with known chemical contamination. Bioassays of nine samples of unknown chemical composition from the Rocky Mountainmore » Arsenal (RMA) site showed that a lettuce seed soil contact phytoassay was most sensitive. In general, our bioassays can be used to broadly identify toxic components of contaminated soil. Nearly pure compounds of insecticides and herbicides were less toxic in the sensitive bioassays than were the counterpart commercial formulations. This finding indicates that chemical analysis alone may fail to correctly rate the severity of environmental toxicity. Finally, we used the lettuce seed phytoassay and kriging techniques in a field study at RMA to demonstrate the feasibility of mapping contamination to aid in cleanup decisions. 25 references, 9 figures, 9 tables.« less

  10. Image analysis library software development

    NASA Technical Reports Server (NTRS)

    Guseman, L. F., Jr.; Bryant, J.

    1977-01-01

    The Image Analysis Library consists of a collection of general purpose mathematical/statistical routines and special purpose data analysis/pattern recognition routines basic to the development of image analysis techniques for support of current and future Earth Resources Programs. Work was done to provide a collection of computer routines and associated documentation which form a part of the Image Analysis Library.

  11. 32 CFR 701.121 - Processing “routine use” disclosures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... DEPARTMENT OF THE NAVY DOCUMENTS AFFECTING THE PUBLIC DON Privacy Program § 701.121 Processing “routine use... be in writing and state that it is being made under a “routine use” established by a specific PA... and maintain a disclosure accounting of the information released. (See § 701.111.) (b) Failure to cite...

  12. Implementing a routine, voluntary HIV testing program in a Massachusetts county prison.

    PubMed

    Liddicoat, Rebecca V; Zheng, Hui; Internicola, Jeanne; Werner, Barbara G; Kazianis, Arthur; Golan, Yoav; Rubinstein, Eric P; Freedberg, Kenneth A; Walensky, Rochelle P

    2006-11-01

    Although U.S. prison inmates have higher rates of HIV infection than the general population, most inmates are not routinely tested for HIV infection at prison entry. The study objective was to implement a routine, voluntary HIV testing program in a Massachusetts county prison. During admission, inmates were given group HIV pre-test counseling and were subsequently offered private HIV testing. This intervention was compared to a control period during which HIV testing was provided only upon inmate or physician request. Between November 2004 and April 2005, 1,004 inmates met inclusion criteria and were offered routine, voluntary HIV testing. Of these, 734 (73.1%) accepted, 2 (0.3%) were HIV-infected, and 457 (45.5%) had been tested for HIV in the previous year. The testing rate of 73.1% was significantly increased from the rate of 18.0% (318 of 1,723) during the control period (p<0.001). Among the inmates tested for HIV in the prior year, 78.2% had received their last HIV test in the prison setting. Careful attention should be paid to prevent redundancy of testing efforts in the prison population. Implementing a routine HIV testing program among prison inmates greatly increased testing rates compared to on-request testing.

  13. Biological testing of a digested sewage sludge and derived composts.

    PubMed

    Moreira, R; Sousa, J P; Canhoto, C

    2008-11-01

    Aiming to evaluate a possible loss of soil habitat function after amendment with organic wastes, a digested sewage sludge and derived composts produced with green residues, where biologically tested in the laboratory using soil animals (Eisenia andrei and Folsomia candida) and plants (Brassica rapa and Avena sativa). Each waste was tested mimicking a field application of 6ton/ha or 12ton/ha. Avoidance tests did not reveal any impact of sludge and composts to soil biota. Germination and growth tests showed that application of composts were beneficial for both plants. Composts did not affect earthworm's mass increase or reproduction, but the highest sludge amendment revealed negative effects on both parameters. Only the amendment of composts at the highest dose originated an impairment of springtails reproductive output. We suggest that bioassays using different test species may be an additional tool to evaluate effects of amendment of organic wastes in soil. Biological tests are sensitive to pollutants at low concentrations and to interactions undetected by routine chemical analysis.

  14. Desert bighorn sheep mortality due to presumptive type C botulism in California

    USGS Publications Warehouse

    Swift, P.K.; Wehausen, J.D.; Ernest, H.B.; Singer, R.S.; Pauli, A.M.; Kinde, H.; Rocke, T.E.; Bleich, V.C.

    2000-01-01

    During a routine telemetry flight of the Mojave Desert (California, USA) in August 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (Ovis canadensis) in the vicinity of Old Dad Peak in San Bernardino County (California). A series of field investigations determined that at least 45 bighorn sheep had died near two artificial water catchments (guzzlers), including 13 bighorn sheep which had presumably drowned in a guzzler tank. Samples from water contaminated by decomposing bighorn sheep carcasses and hemolyzed blood from a fresh bighorn sheep carcass were tested for the presence of pesticides, heavy metals, strychnine, blue-green algae, Clostridium botulinum toxin, ethylene glycol, nitrates, nitrites, sodium, and salts. Mouse bioassay and enzyme-linked immunosorbent assay detected type C botulinum toxin in the hemolyzed blood and in fly larvae and pupae. This, coupled with negative results from other analyses, led us to conclude that type C botulinum poisoning was most likely responsible for the mortality of bighorn sheep outside the guzzler tank.

  15. Ascent/descent ancillary data production user's guide

    NASA Technical Reports Server (NTRS)

    Brans, H. R.; Seacord, A. W., II; Ulmer, J. W.

    1986-01-01

    The Ascent/Descent Ancillary Data Product, also called the A/D BET because it contains a Best Estimate of the Trajectory (BET), is a collection of trajectory, attitude, and atmospheric related parameters computed for the ascent and descent phases of each Shuttle Mission. These computations are executed shortly after the event in a post-flight environment. A collection of several routines including some stand-alone routines constitute what is called the Ascent/Descent Ancillary Data Production Program. A User's Guide for that program is given. It is intended to provide the reader with all the information necessary to generate an Ascent or a Descent Ancillary Data Product. It includes descriptions of the input data and output data for each routine, and contains explicit instructions on how to run each routine. A description of the final output product is given.

  16. Optimization and field use of a bioassay to monitor sea lice Lepeophtheirus salmonis sensitivity to emamectin benzoate.

    PubMed

    Westcott, Jillian D; Stryhn, Henrik; Burka, John F; Hammell, K Larry

    2008-04-01

    A bioassay for sea lice Lepeophtheirus salmonis sensitivity towards emamectin benzoate (EMB) was validated for field use. A probit regression model with natural responsiveness was used for the number of affected (moribund or dead) sea lice in bioassays involving different concentrations of EMB. Bioassay optimization included an evaluation of the inter-rater reliability of sea lice responsiveness to EMB and an evaluation of gender-related differences in susceptibility. Adoption of a set of bioassay response criteria improved the concordance (evaluated using the concordance correlation coefficient) between raters' assessments and the model estimation of EC50 values (the 'effective concentration' leading to a response of 50% of the lice not prone to natural response). An evaluation of gender-related differences in EMB susceptibility indicated that preadult stage female sea lice exhibited a significantly larger sensitivity towards EMB in 12 of 19 bioassays compared to preadult males. In order to evaluate sea lice sensitivity to EMB in eastern Canada, the intensive salmon farming area in the Bay of Fundy in southwestern New Brunswick was divided into 4 distinct regions based on industry health management practices and hydrographics. A total of 38 bioassays were completed from 2002 to 2005 using populations of preadult stage sea lice collected from Atlantic salmon Salmo salar farms within the 4 described regions. There was no significant overall effect of region or year on EC50 values; however, analysis of variance indicated a significant effect of time of year on EC50 values in 2002 and a potential effect in 2004 to 2005. Although the range of EC50 values obtained in this 3 yr study did not appear sufficient to affect current clinical success in the control of sea lice, the results suggest a seasonal- or temperature-associated variation in sensitivity to EMB. This will need to be considered if changes in EMB efficacy occur in the future.

  17. Integration of Microfractionation, qNMR and Zebrafish Screening for the In Vivo Bioassay-Guided Isolation and Quantitative Bioactivity Analysis of Natural Products

    PubMed Central

    Maes, Jan; Siverio-Mota, Dany; Marcourt, Laurence; Munck, Sebastian; Kamuhabwa, Appolinary R.; Moshi, Mainen J.; Esguerra, Camila V.; de Witte, Peter A. M.; Crawford, Alexander D.; Wolfender, Jean-Luc

    2013-01-01

    Natural products (NPs) are an attractive source of chemical diversity for small-molecule drug discovery. Several challenges nevertheless persist with respect to NP discovery, including the time and effort required for bioassay-guided isolation of bioactive NPs, and the limited biomedical relevance to date of in vitro bioassays used in this context. With regard to bioassays, zebrafish have recently emerged as an effective model system for chemical biology, allowing in vivo high-content screens that are compatible with microgram amounts of compound. For the deconvolution of the complex extracts into their individual constituents, recent progress has been achieved on several fronts as analytical techniques now enable the rapid microfractionation of extracts, and microflow NMR methods have developed to the point of allowing the identification of microgram amounts of NPs. Here we combine advanced analytical methods with high-content screening in zebrafish to create an integrated platform for microgram-scale, in vivo NP discovery. We use this platform for the bioassay-guided fractionation of an East African medicinal plant, Rhynchosia viscosa, resulting in the identification of both known and novel isoflavone derivatives with anti-angiogenic and anti-inflammatory activity. Quantitative microflow NMR is used both to determine the structure of bioactive compounds and to quantify them for direct dose-response experiments at the microgram scale. The key advantages of this approach are (1) the microgram scale at which both biological and analytical experiments can be performed, (2) the speed and the rationality of the bioassay-guided fractionation – generic for NP extracts of diverse origin – that requires only limited sample-specific optimization and (3) the use of microflow NMR for quantification, enabling the identification and dose-response experiments with only tens of micrograms of each compound. This study demonstrates that a complete in vivo bioassay-guided fractionation can be performed with only 20 mg of NP extract within a few days. PMID:23700445

  18. Bioassays for TSH Receptor Autoantibodies, from FRTL-5 Cells to TSH Receptor-LH/CG Receptor Chimeras: The Contribution of Leonard D. Kohn.

    PubMed

    Giuliani, Cesidio; Saji, Motoyasu; Bucci, Ines; Napolitano, Giorgio

    2016-01-01

    Since the discovery 60 years ago of the "long-acting thyroid stimulator" by Adams and Purves, great progress has been made in the detection of thyroid-stimulating hormone (TSH) receptor (TSHR) autoantibodies (TRAbs) in Graves' disease. Today, commercial assays are available that can detect TRAbs with high accuracy and provide diagnostic and prognostic evaluation of patients with Graves' disease. The present review focuses on the development of TRAbs bioassays, and particularly on the role that Leonard D. Kohn had in this. Indeed, 30 years ago, the Kohn group developed a bioassay based on the use of FRTL-5 cells that was characterized by high reproducibility, feasibility, and diagnostic accuracy. Using this FRTL-5 bioassay, Kohn and his colleagues were the first to develop monoclonal antibodies (moAbs) against the TSHR. Furthermore, they demonstrated the multifaceted functional nature of TRAbs in patients with Graves' disease, with the identification of stimulating and blocking TRAbs, and even antibodies that activated pathways other than cAMP. After the cloning of the TSHR, the Kohn laboratory constructed human TSHR-rat luteinizing hormone/chorionic gonadotropin receptor chimeras. This paved the way to a new bioassay based on the use of non-thyroid cells transfected with the Mc4 chimera. The new Mc4 bioassay is characterized by high diagnostic and prognostic accuracy, greater than for other assays. The availability of a commercial kit based on the Mc4 chimera is spreading the use of this assay worldwide, indicating its benefits for these patients with Graves' disease. This review also describes the main contributions made by other researchers in TSHR molecular biology and TRAbs assay, especially with the development of highly potent moAbs. A comparison of the diagnostic accuracies of the main TRAbs assays, as both immunoassays and bioassays, is also provided.

  19. Bioassays for TSH Receptor Autoantibodies, from FRTL-5 Cells to TSH Receptor–LH/CG Receptor Chimeras: The Contribution of Leonard D. Kohn

    PubMed Central

    Giuliani, Cesidio; Saji, Motoyasu; Bucci, Ines; Napolitano, Giorgio

    2016-01-01

    Since the discovery 60 years ago of the “long-acting thyroid stimulator” by Adams and Purves, great progress has been made in the detection of thyroid-stimulating hormone (TSH) receptor (TSHR) autoantibodies (TRAbs) in Graves’ disease. Today, commercial assays are available that can detect TRAbs with high accuracy and provide diagnostic and prognostic evaluation of patients with Graves’ disease. The present review focuses on the development of TRAbs bioassays, and particularly on the role that Leonard D. Kohn had in this. Indeed, 30 years ago, the Kohn group developed a bioassay based on the use of FRTL-5 cells that was characterized by high reproducibility, feasibility, and diagnostic accuracy. Using this FRTL-5 bioassay, Kohn and his colleagues were the first to develop monoclonal antibodies (moAbs) against the TSHR. Furthermore, they demonstrated the multifaceted functional nature of TRAbs in patients with Graves’ disease, with the identification of stimulating and blocking TRAbs, and even antibodies that activated pathways other than cAMP. After the cloning of the TSHR, the Kohn laboratory constructed human TSHR–rat luteinizing hormone/chorionic gonadotropin receptor chimeras. This paved the way to a new bioassay based on the use of non-thyroid cells transfected with the Mc4 chimera. The new Mc4 bioassay is characterized by high diagnostic and prognostic accuracy, greater than for other assays. The availability of a commercial kit based on the Mc4 chimera is spreading the use of this assay worldwide, indicating its benefits for these patients with Graves’ disease. This review also describes the main contributions made by other researchers in TSHR molecular biology and TRAbs assay, especially with the development of highly potent moAbs. A comparison of the diagnostic accuracies of the main TRAbs assays, as both immunoassays and bioassays, is also provided. PMID:27504107

  20. Bioassay for estimating the biogenic methane-generating potential of coal samples

    USGS Publications Warehouse

    Jones, Elizabeth J.P.; Voytek, Mary A.; Warwick, Peter D.; Corum, Margo D.; Cohn, Alexander G.; Bunnell, Joseph E.; Clark, Arthur C.; Orem, William H.

    2008-01-01

    Generation of secondary biogenic methane in coal beds is likely controlled by a combination of factors such as the bioavailability of coal carbon, the presence of a microbial community to convert coal carbon to methane, and an environment supporting microbial growth and methanogenesis. A set of treatments and controls was developed to bioassay the bioavailability of coal for conversion to methane under defined laboratory conditions. Treatments included adding a well-characterized consortium of bacteria and methanogens (enriched from modern wetland sediments) and providing conditions to support endemic microbial activity. The contribution of desorbed methane in the bioassays was determined in treatments with bromoethane sulfonic acid, an inhibitor of microbial methanogenesis. The bioassay compared 16 subbituminous coal samples collected from beds in Texas (TX), Wyoming (WY), and Alaska (AK), and two bituminous coal samples from Pennsylvania (PA). New biogenic methane was observed in several samples of subbituminous coal with the microbial consortium added, but endemic activity was less commonly observed. The highest methane generation [80 µmol methane/g coal (56 scf/ton or 1.75 cm3/g)] was from a south TX coal sample that was collected from a non-gas-producing well. Subbituminous coals from the Powder River Basin, WY and North Slope Borough, AK contained more sorbed (original) methane than the TX coal sample and generated 0–23 µmol/g (up to 16 scf/ton or 0.5 cm3/g) new biogenic methane in the bioassay. Standard indicators of thermal maturity such as burial depth, nitrogen content, and calorific value did not explain differences in biogenic methane among subbituminous coal samples. No original methane was observed in two bituminous samples from PA, nor was any new methane generated in bioassays of these samples. The bioassay offers a new tool for assessing the potential of coal for biogenic methane generation, and provides a platform for studying the mechanisms involved in this economically important activity.

  1. Highly variable sensitivity of five binding and two bio-assays for TSH-receptor antibodies.

    PubMed

    Diana, T; Wüster, C; Kanitz, M; Kahaly, G J

    2016-10-01

    TSH-receptor (TSHR) antibodies (Ab) can be measured with binding or bio-assays. Sensitivity and specificity of five binding and two bio-assays were compared. TSHR-blocking (TBAb) and TSHR-stimulating (TSAb) Ab were measured with reporter bio-assays. Blocking activity was defined as percent inhibition of luciferase expression relative to induction with bTSH alone. TSAb was reported as percentage of specimen-to-reference ratio (SRR%). TSHR-binding inhibitory immunoglobulins (TBII) were measured with Kronus, Dynex, Kryptor, Cobas, and Immulite. Sixty patients with Graves' disease (GD), 20 with Hashimoto's thyroiditis (HT), and 20 healthy controls (C) were included. C tested negative in all assays (specificity 100 %) while all 60 hyperthyroid GD patients tested positive in the TSAb bio-assay (sensitivity 100 %). Among these 60 GD patients, 20 had low TSAb positivity (SRR% 140-279), but were TBII positive in only 20 (100 %), 7 (35 %), 9 (45 %), 11 (55 %), and 18 (90 %) using the Kronus, Dynex, Kryptor, Cobas, and Immulite, respectively. In 20 moderate TSAb-positive (SRR% 280-420) patients, TBII tested positive in 20 (100 %), 14 (70 %), 13 (65 %), 16 (80 %), and 19 (95 %), respectively. The high (SRR% > 420) TSAb-positive patients were all TBII positive. All 20 hypothyroid HT patients tested TBAb positive (sensitivity 100 %) in the bio-assay while they tested TBII positive in 20 (100 %), 18 (90 %), 20, 20, and 18, respectively. Results obtained with two luminometers correlated for TSAb positive (r = 0.99, p < 0.001), TBAb positive (r = 0.88, p < 0.001), and C (r = 0.86, p < 0.001). None of the binding assays differentiated between TSAb and TBAb. Sensitivity is highly variable between binding and bio-assays for TSHR-Abs.

  2. In vitro bioassays to evaluate complex chemical mixtures in recycled water

    PubMed Central

    Jia, Ai; Escher, Beate I.; Leusch, Frederic D.L.; Tang, Janet Y.M.; Prochazka, Erik; Dong, Bingfeng; Snyder, Erin M.; Snyder, Shane A.

    2016-01-01

    With burgeoning population and diminishing availability of freshwater resources, the world continues to expand the use of alternative water resources for drinking, and the quality of these sources has been a great concern for the public as well as public health professionals. In vitro bioassays are increasingly being used to enable rapid, relatively inexpensive toxicity screening that can be used in conjunction with analytical chemistry data to evaluate water quality and the effectiveness of water treatment. In this study, a comprehensive bioassay battery consisting of 36 bioassays covering 18 biological endpoints was applied to screen the bioactivity of waters of varying qualities with parallel treatments. Samples include wastewater effluent, ultraviolet light (UV) and/or ozone advanced oxidation processed (AOP) recycled water, and infiltrated recycled groundwater. Based on assay sensitivity and detection frequency in the samples, several endpoints were highlighted in the battery, including assays for genotoxicity, mutagenicity, estrogenic activity, glucocorticoid activity, aryl hydrocarbon receptor activity, oxidative stress response, and cytotoxicity. Attenuation of bioactivity was found to be dependent on the treatment process and bioassay endpoint. For instance, ozone technology significantly removed oxidative stress activity, while UV based technologies were most efficient for the attenuation of glucocorticoid activity. Chlorination partially attenuated genotoxicity and greatly decreased herbicidal activity, while groundwater infiltration efficiently attenuated most of the evaluated bioactivity with the exception of genotoxicity. In some cases, bioactivity (e.g., mutagenicity, genotoxicity, and arylhydrocarbon receptor) increased following water treatment, indicating that transformation products of water treatment may be a concern. Furthermore, several types of bioassays with the same endpoint were compared in this study, which could help guide the selection of optimized methods in future studies. Overall, this research indicates that a battery of bioassays can be used to support decision-making on the application of advanced water treatment processes for removal of bioactivity. PMID:25989591

  3. In vitro bioassays to evaluate complex chemical mixtures in recycled water.

    PubMed

    Jia, Ai; Escher, Beate I; Leusch, Frederic D L; Tang, Janet Y M; Prochazka, Erik; Dong, Bingfeng; Snyder, Erin M; Snyder, Shane A

    2015-09-01

    With burgeoning population and diminishing availability of freshwater resources, the world continues to expand the use of alternative water resources for drinking, and the quality of these sources has been a great concern for the public as well as public health professionals. In vitro bioassays are increasingly being used to enable rapid, relatively inexpensive toxicity screening that can be used in conjunction with analytical chemistry data to evaluate water quality and the effectiveness of water treatment. In this study, a comprehensive bioassay battery consisting of 36 bioassays covering 18 biological endpoints was applied to screen the bioactivity of waters of varying qualities with parallel treatments. Samples include wastewater effluent, ultraviolet light (UV) and/or ozone advanced oxidation processed (AOP) recycled water, and infiltrated recycled groundwater. Based on assay sensitivity and detection frequency in the samples, several endpoints were highlighted in the battery, including assays for genotoxicity, mutagenicity, estrogenic activity, glucocorticoid activity, arylhydrocarbon receptor activity, oxidative stress response, and cytotoxicity. Attenuation of bioactivity was found to be dependent on the treatment process and bioassay endpoint. For instance, ozone technology significantly removed oxidative stress activity, while UV based technologies were most efficient for the attenuation of glucocorticoid activity. Chlorination partially attenuated genotoxicity and greatly decreased herbicidal activity, while groundwater infiltration efficiently attenuated most of the evaluated bioactivity with the exception of genotoxicity. In some cases, bioactivity (e.g., mutagenicity, genotoxicity, and arylhydrocarbon receptor) increased following water treatment, indicating that transformation products of water treatment may be a concern. Furthermore, several types of bioassays with the same endpoint were compared in this study, which could help guide the selection of optimized methods in future studies. Overall, this research indicates that a battery of bioassays can be used to support decision-making on the application of advanced water treatment processes for removal of bioactivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. The Environmental Heat Flux Routine, Version 4 (EHFR-4) and Multiple Reflections Routine (MRR). Volume 2: Programmers reference manual

    NASA Technical Reports Server (NTRS)

    Dietz, J. B.

    1973-01-01

    The EHFR program reference information which is presented consists of the following subprogram detailed data: purpose-description of the routine, a list of the calling programs, an argument list description, nomenclature definition, flow charts, and a compilation listing of each subprogram. Each of the EHFR subprograms were developed specifically for this routine and do not have an applicability of a general nature. Single precision accuracy available on the Univac 1108 is used exclusively in all but two of the 31 EHFR subprograms. The double precision variables required are identified in the nomenclature definition of the two subprograms that require them. A concise definition of the purpose, function, and capabilities is made in the subprogram description. The description references the appropriate Volume 1 sections of the report which contain the applicable detailed definitions, governing equations, and assumptions used. The compilation listing of each subprogram defines the program/data storage requirements, identifies the labeled block common data required, and identifies other subprograms called during execution. For Vol. 1, see N73-31842.

  5. Mixed-function oxidases and esterases associated with cross-resistance between DDT and lambda-cyhalothrin in Anopheles darlingi Root 1926 populations from Colombia.

    PubMed

    Fonseca-González, Idalyd; Quiñones, Martha L; McAllister, Janet; Brogdon, William G

    2009-02-01

    In order to establish the insecticide susceptibility status for Anopheles darlingi in Colombia, and as part of the National Network on Insecticide Resistance Surveillance, five populations of insects from three Colombian states were evaluated. Standardised WHO and CDC bottle bioassays, in addition to microplate biochemical assays, were conducted. Populations with mortality rates below 80% in the bioassays were considered resistant. All field populations were susceptible to deltamethrin, permethrin, malathion and fenitrothion. Resistance to lambda-cyhalothrin and DDT was detected in the Amé-Beté population using both bioassay methods with mortality rates of 65-75%. Enzyme levels related to insecticide resistance, including mixed function oxidases (MFO), non-specific esterases (NSE), glutathione S-transferases and modified acetylcholinesterase were evaluated in all populations and compared with a susceptible natural strain. Only mosquitoes from Amé-Beté presented significantly increased levels of both MFO and NSE, consistent with the low mortalities found in this population. The continued use of lambda-cyhalothrin for An. darlingi control in this locality has resulted in a natural resistance to this insecticide. In addition, DDT resistance is still present in this population, although this insecticide has not been used in Colombia since 1992. Increased metabolism through MFO and NSE may be involved in cross-resistance between lambda-cyhalothrin and DDT, although kdr-type nerve insensitivity cannot be discarded as a possible hypothesis. Additional research, including development of a kdr specific assay for An. darlingi should be conducted in future studies. Our data demonstrates the urgent need to develop local insecticide resistance management and surveillance programs throughout Colombia.

  6. Relationships among exceedences of metals criteria, the results of ambient bioassays, and community metrics in mining-impacted streams.

    PubMed

    Griffith, Michael B; Lazorchak, James M; Herlihy, Alan T

    2004-07-01

    If bioassessments are to help diagnose the specific environmental stressors affecting streams, a better understanding is needed of the relationships between community metrics and ambient criteria or ambient bioassays. However, this relationship is not simple, because metrics assess responses at the community level of biological organization, while ambient criteria and ambient bioassays assess or are based on responses at the individual level. For metals, the relationship is further complicated by the influence of other chemical variables, such as hardness, on their bioavailability and toxicity. In 1993 and 1994, U.S. Environmental Protection Agency (U.S. EPA) conducted a Regional Environmental Monitoring and Assessment Program (REMAP) survey on wadeable streams in Colorado's (USA) Southern Rockies Ecoregion. In this ecoregion, mining over the past century has resulted in metals contamination of streams. The surveys collected data on fish and macroinvertebrate assemblages, physical habitat, and sediment and water chemistry and toxicity. These data provide a framework for assessing diagnostic community metrics for specific environmental stressors. We characterized streams as metals-affected based on exceedence of hardness-adjusted criteria for cadmium, copper, lead, and zinc in water; on water toxicity tests (48-h Pimephales promelas and Ceriodaphnia dubia survival); on exceedence of sediment threshold effect levels (TELs); or on sediment toxicity tests (7-d Hyalella azteca survival and growth). Macroinvertebrate and fish metrics were compared among affected and unaffected sites to identify metrics sensitive to metals. Several macroinvertebrate metrics, particularly richness metrics, were less in affected streams, while other metrics were not. This is a function of the sensitivity of the individual metrics to metals effects. Fish metrics were less sensitive to metals because of the low diversity of fish in these streams.

  7. Development and validation of a streamlined method designed to detect residues of 62 veterinary drugs in bovine kidney using ultra-high performance liquid chromatography--tandem mass spectrometry.

    PubMed

    Lehotay, Steven J; Lightfield, Alan R; Geis-Asteggiante, Lucía; Schneider, Marilyn J; Dutko, Terry; Ng, Chilton; Bluhm, Louis; Mastovska, Katerina

    2012-08-01

    In the USA, the US Department of Agriculture's Food Safety and Inspection Service (FSIS) conducts the National Residue Program designed to monitor veterinary drug and other chemical residues in beef and other slaughtered food animals. Currently, FSIS uses a 7-plate bioassay in the laboratory to screen for antimicrobial drugs in bovine kidneys from those animals tested positive by inspectors in the slaughter establishments. The microbial inhibition bioassay has several limitations in terms of monitoring scope, sensitivity, selectivity, and analysis time. Ultra-high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) has many advantages over the bioassay for this application, and this study was designed to develop, evaluate, and validate a fast UHPLC-MS/MS method for antibiotics and other high-priority veterinary drugs in bovine kidney. Five existing multi-class, multi-residue methods from the literature were tested and compared, and each performed similarly. Experiments with incurred samples demonstrated that a 5-min shake of 2 g homogenized kidney with 10 ml of 4/1 (v/v) acetonitrile/water followed by simultaneous clean-up of the initial extract with 0.5 g C18 and 10 ml hexane gave a fast, simple, and effective sample preparation method for the <10 min UHPLC-MS/MS analysis. An extensive 5-day validation process demonstrated that the final method could be used to acceptably screen for 54 of the 62 drugs tested, and 50 of those met qualitative MS identification criteria. Quantification was not needed in the application, but the method gave ≥ 70% recoveries and ≤ 25% reproducibilities for 30 of the drugs. Published 2012. This article is a U.S. Government work and is in the public domain of the USA.

  8. Identification of a Putative Mexican Strain of Serratia entomophila Pathogenic against Root-Damaging Larvae of Scarabaeidae (Coleoptera)▿ †

    PubMed Central

    Nuñez-Valdez, M. Eugenia; Calderón, Marco A.; Aranda, Eduardo; Hernández, Luciano; Ramírez-Gama, Rosa M.; Lina, Laura; Rodríguez-Segura, Zitlhally; Gutiérrez, María del C.; Villalobos, Francisco J.

    2008-01-01

    The larvae of scarab beetles, known as “white grubs” and belonging to the genera Phyllophaga and Anomala (Coleoptera: Scarabaeidae), are regarded as soil-dwelling pests in Mexico. During a survey conducted to find pathogenic bacteria with the potential to control scarab larvae, a native Serratia sp. (strain Mor4.1) was isolated from a dead third-instar Phyllophaga blanchardi larva collected from a cornfield in Tres Marías, Morelos, Mexico. Oral bioassays using healthy P. blanchardi larvae fed with the Mor4.1 isolate showed that this strain was able to cause an antifeeding effect and a significant loss of weight. Mortality was observed for P. blanchardi, P. trichodes, and P. obsoleta in a multidose experiment. The Mor4.1 isolate also caused 100% mortality 24 h after intracoelomic inoculation of the larvae of P. blanchardi, P. ravida, Anomala donovani and the lepidopteran insect Manduca sexta. Oral and injection bioassays were performed with concentrated culture broths of the Mor4.1 isolate to search for disease symptoms and mortality caused by extracellular proteins. The results have shown that Mor4.1 broths produce significant antifeeding effects and mortality. Mor4.1 broths treated with proteinase K lost the ability to cause disease symptoms and mortality, in both the oral and the injection bioassays, suggesting the involvement of toxic proteins in the disease. The Mor4.1 isolate was identified as a putative Serratia entomophila Mor4.1 strain based on numerical taxonomy and phylogenetic analyses done with the 16S rRNA gene sequence. The potential of S. entomophila Mor4.1 and its toxins to be used in an integrated pest management program is discussed. PMID:18083879

  9. Comparison of three diagnostic methods for the detection of Toxoplasma gondii in free range chickens.

    PubMed

    Hamidinejat, H; Nabavi, L; Mayahi, M; Ghourbanpoor, M; Pourmehdi Borojeni, M; Norollahi Fard, S; Shokrollahi, M

    2014-09-01

    Detection of Toxoplasma gondii in free range chickens is an indicator of the prevalence and distribution pattern of T. gondii in the environment. For this purpose, serologic assays especially modified agglutination test (MAT) is the main approach in the literature. The main goal of this study was to compare the polymerase chain reaction (PCR) based on amplification of first internal transcribed spacer (ITS-1) of ribosomal DNA gene, ELISA, and MAT to demonstrate T. gondii infection in free range chicken. A total of 106 adult free - range chickens were killed. Blood, whole heart and brain samples were taken. Sera were examined for the presence of T. gondii antibodies by ELISA and MAT as well. Selected tissues were used for PCR and bioassay in mice. The results revealed that 48.11%, 51.89%, 46.23% and 27.36% of chickens were positive in ELISA, MAT, PCR and bioassay in mice respectively. Good correlation between the results of PCR, ELISA and MAT were detected, but not with bioassay in mice. Compared with PCR, the sensitivity and specificity of ELISA were 92.16% and 96.36% respectively and also for MAT, the sensitivity was 81.81% and the specificity was 92.15%. The specific diagnosis of T. gondii infection in chickens is central to a better understanding of the epidemiology and dynamics of transmission among the various host population and is particularly important for planning effective optimal prevention and control programs. Our data in the present study demonstrated that PCR, ELISA and the MAT are helpful and precise methods to detect T. gondii in naturally infected free-range chickens.

  10. INTRODUCTION AND STUDY DESIGN

    EPA Science Inventory

    Under the sponsorship of the UNEP/ILO/IPCS, 17 laboratories from diverse regions of the world participated in evaluating the utility of four plant bioassays for detecting genetic hazards of environmental chemicals. he bioassays included in this collaborative study were Arabidopsi...

  11. Bioassay-Directed Fractionation of Diesel and Biodiesel Emissions

    EPA Science Inventory

    Biofuels are being developed as alternatives to petroleum-derived products, but published research is contradictory regarding the mutagenic activity of such emissions relative to those from petroleum diesel. We performed bioassay-directed fractionation and analyzed the polycyclic...

  12. Determination of ametryn herbicide by bioassay and gas chromatography-mass spectrometry in analysis of residues in drinking water.

    PubMed

    Queiroz, R H; Lanchote, V L; Bonato, P S; Tozato, E; de Carvalho, D; Gomes, M A; Cerdeira, A L

    1999-06-01

    A simple, rapid and quantitative bioassay method was compared to a gas chromatography/mass spectrometry (GC/MS) procedure for the analysis of ametryn in surface and groundwater. This method was based on the activity of ametryn in inhibiting the growth of the primary root and shoot of germinating letuce, Lactuca sativa L. seed. The procedure was sensitive to 0.01 microgram/l and was applicable from this concentration up to 0.6 microgram/l. Initial surface sterilization of the seed, selection of pregerminated seed of certain root lengths and special equipment are not necessary. So, we concluded that the sensitivity of the bioassay method is compatible with the chromatographic method (GC-MS). However, the study of the correlation between methods suggests that the bioassay should be used only as a screening technique for the evaluation of ametryn residues in water.

  13. A rapid and inexpensive bioassay to evaluate the decontamination of organophosphates.

    PubMed

    Claborn, David M; Martin-Brown, Skylar A; Sagar, Sanjay Gupta; Durham, Paul

    2012-01-01

    An inexpensive and rapid bioassay using adult red flour beetles was developed for use in assessing the decontamination of environments containing organophosphates and related chemicals. A decontamination protocol was developed which demonstrated that 2 to 3 applications of 5% bleach solution were required to obtain nearly complete decontamination of malathion. The bioassay was also used to screen common household cleaners as potential decontaminating agents, but only 5% bleach was effective at improving survival of insects on steel plates treated with 25% malathion. A toxic degradation product (malaoxon) was detected using gas chromatography/mass spectrophotometry; this toxin affected the decontamination efficacy and resulted in continued toxicity to the beetles until subsequent decontaminations. The bioassay provides evidence to support the use of red flour beetles as a sensitive, less expensive method for determining safety levels of environments contaminated with malathion and other toxins, and may have application in the study of chemical warfare agents.

  14. Real-Time Continuous Identification of Greenhouse Plant Pathogens Based on Recyclable Microfluidic Bioassay System.

    PubMed

    Qu, Xiangmeng; Li, Min; Zhang, Hongbo; Lin, Chenglie; Wang, Fei; Xiao, Mingshu; Zhou, Yi; Shi, Jiye; Aldalbahi, Ali; Pei, Hao; Chen, Hong; Li, Li

    2017-09-20

    The development of a real-time continuous analytical platform for the pathogen detection is of great scientific importance for achieving better disease control and prevention. In this work, we report a rapid and recyclable microfluidic bioassay system constructed from oligonucleotide arrays for selective and sensitive continuous identification of DNA targets of fungal pathogens. We employ the thermal denaturation method to effectively regenerate the oligonucleotide arrays for multiple sample detection, which could considerably reduce the screening effort and costs. The combination of thermal denaturation and laser-induced fluorescence detection technique enables real-time continuous identification of multiple samples (<10 min per sample). As a proof of concept, we have demonstrated that two DNA targets of fungal pathogens (Botrytis cinerea and Didymella bryoniae) can be sequentially analyzed using our rapid microfluidic bioassay system, which provides a new paradigm in the design of microfluidic bioassay system and will be valuable for chemical and biomedical analysis.

  15. Bioassay, isolation and studies on the mechanism of action of neurite extension factor

    NASA Technical Reports Server (NTRS)

    Kligman, D.

    1984-01-01

    The identification and purification of molecules active in promoting neurite outgrowth requires a sensitive reproducible bioassay. A quantitative bioassay was utilized to purify a neurite extension factor (NEF) based on counting the number of phase bright neurons with processes at least equal to one cell body diameter after 20 hrs. in culture is defined, serum free medium. Using a combination of heat treatment DEAE cellulose chromatography and gel filtration, an acidic protein of M sub r = 75,000 was highly purified. Upon reduction, it yields subunits of M sub r = 37,000. Purified fractions are active half maximally at 100 ng/ml in inducing neurite outgrowth in this bioassay. Currently, monoclonal antibodies to NEF are being produced. Female Balb C mice were immunized with the antigen and fusions with mouse myeloma cells will be performed to yield hybridoma cells.

  16. Requirements for radiation emergency urine bioassay techniques for the public and first responders.

    PubMed

    Li, Chunsheng; Vlahovich, Slavica; Dai, Xiongxin; Richardson, Richard B; Daka, Joseph N; Kramer, Gary H

    2010-11-01

    Following a radiation emergency, the affected public and the first responders may need to be quickly assessed for internal contamination by the radionuclides involved. Urine bioassay is one of the most commonly used methods for assessing radionuclide intake and radiation dose. This paper attempts to derive the sensitivity requirements (from inhalation exposure) for the urine bioassay techniques for the top 10 high-risk radionuclides that might be used in a terrorist attack. The requirements are based on a proposed reference dose to adults of 0.1 Sv (CED, committed effective dose). In addition, requirements related to sample turnaround time and field deployability of the assay techniques are also discussed. A review of currently available assay techniques summarized in this paper reveals that method development for ²⁴¹Am, ²²⁶Ra, ²³⁸Pu, and ⁹⁰Sr urine bioassay is needed.

  17. Comparison of liquid chromatographic and bioassay procedures for determining depletion of intramuscularly injected tylosin.

    PubMed

    Moats, W A; Harris, E W; Steele, N C

    1985-01-01

    Crossbred pigs weighing 80-110 kg were injected intramuscularly in the ham with 8.8 mg/kg tylosin. Animals were slaughtered in groups of 3 at intervals of 4 h, and 1, 2, 4, and 8 days after injection, and samples of blood, injected muscle, uninjected muscle, liver, and kidney were analyzed by liquid chromatography (LC) and by bioassay using Sarcina lutea as the test organism. The LC method was far more sensitive with a detection limit of less than 0.1 ppm, while the detection limit by bioassay was about 0.5 ppm in tissue. Results by bioassay and LC sometimes differed considerably for tissue samples. Residues in all tissues were below the tolerance limit of 0.2 ppm at 24 h, except in the injected muscle in one animal. Residues were not detected in any tissue of any animal at 48 h after treatment.

  18. Sampling method, storage and pretreatment of sediment affect AVS concentrations with consequences for bioassay responses.

    PubMed

    De Lange, H J; Van Griethuysen, C; Koelmans, A A

    2008-01-01

    Sediment treatment and sediment storage may alter sediment toxicity, and consequently biotic response. Purpose of our study was to combine these three aspects (treatment-toxicity-biotic response) in one integrated approach. We used Acid Volatile Sulfide (AVS) concentrations as a proxy of the disturbance of the sediment. AVS and Simultaneously Extracted Metal (SEM) concentrations were compared to bioassay responses with the freshwater benthic macroinvertebrate Asellus aquaticus. Storage conditions and sediment treatment affected AVS but not SEM levels. AVS can be used as a proxy for sediment disturbance. The best way to pretreat the sediment for use in a bioassay in order to maintain initial AVS conditions was to sample the sediment with an Ekman grab, immediately store it in a jar without headspace, and freeze it as soon as possible. In a survey using seven different sediments, bioassay responses of A. aquaticus were correlated with SEM and AVS characteristics.

  19. Reliability database development for use with an object-oriented fault tree evaluation program

    NASA Technical Reports Server (NTRS)

    Heger, A. Sharif; Harringtton, Robert J.; Koen, Billy V.; Patterson-Hine, F. Ann

    1989-01-01

    A description is given of the development of a fault-tree analysis method using object-oriented programming. In addition, the authors discuss the programs that have been developed or are under development to connect a fault-tree analysis routine to a reliability database. To assess the performance of the routines, a relational database simulating one of the nuclear power industry databases has been constructed. For a realistic assessment of the results of this project, the use of one of existing nuclear power reliability databases is planned.

  20. Software development to support sensor control of robot arc welding

    NASA Technical Reports Server (NTRS)

    Silas, F. R., Jr.

    1986-01-01

    The development of software for a Digital Equipment Corporation MINC-23 Laboratory Computer to provide functions of a workcell host computer for Space Shuttle Main Engine (SSME) robotic welding is documented. Routines were written to transfer robot programs between the MINC and an Advanced Robotic Cyro 750 welding robot. Other routines provide advanced program editing features while additional software allows communicatin with a remote computer aided design system. Access to special robot functions were provided to allow advanced control of weld seam tracking and process control for future development programs.

  1. Integrated Digital Flight Control System for the Space Shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The objectives of the integrated digital flight control system (DFCS) is to provide rotational and translational control of the space shuttle orbiter in all phases of flight: from launch ascent through orbit to entry and touchdown, and during powered horizontal flights. The program provides a versatile control system structure while maintaining uniform communications with other programs, sensors, and control effectors by using an executive routine/functional subroutine format. The program reads all external variables at a single point, copies them into its dedicated storage, and then calls the required subroutines in the proper sequence. As a result, the flight control program is largely independent of other programs in the computer complex and is equally insensitive to characteristics of the processor configuration. The integrated structure is described of the control system and the DFCS executive routine which embodies that structure. The input and output, including jet selection are included. Specific estimation and control algorithm are shown for the various mission phases: cruise (including horizontal powered flight), entry, on-orbit, and boost. Attitude maneuver routines that interface with the DFCS are included.

  2. In situ assessment of pesticide genotoxicity in an integrated pest management program: II. Maize waxy mutation assay.

    PubMed

    Rodrigues, G S; Pimentel, D; Weinstein, L H

    1998-02-13

    The mutagenicity induced by pesticides applied in an integrated pest management (IPM) program was evaluated in situ with the maize forward waxy mutation bioassay. Three pesticide application rates were prescribed as follows: (1) Low--no field pesticide spray; (2) Medium--IPM test rate: banded cyanazine plus metolachlor (2.7 kg a.i. and 2.3 l a.i./ha of herbicides, respectively); and (3) High--a preventative pesticide application program: broadcast cyanazine plus metolachlor (same application rates as above) plus chlorpyrifos (1 kg a.i./ha of insecticide). In general, there was no significant reduction in the genotoxic effects from the high to the medium treatment levels of the IPM program. This suggests that the reduction in pesticide application rates attained with the implementation of the proposed IPM program was not sufficient to abate the genotoxicity of the pesticides. The results indicate that replacing genotoxic compounds may be the only effective remediation measure if concern about environmental mutagenesis were to result in changes in agricultural management.

  3. The impacts of using community health volunteers to coach medication safety behaviors among rural elders with chronic illnesses.

    PubMed

    Wang, Chi-Jane; Fetzer, Susan J; Yang, Yi-Ching; Wang, Jing-Jy

    2013-01-01

    It is a challenge for rural health professionals to promote medication safety among older adults taking multiple medications. A volunteer coaching program to promote medication safety among rural elders with chronic illnesses was designed and evaluated. A community-based interventional study randomly assigned 62 rural elders with at least two chronic illnesses to routine care plus volunteer coaching or routine care alone. The volunteer coaching group received a medication safety program, including a coach and reminders by well-trained volunteers, as well as three home visits and five telephone calls over a two-month period. All the subjects received routine medication safety instructions for their chronic illnesses. The program was evaluated using pre- and post-tests of knowledge, attitude and behaviors with regard to medication safety. Results show the volunteer coaching group improved their knowledge of medication safety, but there was no change in attitude after the two-month study period. Moreover, the group demonstrated three improved medication safety behaviors compared to the routine care group. The volunteer coaching program and instructions with pictorial aids can provide a reference for community health professionals who wish to improve the medication safety of chronically ill elders. Copyright © 2013 Mosby, Inc. All rights reserved.

  4. Ada Linear-Algebra Program

    NASA Technical Reports Server (NTRS)

    Klumpp, A. R.; Lawson, C. L.

    1988-01-01

    Routines provided for common scalar, vector, matrix, and quaternion operations. Computer program extends Ada programming language to include linear-algebra capabilities similar to HAS/S programming language. Designed for such avionics applications as software for Space Station.

  5. Genotoxicity of leachates from a landfill using three bioassays.

    PubMed

    Cabrera, G L; Rodriguez, D M

    1999-05-19

    In the city of Queretaro, around 500 tons of solid wastes are produced everyday and are deposited in a landfill. This is the result of social and economic activities of human beings or from their normal physiological functions. As a result of rain, leachates are produced, which, if not handled and treated correctly, may pollute the underground water. Among the bioassays developed for the detection of mutagenicity in environmental pollutants, plant systems have been proven to be sensitive, cheap, and effective. The purpose of this study was to determine the presence of genotoxic agents in the leachates of the landfill of the city using three bioassays: Tradescantia-micronucleus (Trad-MCN), Tradescantia stamen hair mutations (Trad-SHM) and Allium root anaphase aberrations (AL-RAA) and make a comparison of the results in the three assays. Leachates were sampled during both the dry and rainy seasons. Plant cuttings of Tradescantia or the roots of Allium were treated by submerging them in the leachates. Three replicates of each sample were analyzed in each of the three bioassays. As expected the samples of leachates collected during the dry season showed a higher genotoxicity than those collected during the rainy season. In conclusion, there are substances present in the leachates capable of inducing genotoxicity in the plant assays. On the other hand, the plant assays showed different degrees of sensitivity: the more sensitive was the Trad-MCN bioassay and the less sensitive the Trad-SHM assay. Therefore, when analyzing environmental pollutants it is recommended to use a battery of bioassays. Copyright 1999 Elsevier Science B.V.

  6. In vitro activity of ten essential oils against Sarcoptes scabiei.

    PubMed

    Fang, Fang; Candy, Kerdalidec; Melloul, Elise; Bernigaud, Charlotte; Chai, Ling; Darmon, Céline; Durand, Rémy; Botterel, Françoise; Chosidow, Olivier; Izri, Arezki; Huang, Weiyi; Guillot, Jacques

    2016-11-22

    The development of alternative approaches in ectoparasite management is currently required. Essential oils have been demonstrated to exhibit fumigant and topical toxicity to a number of arthropods. The aim of the present study was to assess the potential efficacy of ten essential oils against Sarcoptes scabiei. The major chemical components of the oils were identified by GC-MS analysis. Contact and fumigation bioassays were performed on Sarcoptes mites collected from experimentally infected pigs. For contact bioassays, essential oils were diluted with paraffin to get concentrations at 10, 5, and even 1% for the most efficient ones. The mites were inspected under a stereomicroscope 10, 20, 30, 40, 50, 60, 90, 120, 150, and 180min after contact. For fumigation bioassay, a filter paper was treated with 100 μL of the pure essential oil. The mites were inspected under a stereomicroscope for the first 5min, and then every 5min until 1h. Using contact bioassays, 1% clove and palmarosa oil killed all the mites within 20 and 50min, respectively. The oils efficacy order was: clove > palmarosa > geranium > tea tree > lavender > manuka > bitter orange > eucalyptus > Japanese cedar. In fumigation bioassays, the efficacy order was: tea tree > clove > eucalyptus > lavender > palmarosa > geranium > Japanese cedar > bitter orange > manuka. In both bioassays, cade oil showed no activity. Essential oils, especially tea tree, clove, palmarosa, and eucalyptus oils, are potential complementary or alternative products to treat S. scabiei infections in humans or animals, as well as to control the mites in the environment.

  7. Integrating bioassays and analytical chemistry as an improved approach to support safety assessment of food contact materials.

    PubMed

    Veyrand, Julien; Marin-Kuan, Maricel; Bezencon, Claudine; Frank, Nancy; Guérin, Violaine; Koster, Sander; Latado, Hélia; Mollergues, Julie; Patin, Amaury; Piguet, Dominique; Serrant, Patrick; Varela, Jesus; Schilter, Benoît

    2017-10-01

    Food contact materials (FCM) contain chemicals which can migrate into food and result in human exposure. Although it is mandatory to ensure that migration does not endanger human health, there is still no consensus on how to pragmatically assess the safety of FCM since traditional approaches would require extensive toxicological and analytical testing which are expensive and time consuming. Recently, the combination of bioassays, analytical chemistry and risk assessment has been promoted as a new paradigm to identify toxicologically relevant molecules and address safety issues. However, there has been debate on the actual value of bioassays in that framework. In the present work, a FCM anticipated to release the endocrine active chemical 4-nonyphenol (4NP) was used as a model. In a migration study, the leaching of 4NP was confirmed by LC-MS/MS and GC-MS. This was correlated with an increase in both estrogenic and anti-androgenic activities as measured with bioassays. A standard risk assessment indicated that according to the food intake scenario applied, the level of 4NP measured was lower, close or slightly above the acceptable daily intake. Altogether these results show that bioassays could reveal the presence of an endocrine active chemical in a real-case FCM migration study. The levels reported were relevant for safety assessment. In addition, this work also highlighted that bioactivity measured in migrate does not necessarily represent a safety issue. In conclusion, together with analytics, bioassays contribute to identify toxicologically relevant molecules leaching from FCM and enable improved safety assessment.

  8. Quality of water types in Ukraine evaluated by WaterTox bioassays.

    PubMed

    Arkhipchuk, V V; Malinovskaya, M V

    2002-01-01

    The quality of river, ground-, and tap water was analyzed using the basic set of WaterTox bioassays [Daphnia (Daphnia magna), Hydra (Hydra attenuata), and lettuce (Lactuca sativa)] as well as two additional bioassays, onion (Allium cepa) and microalga (Selenastrum gracile). Samples of these waters were also concentrated fivefold using a solid-phase procedure. The results of the Daphnia and Hydra bioassays showed that the winter and spring concentrated and nonconcentrated samples from the Dnieper and Desna rivers, the main water supply sources for Kiev, were nontoxic. In spring, after concentration, the two river samples brought about the same relative decrease in the lettuce root length (by 35%, p < 0.001), where the Desna River sample considerably reduced (by 79.1%, p < 0.001) the number of microalga cells. Samples of groundwater from countryside wells studied in autumn in several villages of the Kiev region were toxic mainly to Hydra (sublethal effects were found in 11%-78%) and lettuce (the root length decreased 15%-56%). Studies of tap water samples from two of the largest cities of Ukraine, Kiev and Kharkiv, were found to be nontoxic to both plants, lettuce and onion, but showed increased sublethal and lethal effects on both animals, Daphnia and Hydra, as well as a reduced number of microalgae. Different bioassays were sensitive to varying degrees to different water types. This reinforces the necessity of using sets of bioassays in toxicity evaluation. In general, all the tested water samples demonstrated some toxicity. These data suggest that drinking water quality in Ukraine needs improvement. Copyright 2002 Wiley Periodicals, Inc.

  9. The use of genetically modified mice in cancer risk assessment: Challenges and limitations*

    PubMed Central

    Eastmond, David A.; Vulimiri, Suryanarayana V.; French, John E.; Sonawane, Babasaheb

    2015-01-01

    The use of genetically modified (GM) mice to assess carcinogenicity is playing an increasingly important role in the safety evaluation of chemicals. While progress has been made in developing and evaluating mouse models such as the Trp53+/−, Tg.AC and the rasH2, the suitability of these models as replacements for the conventional rodent cancer bioassay and for assessing human health risks remains uncertain. The objective of this research was to evaluate the use of accelerated cancer bioassays with GM mice for assessing the potential health risks associated with exposure to carcinogenic agents. We compared the published results from the GM bioassays to those obtained in the National Toxicology Program’s conventional chronic mouse bioassay for their potential use in risk assessment. Our analysis indicates that the GM models are less efficient in detecting carcinogenic agents but more consistent in identifying non-carcinogenic agents. We identified several issues of concern related to the design of the accelerated bioassays (e.g., sample size, study duration, genetic stability and reproducibility) as well as pathway-dependency of effects, and different carcinogenic mechanisms operable in GM and non-GM mice. The use of the GM models for dose-response assessment is particularly problematic as these models are, at times, much more or less sensitive than the conventional rodent cancer bioassays. Thus, the existing GM mouse models may be useful for hazard identification, but will be of limited use for dose-response assessment. Hence, caution should be exercised when using GM mouse models to assess the carcinogenic risks of chemicals. PMID:23985072

  10. Do we really need in-situ bioassays?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    In-situ bioassays are needed to validate the results from laboratory testing and to understand biological interactions. Standard laboratory protocols provide reproducible test results, and the precision of those tests can be mathematically defined. Significant correlations between toxic substances and levels of response (bioaccumulation and bioeffects) have also been demonstrated with natural field populations and suggest that the laboratory results can accurately predict field responses. An equal number of studies have shown a lack of correlation between laboratory bioassay results and responses of natural field populations. The best way to validate laboratory results is with manipulative field testing; i.e., in-situ bioassaysmore » with caged organisms. Bioaccumulation in transplanted bivalves has probably been the most frequently used form of an in-situ bioassay. The authors have refined those methods to include synoptic measurements of bioaccumulation and growth. Growth provides an easily-measured bioeffects endpoint and a means of calibrating bioaccumulation. Emphasis has been on minimizing the size range of test animals, repetitive measurements of individuals and standardization of test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Others have developed methods for in-situ bioassays using eggs, larvae, unicellular organisms, crustaceans, benthic invertebrates, bivalves, and fish. In the final analysis, the in-situ approach could be considered as an exposure system where any clinical measurements are possible. The most powerful approach would be to use the same species in laboratory and field experiments with the same endpoints.« less

  11. Bioassays for Evaluating Water Quality-Technical Brief

    EPA Pesticide Factsheets

    Bioassays are a potential solution for assessing complex samples since they screen for total bioactivity for a given pathway or mode of action (MOA), such as estrogen receptor activation, in the samples. EPA has made considerable progress in the developmen

  12. The activity of the pyrrole insecticide chlorfenapyr in mosquito bioassay: towards a more rational testing and screening of non-neurotoxic insecticides for malaria vector control.

    PubMed

    Oxborough, Richard M; N'Guessan, Raphael; Jones, Rebecca; Kitau, Jovin; Ngufor, Corine; Malone, David; Mosha, Franklin W; Rowland, Mark W

    2015-03-24

    The rapid selection of pyrethroid resistance throughout sub-Saharan Africa is a serious threat to malaria vector control. Chlorfenapyr is a pyrrole insecticide which shows no cross resistance to insecticide classes normally used for vector control and is effective on mosquito nets under experimental hut conditions. Unlike neurotoxic insecticides, chlorfenapyr owes its toxicity to disruption of metabolic pathways in mitochondria that enable cellular respiration. A series of experiments explored whether standard World Health Organization (WHO) guidelines for evaluation of long-lasting insecticidal nets, developed through testing of pyrethroid insecticides, are suitable for evaluation of non-neurotoxic insecticides. The efficacy of WHO recommended cone, cylinder and tunnel tests was compared for pyrethroids and chlorfenapyr. To establish bioassay exposure times predictive of insecticide-treated net (ITN) efficacy in experimental hut trials, standard three-minute bioassays of pyrethroid and chlorfenapyr ITNs were compared with longer exposures. Mosquito behaviour and response to chlorfenapyr ITN in bioassays conducted at night were compared to day and across a range of temperatures representative of highland and lowland transmission. Standard three-minute bioassay of chlorfenapyr produced extremely low levels of mortality compared to pyrethroids. Thirty-minute day-time bioassay produced mortality closer to hut efficacy of chlorfenapyr ITN but still fell short of the WHO threshold. Overnight tunnel test with chlorfenapyr produced 100% mortality and exceeded the WHO threshold of 80%. The endogenous circadian activity rhythm of anophelines results in inactivity by day and raised metabolism and flight activity by night. A model which explains improved toxicity of chlorfenapyr ITN when tested at night, and during the day at higher ambient temperature, is that activation of chlorfenapyr and disruption of respiratory pathways is enhanced when the insect is more metabolically and behaviourally active. Testing according to current WHO guidelines is not suitable for certain types of non-neurotoxic insecticide which, although highly effective in field trials, would be overlooked at the screening stage of evaluation through bioassay. Testing methods must be tailored to the characteristics and mode of action of each insecticide class. The WHO tunnel test on night-active anophelines is the most reliable bioassay for identifying the toxicity of novel insecticides.

  13. The quality of clinical maternal and neonatal healthcare - a strategy for identifying 'routine care signal functions'.

    PubMed

    Brenner, Stephan; De Allegri, Manuela; Gabrysch, Sabine; Chinkhumba, Jobiba; Sarker, Malabika; Muula, Adamson S

    2015-01-01

    A variety of clinical process indicators exists to measure the quality of care provided by maternal and neonatal health (MNH) programs. To allow comparison across MNH programs in low- and middle-income countries (LMICs), a core set of essential process indicators is needed. Although such a core set is available for emergency obstetric care (EmOC), the 'EmOC signal functions', a similar approach is currently missing for MNH routine care evaluation. We describe a strategy for identifying core process indicators for routine care and illustrate their usefulness in a field example. We first developed an indicator selection strategy by combining epidemiological and programmatic aspects relevant to MNH in LMICs. We then identified routine care process indicators meeting our selection criteria by reviewing existing quality of care assessment protocols. We grouped these indicators into three categories based on their main function in addressing risk factors of maternal or neonatal complications. We then tested this indicator set in a study assessing MNH quality of clinical care in 33 health facilities in Malawi. Our strategy identified 51 routine care processes: 23 related to initial patient risk assessment, 17 to risk monitoring, 11 to risk prevention. During the clinical performance assessment a total of 82 cases were observed. Birth attendants' adherence to clinical standards was lowest in relation to risk monitoring processes. In relation to major complications, routine care processes addressing fetal and newborn distress were performed relatively consistently, but there were major gaps in the performance of routine care processes addressing bleeding, infection, and pre-eclampsia risks. The identified set of process indicators could identify major gaps in the quality of obstetric and neonatal care provided during the intra- and immediate postpartum period. We hope our suggested indicators for essential routine care processes will contribute to streamlining MNH program evaluations in LMICs.

  14. The Quality of Clinical Maternal and Neonatal Healthcare – A Strategy for Identifying ‘Routine Care Signal Functions’

    PubMed Central

    Brenner, Stephan; De Allegri, Manuela; Gabrysch, Sabine; Chinkhumba, Jobiba; Sarker, Malabika; Muula, Adamson S.

    2015-01-01

    Background A variety of clinical process indicators exists to measure the quality of care provided by maternal and neonatal health (MNH) programs. To allow comparison across MNH programs in low- and middle-income countries (LMICs), a core set of essential process indicators is needed. Although such a core set is available for emergency obstetric care (EmOC), the ‘EmOC signal functions’, a similar approach is currently missing for MNH routine care evaluation. We describe a strategy for identifying core process indicators for routine care and illustrate their usefulness in a field example. Methods We first developed an indicator selection strategy by combining epidemiological and programmatic aspects relevant to MNH in LMICs. We then identified routine care process indicators meeting our selection criteria by reviewing existing quality of care assessment protocols. We grouped these indicators into three categories based on their main function in addressing risk factors of maternal or neonatal complications. We then tested this indicator set in a study assessing MNH quality of clinical care in 33 health facilities in Malawi. Results Our strategy identified 51 routine care processes: 23 related to initial patient risk assessment, 17 to risk monitoring, 11 to risk prevention. During the clinical performance assessment a total of 82 cases were observed. Birth attendants’ adherence to clinical standards was lowest in relation to risk monitoring processes. In relation to major complications, routine care processes addressing fetal and newborn distress were performed relatively consistently, but there were major gaps in the performance of routine care processes addressing bleeding, infection, and pre-eclampsia risks. Conclusion The identified set of process indicators could identify major gaps in the quality of obstetric and neonatal care provided during the intra- and immediate postpartum period. We hope our suggested indicators for essential routine care processes will contribute to streamlining MNH program evaluations in LMICs. PMID:25875252

  15. Methodological Considerations for Use of Routine Health Information System Data to Evaluate Malaria Program Impact in an Era of Declining Malaria Transmission

    PubMed Central

    Ashton, Ruth A.; Bennett, Adam; Yukich, Joshua; Bhattarai, Achuyt; Keating, Joseph; Eisele, Thomas P.

    2017-01-01

    Abstract. Coverage of malaria control interventions is increasing dramatically across endemic countries. Evaluating the impact of malaria control programs and specific interventions on health indicators is essential to enable countries to select the most effective and appropriate combination of tools to accelerate progress or proceed toward malaria elimination. When key malaria interventions have been proven effective under controlled settings, further evaluations of the impact of the intervention using randomized approaches may not be appropriate or ethical. Alternatives to randomized controlled trials are therefore required for rigorous evaluation under conditions of routine program delivery. Routine health management information system (HMIS) data are a potentially rich source of data for impact evaluation, but have been underused in impact evaluation due to concerns over internal validity, completeness, and potential bias in estimates of program or intervention impact. A range of methodologies were identified that have been used for impact evaluations with malaria outcome indicators generated from HMIS data. Methods used to maximize internal validity of HMIS data are presented, together with recommendations on reducing bias in impact estimates. Interrupted time series and dose-response analyses are proposed as the strongest quasi-experimental impact evaluation designs for analysis of malaria outcome indicators from routine HMIS data. Interrupted time series analysis compares the outcome trend and level before and after the introduction of an intervention, set of interventions or program. The dose-response national platform approach explores associations between intervention coverage or program intensity and the outcome at a subnational (district or health facility catchment) level. PMID:28990915

  16. Solid rocket booster performance evaluation model. Volume 4: Program listing

    NASA Technical Reports Server (NTRS)

    1974-01-01

    All subprograms or routines associated with the solid rocket booster performance evaluation model are indexed in this computer listing. An alphanumeric list of each routine in the index is provided in a table of contents.

  17. Computer routines for probability distributions, random numbers, and related functions

    USGS Publications Warehouse

    Kirby, W.H.

    1980-01-01

    Use of previously codes and tested subroutines simplifies and speeds up program development and testing. This report presents routines that can be used to calculate various probability distributions and other functions of importance in statistical hydrology. The routines are designed as general-purpose Fortran subroutines and functions to be called from user-written main programs. The probability distributions provided include the beta, chisquare, gamma, Gaussian (normal), Pearson Type III (tables and approximation), and Weibull. Also provided are the distributions of the Grubbs-Beck outlier test, Kolmogorov 's and Smirnov 's D, Student 's t, noncentral t (approximate), and Snedecor F tests. Other mathematical functions include the Bessel function I (subzero), gamma and log-gamma functions, error functions and exponential integral. Auxiliary services include sorting and printer plotting. Random number generators for uniform and normal numbers are provided and may be used with some of the above routines to generate numbers from other distributions. (USGS)

  18. [Neonatal hyperthyroidism in a premature infant born to a mother with Grave's disease].

    PubMed

    Nicaise, C; Gire, C; Brémond, V; Minodier, P; Soula, F; d'Ercole, C; Palix, C

    2000-05-01

    Neonatal thyrotoxicosis is most commonly due to transplacental transfer of maternal thyroid-stimulating hormone receptor antibodies (TRAb). Bioassay of thyrotropin receptor antibodies may help to determine the risk for neonatal hyperthyroidism. Thyrotoxicosis developed in a premature infant born to a mother with Graves' disease, with a low level of TRAb by bioassay. The infant was treated with carbimazole for two months, until TRAb had disappeared. Bioassay TRAb is not always reliable for predicting the development of neonatal hyperthyroidism in infants born to mothers with Graves' disease. Thyroid function should be measured in all these neonates.

  19. Evaluation of Short-Term Bioassays to Predict Functional Impairment. Development of Cardiovascular Bioassays in Laboratory Animals/Directory of Institutions/Individuals.

    DTIC Science & Technology

    1980-10-01

    r AD-VA~ 207 MITRE CORP MCLEAN VA METREK DIV F/A 6 /20EVALUATION OF SNORT-TERM BIOASSAYS TO PREDICT FUNCTIONAL IMPAIR--ETC(U) OCT Al R THOMAS...Dolley Madison Boulevard ColMcLean, Virginia 22102 S 6 1981O OCT 1u Contracting Officer’s Technical Representative: D Mary C. Henry, Ph.D. US ARMY MEDICAL...GV CESO O .RCPETSCTLGNME A EUL midsAŕ ,yALUATION OF ,11ORT-ER IOA SAYS 5 TaWr"W -T REDICT FUNCTIONAL LPIPNXEN Fiavelor WV C 1 , C rdiovascular

  20. Review of Bioassays for Monitoring Fate and Transport ofEstrogenic Endocrine Disrupting Compounds in Water

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    CGCampbell@lbl.gov

    Endocrine disrupting compounds (EDCs) are recognizedcontaminants threatening water quality. Despite efforts in sourceidentification, few strategies exist for characterization or treatment ofthis environmental pollution. Given that there are numerous EDCs that cannegatively affect humans and wildlife, general screening techniques likebioassays and biosensors provide an essential rapid and intensiveanalysis capacity. Commonly applied bioassays include the ELISA and YESassays, but promising technologies include ER-CALUXa, ELRA, Endotecta,RIANA, and IR-bioamplification. Two biosensors, Endotecta and RIANA, arefield portable using non-cellular biological detection strategies.Environmental management of EDCs in water requires integration ofbiosensors and bioassays for monitoring and assessment.

  1. Colloidal crystal beads composed of core-shell particles for multiplex bioassay.

    PubMed

    Xu, Hua; Zhu, Cun; Zhao, Yuanjin; Zhao, Xiangwei; Hu, Jing; Gu, Zhongze

    2009-04-01

    A convenient method was developed to fabricate colloidal crystal beads (CCBs) with tough mechanical strength, which was used as encoded carriers for multiplex bioassay. The latex particles used for the construction of the CCBs were designed with a rigid core PS and a elastomeric shell poly(MMA/EA/MAA), and were prepared via one-step soap-free emulsion polymerization. The as-above-prepared CCBs were thermo-treated to drive the elastomeric shells of adjacent latex particles joining together. It was found that the coalescence of latex particles can greatly improve the mechanical strength of the CCBs for multiplex bioassay.

  2. Soil bioassays as tools for sludge compost quality assessment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Domene, Xavier, E-mail: x.domene@creaf.uab.es; Sola, Laura; Ramirez, Wilson

    2011-03-15

    Composting is a waste management technology that is becoming more widespread as a response to the increasing production of sewage sludge and the pressure for its reuse in soil. In this study, different bioassays (plant germination, earthworm survival, biomass and reproduction, and collembolan survival and reproduction) were assessed for their usefulness in the compost quality assessment. Compost samples, from two different composting plants, were taken along the composting process, which were characterized and submitted to bioassays (plant germination and collembolan and earthworm performance). Results from our study indicate that the noxious effects of some of the compost samples observed inmore » bioassays are related to the low organic matter stability of composts and the enhanced release of decomposition endproducts, with the exception of earthworms, which are favored. Plant germination and collembolan reproduction inhibition was generally associated with uncomposted sludge, while earthworm total biomass and reproduction were enhanced by these materials. On the other hand, earthworm and collembolan survival were unaffected by the degree of composting of the wastes. However, this pattern was clear in one of the composting procedures assessed, but less in the other, where the release of decomposition endproducts was lower due to its higher stability, indicating the sensitivity and usefulness of bioassays for the quality assessment of composts.« less

  3. The Intersection of CMOS Microsystems and Upconversion Nanoparticles for Luminescence Bioimaging and Bioassays

    PubMed Central

    Wei, Liping.; Doughan, Samer.; Han, Yi.; DaCosta, Matthew V.; Krull, Ulrich J.; Ho, Derek.

    2014-01-01

    Organic fluorophores and quantum dots are ubiquitous as contrast agents for bio-imaging and as labels in bioassays to enable the detection of biological targets and processes. Upconversion nanoparticles (UCNPs) offer a different set of opportunities as labels in bioassays and for bioimaging. UCNPs are excited at near-infrared (NIR) wavelengths where biological molecules are optically transparent, and their luminesce in the visible and ultraviolet (UV) wavelength range is suitable for detection using complementary metal-oxide-semiconductor (CMOS) technology. These nanoparticles provide multiple sharp emission bands, long lifetimes, tunable emission, high photostability, and low cytotoxicity, which render them particularly useful for bio-imaging applications and multiplexed bioassays. This paper surveys several key concepts surrounding upconversion nanoparticles and the systems that detect and process the corresponding luminescence signals. The principle of photon upconversion, tuning of emission wavelengths, UCNP bioassays, and UCNP time-resolved techniques are described. Electronic readout systems for signal detection and processing suitable for UCNP luminescence using CMOS technology are discussed. This includes recent progress in miniaturized detectors, integrated spectral sensing, and high-precision time-domain circuits. Emphasis is placed on the physical attributes of UCNPs that map strongly to the technical features that CMOS devices excel in delivering, exploring the interoperability between the two technologies. PMID:25211198

  4. Development and modification of a recombinant cell bioassay to directly detect halogenated and polycyclic aromatic hydrocarbons in serum.

    PubMed

    Ziccardi, M H; Gardner, I A; Denison, M S

    2000-03-01

    Polycyclic and halogenated aromatic hydrocarbons (PAHs/HAHs) are a diverse group of widespread and persistent environmental contaminants that can cause a variety of detrimental effects in vertebrates. As most available methods to detect these contaminants are expensive, labor and time intensive, and require large amounts of tissue for extraction and analysis, several rapid mechanistically based bioassay systems have been developed to detect these chemicals. Here we describe application and optimization of a recently developed recombinant mouse cell bioassay system that responds to both PAHs and HAHs with the rapid induction of firefly luciferase for the detection of these chemicals in whole serum samples. This chemically activated luciferase expression (CALUX) bioassay has been modified to allow rapid (4-h) and direct analysis of small volumes (25-50 microl) of whole serum in a 96-well microtiter plate format without the need for solvent extraction. This bioassay can detect as little as 10 parts per trillion of the most potent HAH, 2,3,7,8-TCDD, and is also sensitive to other HAHs and PAHs. The use of simple procedures corrects for interplate and intraplate variability and the Ah receptor dependence of the induction response is accounted for by use of the antagonist 4-amino-3-methoxyflavone.

  5. Identification of mammalian cell genotoxins in respirable diesel exhaust particles by bioassay-directed chemical analysis.

    PubMed

    Oh, Seung-Min; Chung, Kyu-Hyuck

    2006-03-01

    A bioassay-directed chemical analysis which consists of mammalian cell bioassays (comet assay, CBMN assay and EROD-microbioassay) in conjunction with analytical measurements was performed to identify the most biologically active compounds of the diesel exhaust particulate matters (DEPs) on mutagenic activity. These bioassay systems were suitable to estimate the mammalian genotoxic potentials of pollutants present in low concentrations in limited environmental samples, as is the case with DEPEs. The results from mutagenic assay showed that the aromatic and slightly polar fraction of DEPs induced chromosomal damage and DNA breakage in a non-cytotoxic dose. It was also revealed that indirect-acting mutagens may mainly contribute to the mutagenic effect of aromatic fraction via the enzyme metabolism system. In the aromatic fraction, several indirect-acting mutagenic PAHs such as dibenzo(a,h)anthracene, chrysene, and 1,2-benzanthracene were detected by GC-MS and the complex mixture effect of this fraction was quantified in terms of its biological-TCDD equivalent concentration (bio-TEQ) which was 32.82 bio-TEQ ng/g-DEPs by EROD-microbioassay. Conclusively, we confirmed that indirect-acting mutagens contained in aromatic fraction may be important causatives of the genotoxicity of extracts of DEPs by integrating the results obtained from a mammalian cell bioassay-directed fractionation.

  6. Enhancing the Transition to Kindergarten: A Randomized Trial to Test the Efficacy of the “Stars” Summer Kindergarten Orientation Program

    PubMed Central

    Berlin, Lisa J.; Dunning, Rebecca D.; Dodge, Kenneth A.

    2010-01-01

    This randomized trial tested the efficacy of an intensive, four-week summer program designed to enhance low-income children's transition to kindergarten (n's = 60 program children, 40 controls). Administered in four public schools, the program focused on social competence, pre-literacy and pre-numeracy skills, school routines, and parental involvement. Hierarchical linear modeling indicated that the program significantly improved teachers’ ratings of (a) the transition to the social aspect of kindergarten for girls (but not boys); and (b) the transition to kindergarten routines for the subgroup of children who had the same teacher for kindergarten as for the summer program. Findings are discussed in terms of practices and policies for supporting children's transition to school. PMID:21969767

  7. C-statistic fitting routines: User's manual and reference guide

    NASA Technical Reports Server (NTRS)

    Nousek, John A.; Farwana, Vida

    1991-01-01

    The computer program is discussed which can read several input files and provide a best set of values for the functions provided by the user, using either C-statistic or the chi(exp 2) statistic method. The program consists of one main routine and several functions and subroutines. Detail descriptions of each function and subroutine is presented. A brief description of the C-statistic and the reason for its application is also presented.

  8. Enhancing systematic implementation of skills training modules for persons with schizophrenia: three steps forward and two steps back?

    PubMed

    van Erp, Nicole H J; van Vugt, Maaike; Verhoeven, Dorien; Kroon, Hans

    2009-01-01

    This brief report addresses the systematic implementation of skills training modules for persons with schizophrenia or related disorders in three Dutch mental health agencies. Information on barriers, strategies and integration into routine daily practice was gathered at 0, 12 and 24 months through interviews with managers, program leaders, trainers, practitioners and clients. Overall implementation of the skills training modules for 74% of the persons with schizophrenia or related disorders was not feasible. Implementation was impeded by an incapable program leader, organizational changes, disappointing referrals and loss of trainers. The agencies made important steps forward to integrate the modules into routine daily practice. A reach percentage of 74% in two years time is too ambitious and needs to be adjusted. Systematic integration of the modules into routine daily practice is feasible, but requires solid program management and continuous effort to involve clients and practitioners.

  9. Larvicidal and antifeedant activity of some plant-derived compounds to Lymantria dispar L. (Lepidoptera: Limantriidae).

    PubMed

    Kostić, Miroslav; Popović, Zorica; Brkić, Dejan; Milanović, Slobodan; Sivcev, Ivan; Stanković, Sladjan

    2008-11-01

    Ethanol solutions of essential oil of Ocimum basilicum and its main component, linalool (both isomer forms), all in three concentrations, as well as botanical standard Bioneem (0.5%), were tested for their toxicity and antifeedant activity against the second instar gypsy moth larvae in the laboratory bioassay. The essential oil of O. basilicum was subjected to gas chromatography analysis, and totally 37 compounds were detected, of which linalool was predominantly present. All tested solutions showed low to moderate larvicidal effect in both residual toxicity test and in chronic larval mortality bioassay. Chronic mortality tests showed that obtained mortality was a consequence of starving rather than ingestion of treated leaves. However, antifeedant index achieved by application of tested solutions in feeding choice assay was remarkable. Foliar application of all tested compounds deterred feeding by L2 in the same percent as Bioneem. Antifeedant index was relatively high at all tested treatments (85-94%); moreover, the larval desensitization to repelling volatiles has not occurred after five days of observation. Low toxic and high antifeedant properties make these plant-derived compounds suitable for incorporation in integrated pest management programs, especially in urban environments.

  10. An inventory and evaluation of biological investigations that relate to stream-water quality in the upper Illinois River basin of Illinois, Indiana, and Wisconsin

    USGS Publications Warehouse

    Steffeck, D.W.; Striegl, Robert G.

    1989-01-01

    Results of studies of the aquatic biology of the upper Illinois River basin provide a historical data source from which inferences can be made about changes in the quality of water in the main stem river and its tributaries. The results of biological investigations that have been conducted throughout the basin since 1900 are summarized and their relevance to stream-water-quality assessment is described, particularly their relevance to the upper Illinois River basin pilot project for the National Water Quality Assessment program. Four general categories of biological investigations were identified: Populations and community structure, chemical concentrations in tissue, organism health, and toxicity measurements. Biological investigations were identified by their location in the basin and by their relevance to each general investigation category. The most abundant literature was in the populations and community structure category. Tissue data were limited to polychlorinated biphenyls, organochlorine pesticides, dioxin, and several metals. The most cited measure of organism health was a condition factor for fish that associates body length with weight or body depth. Toxicity measurements included bioassays and the Ames Tests. The bioassays included several testing methods and test organism. (USGS)

  11. Routine human-competitive machine intelligence by means of genetic programming

    NASA Astrophysics Data System (ADS)

    Koza, John R.; Streeter, Matthew J.; Keane, Martin

    2004-01-01

    Genetic programming is a systematic method for getting computers to automatically solve a problem. Genetic programming starts from a high-level statement of what needs to be done and automatically creates a computer program to solve the problem. The paper demonstrates that genetic programming (1) now routinely delivers high-return human-competitive machine intelligence; (2) is an automated invention machine; (3) can automatically create a general solution to a problem in the form of a parameterized topology; and (4) has delivered a progression of qualitatively more substantial results in synchrony with five approximately order-of-magnitude increases in the expenditure of computer time. Recent results involving the automatic synthesis of the topology and sizing of analog electrical circuits and controllers demonstrate these points.

  12. Activity Settings and Daily Routines in Preschool Classrooms: Diverse Experiences in Early Learning Settings for Low-Income Children.

    PubMed

    Fuligni, Allison Sidle; Howes, Carollee; Huang, Yiching; Hong, Sandra Soliday; Lara-Cinisomo, Sandraluz

    2012-06-01

    This paper examines activity settings and daily classroom routines experienced by 3- and 4-year-old low-income children in public center-based preschool programs, private center-based programs, and family child care homes. Two daily routine profiles were identified using a time-sampling coding procedure: a High Free-Choice pattern in which children spent a majority of their day engaged in child-directed free-choice activity settings combined with relatively low amounts of teacher-directed activity, and a Structured-Balanced pattern in which children spent relatively equal proportions of their day engaged in child-directed free-choice activity settings and teacher-directed small- and whole-group activities. Daily routine profiles were associated with program type and curriculum use but not with measures of process quality. Children in Structured-Balanced classrooms had more opportunities to engage in language and literacy and math activities, whereas children in High Free-Choice classrooms had more opportunities for gross motor and fantasy play. Being in a Structured-Balanced classroom was associated with children's language scores but profiles were not associated with measures of children's math reasoning or socio-emotional behavior. Consideration of teachers' structuring of daily routines represents a valuable way to understand nuances in the provision of learning experiences for young children in the context of current views about developmentally appropriate practice and school readiness.

  13. Activity Settings and Daily Routines in Preschool Classrooms: Diverse Experiences in Early Learning Settings for Low-Income Children

    PubMed Central

    Fuligni, Allison Sidle; Howes, Carollee; Huang, Yiching; Hong, Sandra Soliday; Lara-Cinisomo, Sandraluz

    2011-01-01

    This paper examines activity settings and daily classroom routines experienced by 3- and 4-year-old low-income children in public center-based preschool programs, private center-based programs, and family child care homes. Two daily routine profiles were identified using a time-sampling coding procedure: a High Free-Choice pattern in which children spent a majority of their day engaged in child-directed free-choice activity settings combined with relatively low amounts of teacher-directed activity, and a Structured-Balanced pattern in which children spent relatively equal proportions of their day engaged in child-directed free-choice activity settings and teacher-directed small- and whole-group activities. Daily routine profiles were associated with program type and curriculum use but not with measures of process quality. Children in Structured-Balanced classrooms had more opportunities to engage in language and literacy and math activities, whereas children in High Free-Choice classrooms had more opportunities for gross motor and fantasy play. Being in a Structured-Balanced classroom was associated with children’s language scores but profiles were not associated with measures of children’s math reasoning or socio-emotional behavior. Consideration of teachers’ structuring of daily routines represents a valuable way to understand nuances in the provision of learning experiences for young children in the context of current views about developmentally appropriate practice and school readiness. PMID:22665945

  14. USING BIOASSAYS TO EVALUATE THE PERFORMANCE OF RISK MANAGEMENT TECHNIQUES

    EPA Science Inventory

    Often, the performance of risk management techniques is evaluated by measuring the concentrations of the chemials of concern before and after risk management effoprts. However, using bioassays and chemical data provides a more robust understanding of the effectiveness of risk man...

  15. A CONTROLLED BIOASSAY SYSTEM FOR MEASURING TOXICITY OF HEAVY METALS

    EPA Science Inventory

    Biological availability of metal micronutrients and metal toxicity are believed to be dependent on metal oxidation state, complexation, and solubility as well as the physicochemical characteristics of the aqueous phase. Basic design criteria for fish bioassays which are capable o...

  16. Development of Reduced Sediment Volume Test Procedures for the Estuarine Amphipod Leptocheirus plumulosus

    EPA Science Inventory

    The sediment volume requirements of toxicity and bioaccumulation bioassays affect the cost of the assessment related to field collection, transportation, storage, disposal, and labor associated with organism recovery at bioassay termination. Our objective was to assess four redu...

  17. Monitoring changes in bemisia tabaci susceptibility to neonicotinoid insecticides in Arizona and California

    USDA-ARS?s Scientific Manuscript database

    Laboratory bioassays were carried out on field-collected and laboratory strains of Bemisia tabaci to evaluate relative toxicities of four neonicotinoid insecticides: acetamiprid, dinotefuran, imidacloprid and thiamethoxam. Susceptibility to all four neonicotinoids in leaf-uptake bioassays varied co...

  18. Assessment of Fungal Growth in Liquid Cultures and Bioassay of Toxic Products.

    ERIC Educational Resources Information Center

    Isaac, Susan; And Others

    1988-01-01

    Outlined is a procedure for the assessment of fungal growth under different cultural conditions, together with a demonstration of the toxic nature of exudates released from a fungal pathogen during growth in culture, using a simple bioassay. (Author/CW)

  19. Application of Mode of Action Analysis and Human Relevance Framework

    EPA Science Inventory

    Animal bioassays have been used for more than a half century to determine whether pesticides, pharmaceuticals, industrial chemicals, and other products might cause health problems in humans. As such, animal bioassays have become the standard for detecting the potential for adver...

  20. USING BIOASSAYS TO EVALUATE THE PERFORMANCE OF EDC RISK MANAGEMENT METHODS

    EPA Science Inventory

    In Superfund risk management research, the performance of risk management techniques is typically evaluated by measuring "the concentrations of the chemicals of concern before and after risk management efforts. However, using bioassays and chemical data provides a more robust und...

  1. Red clover: An alternative to antibiotic growth promoters?

    USDA-ARS?s Scientific Manuscript database

    A series of experiments were conducted at the Forage-Animal Production Research Unit to discover a growth-promoting natural product from red clover (Trifolium pratense). Previously published work included a bioassay for antimicrobial activity of phytochemicals. The bioassay was used to discover th...

  2. 40 CFR 141.621 - Routine monitoring.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Routine monitoring. 141.621 Section 141.621 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Stage 2 Disinfection Byproducts Requirements § 141...

  3. 40 CFR 141.621 - Routine monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Routine monitoring. 141.621 Section 141.621 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Stage 2 Disinfection Byproducts Requirements § 141...

  4. 40 CFR 141.621 - Routine monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Routine monitoring. 141.621 Section 141.621 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Stage 2 Disinfection Byproducts Requirements § 141...

  5. 40 CFR 141.621 - Routine monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Routine monitoring. 141.621 Section 141.621 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Stage 2 Disinfection Byproducts Requirements § 141...

  6. In Vitro Biologic Activities of the Antimicrobials Triclocarban, Its Analogs, and Triclosan in Bioassay Screens: Receptor-Based Bioassay Screens

    PubMed Central

    Ahn, Ki Chang; Zhao, Bin; Chen, Jiangang; Cherednichenko, Gennady; Sanmarti, Enio; Denison, Michael S.; Lasley, Bill; Pessah, Isaac N.; Kültz, Dietmar; Chang, Daniel P.Y.; Gee, Shirley J.; Hammock, Bruce D.

    2008-01-01

    Background Concerns have been raised about the biological and toxicologic effects of the antimicrobials triclocarban (TCC) and triclosan (TCS) in personal care products. Few studies have evaluated their biological activities in mammalian cells to assess their potential for adverse effects. Objectives In this study, we assessed the activity of TCC, its analogs, and TCS in in vitro nuclear-receptor–responsive and calcium signaling bioassays. Materials and methods We determined the biological activities of the compounds in in vitro, cell-based, and nuclear-receptor–responsive bioassays for receptors for aryl hydrocarbon (AhR), estrogen (ER), androgen (AR), and ryanodine (RyR1). Results Some carbanilide compounds, including TCC (1–10 μM), enhanced estradiol (E2)-dependent or testosterone-dependent activation of ER- and AR-responsive gene expression up to 2.5-fold but exhibited little or no agonistic activity alone. Some carbanilides and TCS exhibited weak agonistic and/or antagonistic activity in the AhR-responsive bioassay. TCS exhibited antagonistic activity in both ER- and AR-responsive bioassays. TCS (0.1–10 μM) significantly enhanced the binding of [3H]ryanodine to RyR1 and caused elevation of resting cytosolic [Ca2+] in primary skeletal myotubes, but carbanilides had no effect. Conclusions Carbanilides, including TCC, enhanced hormone-dependent induction of ER- and AR-dependent gene expression but had little agonist activity, suggesting a new mechanism of action of endocrine-disrupting compounds. TCS, structurally similar to noncoplanar ortho-substituted poly-chlorinated biphenyls, exhibited weak AhR activity but interacted with RyR1 and stimulated Ca2+ mobilization. These observations have potential implications for human and animal health. Further investigations are needed into the biological and toxicologic effects of TCC, its analogs, and TCS. PMID:18795164

  7. In situ and laboratory bioassays with Chironomus riparius larvae to assess toxicity of metal contamination in rivers: the relative toxic effect of sediment versus water contamination.

    PubMed

    Faria, Mafalda S; Lopes, Ricardo J; Nogueira, António J A; Soares, Amadeu M V M

    2007-09-01

    We used bioassays employing head capsule width and body length increase of Chironomus riparius larvae as end points to evaluate metal contamination in streams. Bioassays were performed in situ near an abandoned Portuguese goldmine in the spring of 2003 and 2004. Bioassays also were performed under laboratory conditions with water and sediment collected from each stream to verify if laboratory bioassays could detect in situ toxicity and to evaluate the relative contribution of sediment and water to overall toxicity. We used field sediments with control water and control sediments with field water to discriminate between metal contamination in water and sediment. Field water with dry and sieved, organic matter-free, and nontreated sediments was used to determine the toxicity of heavy metals that enter the organism through ingested material. In both in situ and laboratory bioassays, body length increase was significantly inhibited by metal contamination, whereas head capsule width was not affected. Body length increase was more affected by contaminated sediment compared to contaminated water. The lowest-effect level of heavy metals was observed in the dry and sieved sediment that prevented ingestion of sediment particles by larvae. These results suggest that body length increase of C. riparius larvae can be used to indicate the impact of metal contamination in rivers. Chironomus riparius larvae are more affected by heavy metals that enter the organism through ingested sediment than by heavy metals dissolved in the water column. Nevertheless, several factors, such as the particle size and organic matter of sediment, must be taken into account.

  8. Effects of wind speed on aerosol spray penetration in adult mosquito bioassay cages.

    PubMed

    Hoffmann, W Clint; Fritz, Bradley K; Farooq, Muhammad; Cooperband, Miriam F

    2008-09-01

    Bioassay cages are commonly used to assess efficacy of insecticides against adult mosquitoes in the field. To correlate adult mortality readings to insecticidal efficacy and/or spray application parameters properly, it is important to know how the cage used in the bioassay interacts with the spray cloud containing the applied insecticide. This study compared the size of droplets, wind speed, and amount of spray material penetrating cages and outside of cages in a wind tunnel at different wind speeds. Two bioassay cages, Center for Medical, Agricultural and Veterinary Entomology (CMAVE) and Circle, were evaluated. The screen materials used on these cages reduced the size of droplets, wind speed, and amount of spray material inside the cages as compared to the spray cloud and wind velocity outside of the cages. When the wind speed in the dispersion tunnel was set at 0.6 m/sec (1.3 mph), the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.045 m/sec (0.10 mph) and 0.075 m/sec (0.17 mph), respectively. At air velocities of 2.2 m/sec (4.9 mph) in the dispersion tunnel, the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.83 m/sec (1.86 mph) and 0.71 m/sec (1.59 mph), respectively. Consequently, there was a consistent 50-70% reduction of spray material penetrating the cages compared to the spray cloud that approached the cages. These results provide a better understanding of the impact of wind speed, cage design, and construction on ultra-low-volume spray droplets.

  9. Management applications for thermal IR imagery of lake processes

    NASA Technical Reports Server (NTRS)

    Whipple, J. M.; Haynes, R. B.

    1971-01-01

    A thermal infrared scanning program was conducted in the Lake Ontario Basin region in an effort to determine: (1) limonologic data that could be collected by remote sensing techniques, and (2) local interest in and routine use of such data in water management programs. Difficulties encountered in the development of an infrared survey program in New York suggest that some of the major obstacles to acceptance of remotely sensed data for routine use are factors of psychology rather than technology. Also, terminology used should suit the measurement technique in order to encourage acceptance of the surface thermal data obtained.

  10. Computing Lives And Reliabilities Of Turboprop Transmissions

    NASA Technical Reports Server (NTRS)

    Coy, J. J.; Savage, M.; Radil, K. C.; Lewicki, D. G.

    1991-01-01

    Computer program PSHFT calculates lifetimes of variety of aircraft transmissions. Consists of main program, series of subroutines applying to specific configurations, generic subroutines for analysis of properties of components, subroutines for analysis of system, and common block. Main program selects routines used in analysis and causes them to operate in desired sequence. Series of configuration-specific subroutines put in configuration data, perform force and life analyses for components (with help of generic component-property-analysis subroutines), fill property array, call up system-analysis routines, and finally print out results of analysis for system and components. Written in FORTRAN 77(IV).

  11. ALOHA: Automatic libraries of helicity amplitudes for Feynman diagram computations

    NASA Astrophysics Data System (ADS)

    de Aquino, Priscila; Link, William; Maltoni, Fabio; Mattelaer, Olivier; Stelzer, Tim

    2012-10-01

    We present an application that automatically writes the HELAS (HELicity Amplitude Subroutines) library corresponding to the Feynman rules of any quantum field theory Lagrangian. The code is written in Python and takes the Universal FeynRules Output (UFO) as an input. From this input it produces the complete set of routines, wave-functions and amplitudes, that are needed for the computation of Feynman diagrams at leading as well as at higher orders. The representation is language independent and currently it can output routines in Fortran, C++, and Python. A few sample applications implemented in the MADGRAPH 5 framework are presented. Program summary Program title: ALOHA Catalogue identifier: AEMS_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMS_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: http://www.opensource.org/licenses/UoI-NCSA.php No. of lines in distributed program, including test data, etc.: 6094320 No. of bytes in distributed program, including test data, etc.: 7479819 Distribution format: tar.gz Programming language: Python2.6 Computer: 32/64 bit Operating system: Linux/Mac/Windows RAM: 512 Mbytes Classification: 4.4, 11.6 Nature of problem: An effcient numerical evaluation of a squared matrix element can be done with the help of the helicity routines implemented in the HELAS library [1]. This static library contains a limited number of helicity functions and is therefore not always able to provide the needed routine in the presence of an arbitrary interaction. This program provides a way to automatically create the corresponding routines for any given model. Solution method: ALOHA takes the Feynman rules associated to the vertex obtained from the model information (in the UFO format [2]), and multiplies it by the different wavefunctions or propagators. As a result the analytical expression of the helicity routines is obtained. Subsequently, this expression is automatically written in the requested language (Python, Fortran or C++) Restrictions: The allowed fields are currently spin 0, 1/2, 1 and 2, and the propagators of these particles are canonical. Running time: A few seconds for the SM and the MSSM, and up to a few minutes for models with spin 2 particles. References: [1] Murayama, H. and Watanabe, I. and Hagiwara, K., HELAS: HELicity Amplitude Subroutines for Feynman diagram evaluations, KEK-91-11, (1992) http://www-lib.kek.jp/cgi-bin/img_index?199124011 [2] C. Degrande, C. Duhr, B. Fuks, D. Grellscheid, O. Mattelaer, et al., UFO— The Universal FeynRules Output, Comput. Phys. Commun. 183 (2012) 1201-1214. arXiv:1108.2040, doi:10.1016/j.cpc.2012.01.022.

  12. GASPLOT - A computer graphics program that draws a variety of thermophysical property charts

    NASA Technical Reports Server (NTRS)

    Trivisonno, R. J.; Hendricks, R. C.

    1977-01-01

    A FORTRAN V computer program, written for the UNIVAC 1100 series, is used to draw a variety of precision thermophysical property charts on the Calcomp plotter. In addition to the program (GASPLOT), which requires (15 160) sub 10 storages, a thermophysical properties routine needed to produce plots. The program is designed so that any two of the state variables, the derived variables, or the transport variables may be plotted as the ordinate - abscissa pair with as many as five parametric variables. The parameters may be temperature, pressure, density, enthalpy, and entropy. Each parameter may have as many a 49 values, and the range of the variables is limited only by the thermophysical properties routine.

  13. As-Built documentation of programs to implement the Robertson and Doraiswamy/Thompson models

    NASA Technical Reports Server (NTRS)

    Valenziano, D. J. (Principal Investigator)

    1981-01-01

    The software which implements two spring wheat phenology models is described. The main program routines for the Doraiswamy/Thompson crop phenology model and the basic Robertson crop phenology model are DTMAIN and BRMAIN. These routines read meteorological data files and coefficient files, accept the planting date information and other information from the user, and initiate processing. Daily processing for the basic Robertson program consists only of calculation of the basic Robertson increment of crop development. Additional processing in the Doraiswamy/Thompson program includes the calculation of a moisture stress index and correction of the basic increment of development. Output for both consists of listings of the daily results.

  14. What have we learned on costs and financing of routine immunization from the comprehensive multi-year plans in GAVI eligible countries?

    PubMed

    Brenzel, Logan

    2015-05-07

    Immunization is one of the most cost-effective health interventions, but as countries introduce new vaccines and scale-up immunization coverage, costs will likely increase. This paper updates estimates of immunization costs and financing based on information from comprehensive multi-year plans (cMYPs) from GAVI-eligible countries during a period when countries planned to introduce a range of new vaccines (2008-2016). The analysis database included information from baseline and 5-year projection years for each country cMYP, resulting in a total sample size of 243 observations. Two-thirds were from African countries. Cost data included personnel, vaccine, injection, transport, training, maintenance, cold chain and other capital investments. Financing from government and external sources was evaluated. All estimates were converted to 2010 US Dollars. Statistical analysis was performed using STATA, and results were population-weighted. Results pertain to country planning estimates. Average annual routine immunization cost was $62 million. Vaccines continued to be the major cost driver (51%) followed by immunization-specific personnel costs (22%). Non-vaccine delivery costs accounted for almost half of routine program costs (44%). Routine delivery cost per dose averaged $0.61 and the delivery cost per infant was $10. The cost per DTP3 vaccinated child was $27. Routine program costs increased with each new vaccine introduced. Costs accounted for 5% of government health expenditures. Governments accounted for 67% of financing. Total and average costs of routine immunization programs are rising as coverage rates increase and new vaccines are introduced. The cost of delivering vaccines is nearly equivalent to the cost of vaccines. Governments are financing greater proportions of the immunization program but there may be limits in resource scarce countries. Price reductions for new vaccines will help reduce costs and the burden of financing. Strategies to improve efficiency in service delivery should be pursued. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. IN SITU BIOASSAY CHAMBER FOR ASSESSMENT OF SEDIMENT TOXICITY AND BIOACCUMULATION USING BENTHIC INVERTEBRATES

    EPA Science Inventory

    In this study, we describe the construction of a simple, inexpensive bioassay chamber for testing sediment toxicity (survival and growth) and bioaccumulation under field conditions using the midge Chironomus tentans and the oligochaete Lumbriculus variegatus. The test chamber is ...

  16. An Estuarine Fish Bioassay for Sensitive Biomonitoring of Oil-related Contamination

    EPA Science Inventory

    An embryonic and larval bioassay using the estuarine fish, Fundulus heteroclitus, was modified for the rapid detection of bioavailable compounds that act through the aryl hydrocarbon receptor (AhR). The early development of fishes is particularly sensitive to AhR agonists, such ...

  17. Bioassay techniques for detecting root leakage of auxinic herbicides

    USDA-ARS?s Scientific Manuscript database

    Biological assay (bioassay) techniques are a simple way to determine the presence of herbicides in soil or other potting media. Understanding the fate of herbicides after absorption is important when guidelines for use are developed. Greenhouse studies were conducted with the herbicide aminocyclopyr...

  18. COMPARATIVE POTENCY OF COMPLEX MIXTURES: USE OF SHORT-TERM GENETIC BIOASSAYS IN CANCER RISK ASSESSMENT

    EPA Science Inventory

    The primary problem regarding the introduction of new energy sources is whether they will alter the mutagenicity, carcinogenicity and potential human cancer risk from combustion emissions. New risk assessment methodologies utilizing data from short-term bioassays, therefore, are ...

  19. STRESS ETHYLENE: A BIOASSAY FOR RHIZOSPHERE-APPLIED PHYTOTOXICANTS

    EPA Science Inventory

    A bioassay for rhizosphere-applied phytotoxicants was developed and evaluated with a broad range of chemicals. Test substances were applied to the rhizosphere of whole, intact bush bean plants (Phaseolus vulgaris L. cv. Bush Blue Lake 290) grown in a solid support medium and the ...

  20. Investigation of animal and algal bioassays for reliable saxitoxin ecotoxicity and cytotoxicity risk evaluation.

    PubMed

    Perreault, François; Matias, Marcelo Seleme; Melegari, Silvia Pedroso; Pinto, Catia Regina Silva de Carvalho; Creppy, Edmond Ekué; Popovic, Radovan; Matias, William Gerson

    2011-05-01

    Contamination of water bodies by saxitoxin can result in various toxic effects in aquatic organisms. Saxitoxin contamination has also been shown to be a threat to human health in several reported cases, even resulting in death. In this study, we evaluated the sensitivity of animal (Neuro-2A) and algal (Chlamydomonas reinhardtii) bioassays to saxitoxin effect. Neuro-2A cells were found to be sensitive to saxitoxin, as shown by a 24 h EC50 value of 1.5 nM, which was obtained using a cell viability assay. Conversely, no saxitoxin effect was found in any of the algal biomarkers evaluated, for the concentration range tested (2-128 nM). These results indicate that saxitoxin may induce toxic effects in animal and human populations at concentrations where phytoplankton communities are not affected. Therefore, when evaluating STX risk of toxicity, algal bioassays do not appear to be reliable indicators and should always be conducted in combination with animal bioassays. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Latex agglutination inhibition card test for gentamicin assay: clinical evaluation and comparison with radioimmunoassay and bioassay.

    PubMed Central

    Standiford, H C; Bernstein, D; Nipper, H C; Caplan, E; Tatem, B; Hall, J S; Reynolds, J

    1981-01-01

    Gentamicin levels were determined in 100 serum specimens by a new latex agglutination inhibition card test, a radioimmunoassay (RIA), and a bioassay. Correlation coefficients determined by linear regression analysis demonstrated that the levels obtained by the latex agglutination inhibition card test had a high degree of correlation with the RIA and could be performed much faster and more economically when processing small numbers of specimens. The bioassay had a slightly lower degree of correlation with both the RIA and the latex test and was adversely influenced by concurrently administered antibiotics which could not be eliminated by beta-lactamase. When measuring gentamicin concentrations above 2 micrograms/ml, the coefficient of variation was less than 14% for the latex agglutination assay compared with 15% for the bioassay and 12% for RIA. The latex agglutination inhibition card test is a rapid, accurate, specific, and reproducible method for monitoring gentamicin levels in patients and is particularly applicable for laboratories processing small numbers of specimens. PMID:7247384

  2. Novel bioassay demonstrates attraction of the white potato cyst nematode Globodera pallida (Stone) to non-volatile and volatile host plant cues.

    PubMed

    Farnier, Kevin; Bengtsson, Marie; Becher, Paul G; Witzell, Johanna; Witzgall, Peter; Manduríc, Sanja

    2012-06-01

    Potato cyst nematodes (PCNs) are a major pest of solanaceous crops such as potatoes, tomatoes, and eggplants and have been widely studied over the last 30 years, with the majority of earlier studies focusing on the identification of natural hatching factors. As a novel approach, we focused instead on chemicals involved in nematode orientation towards its host plant. A new dual choice sand bioassay was designed to study nematode responses to potato root exudates (PRE). This bioassay, conducted together with a traditional hatching bioassay, showed that biologically active compounds that induce both hatching and attraction of PCNs can be collected by water extraction of incised potato roots. Furthermore, our results demonstrated that PCN also were attracted by potato root volatiles. Further work is needed to fully understand how PCNs use host plant chemical cues to orientate towards hosts. Nevertheless, the simple attraction assay used in this study provides an important tool for the identification of host-emitted attractants.

  3. Current and emerging challenges in toxicopathology: Carcinogenic threshold of phenobarbital and proof of arsenic carcinogenicity using rat medium-term bioassays for carcinogens

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fukushima, Shoji; Morimura, Keiichirou; Wanibuchi, Hideki

    2005-09-01

    For the last 25 years, Prof. Nobuyuki Ito and his laboratory have focused on the development of liver medium-term bioassay system for detection of carcinogens in F344 rats utilizing glutathione S-transferase placental form (GST-P)-positive foci as an end point marker. In this presentation, the outline and samples of medium-term bioassay systems were described. Furthermore, our data demonstrated the presence of a threshold for the non-genotoxic carcinogen, phenobarbital (PB), and the lack of linearity in the low-dose area of the dose-response curve, providing evidence for hormesis. In addition, the establishment and applications of multiorgan carcinogenicity bioassay (DMBDD model), used for themore » examination of the carcinogenicity of genotoxic and non-genotoxic chemicals, are discussed. Dimethylarsinic acid, one of organic arsenics, was found to be carcinogenic in rat bladder using DMBDD model and carcinogenicity test.« less

  4. Methodology for the ecotoxicological evaluation of areas polluted by phosphogypsum wastes.

    NASA Astrophysics Data System (ADS)

    Martínez-Sanchez, M. J.; Garcia-Lorenzo, M. L.; Perez-Sirvent, C.; Martinez-Lopez, S.; Hernandez-Cordoba, M.; Bech, J.

    2012-04-01

    In Spain, the production of phosphoric acid, and hence of phosphogypsum, is restricted to a fertilizer industrial site. The residues contain some radionuclides of the U-series and other contaminants. In order to estimate the risk posed by these materials, chemical methods need to be complemented with biological methods. Then, the aim of this study was to develop a battery of bioassays for the ecotoxicological screening of areas polluted by phosphogypsum wastes. Particularly, the toxicity of water samples, sediments and their pore-water extracts was evaluated by using three assays: bacteria, plants and ostracods. The applied bioassays were: the bioluminescence inhibition of Vibrio fischeri in superficial water samples using Microtox® bioassay; the root and shoot elongation inhibition and the mortality of Lepidium sativum, Sorghum saccharatum and Sinapis alba using Phytotoxkit® bioassay; and inhibition of Heterocypris incongruens by way of Ostracodtoxkit®. Proposed methodology allows the identification of contamination sources and non contaminated areas, corresponding to decreasing toxicity values.

  5. Cost of intensive routine control and incremental cost of insecticide-treated curtain deployment in a setting with low Aedes aegypti infestation.

    PubMed

    Baly, Alberto; Toledo, Maria Eugenia; Lambert, Isora; Benítez, Elizabeth; Rodriguez, Karina; Rodriguez, Esther; Vanlerberghe, Veerle; Stuyft, Patrick Van der

    2016-01-01

    Information regarding the cost of implementing insecticide-treated curtains (ITCs) is scarce. Therefore, we evaluated the ITC implementation cost, in addition to the costs of intensive conventional routine activities of the Aedes control program in the city of Guantanamo, Cuba. A cost-analysis study was conducted from the perspective of the Aedes control program, nested in an ITC effectiveness trial, during 2009-2010. Data for this study were obtained from bookkeeping records and activity registers of the Provincial Aedes Control Programme Unit and the account records of the ITC trial. The annual cost of the routine Aedes control program activities was US$16.80 per household (p.h). Among 3,015 households, 6,714 ITCs were distributed. The total average cost per ITC distributed was US$3.42, and 74.3% of this cost was attributed to the cost of purchasing the ITCs. The annualized costs p.h. of ITC implementation was US$3.80. The additional annualized cost for deploying ITCs represented 19% and 48.4% of the total cost of the routine Aedes control and adult-stage Aedes control programs, respectively. The trial did not lead to further reductions in the already relatively low Aedes infestation levels. At current curtain prices, ITC deployment can hardly be considered an efficient option in Guantanamo and other comparable environments.

  6. Improved Air Combat Awareness; with AESA and Next-Generation Signal Processing

    DTIC Science & Technology

    2002-09-01

    competence network Building techniques Software development environment Communication Computer architecture Modeling Real-time programming Radar...memory access, skewed load and store, 3.2 GB/s BW • Performance: 400 MFLOPS Runtime environment Custom runtime routines Driver routines Hardware

  7. Second chronological supplement to the Carcinogenic Potency Database: standardized results of animal bioassays published through December 1984 and by the National Toxicology Program through May 1986.

    PubMed Central

    Gold, L S; Slone, T H; Backman, G M; Magaw, R; Da Costa, M; Lopipero, P; Blumenthal, M; Ames, B N

    1987-01-01

    This paper is the second chronological supplement to the Carcinogenic Potency Database, published earlier in this journal (1,2,4). We report here results of carcinogenesis bioassays published in the general literature between January 1983 and December 1984, and in Technical Reports of the National Cancer Institute/National Toxicology Program between January 1983 and May 1986. This supplement includes results of 525 long-term, chronic experiments of 199 test compounds, and reports the same information about each experiment in the same plot format as the earlier papers: e.g., the species and strain of test animal, the route and duration of compound administration, dose level and other aspects of experimental protocol, histopathology and tumor incidence, TD50 (carcinogenic potency) and its statistical significance, dose response, author's opinion about carcinogenicity, and literature citation. We refer the reader to the 1984 publications for a description of the numerical index of carcinogenic potency (TD50), a guide to the plot of the database, and a discussion of the sources of data, the rationale for the inclusion of particular experiments and particular target sites, and the conventions adopted in summarizing the literature. The three plots of the database are to be used together, since results of experiments published in earlier plots are not repeated. Taken together, the three plots include results for more than 3500 experiments on 975 chemicals. Appendix 14 is an index to all chemicals in the database and indicates which plot(s) each chemical appears in. PMID:3691431

  8. Treatment outcomes for human African Trypanosomiasis in the Democratic Republic of the Congo: analysis of routine program data from the world's largest sleeping sickness control program.

    PubMed

    Hasker, E; Mpanya, A; Makabuza, J; Mbo, F; Lumbala, C; Kumpel, J; Claeys, Y; Kande, V; Ravinetto, R; Menten, J; Lutumba, P; Boelaert, M

    2012-09-01

    To enable the human African trypanosomiasis (HAT) control program of the Democratic Republic of the Congo to generate data on treatment outcomes, an electronic database was developed. The database was piloted in two provinces, Bandundu and Kasai Oriental. In this study, we analysed routine data from the two provinces for the period 2006-2008. Data were extracted from case declaration cards and monthly reports available at national and provincial HAT coordination units and entered into the database. Data were retrieved for 15 086 of 15 741 cases reported in the two provinces for the period (96%). Compliance with post-treatment follow-up was very poor in both provinces; only 25% had undergone at least one post-treatment follow-up examination, <1% had undergone the required four follow-up examinations. Relapse rates among those presenting for follow-up were high in Kasai (18%) but low in Bandundu (0.3%). High relapse rates in Kasai and poor compliance with post-treatment follow-up in both provinces are important problems that the HAT control program urgently needs to address. Moreover, in analogy to tuberculosis control programs, HAT control programs need to adopt a recording and reporting routine that includes reporting on treatment outcomes. © 2012 Blackwell Publishing Ltd.

  9. Evaluation of p,p'-DDT as a reference toxicant in bioassays

    USGS Publications Warehouse

    Marking, Leif L.

    1966-01-01

    p,p'-DDT was tested as a reference standard toxicant against 19 species of freshwater fish, including 39 lots from 10 sources. In particular, the rapidity, nonselectivity, and consistency of its toxicity to fish were evaluated in 96-hour static bioassays. The chemical was rapidly and consistently toxic to lake trout, carp, green sunfish, bluegill, and yellow perch. It lacked either rapid or consistent toxicity to rainbow trout, brook trout, goldfish, fathead minnows, and longear sunfish in 96-hour tests. Thus, p,p'-DDT is of limited usefulness as a reference standard toxicant in large bioassays with many species of fish.

  10. Results of external quality-assurance program for the National Atmospheric Deposition Program and National Trends Network during 1985

    USGS Publications Warehouse

    Brooks, M.H.; Schroder, L.J.; Willoughby, T.C.

    1988-01-01

    External quality assurance monitoring of the National Atmospheric Deposition Program (NADP) and National Trends Network (NTN) was performed by the U.S. Geological Survey during 1985. The monitoring consisted of three primary programs: (1) an intersite comparison program designed to assess the precision and accuracy of onsite pH and specific conductance measurements made by NADP and NTN site operators; (2) a blind audit sample program designed to assess the effect of routine field handling on the precision and bias of NADP and NTN wet deposition data; and (3) an interlaboratory comparison program designed to compare analytical data from the laboratory processing NADP and NTN samples with data produced by other laboratories routinely analyzing wet deposition samples and to provide estimates of individual laboratory precision. An average of 94% of the site operators participated in the four voluntary intersite comparisons during 1985. A larger percentage of participating site operators met the accuracy goal for specific conductance measurements (average, 87%) than for pH measurements (average, 67%). Overall precision was dependent on the actual specific conductance of the test solution and independent of the pH of the test solution. Data for the blind audit sample program indicated slight positive biases resulting from routine field handling for all analytes except specific conductance. These biases were not large enough to be significant for most data users. Data for the blind audit sample program also indicated that decreases in hydrogen ion concentration were accompanied by decreases in specific conductance. Precision estimates derived from the blind audit sample program indicate that the major source of uncertainty in wet deposition data is the routine field handling that each wet deposition sample receives. Results of the interlaboratory comparison program were similar to results of previous years ' evaluations, indicating that the participating laboratories produced comparable data when they analyzed identical wet deposition samples, and that the laboratory processing NADP and NTN samples achieved the best analyte precision of the participating laboratories. (Author 's abstract)

  11. In vitro bioassay for reactive toxicity towards proteins implemented for water quality monitoring.

    PubMed

    Tang, Janet Y M; Glenn, Eva; Thoen, Hanne; Escher, Beate I

    2012-03-01

    Reactive organic chemicals comprise a large number of compounds with a variety of reactive moieties. While most assays for reactive toxicity focus on DNA damage, reactivity towards proteins can also lead to irreparable damage, but reactivity towards proteins is typically not included in any test battery for water quality assessment. Glutathione (GSH) is a small tripeptide whose cysteine moiety can serve as a model for nucleophilic sites on proteins. GSH is also an important indicator of detoxification processes and the redox status of cells and due to its protective role, depletion of GSH ultimately leads to adverse effects. A bioassay based on genetically modified Escherichia coli strains was used to quantify the specific reactivity towards the protein-like biological nucelophile GSH. The significance of GSH for detoxification was assessed by comparing the growth inhibition induced by reference chemicals or water samples in a GSH-deficient strain to its fully functional parent strain. The GSH deficient strain showed the same sensitivity as the GSH proficient strain to non-reactive and DNA damaging chemicals, but was more sensitive to chemicals that attack cysteine in proteins. The difference in effect concentrations for 50% inhibition of growth assessed as biomass increase (EC(50)) between the two strains indicates the relevance of GSH conjugation as a detoxification step as well as direct reactivity with cysteine-containing proteins. Seven reference compounds serving as positive and negative controls were investigated. The E. coli strain that lacks GSH was four times more sensitive towards the positive control Sea-Nine, while negative controls benzo[a]pyrene, 2-aminoanthracene, phenol, t-butylhydroquinone, methyl methane sulfonate and 4-nitroquinoline oxide showed equal effect concentrations in both strains. Water samples collected across an indirect potable reuse scheme representing the complete water cycle from sewage to drinking water in South East Queensland, Australia were used to evaluate the applicability of the E. coli assay for reactive toxicity in water samples. While the EC(50) values of the GSH+ strain showed similar trends as in other biological endpoints over the various treatment chains, the specific response indicative of protein damage was only observed in samples that had undergone chlorination as a disinfection process. High natural organic matter or other matrix components disturbed the bioassay so much that we recommend it for future routine testing only in tertiary treated water or drinking water. This journal is © The Royal Society of Chemistry 2012

  12. Comparison of mouse and swine bioassays for determination of soil arsenic relative bioavailability

    EPA Science Inventory

    Evaluation of soil arsenic (As) relative bioavailability (RBA) is essential to accurately assess human exposure to As contaminated soils via the incidental ingestion pathway. A variety of animal bioassays have been developed to estimate As RBA in contaminated soils and dusts, wit...

  13. Book Review: Bioassays with Arthropods: 2nd Edition

    USDA-ARS?s Scientific Manuscript database

    The technical book "Bioassays with Arthropods: 2nd Edition" (2007. Jacqueline L. Robertson, Robert M. Russell, Haiganoush K, Preisler and N. E. Nevin, Eds. CRC Press, Boca Raton, FL, 224 pp.) was reviewed for the scientific readership of the peer-reviewed publication Journal of Economic Entomology. ...

  14. SUPERNUMERARY RIBS IN DEVELOPMENTAL TOXICITY BIOASSAYS AND IN HUMAN POPULATIONS: INCIDENCE AND BIOLOGICAL SIGNIFICANCE

    EPA Science Inventory

    Abstract
    Supernumerary or accessory ribs (SNR), either lumbar (LSNR) or cervical (CSNR) are a common finding in standard developmental toxicology bioassays. The biological significance of these anomalies within the regulatory arena has been problematic and the subject of some...

  15. Susceptibility of Bagrada hilaris (Hemiptera: Pentatomidae) to insecticides in laboratory and greenhouse bioassays

    USDA-ARS?s Scientific Manuscript database

    Field-collected populations of Bagrada hilaris (Burmeister) from Coachella Valley, CA, Imperial Valley, CA, Riverside, CA and Yuma Valley, AZ, were evaluated for susceptibility to several active ingredients representing ten classes of insecticide chemistry. Both leaf-spray and leaf-dip bioassays wer...

  16. Relationships of maternal and fetal weight changes in developmental toxicology bioassays

    EPA Science Inventory

    Standard developmental toxicology bioassays are designed to identify agents with the potential to induce adverse effects in the embryo/fetus. Guidelines require the inclusion of a dose level(s) that induces “overt maternal toxicity”. The common occurrence of dose levels at which ...

  17. A BIOASSAY THAT IDENTIFIES POSTNATAL FUNCTIONAL DEFICITS IN MICE PRENATALLY EXPOSED TO XENOBIOTICS

    EPA Science Inventory

    Experimental strategies to evaluate adverse postnatal effects due to prenatal exposure exist for many organ systems. Often, however, there is insufficient information to suggest that a particular organ system(s) may be sensitive to the test agent. A single bioassay to identify ...

  18. Utilizing high throughput bioassays to characterize the bioactivity of complex environmental samples

    EPA Science Inventory

    Bioassays can be employed to evaluate the integrated effects of complex mixtures of both known and unidentified contaminants present in environmental samples. However, such methods have typically focused on one or a few bioactivities despite the fact that the chemicals in a mixtu...

  19. Impact of application site on the efficacy of two topically-applied insecticides to Culex quinquefasciatus Say

    USDA-ARS?s Scientific Manuscript database

    Ultra-low volume and low volume insecticide treatments commonly used to control mosquito populations were evaluated for efficacy against Culex quinquefasciatus using a topical bioassay technique. Traditional topical bioassays focus pesticide application to the mesothoracic pleural area. Although, in...

  20. Artificial diets for life tables bioassays of TPB in Mississippi

    USDA-ARS?s Scientific Manuscript database

    Two artificial diets for mass rearing and bioassay of the tarnished plant bug, (TPB), Lygus lineolaris Palisot de Beauvois, (Hemiptera: Miridae) were modified and developed, respectively. The first diet is a modification of a semisolid artificial diet (NI diet), which permits large scale rearing of ...

  1. Micro-organism distribution sampling for bioassays

    NASA Technical Reports Server (NTRS)

    Nelson, B. A.

    1975-01-01

    Purpose of sampling distribution is to characterize sample-to-sample variation so statistical tests may be applied, to estimate error due to sampling (confidence limits) and to evaluate observed differences between samples. Distribution could be used for bioassays taken in hospitals, breweries, food-processing plants, and pharmaceutical plants.

  2. Sixth plot of the carcinogenic potency database: results of animal bioassays published in the General Literature 1989 to 1990 and by the National Toxicology Program 1990 to 1993.

    PubMed Central

    Gold, L S; Manley, N B; Slone, T H; Garfinkel, G B; Ames, B N; Rohrbach, L; Stern, B R; Chow, K

    1995-01-01

    This paper presents two types of information from the Carcinogenic Potency Database (CPDB): (a) the sixth chronological plot of analyses of long-term carcinogenesis bioassays, and (b) an index to chemicals in all six plots, including a summary compendium of positivity and potency for each chemical (Appendix 14). The five earlier plots of the CPDB have appeared in this journal, beginning in 1984 (1-5). Including the plot in this paper, the CPDB reports results of 5002 experiments on 1230 chemicals. This paper includes bioassay results published in the general literature between January 1989 and December 1990, and in Technical Reports of the National Toxicology Program between January 1990 and June 1993. Analyses are included on 17 chemicals tested in nonhuman primates by the Laboratory of Chemical Pharmacology, National Cancer Institute. This plot presents results of 531 long-term, chronic experiments of 182 test compounds and includes the same information about each experiment in the same plot format as the earlier papers: the species and strain of test animal, the route and duration of compound administration, dose level and other aspects of experimental protocol, histopathology and tumor incidence, TD50 (carcinogenic potency) and its statistical significance, dose response, author's opinion about carcinogenicity, and literature citation. We refer the reader to the 1984 publications (1,6,7) for a detailed guide to the plot of the database, a complete description of the numerical index of carcinogenic potency, and a discussion of the sources of data, the rationale for the inclusion of particular experiments and particular target sites, and the conventions adopted in summarizing the literature. The six plots of the CPDB are to be used together since results of individual experiments that were published earlier are not repeated. Appendix 14 is designed to facilitate access to results on all chemicals. References to the published papers that are the source of experimental data are reported in each of the published plots. For readers using the CPDB extensively, a combined plot is available of all results from the six separate plot papers, ordered alphabetically by chemical; the combined plot in printed form or on computer tape or diskette is available from the first author. A SAS database is also available. PMID:8741772

  3. Monitoring Cyp2b10 mRNA expression at cessation of 2-year carcinogenesis bioassay in mouse liver provides evidence for a carcinogenic mechanism devoid of human relevance: The dalcetrapib experience

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoflack, J-C.; Mueller, L., E-mail: Lutz.Mueller@roche.com; Fowler, S.

    2012-03-15

    Introduction: Dalcetrapib is a cholesteryl ester transfer protein (CETP) modulator in clinical assessment for cardiovascular outcome benefits. In compliance with regulatory requirements, dalcetrapib was evaluated in rodent 2-year carcinogenesis bioassays. In the mouse bioassay, male mice demonstrated increased liver weight and statistically increased incidences of hepatocellular adenoma/carcinoma. Hepatic cytochrome p450 (Cyp) 2b10 mRNA induction and increased Cyp2b10 enzyme activity signify activation of hepatic nuclear receptor constitutive androstane receptor (CAR), a widely established promoter of rodent-specific hepatic tumors. We therefore monitored hepatic Cyp2b10 mRNA and its enzyme activity in a subset of dalcetrapib-treated male mice from the bioassay. Methods: Liver samplesmore » were obtained from ∼ 1/3 of male mice from each dose group including vehicle-controls (mean and earliest study day of death 678 and 459 respectively). Quantitative real time PCR (qRT-PCR) was performed to determine Cyp2b10 mRNA expression and Cyp1a-, Cyp2b10- and Cyp3a-selective activities were monitored. Results: Cyp2b10 mRNA was strongly induced by dalcetrapib with an expected wide inter-individual variation (5–1421-fold). Group average fold-induction versus vehicle-controls showed a dose-related increase from 48-fold (250 mg/kg/day) to 160-fold (750 mg/kg/day), which declined slightly at 2000 mg/kg/day (97-fold). Cyp enzyme activities showed approximate doubling of total Cyp P450 content per milligram protein and a 9-fold increase in Cyp2b10-selective pentoxyresorufin O-dealkylase activity (750 mg/kg/day). Discussion: These data from hepatic Cyp2b10 monitoring are strongly suggestive of CAR activation by dalcetrapib, a mechanism devoid of relevance towards hepatocarcinogenesis in humans; results show feasibility of Cyp2b10 as a surrogate marker for this mechanism at cessation of a carcinogenesis bioassay. -- Highlights: ► Liver tumors were induced in male mice by dalcetrapib in a 2-y study (bioassay). ► Cyp2b10 induction typifies activation of nuclear receptor CAR in mouse liver. ► First report of hepatic Cyp2b10 monitoring at the end of a mouse bioassay. ► Cyp2b10 induction supports CAR activation by dalcetrapib in mouse bioassay. ► CAR activation is a mechanism of hepatic tumorigenesis of no relevance to humans.« less

  4. Transtheoretical model-based postpartum sexual health education program improves women's sexual behaviors and sexual health.

    PubMed

    Lee, Jian-Tao; Tsai, Jia-Ling

    2012-04-01

    Postpartum sexual health education was once routinely administered to postpartum women, but few interventions were specifically described or clearly based on theory, and few sexual interventions affected women's sexual behaviors. To evaluate the effectiveness of a refined theory-based interactive postpartum sexual health education program (IPSHEP) in enhancing postpartum women's sexual behavior and health. For this prospective, randomized controlled trial, 250 participants were randomized to three groups. Experimental group A received our refined theory-based IPSHEP. Experimental group B received only an interactive, self-help pamphlet. The control group received routine education (a 10- to 15-minute educational talk and a sexual health pamphlet without an interactive design). Data were collected at baseline, 3 days, 2 months, and 3 months postpartum. Postpartum women's sexual self-efficacy (SSE), diversity of sexual activity (DSA), return to sexual activity, and sexual satisfaction (SS). Women who received our theory-based postpartum sexual health education program had significantly greater SSE (P < 0.05) and greater DSA (P < 0.05), and tended to resume their sexual life earlier than women in the routine teaching and interactive pamphlet-only groups (P < 0.05). However, the SS levels of postpartum women who received our program did not differ significantly from those of women who received routine teaching or the interactive pamphlet only.   Our findings suggest that a theory-based postpartum sexual health education program improved women's sexual health and sexual behavior and that the transtheoretical model can be translated into practice, supporting its use to enhance the sexual health of postpartum women. Despite the lack of a significant effect on SS, women who received our theory-based postpartum sexual health education program tended to maintain their prepregnancy level of SS in early postpartum. © 2011 International Society for Sexual Medicine.

  5. [Assessing program sustainability in public health organizations: a tool-kit application in Haiti].

    PubMed

    Ridde, V; Pluye, P; Queuille, L

    2006-10-01

    Public health stakeholders are concerned about program sustainability. However, they usually conceive sustainability in accordance with financial criteria for at least one reason. No simple frameworks are operationally and theoretically sound enough to globally evaluate program sustainability. The present paper aims to describe an application of one framework assessment tool used to evaluate the sustainability level and process of a Nutritional Care Unit managed by a Swiss humanitarian agency to fight against severe child malnutrition in a Haitian area. The managing agency is committed to put this Unit back into the structure of a local public hospital. The evaluation was performed within the sustainability framework proposed in a former article. Data were collected with a combination of tools, semi-structured interviews (n=33, medical and support staff from the agency and the hospital), participatory observation and document review. Data concerned the four characteristics of organizational routines (memory, adaptation, values and rules) enabling assess to the level of sustainability. In addition, data were related to three types of events distinguishing routinization processes from implementation processes: specific events of routinization, routinization-implementation joint events, and specific events of implementation. Data analysis was thematic and results were validated by actors through a feed-back session and written comments. The current level of sustainability of the Nutritional Care Unit within the Hospital is weak: weak memory, high adaptation, weak sharing of values and rules. This may be explained by the sustainability process, and the absence of specific routinization events. The relevance of such processes is reasonable, while it has been strongly challenged in the troublesome Haitian context. Riots have been widespread over the last years, creating difficulties for the Hospital. This experience suggests the proposed framework and sustainability assessment tools are useful when the context permits scrutinization of program sustainability.

  6. Laboratory and Simulated Field Bioassays to Evaluate Larvicidal Activity of Pinus densiflora Hydrodistillate, Its Constituents and Structurally Related Compounds against Aedes albopictus, Aedes aegypti and Culex pipiens pallens in Relation to Their Inhibitory Effects on Acetylcholinesterase Activity

    PubMed Central

    Lee, Dong Chan; Ahn, Young-Joon

    2013-01-01

    The toxicity of Pinus densiflora (red pine) hydrodistillate, its 19 constituents and 28 structurally related compounds against early third-instar larvae of Aedes albopictus (Ae. albopictus), Aedes aegypti (Ae. aegypti) and Culex pipiens palles (Cx. p. pallens) was examined using direct-contact bioassays. The efficacy of active compounds was further evaluated in semi-field bioassays using field-collected larval Cx. p. pallens. Results were compared with those of two synthetic larvicides, temephos and fenthion. In laboratory bioassays, Pinus densiflora hydrodistillate was found to have 24 h LC50 values of 20.33, 21.01 and 22.36 mg/L against larval Ae. albopictus, Ae. aegypti and Cx. p. pallens respectively. Among the identified compounds, thymol, δ-3-carene and (+)-limonene exhibited the highest toxicity against all three mosquito species. These active compounds were found to be nearly equally effective in field trials as well. In vitro bioassays were conducted to examine the acetylcholinesterase (AChE) inhibitory activity of 10 selected compounds. Results showed that there is a noticeable correlation between larvicidal activity and AChE inhibitory activity. In light of global efforts to find alternatives for currently used insecticides against disease vector mosquitoes, Pinus densiflora hydrodistillate and its constituents merit further research as potential mosquito larvicides. PMID:26464387

  7. Enhancing the response of CALUX and CAFLUX cell bioassays for quantitative detection of dioxin-like compounds

    PubMed Central

    ZHAO, Bin; BASTON, David S.; KHAN, Elaine; SORRENTINO, Claudio; DENISON, Michael S.

    2011-01-01

    Reporter genes produce a protein product in transfected cells that can be easily measured in intact or lysed cells and they have been extensively used in numerous basic and applied research applications. Over the past 10 years, reporter gene assays have been widely accepted and used for analysis of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related dioxin-like compounds in various types of matrices, such as biological, environmental, food and feed samples, given that high-resolution instrumental analysis techniques are impractical for large-scale screening analysis. The most sensitive cell-based reporter gene bioassay systems developed are the mechanism-based CALUX (Chemically Activated Luciferase Expression) and CAFLUX (Chemically Activated Fluorescent Expression) bioassays, which utilize recombinant cell lines containing stably transfected dioxin (AhR)-responsive firefly luciferase or enhanced green fluorescent protein (EGFP) reporter genes, respectively. While the current CALUX and CAFLUX bioassays are very sensitive, increasing their lower limit of sensitivity, magnitude of response and dynamic range for chemical detection would significantly increase their utility, particularly for those samples that contain low levels of dioxin-like HAHs (i.e., serum). In this study, we report that the addition of modulators of cell signaling pathways or modification of cell culture conditions results in significant improvement in the magnitude and overall responsiveness of the existing CALUX and CAFLUX cell bioassays. PMID:21394221

  8. Assessment of acrylamide toxicity using a battery of standardised bioassays.

    PubMed

    Zovko, Mira; Vidaković-Cifrek, Željka; Cvetković, Želimira; Bošnir, Jasna; Šikić, Sandra

    2015-12-01

    Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms.

  9. Cancer risk assessment of polycyclic aromatic hydrocarbon contaminated soils determined using bioassay-derived levels of benzo[a]pyrene equivalents.

    PubMed

    Lemieux, Christine L; Long, Alexandra S; Lambert, Iain B; Lundstedt, Staffan; Tysklind, Mats; White, Paul A

    2015-02-03

    Here we evaluate the excess lifetime cancer risk (ELCR) posed by 10 PAH-contaminated soils using (i) the currently advocated, targeted chemical-specific approach that assumes dose additivity for carcinogenic PAHs and (ii) a bioassay-based approach that employs the in vitro mutagenic activity of the soil fractions to determine levels of benzo[a]pyrene equivalents and, by extension, ELCR. Mutagenic activity results are presented in our companion paper.1 The results show that ELCR values for the PAH-containing fractions, determined using the chemical-specific approach, are generally (i.e., 8 out of 10) greater than those calculated using the bioassay-based approach; most are less than 5-fold greater. Only two chemical-specific ELCR estimates are less than their corresponding bioassay-derived values; differences are less than 10%. The bioassay-based approach, which permits estimation of ELCR without a priori knowledge of mixture composition, proved to be a useful tool to evaluate the chemical-specific approach. The results suggest that ELCR estimates for complex PAH mixtures determined using a targeted, chemical-specific approach are reasonable, albeit conservative. Calculated risk estimates still depend on contentious PEFs and cancer slope factors. Follow-up in vivo mutagenicity assessments will be required to validate the results and their relevance for human health risk assessment of PAH-contaminated soils.

  10. Proof of concept for a novel insecticide bioassay based on sugar feeding by adult Aedes aegypti (Stegomyia aegypti).

    PubMed

    Stell, F M; Roe, R M; Arellano, C; Kennedy, L; Thornton, H; Saavedra-Rodriguez, K; Wesson, D M; Black, W C; Apperson, C S

    2013-09-01

    Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae) is the principal vector of dengue and yellow fever viruses in tropical and subtropical regions of the world. Disease management is largely based on mosquito control achieved by insecticides applied to interior resting surfaces and through space sprays. Population monitoring to detect insecticide resistance is a significant component of integrated disease management programmes. We developed a bioassay method for assessing insecticide susceptibility based on the feeding activity of mosquitoes on plant sugars. Our prototype sugar-insecticide feeding bioassay system was composed of inexpensive, disposable components, contained minimal volumes of insecticide, and was compact and highly transportable. Individual mosquitoes were assayed in a plastic cup that contained a sucrose-permethrin solution. Trypan blue dye was added to create a visual marker in the mosquito's abdomen for ingested sucrose-permethrin solution. Blue faecal spots provided further evidence of solution ingestion. With the sugar-insecticide feeding bioassay, the permethrin susceptibility of Ae. aegypti females from two field-collected strains was characterized by probit analysis of dosage-response data. The field strains were also tested by forced contact of females with permethrin residues on filter paper. Dosage-response patterns were similar, indicating that the sugar-insecticide feeding bioassay had appropriately characterized the permethrin susceptibility of the two strains. © 2012 The Royal Entomological Society.

  11. Effects of salinity, pH and temperature on the re-establishment of bioluminescence and copper or SDS toxicity in the marine dinoflagellate Pyrocystis lunula using bioluminescence as an endpoint

    USGS Publications Warehouse

    Craig, J.M.; Klerks, P.L.; Heimann, K.; Waits, J.L.

    2003-01-01

    Pyrocystis lunula is a unicellular, marine, photoautotrophic, bioluminescent dinoflagellate. This organism is used in the Lumitox ?? bioassay with inhibition of bioluminescence re-establishment as the endpoint. Experiments determined if acute changes in pH, salinity, or temperature had an effect on the organisms' ability to re-establish bioluminescence, or on the bioassay's potential to detect sodium dodecyl sulfate (SDS) and copper toxicity. The re-establishment of bioluminescence itself was not very sensitive to changes in pH within the pH 6-10 range, though reducing pH from 8 to levels below 6 decreased this capacity. Increasing the pH had little effect on Cu or SDS toxicity, but decreasing the pH below 7 virtually eliminated the toxicity of either compound in the bioassay. Lowering the salinity from 33 to 27??? or less resulted in a substantial decrease in re-establishment of bioluminescence, while increasing the salinity to 43 or 48 ??? resulted in a small decline. Salinity had little influence on the bioassay's quantification of Cu toxicity, while the data showed a weak negative relationship between SDS toxicity and salinity. Re-establishment of bioluminescence showed a direct dependence on temperature, but only at 10??C did temperature have an obvious effect on the toxicity of Cu in this bioassay. ?? 2003 Elsevier Science Ltd. All rights reserved.

  12. Risk assessment for selected xenobiotics by bioassay methods with higher plants

    NASA Astrophysics Data System (ADS)

    Günther, Petra; Pestemer, Wilfried

    1990-05-01

    Different bioassays with higher plants were approved for use in a bioassay procedure for testing of xenobiotics according to the German Chemicals Act. Selected environmental pollutants (atrazine, cadmium chloride, 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, thiourea), all from a list of reference chemicals, were tested with these methods. Dose-response curves for growth of oats and turnips were evaluated in soil and vermiculite (nonsorptive substrate), and availability to plants was calculated by comparing the EC50 values for one chemical in both substrates. The most active chemical was atrazine, followed by 2,6-dichlorobenzonitrile, pentachlorophenol, potassium dichromate, cadmium chloride, and thiourea. The least available compound to plants was pentachlorophenol, tested with turnips ( Brassica rapa var. rapa). The strongest inhibition of germination, demonstrated in an in vitro assay with garden cress ( Lepidium sativum), was found with 2,6-dichlorobenzonitrile, the lowest with atrazine. The effect of an extended exposure of the plants to the chemicals was evaluated in a long-term bioassay with oats ( Avena sativa) in hydroponic culture. Several dose-response curves during the growing period were derived. It was found that the EC50 values for atrazine and thiourea decreased markedly during the first four weeks; thereafter the changes were much smaller. As an overall conclusion, a bioassay procedure is proposed that can be included in the graduated plan recommended by the German Chemicals Act.

  13. Evaluation of planar halogenated and polycyclic aromatic hydrocarbons in estuarine sediments using ethoxyresorufin-O-deethylase induction of H4IIE cells

    USGS Publications Warehouse

    Gale, R.W.; Long, E.R.; Schwartz, T.R.; Tillitt, D.E.

    2000-01-01

    Polycyclic aromatic hydrocarbons (PAHs) and planar halogenated hydrocarbons (PHHs), including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) were determined in fractionated sediment extracts from the Hudson-Raritan estuary and Newark Bay, New Jersey, USA, as part of a comprehensive risk assessment. Contributions of PCDDs/PCDFs, PCBs, and PAHs to the total toxic equivalents (TEQs) were measured using an H4IIE bioassay and calculated from instrumentally determined concentrations using international toxic equivalency factors. The H4IIE TEQs of whole and fractionated extracts were compared to calculated TEQs to investigate the applicability of the bioassay approach for evaluating 7-ethoxyresorufin-O-deethylease induction by PHHs and PAHs present together in complex mixtures. Although 2,3,7,8-tetrachlorodibenzo-p-dioxin contributed from 41 to 79% of the calculated TEQs from PCDDs/PCDFs and planar PCBs in all sediments sampled, the PAH-containing fractions accounted for >80% of the total TEQs determined either instrumentally or by bioassay. Calculated TEQs from PAHs, based on reported toxic equivalency factors for only seven PAHs, were severalfold greater than the bioassay-derived TEQs of PAH-only fractions of the sediment extracts. Significant correlations were observed between bioassay and instrumentally determined toxic equivalents in the more purified fractions but not in fractions only purified by size-exclusion or argentate chromatographies alone.

  14. Cleavable DNA-protein hybrid molecular beacon: A novel efficient signal translator for sensitive fluorescence anisotropy bioassay.

    PubMed

    Hu, Pan; Yang, Bin

    2016-01-15

    Due to its unique features such as high sensitivity, homogeneous format, and independence on fluorescent intensity, fluorescence anisotropy (FA) assay has become a hotspot of study in oligonucleotide-based bioassays. However, until now most FA probes require carefully customized structure designs, and thus are neither generalizable for different sensing systems nor effective to obtain sufficient signal response. To address this issue, a cleavable DNA-protein hybrid molecular beacon was successfully engineered for signal amplified FA bioassay, via combining the unique stable structure of molecular beacon and the large molecular mass of streptavidin. Compared with single DNA strand probe or conventional molecular beacon, the DNA-protein hybrid molecular beacon exhibited a much higher FA value, which was potential to obtain high signal-background ratio in sensing process. As proof-of-principle, this novel DNA-protein hybrid molecular beacon was further applied for FA bioassay using DNAzyme-Pb(2+) as a model sensing system. This FA assay approach could selectively detect as low as 0.5nM Pb(2+) in buffer solution, and also be successful for real samples analysis with good recovery values. Compatible with most of oligonucleotide probes' designs and enzyme-based signal amplification strategies, the molecular beacon can serve as a novel signal translator to expand the application prospect of FA technology in various bioassays. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. The effects of a childbirth psychoeducation program on learned resourcefulness, maternal role competence and perinatal depression: a quasi-experiment.

    PubMed

    Ngai, Fei-Wan; Chan, Sally Wai-Chi; Ip, Wan-Yim

    2009-10-01

    Learned resourcefulness plays a significant role in facilitating maternal coping during the transition to motherhood. Given the growing evidence of perinatal depression and the frequent feeling of incompetence in the maternal role, the implementation of an effective intervention to promote maternal role competence and emotional well-being is essential. To determine the impact of a childbirth psychoeducation program based on the concept of learned resourcefulness on maternal role competence and depressive symptoms in Chinese childbearing women. A pretest-posttest, control group quasi-experimental design with repeated measures was used. The study was conducted in two regional public hospitals in Hong Kong that provide routine childbirth education programs with similar content and structure. One hospital was being randomly selected as the experimental hospital. A convenience sample of 184 Chinese pregnant women attending the childbirth education was recruited between October 2005 and April 2007. Inclusion criteria were primiparous with singleton and uneventful pregnancy, at gestation between 12 and 35 weeks, and did not have a past or familial psychiatric illness. The intervention was a childbirth psychoeducation program that was incorporated into the routine childbirth education in the experimental hospital. The experimental group (n=92) received the childbirth psychoeducation program and the routine childbirth education. The comparison group (n=92) received the routine childbirth education alone in the comparison hospital. Outcomes were measured by the Self-Control Schedule, Parenting Sense of Competence Scale-Efficacy subscale and Edinburgh Postnatal Depression Scale at baseline, immediately post-intervention, at 6 weeks and 6 months postpartum. Analysis was by intention to treat. Women receiving the childbirth psychoeducation program had significant improvement in learned resourcefulness at 6 weeks postpartum (p=0.004) and an overall reduction in depressive symptoms (p=0.01) from baseline to 6 months postpartum compared with those who only received the routine childbirth education after adjusting for baseline group differences on age and social support. No significant group difference was found on maternal role competence. The childbirth psychoeducation program appears to be a very promising intervention for promoting learned resourcefulness and minimizing the risk of perinatal depression in first-time Chinese childbearing women. Future empirical work is required to determine the effectiveness of extending the childbirth psychoeducation program into the early postpartum for the promotion of maternal role competence in Chinese childbearing women.

  16. Routine DNA testing

    USDA-ARS?s Scientific Manuscript database

    Routine DNA testing. It’s done once you’ve Marker-Assisted Breeding Pipelined promising Qantitative Trait Loci within your own breeding program and thereby established the performance-predictive power of each DNA test for your germplasm under your conditions. By then you are ready to screen your par...

  17. USE OF BIOASSAY-DIRECTED CHEMICAL ANALYSIS FOR IDENTIFYING MUTAGENIC COMPOUNDS IN URBAN AIR AND COMBUSTION EMISSIONS

    EPA Science Inventory

    Bioassay-directed chemical analysis fractionation has been used for 30 years to identify mutagenic classes of compounds in complex mixtures. Most studies have used the Salmonella (Ames) mutagenicity assay, and we have recently applied this methodology to two standard reference sa...

  18. Synthetic feeding stimulants enhance insecticide activity against western corn rootworm larvae, Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae)

    USDA-ARS?s Scientific Manuscript database

    In behavioral bioassays, the addition of a synthetic feeding stimulant blend improved the efficacy of the insecticide thiamethoxam against neonate western corn rootworm, Diabrotica virgifera virgifera LeConte, larvae. In 4-h bioassays, the concentration of thiamethoxam required for 50% mortality (LC...

  19. USE OF SALMONELLA MICROSUSPENSION BIOASSAY TO DETECT THE MUTGENICITY OF MUNITIONS COMPOUNDS AT LOW CONCENTRATIONS

    EPA Science Inventory



    Use of a Salmonella Microsuspension Bioassay to Detect the Mutagenicity of
    Munitions Compounds at Low Concentrations

    Abstract

    Past production and handling of munitions has resulted in soil contamination at various military facilities. Depending on...

  20. 40 CFR 227.6 - Constituents prohibited as other than trace contaminants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... included in the applicable marine water quality criteria, bioassay results on the liquid phase of the waste... possibility of danger associated -with their bioaccumulation in marine -organisms. (c) The potential for... of results of bioassays on liquid, suspended particulate, and solid phases of wastes according to...

  1. Bioassays for Evaluating Water Quality: Screening for total bioactivity to assess water safety

    EPA Science Inventory

    Bioassays are a potential solution for assessing complex samples since they screen for total bioactivity for a given pathway or mode of action (MOA), such as estrogen receptor activation, in the samples. Overall, they can account for the three challenges listed above, and can sim...

  2. Statistical considerations in the analysis of data from replicated bioassays

    USDA-ARS?s Scientific Manuscript database

    Multiple-dose bioassay is generally the preferred method for characterizing virulence of insect pathogens. Linear regression of probit mortality on log dose enables estimation of LD50/LC50 and slope, the latter having substantial effect on LD90/95s (doses of considerable interest in pest management)...

  3. Identification of Androgen Receptor Antagonists in Fish Using a Simple Bioassay with the Fathead Minnow Pimephales promelas .

    EPA Science Inventory

    Considerable effort has been expended on the development of bioassays to detect chemicals that affect endocrine function controlled by the vertebrate hypothalamic-pituitary-gonadal (HPG) axis via different mechanisms/modes of action (MOA). Antagonism of the androgen receptor (AR)...

  4. COMPARISON OF AN IN VIVO FISH VTG ASSAY WITH YES AND E-SCREEN

    EPA Science Inventory

    This study compares the efficacy of two in vitro, estrogen-sensitive bioassays to rank the "relative estrogenicity" of five natural, pharmaceutical and xenoestrogens with a newly developed in vivo bioassay. The E-SCREEN (MCF-7 tumor cells) and YES (Yeast Estrogen Screen) assays w...

  5. APPLICATION OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF A LEAD-CONTAMINATED SOIL

    EPA Science Inventory

    Earthworm acute toxicity, plant seed germination/root elongation (SG/RE) and plant genotoxicity bioassays were employed to evaluate the remediation of a lead-contaminated soil. The remediation involved removal of heavy metals by a soil washing/soil leaching treatment process. A p...

  6. AGE-RELATED DIFFERENCES IN SUSCEPTIBILITY TO CARCINOGENESIS - A QUANTITATIVE ANALYSIS OF EMPIRICAL ANIMAL BIOASSAY DATA

    EPA Science Inventory

    As part of its revision of cancer risk assessment guidelines, the U.S. Environmental Protection Agency has assembled and analyzed animal cancer bioassay data for exposures to mutagenic and putatively non-mutagenic chemicals over different periods of life. This paper reports an i...

  7. Antithrombin activity of medicinal plants of the Azores.

    PubMed

    de Medeiros, J M; Macedo, M; Contancia, J P; Nguyen, C; Cunningham, G; Miles, D H

    2000-09-01

    A chromogenic bioassay was utilized to determine the antithrombin activity of methylene chloride and methanol extracts prepared from 50 plants of Azores. Extracts of the six plants Hedychium gardneranum, Tropaeolum majus, Gunnera tinctoria, Hedera helix, Festuca jubata and Laurus azorica demonstrated activity of 78% or higher in this bioassay system.

  8. Maternal and fetal toxicity in developmental toxicology bioassays: Weight changes and their biological significance

    EPA Science Inventory

    Standard developmental toxicology bioassays are designed to identify agents with the potential to induce adverse effects in the embryo/fetus. Guidelines call for the inclusion of a dose level(s) that induces “overt maternal toxicity.” The possibility that general maternal toxicit...

  9. 21 CFR 172.860 - Fatty acids.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... (2) It is free of chick-edema factor: (i) As evidenced during the bioassay method for determining the chick-edema factor as prescribed in paragraph (c)(2) of this section; or (ii) As evidenced by the... the bioassay method prescribed in paragraph (c)(2) of this section for determining chick-edema factor...

  10. 21 CFR 172.860 - Fatty acids.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... (2) It is free of chick-edema factor: (i) As evidenced during the bioassay method for determining the chick-edema factor as prescribed in paragraph (c)(2) of this section; or (ii) As evidenced by the... the bioassay method prescribed in paragraph (c)(2) of this section for determining chick-edema factor...

  11. Facile silicification of plastic surface for bioassays

    PubMed Central

    Hong, Seonki; Park, Ki Soo; Weissleder, Ralph; Castro, Cesar M.; Lee, Hakho

    2017-01-01

    We herein report a biomimetic technique to modify plastic substrates for bioassays. The method first places a polydopamine adhesion layer to plastic surface, and then grows conformal silica coating. As proof of principle, we coated plastic microbeads to construct a disposable filter for point-of-care nucleic acid extraction. PMID:28134385

  12. SUTIL: system utilities routines programmer's reference manual

    NASA Technical Reports Server (NTRS)

    Harper, D.

    1976-01-01

    A package of FORTRAN callable subroutines which allows efficient communication of data between users and programs is described. Proper utilization of the SUTIL package to reduce program core requirements and expedite program development is emphasized.

  13. An assessment of potential health impacts on Utrok Atoll from exposure to cesium-137 (137Cs) and plutonium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hamilton, T

    2007-07-24

    Residual fallout contamination from the nuclear test program in the Marshall Islands is a concern to Marshall Islanders because of the potential health risks associated with exposure to residual fallout contamination in the environment. Scientists from Lawrence Livermore National Laboratory (LLNL) have been monitoring the amount of fallout radiation delivered to Utrok Atoll residents over the past 4 years. This briefing document gives an outline of our findings from the whole body counting and plutonium bioassay monitoring programs. Additional information can be found on the Marshall Islands web site (http://eed.lnl.gov/mi/). Cesium-137 is an important radioactive isotope produced in nuclear detonationsmore » and can be taken up from coral soils into locally grown food crop products that form an important part of the Marshallese diet. The Marshall Islands whole body counting program has clearly demonstrated that the majority of Utrok Atoll residents acquire a very small but measurable quantity of cesium-137 in their bodies (Hamilton et al., 2006; Hamilton et. al., 2007a; 2007b;). During 2006, a typical resident of Utrok Atoll received about 3 mrem of radiation from internally deposited cesium-137 (Hamilton et al., 2007a). The population-average dose contribution from cesium-137 is around 2% of the total radiation dose that people normally experience from naturally occurring radiation sources in the Marshall Islands and is thousands of times lower than the level where radiation exposure is known to produce measurable health effects. The existing dose estimates from the whole body counting and plutonium bioassay programs are also well below radiological protection standards for protection of the public as prescribed by U.S. regulators and international agencies including the Marshall Islands Nuclear Claim Tribunal (NCT). Similarly, the level of internally deposited plutonium found in Utrok Atoll residents is well within the range normally expected for people living in the Northern Hemisphere. In addition, the preliminary results of the bioassay program on Utrok Atoll (Hamilton et al., 2007b) provide clear evidence that residents of Utrok Atoll have never acquired a significant uptake of plutonium either through an acute exposure event or from long-term chronic exposure to plutonium in the environment. This information and data should provide a level of assurance to the Utrok Atoll population group and its leadership that the dose contribution from exposure to residual radioactive fallout contamination on Utrok Atoll is very low, and is not likely to have any discernible impact on human health. We also estimate that the dose contribution based on current radiological exposure conditions will not produce any additional cancer fatalities (or any other measurable health condition) above that normally expected to arise in a population group of similar size. The potential risks from any genetic illnesses caused by exposure to residual fallout contamination in the environment will be even lower still. In conclusion, the data and information developed from the radiological protection monitoring program on Utrok appear to support a consensus that it is safe to live on Utrok Atoll. The health risks from exposure to residual fallout contamination on the atoll are minimal when compared with other lifetime risks that people normally experience, and are very small when compared to the threshold where radiation health effects could be either medically diagnosed in an individual or epidemiologically discerned in a group of people.« less

  14. Cost-Effectiveness of Dengue Vaccination Programs in Brazil

    PubMed Central

    Shim, Eunha

    2017-01-01

    The first approved dengue vaccine, CYD-TDV, a chimeric, live-attenuated, tetravalent dengue virus vaccine, was recently licensed in 13 countries, including Brazil. In light of recent vaccine approval, we modeled the cost-effectiveness of potential vaccination policies mathematically based on data from recent vaccine efficacy trials that indicated that vaccine efficacy was lower in seronegative individuals than in seropositive individuals. In our analysis, we investigated several vaccination programs, including routine vaccination, with various vaccine coverage levels and those with and without large catch-up campaigns. As it is unclear whether the vaccine protects against infection or just against disease, our model incorporated both direct and indirect effects of vaccination. We found that in the presence of vaccine-induced indirect protection, the cost-effectiveness of dengue vaccination decreased with increasing vaccine coverage levels because the marginal returns of herd immunity decreases with vaccine coverage. All routine dengue vaccination programs that we considered were cost-effective, reducing dengue incidence significantly. Specifically, a routine dengue vaccination of 9-year-olds would be cost-effective when the cost of vaccination per individual is less than $262. Furthermore, the combination of routine vaccination and large catch-up campaigns resulted in a greater reduction of dengue burden (by up to 93%) than routine vaccination alone, making it a cost-effective intervention as long as the cost per course of vaccination is $255 or less. Our results show that dengue vaccination would be cost-effective in Brazil even with a relatively low vaccine efficacy in seronegative individuals. PMID:28500811

  15. 15 CFR 923.84 - Routine program changes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management...

  16. 15 CFR 923.84 - Routine program changes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE OCEAN AND COASTAL RESOURCE MANAGEMENT COASTAL ZONE MANAGEMENT PROGRAM REGULATIONS Amendments to and Termination of Approved Management...

  17. Computer programs for thermodynamic and transport properties of hydrogen (tabcode-II)

    NASA Technical Reports Server (NTRS)

    Roder, H. M.; Mccarty, R. D.; Hall, W. J.

    1972-01-01

    The thermodynamic and transport properties of para and equilibrium hydrogen have been programmed into a series of computer routines. Input variables are the pair's pressure-temperature and pressure-enthalpy. The programs cover the range from 1 to 5000 psia with temperatures from the triple point to 6000 R or enthalpies from minus 130 BTU/lb to 25,000 BTU/lb. Output variables are enthalpy or temperature, density, entropy, thermal conductivity, viscosity, at constant volume, the heat capacity ratio, and a heat transfer parameter. Property values on the liquid and vapor boundaries are conveniently obtained through two small routines. The programs achieve high speed by using linear interpolation in a grid of precomputed points which define the surface of the property returned.

  18. Avoiding Communication in the Lanczos Bidiagonalization Routine and Associated Least Squares QR Solver

    DTIC Science & Technology

    2015-04-12

    Avoiding communication in the Lanczos bidiagonalization routine and associated Least Squares QR solver Erin Carson Electrical Engineering and...Bidiagonalization Routine and Associated Least Squares QR Solver 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...throughout scienti c codes , are often the bottlenecks in application perfor- mance due to a low computation/communication ratio. In this paper we develop

  19. 25 CFR 170.116 - What activities are not eligible for IRR Program funding?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... INDIAN RESERVATION ROADS PROGRAM Indian Reservation Roads Program Policy and Eligibility Eligible Uses If... funds cannot be used for any of the following: (a) Routine maintenance work such as: grading shoulders...

  20. An Input Routine Using Arithmetic Statements for the IBM 704 Digital Computer

    NASA Technical Reports Server (NTRS)

    Turner, Don N.; Huff, Vearl N.

    1961-01-01

    An input routine has been designed for use with FORTRAN or SAP coded programs which are to be executed on an IBM 704 digital computer. All input to be processed by the routine is punched on IBM cards as declarative statements of the arithmetic type resembling the FORTRAN language. The routine is 850 words in length. It is capable of loading fixed- or floating-point numbers, octal numbers, and alphabetic words, and of performing simple arithmetic as indicated on input cards. Provisions have been made for rapid loading of arrays of numbers in consecutive memory locations.

  1. Computer Programs (Turbomachinery)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA computer programs are extensively used in design of industrial equipment. Available from the Computer Software Management and Information Center (COSMIC) at the University of Georgia, these programs are employed as analysis tools in design, test and development processes, providing savings in time and money. For example, two NASA computer programs are used daily in the design of turbomachinery by Delaval Turbine Division, Trenton, New Jersey. The company uses the NASA splint interpolation routine for analysis of turbine blade vibration and the performance of compressors and condensers. A second program, the NASA print plot routine, analyzes turbine rotor response and produces graphs for project reports. The photos show examples of Delaval test operations in which the computer programs play a part. In the large photo below, a 24-inch turbine blade is undergoing test; in the smaller photo, a steam turbine rotor is being prepared for stress measurements under actual operating conditions; the "spaghetti" is wiring for test instrumentation

  2. Biomimetic engineering of a generic cell-on-membrane architecture by microfluidic engraving for on-chip bioassays.

    PubMed

    Lee, Sang-Wook; Noh, Ji-Yoon; Park, Seung Chul; Chung, Jin-Ho; Lee, Byoungho; Lee, Sin-Doo

    2012-05-22

    We develop a biomimetic cell-on-membrane architecture in close-volume format which allows the interfacial biocompatibility and the reagent delivery capability for on-chip bioassays. The key concept lies in the microfluidic engraving of lipid membranes together with biological cells on a supported substrate with topographic patterns. The simultaneous engraving process of a different class of fluids is promoted by the front propagation of an air-water interface inside a flow-cell. This highly parallel, microfluidic cell-on-membrane approach opens a door to the natural biocompatibility in mimicking cellular stimuli-response behavior essential for diverse on-chip bioassays that can be precisely controlled in the spatial and temporal manner.

  3. Consensus guidelines for the use and interpretation of angiogenesis assays.

    PubMed

    Nowak-Sliwinska, Patrycja; Alitalo, Kari; Allen, Elizabeth; Anisimov, Andrey; Aplin, Alfred C; Auerbach, Robert; Augustin, Hellmut G; Bates, David O; van Beijnum, Judy R; Bender, R Hugh F; Bergers, Gabriele; Bikfalvi, Andreas; Bischoff, Joyce; Böck, Barbara C; Brooks, Peter C; Bussolino, Federico; Cakir, Bertan; Carmeliet, Peter; Castranova, Daniel; Cimpean, Anca M; Cleaver, Ondine; Coukos, George; Davis, George E; De Palma, Michele; Dimberg, Anna; Dings, Ruud P M; Djonov, Valentin; Dudley, Andrew C; Dufton, Neil P; Fendt, Sarah-Maria; Ferrara, Napoleone; Fruttiger, Marcus; Fukumura, Dai; Ghesquière, Bart; Gong, Yan; Griffin, Robert J; Harris, Adrian L; Hughes, Christopher C W; Hultgren, Nan W; Iruela-Arispe, M Luisa; Irving, Melita; Jain, Rakesh K; Kalluri, Raghu; Kalucka, Joanna; Kerbel, Robert S; Kitajewski, Jan; Klaassen, Ingeborg; Kleinmann, Hynda K; Koolwijk, Pieter; Kuczynski, Elisabeth; Kwak, Brenda R; Marien, Koen; Melero-Martin, Juan M; Munn, Lance L; Nicosia, Roberto F; Noel, Agnes; Nurro, Jussi; Olsson, Anna-Karin; Petrova, Tatiana V; Pietras, Kristian; Pili, Roberto; Pollard, Jeffrey W; Post, Mark J; Quax, Paul H A; Rabinovich, Gabriel A; Raica, Marius; Randi, Anna M; Ribatti, Domenico; Ruegg, Curzio; Schlingemann, Reinier O; Schulte-Merker, Stefan; Smith, Lois E H; Song, Jonathan W; Stacker, Steven A; Stalin, Jimmy; Stratman, Amber N; Van de Velde, Maureen; van Hinsbergh, Victor W M; Vermeulen, Peter B; Waltenberger, Johannes; Weinstein, Brant M; Xin, Hong; Yetkin-Arik, Bahar; Yla-Herttuala, Seppo; Yoder, Mervin C; Griffioen, Arjan W

    2018-05-15

    The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

  4. The CMC/3DPNS computer program for prediction of three-dimensional, subsonic, turbulent aerodynamic juncture region flow. Volume 3: Programmers' manual

    NASA Technical Reports Server (NTRS)

    Orzechowski, J. A.

    1982-01-01

    The CMC fluid mechanics program system was developed to transmit the theoretical evolution of finite element numerical solution methodology, applied to nonlinear field problems into a versatile computer code for comprehensive flow field analysis. A detailed view of the code from the standpoint of a computer programmer's use is presented. A system macroflow chart and detailed flow charts of several routines necessary to interact with a theoretican/user to modify the operation of this program are presented. All subroutines and details of usage, primarily for input and output routines are described. Integer and real scalars and a cross reference list denoting subroutine usage for these scalars are outlined. Entry points in dynamic storage vector IZ; the lengths of each vector accompanying the scalar definitions are described. A listing of the routines peculiar to the standard test case and a listing of the input deck and printout for this case are included.

  5. The current status of resistance to alpha-cypermethrin, ivermectin, and amitraz of the cattle tick (Rhipicephalus microplus) in Ecuador.

    PubMed

    Rodríguez-Hidalgo, Richar; Pérez-Otáñez, Ximena; Garcés-Carrera, Sandra; Vanwambeke, Sophie O; Madder, Maxime; Benítez-Ortiz, Washington

    2017-01-01

    Rhipicephalus microplus is widely distributed in tropical and subtropical areas of the world where livestock is a principal activity with great veterinary and economic importance. In Ecuador, this hematophagous ectoparasite has been observed between 0 and 2600 masl. One of the main tick control measures is the use of acaricides, which have been indiscriminately used worldwide and in Ecuador. In this country, no studies on acaricide resistance in Rhipicephalus microplus have been published. The current study aims to characterise the level of resistance of R. microplus against three main acaricides commonly used in Ecuador i.e. amitraz, alpha-cypermethrin and ivermectin to determine the level and pattern of dose-responses for R. microplus in 12 field populations (farms). The level of acaricide resistance was evaluated using three different bioassays: adult immersion test (AIT), larval package test (LPT) and larval immersion test (LIT), as recommended by the FAO. The predictive dose-responses were analysed by binomial logistics regression of the larval survival rate (resistance). In general, we found resistance of 67% for amitraz; 50% for alpha-cypermethrin and from 25 to 42% for ivermectin in the twelve field populations analysed. Resistance levels were studied in larval and adult bioassays, respectively, which were slightly modified for this study. For larval bioassays based on corrected mortality i.e. high (above 51%), medium (21-50%) and low (11-20%) resistance, percentages less than 10% were considered as susceptible. For the adult test, two resistance levels were used i.e. high (more than 76%) and medium (51 to 75%) resistance. Percentages lower than 50% were considered as susceptible. In this context, for larval bioassays, amitraz showed 21%, 38% and 8% for high, medium and low resistance, respectively. Alpha-cypermethrin presented 8%, 4 and 38% for high, medium and low resistance, respectively. Ivermectin presented 8%, 25% and 8% for high, medium and low resistance, respectively. For adult tests with amitraz 50% and 17% of the field populations showed average and high resistance, with evidences of average resistance to alpha-cypermethrin in 50% of the samples and average resistance against ivermectin in 25% of the farms. No statistical difference amongst the three bioassays was found and acaricide resistance was confirmed by logistic regression analysis; hence resistance (dose-responses) in each field populations differed, depending on the choice of the acaricide, frequent usage, frequency of treatment and farm management. The effective estimated dose needed to eliminate 99% of ticks is higher than dose recommended by the manufacturer. In conclusion, amitraz showed the highest resistance followed by ivermectin and alpha-cypermethrin and reveals differences on resistance in each individual field population. This information is important in order to establish the monitoring of resistance on each farm individually, contributing to the rational use of acaricides included in an integrated control program for R. microplus.

  6. The current status of resistance to alpha-cypermethrin, ivermectin, and amitraz of the cattle tick (Rhipicephalus microplus) in Ecuador

    PubMed Central

    Garcés-Carrera, Sandra; Vanwambeke, Sophie O.; Madder, Maxime; Benítez-Ortiz, Washington

    2017-01-01

    Rhipicephalus microplus is widely distributed in tropical and subtropical areas of the world where livestock is a principal activity with great veterinary and economic importance. In Ecuador, this hematophagous ectoparasite has been observed between 0 and 2600 masl. One of the main tick control measures is the use of acaricides, which have been indiscriminately used worldwide and in Ecuador. In this country, no studies on acaricide resistance in Rhipicephalus microplus have been published. The current study aims to characterise the level of resistance of R. microplus against three main acaricides commonly used in Ecuador i.e. amitraz, alpha-cypermethrin and ivermectin to determine the level and pattern of dose-responses for R. microplus in 12 field populations (farms). The level of acaricide resistance was evaluated using three different bioassays: adult immersion test (AIT), larval package test (LPT) and larval immersion test (LIT), as recommended by the FAO. The predictive dose-responses were analysed by binomial logistics regression of the larval survival rate (resistance). In general, we found resistance of 67% for amitraz; 50% for alpha-cypermethrin and from 25 to 42% for ivermectin in the twelve field populations analysed. Resistance levels were studied in larval and adult bioassays, respectively, which were slightly modified for this study. For larval bioassays based on corrected mortality i.e. high (above 51%), medium (21–50%) and low (11–20%) resistance, percentages less than 10% were considered as susceptible. For the adult test, two resistance levels were used i.e. high (more than 76%) and medium (51 to 75%) resistance. Percentages lower than 50% were considered as susceptible. In this context, for larval bioassays, amitraz showed 21%, 38% and 8% for high, medium and low resistance, respectively. Alpha-cypermethrin presented 8%, 4 and 38% for high, medium and low resistance, respectively. Ivermectin presented 8%, 25% and 8% for high, medium and low resistance, respectively. For adult tests with amitraz 50% and 17% of the field populations showed average and high resistance, with evidences of average resistance to alpha-cypermethrin in 50% of the samples and average resistance against ivermectin in 25% of the farms. No statistical difference amongst the three bioassays was found and acaricide resistance was confirmed by logistic regression analysis; hence resistance (dose-responses) in each field populations differed, depending on the choice of the acaricide, frequent usage, frequency of treatment and farm management. The effective estimated dose needed to eliminate 99% of ticks is higher than dose recommended by the manufacturer. In conclusion, amitraz showed the highest resistance followed by ivermectin and alpha-cypermethrin and reveals differences on resistance in each individual field population. This information is important in order to establish the monitoring of resistance on each farm individually, contributing to the rational use of acaricides included in an integrated control program for R. microplus. PMID:28388639

  7. Water Use Practices Limit the Effectiveness of a Temephos-Based Aedes aegypti Larval Control Program in Northern Argentina

    PubMed Central

    Garelli, Fernando M.; Espinosa, Manuel O.; Weinberg, Diego; Trinelli, María A.; Gürtler, Ricardo E.

    2011-01-01

    Background A five-year citywide control program based on regular application of temephos significantly reduced Aedes aegypti larval indices but failed to maintain them below target levels in Clorinda, northern Argentina. Incomplete surveillance coverage and reduced residuality of temephos were held as the main putative causes limiting effectiveness of control actions. Methodology The duration of temephos residual effects in household-owned water-holding tanks (the most productive container type and main target for control) was estimated prospectively in two trials. Temephos was applied using spoons or inside perforated small zip-lock bags. Water samples from the study tanks (including positive and negative controls) were collected weekly and subjected to larval mortality bioassays. Water turnover was estimated quantitatively by adding sodium chloride to the study tanks and measuring its dilution 48 hs later. Principal Findings The median duration of residual effects of temephos applied using spoons (2.4 weeks) was significantly lower than with zip-lock bags (3.4 weeks), and widely heterogeneous between tanks. Generalized estimating equations models showed that bioassay larval mortality was strongly affected by water type and type of temephos application depending on water type. Water type and water turnover were highly significantly associated. Tanks filled with piped water had high turnover rates and short-lasting residual effects, whereas tanks filled with rain water showed the opposite pattern. On average, larval infestations reappeared nine weeks post-treatment and seven weeks after estimated loss of residuality. Conclusions Temephos residuality in the field was much shorter and more variable than expected. The main factor limiting temephos residuality was fast water turnover, caused by householders' practice of refilling tanks overnight to counteract the intermittence of the local water supply. Limited field residuality of temephos accounts in part for the inability of the larval control program to further reduce infestation levels with a treatment cycle period of 3 or 4 months. PMID:21445334

  8. Outcomes Assessment in Dental Hygiene Programs.

    ERIC Educational Resources Information Center

    Grimes, Ellen B.

    1999-01-01

    A survey of 22 dental-hygiene-program directors found that programs routinely and effectively assess student outcomes and use the information for program improvements and to demonstrate accountability. Both policy and faculty/administrative support were deemed important to implementation. Time constraints were a major barrier. Outcomes-assessment…

  9. Space shuttle atmospheric revitalization subsystem/active thermal control subsystem computer program (users manual)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A shuttle (ARS) atmosphere revitalization subsystem active thermal control subsystem (ATCS) performance routine was developed. This computer program is adapted from the Shuttle EC/LSS Design Computer Program. The program was upgraded in three noteworthy areas: (1) The functional ARS/ATCS schematic has been revised to accurately synthesize the shuttle baseline system definition. (2) The program logic has been improved to provide a more accurate prediction of the integrated ARS/ATCS system performance. Additionally, the logic has been expanded to model all components and thermal loads in the ARS/ATCS system. (3) The program is designed to be used on the NASA JSC crew system division's programmable calculator system. As written the new computer routine has an average running time of five minutes. The use of desk top type calculation equipment, and the rapid response of the program provides the NASA with an analytical tool for trade studies to refine the system definition, and for test support of the RSECS or integrated Shuttle ARS/ATCS test programs.

  10. Simple, Inexpensive, and Rapid Way to Produce Bacillus subtilis Spores for the Guthrie Bioassay

    PubMed Central

    Franklin, Martha L.; Clark, William A.

    1981-01-01

    Esculin agar has been found to be a simple, inexpensive, rapid, and reliable means to promote production of spores of inhibitor-sensitive clones of Bacillus subtilis strains ATCC 6051 and 6633 for use in the Guthrie bioassay screening tests for genetic metabolic disorders. Images PMID:6790564

  11. A new in vitro bioassay system for discovery and quantitative evaluation of mosquito repellents

    USDA-ARS?s Scientific Manuscript database

    Mosquitoes are vectors of many pathogens that cause human diseases. Although prevention and control of immature stages is the best method to control mosquitoes, repellents play a significant role in reducing the risk of these diseases by preventing mosquito bites. The In vitro K & D bioassay system ...

  12. Bioassay-directed isolation and evaluation of Harmine from the terrestrial plant Peganum harmala L. for antibacterial activity against Flavobacterium columnare

    USDA-ARS?s Scientific Manuscript database

    The antibacterial activities of crude extracts obtained from the aerial portions and roots of Peganum harmala L. were evaluated against the common fish pathogenic bacteria species Edwardsiella ictaluri, Flavobacterium columnare, and Streptococcus iniae using a rapid bioassay. Enteric septicemia of c...

  13. Statistical correlations between GLC assay and smaller European elm bark beetle bioassay

    Treesearch

    Jack H. Barger; Roy A. Cuthbert; Donald G. Seegrist

    1973-01-01

    American elm trees, Ulmus americana L., were sprayed with methoxychlor by helicopter or mist blower, and twig crotches were collected from sprayed trees for bioassay of Scolytus multistriatus (Marsham) and GLC assay. Correlations established between the 2 assays were dependent on method of application and amount of methoxychlor...

  14. A comparative analysis of resistance testing methods in Aedes albopictus (Diptera: Culicidae) from St. Johns County, Florida

    USDA-ARS?s Scientific Manuscript database

    Aedes albopictus Skuse (Diptera: Culicidae) was tested for resistance to permethrin, bifenthrin, and malathion using Centers for Disease Control and Prevention (CDC) bottle bioassays and topical toxicology assays on adults and larval bioassays. Eggs were collected from 3 locations across St. Johns C...

  15. Microplate Bioassay for Determining Substrate Selectivity of "Candida rugosa" Lipase

    ERIC Educational Resources Information Center

    Wang, Shi-zhen; Fang, Bai-shan

    2012-01-01

    Substrate selectivity of "Candida rugosa" lipase was tested using "p"-nitrophenyl esters of increasing chain length (C[subscript 1], C[subscript 7], C[subscript 15]) using the high-throughput screening method. A fast and easy 96-well microplate bioassay was developed to help students learn and practice biotechnological specificity screen. The…

  16. Using a Macroalgal δ15N Bioassay to Detect Cruise Ship Waste Water Effluent Inputs

    EPA Science Inventory

    Nitrogen stable isotopes are a powerful tool for tracking sources of N to marine ecosystems. I used green macroalgae as a bioassay organism to evaluate if the δ15N signature of cruise ship waste water effluent (CSWWE) could be detected in Skagway Harbor, AK. Opportunistic green...

  17. SEDIMENT TOXICITY AND STORMWATER RUNOFF IN A CONTAMINATED RECEIVING SYSTEM: CONSIDERATION OF DIFFERENT BIOASSAYS IN THE LABORATORY AND FIELD. (R823873)

    EPA Science Inventory

    Several field and laboratory assays were employed below an urban storm sewer outfall to define the relationship between stormwater runoff and contaminant effects. Specifically, two bioassays that measure feeding rate as a toxicological endpoint were employed in the field and in t...

  18. Cumulative toxicity of an environmentally relevant mixture of nine regulated disinfection by-products in a multigenerational rat reproductive bioassay

    EPA Science Inventory

    CUMULATIVE TOXICITY OF AN ENVIRONMENTALLY RELEVANT MIXTURE OF NINE REGULATED DISINFECTION BY-PRODUCTS IN A MULTIGENERATIONAL RAT REPRODUCTIVE BIOASSAY J E Simmons, GR. Klinefelter, JM Goldman, AB DeAngelo, DS Best, A McDonald, LF Strader, AS Murr, JD Suarez, MH George, ES Hunte...

  19. Application of Site-Specific Calibration Data Using the CALUX by XDS Bioassay for Dioxin-Like Chemicals in Soil and Sediment Samples

    EPA Science Inventory

    The Chemically-Activated LUciferase gene eXpression (CALUX®) by Xenobiotic Detection Systems (XDS) bioassay was evaluated for determining the presence of dioxin and dioxin-like compounds in soil and sediment in two studies conducted under the U.S. Environmental Protection Agency...

  20. COMPARATIVE ESTROGENICITY OF ESTRADIOL, ETHYNYL ESTRADIOL AND DIETHYLSTILBESTROL IN AN IN VIVO, MALE SHEEPSHEAD MINNOW (CYPRINODON VARIEGATUS), VITELLOGENIN BIOASSAY

    EPA Science Inventory

    An in vivo bioassay for vitellogenin (VTG) synthesis was developed to screen individual chemicals or mixtures of chemicals for potentially estrogenic effects in a marine teleost model. An enzyme-linked immunosorbent assay (ELISA) was used to quantitate VTG synthesis in male sheep...

  1. USE OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    EPA Science Inventory

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ...

  2. Evaluation of the Methoxytriazine Herbicide Prometon Using a Short-term Fathead Minnow Reproduction Test and a Suite of in vitro Bioassays

    EPA Science Inventory

    This study used an array of in vitro bioassays to assess whether prometon, atraton, terbumeton, or secbumeton might act as potent (ant)agonists of the aryl hydrocarbon, estrogen, androgen, or glucocorticoid receptors and whether they might act as aromatase inhibitors or inducers ...

  3. OBSERVATIONS ON THE 10-DAY CHIRONOMUS TENTANS SURVIVAL AND GROWTH BIOASSAY IN EVALUATING GREAT LAKES SEDIMENTS

    EPA Science Inventory

    A 10-day bioassay with larval chironomids (Chironomus tentans) was used to evaluate sediment samples from harbors at Michigan City, IN, St. Joseph, MI, Grand Haven, MI and Toledo, OH for toxicity, based on the endpoints of survival, dry weight, and growth. Larval responses in se...

  4. Bioassay of plant growth from soils varying in active C and N fractions

    USDA-ARS?s Scientific Manuscript database

    Biologically active soil C and N fractions are important attributes of healthy soil. As a bioassay, we hypothesized that active soil C and N fractions would relate with plant dry matter production from unamended soil. Four replicate soil samples from 22 tall fescue fields in North Carolina and Virgi...

  5. Peroral bioassay of nucleopolyhedrosis viruses in larvae of western spruce budworm.

    Treesearch

    Mauro E. Martignoni; Paul J. Iwai

    1981-01-01

    The relative virulence of entomopathogenic viruses and the potency of virus preparations for control of destructive insects can be estimated reliably only by means of biological assay in the target species. A simple, yet sensitive peroral bioassay procedure is described for preparations of nucleopolyhedrosis viruses pathogenic for the western spruce budworm, ...

  6. Determining UV Inactivation of Toxoplasma gondii Oocysts by Using Cell Culture and a Mouse Bioassay

    EPA Science Inventory

    The effect of UV exposure on Toxoplasma gondii oocysts has not been completely defined for use in water disinfection. This study evaluated UV irradiated oocysts by three assays: a SCID mouse bioassay, an in vitro T. gondii oocyst plaque assay (TOP-assay), and a quantitative reve...

  7. The 10th Annual Bioassays and Bioanalytical Method Development Conference.

    PubMed

    Ma, Mark; Tudan, Christopher; Koltchev, Dolly

    2015-01-01

    The 10th Annual Bioassays and Bioanalytical Method Development Conference was hosted in Boston, MA, USA on 20-22 October 2014. This meeting brought together scientists from the biopharmaceutical and life sciences industries, the regulatory agency and academia to share and discuss current trends in cell-based assays and bioanalysis, challenges and ideas for the future of the bioassays and bioanalytical method development. The experiences associated with new and innovative technologies were evaluated as well as their impact on the current bioassays methodologies and bioanalysis workflow, including quality, feasibility, outsourcing strategies and challenges, productivity and compliance. Several presentations were also provided by members of the US FDA, sharing both scientific and regulatory paradigms including a most recent update on the position of the FDA with specific aspects of the draft Bioanalytical Method Validation guidance following its review of the industry's responses. The meeting was jointly coincided with the 15th Annual Immunogenicity for Biotherapeutics meeting, allowing for attendees to also familiarize themselves with new and emerging approaches to overcome the effect of immunogenicity, in addition to investigative strategies.

  8. Effect of three extraction techniques on submitochondrial particle and Microtox bioassays for airborne particulate matter.

    PubMed

    Torres-Pérez, Mónica I; Jiménez-Velez, Braulio D; Mansilla-Rivera, Imar; Rodríguez-Sierra, Carlos J

    2005-03-01

    The effect that three extraction techniques (e.g., Soxhlet, ultrasound and microwave-assisted extraction) have on the toxicity, as measured by submitochondrial particle (SMP) and Microtox assays, of organic extracts was compared from three sources of airborne particulate matter (APM). The extraction technique influenced the toxicity response of APM extracts and it was dependent on the bioassay method, and APM sample source. APM extracts from microwave-assisted extraction (MAE) were similar or more toxic than the conventional extraction techniques of Soxhlet and ultrasound, thus, providing an alternate extraction method. The microwave extraction technique has the advantage of using less solvent volume, less extraction time, and the capacity to simultaneously extract twelve samples. The ordering of APM toxicity was generally urban dust > diesel dust > PM10 (particles with diameter < 10 microm), thus, reflecting different chemical composition of the samples. This study is the first to report the suitability of two standard in-vitro bioassays for the future toxicological characterization of APM collected from Puerto Rico, with the SMP generally showing better sensitivity to the well-known Microtox bioassay.

  9. Metallic elements in fossil fuel combustion products: amounts and form of emissions and evaluation of carcinogenicity and mutagenicity.

    PubMed

    Vouk, V B; Piver, W T

    1983-01-01

    Metallic elements contained in coal, oil and gasoline are mobilized by combustion processes and may be emitted into the atmosphere, mainly as components of submicron particles. The information about the amounts, composition and form of metal compounds is reviewed for some fuels and combustion processes. Since metal compounds are always contained in urban air pollutants, they have to be considered whenever an evaluation of biological impact of air pollutants is made. The value of currently used bioassays for the evaluation of the role of trace metal compounds, either as major biologically active components or as modifiers of biological effects of organic compounds is assessed. The whole animal bioassays for carcinogenicity do not seem to be an appropriate approach. They are costly, time-consuming and not easily amenable to the testing of complex mixtures. Some problems related to the application and interpretation of short-term bioassays are considered, and the usefulness of such bioassays for the evaluation of trace metal components contained in complex air pollution mixtures is examined.

  10. Fluorescence-based bioassays for the detection and evaluation of food materials.

    PubMed

    Nishi, Kentaro; Isobe, Shin-Ichiro; Zhu, Yun; Kiyama, Ryoiti

    2015-10-13

    We summarize here the recent progress in fluorescence-based bioassays for the detection and evaluation of food materials by focusing on fluorescent dyes used in bioassays and applications of these assays for food safety, quality and efficacy. Fluorescent dyes have been used in various bioassays, such as biosensing, cell assay, energy transfer-based assay, probing, protein/immunological assay and microarray/biochip assay. Among the arrays used in microarray/biochip assay, fluorescence-based microarrays/biochips, such as antibody/protein microarrays, bead/suspension arrays, capillary/sensor arrays, DNA microarrays/polymerase chain reaction (PCR)-based arrays, glycan/lectin arrays, immunoassay/enzyme-linked immunosorbent assay (ELISA)-based arrays, microfluidic chips and tissue arrays, have been developed and used for the assessment of allergy/poisoning/toxicity, contamination and efficacy/mechanism, and quality control/safety. DNA microarray assays have been used widely for food safety and quality as well as searches for active components. DNA microarray-based gene expression profiling may be useful for such purposes due to its advantages in the evaluation of pathway-based intracellular signaling in response to food materials.

  11. Fluorescence-Based Bioassays for the Detection and Evaluation of Food Materials

    PubMed Central

    Nishi, Kentaro; Isobe, Shin-Ichiro; Zhu, Yun; Kiyama, Ryoiti

    2015-01-01

    We summarize here the recent progress in fluorescence-based bioassays for the detection and evaluation of food materials by focusing on fluorescent dyes used in bioassays and applications of these assays for food safety, quality and efficacy. Fluorescent dyes have been used in various bioassays, such as biosensing, cell assay, energy transfer-based assay, probing, protein/immunological assay and microarray/biochip assay. Among the arrays used in microarray/biochip assay, fluorescence-based microarrays/biochips, such as antibody/protein microarrays, bead/suspension arrays, capillary/sensor arrays, DNA microarrays/polymerase chain reaction (PCR)-based arrays, glycan/lectin arrays, immunoassay/enzyme-linked immunosorbent assay (ELISA)-based arrays, microfluidic chips and tissue arrays, have been developed and used for the assessment of allergy/poisoning/toxicity, contamination and efficacy/mechanism, and quality control/safety. DNA microarray assays have been used widely for food safety and quality as well as searches for active components. DNA microarray-based gene expression profiling may be useful for such purposes due to its advantages in the evaluation of pathway-based intracellular signaling in response to food materials. PMID:26473869

  12. Stability of amoxicillin-clavulanate in BACTEC medium determined by high-performance liquid chromatography and bioassay.

    PubMed Central

    Moore, T D; Horton, R; Utrup, L J; Miller, L A; Poupard, J A

    1996-01-01

    The stabilities of amoxicillin (16 micrograms/ml) and clavulanate (8 micrograms/ml), alone and in combination in BACTEC medium (Middlebrook 7H12B medium), were determined by high-performance liquid chromatography (HPLC) and bioassay. By HPLC, the half-life of amoxicillin (trihydrate and sodium) in combination with clavulanate in nonradiolabelled 7H12B medium was 6.7 days, whereas the half-life of clavulanate in combination with amoxicillin was 2.0 days. By bioassay, the half-lives of amoxicillin trihydrate and clavulanate in radiolabelled 7H12B medium were comparable (7 and 2 days, respectively) to those determined by HPLC. When clavulanate was tested alone, the half-life was determined to be 1.88 days by HPLC and 1.87 days by bioassay. The relatively short half-life of clavulanate can be adjusted by a procedure of "topping up," or adding one-half the concentration of clavulanate every second day, in order to allow accurate amoxicillin-clavulanate MIC testing with the BACTEC mycobacterial susceptibility system. PMID:8727931

  13. Mink liver TEQs and reproductive NOAEL resulting from dietary exposure to fish from Saginaw Bay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tillitt, D.E.; Gale, R.W.; Peterman, P.H.

    1994-12-31

    Mink are known to be very sensitive to the toxic effects of planar halogenated hydrocarbons (PHHs). Previously the authors reported the reproductive effects in mink fed a diet containing 10, 20, or 40% fish taken from Saginaw Bay, Lake Huron. In this presentation the authors report the complete chemical analyses of the diets and the adult mink livers, along with a comparison of an additive model of toxicity with the results of the H411E bioassay on these samples. The H411E bioassay consistently estimated greater dioxin toxic-equivalents (TEQS) as compared to an additive model of toxicity and chemical analyses. TEQs derivedmore » from chemical analyses accounted for approximately 60% of the TEQs observed with the H411E bioassay. The difference is likely due to the presence of compounds which were not quantitated as opposed to synergistic interactions of the mixtures. Significant reproductive effects were observed in the lowest treatment group (10% fish, or 19.4 pg TEQs/g). The implications of these chemical and bioassay analyses on the calculation of a NOAEL will be discussed.« less

  14. The use of Chironomus riparius larvae to assess effects of pesticides from rice fields in adjacent freshwater ecosystems.

    PubMed

    Faria, Mafalda S; Nogueira, António J A; Soares, Amadeu M V M

    2007-06-01

    A bioassay with Chironomus riparius larvae, using larval development and growth as endpoints, was carried out inside a rice field and in the adjacent wetland channel in Portugal, during pesticide treatments (molinate, endosulfan and propanil) to determine impact caused by pesticide contamination in freshwater ecosystems. The bioassay was also performed under laboratory conditions, to assess whether in situ and laboratory bioassays demonstrated comparable results. Growth was inhibited by concentrations of endosulfan (2.3 and 1.9 microgL(-1) averages) in water from rice field in both the field and laboratory, and by concentrations of endosulfan (0.55 and 0.76 microgL(-1) averages) in water from the wetland channel in the laboratory bioassay, while development was not affected. C. riparius larvae were not affected by molinate and propanil concentrations. The results indicate that endosulfan treatments in rice fields may cause an ecological impairment in adjacent freshwater ecosystems. The results also indicate that laboratory testing can be used to assess in situ toxicity caused by pesticide contamination.

  15. Metallic elements in fossil fuel combustion products: amounts and form of emissions and evaluation of carcinogenicity and mutagenicity.

    PubMed Central

    Vouk, V B; Piver, W T

    1983-01-01

    Metallic elements contained in coal, oil and gasoline are mobilized by combustion processes and may be emitted into the atmosphere, mainly as components of submicron particles. The information about the amounts, composition and form of metal compounds is reviewed for some fuels and combustion processes. Since metal compounds are always contained in urban air pollutants, they have to be considered whenever an evaluation of biological impact of air pollutants is made. The value of currently used bioassays for the evaluation of the role of trace metal compounds, either as major biologically active components or as modifiers of biological effects of organic compounds is assessed. The whole animal bioassays for carcinogenicity do not seem to be an appropriate approach. They are costly, time-consuming and not easily amenable to the testing of complex mixtures. Some problems related to the application and interpretation of short-term bioassays are considered, and the usefulness of such bioassays for the evaluation of trace metal components contained in complex air pollution mixtures is examined. PMID:6337825

  16. Data reduction programs for a laser radar system

    NASA Technical Reports Server (NTRS)

    Badavi, F. F.; Copeland, G. E.

    1984-01-01

    The listing and description of software routines which were used to analyze the analog data obtained from LIDAR - system are given. All routines are written in FORTRAN - IV on a HP - 1000/F minicomputer which serves as the heart of the data acquisition system for the LIDAR program. This particular system has 128 kilobytes of highspeed memory and is equipped with a Vector Instruction Set (VIS) firmware package, which is used in all the routines, to handle quick execution of different long loops. The system handles floating point arithmetic in hardware in order to enhance the speed of execution. This computer is a 2177 C/F series version of HP - 1000 RTE-IVB data acquisition computer system which is designed for real time data capture/analysis and disk/tape mass storage environment.

  17. Urine testing for designer steroids by liquid chromatography with androgen bioassay detection and electrospray quadrupole time-of-flight mass spectrometry identification.

    PubMed

    Nielen, Michel W F; Bovee, Toine F H; van Engelen, Marcel C; Rutgers, Paula; Hamers, Astrid R M; van Rhijn, J Hans A; Hoogenboom, L Ron A P

    2006-01-15

    New anabolic steroids show up occasionally in sports doping and in veterinary control. The discovery of these designer steroids is facilitated by findings of illicit preparations, thus allowing bioactivity testing, structure elucidation using NMR and mass spectrometry, and final incorporation in urine testing. However, as long as these preparations remain undiscovered, new designer steroids are not screened for in routine sports doping or veterinary control urine tests since the established GC/MS and LC/MS/MS methods are set up for the monitoring of a few selected ions or MS/MS transitions of known substances only. In this study, the feasibility of androgen bioactivity testing and mass spectrometric identification is being investigated for trace analysis of designer steroids in urine. Following enzymatic deconjugation and a generic solid-phase extraction, the samples are analyzed by gradient LC with effluent splitting toward two identical 96-well fraction collectors. One well plate is used for androgen bioactivity detection using a novel robust yeast reporter gene bioassay yielding a biogram featuring a 20-s time resolution. The bioactive wells direct the identification efforts to the corresponding well numbers in the duplicate plate. These are subjected to high-resolution LC using a short column packed with 1.7-microm C18 material and coupled with electrospray quadrupole time-of-flight mass spectrometry (LC/QTOFMS) with accurate mass measurement. Element compositions are calculated and used to interrogate electronic substance databases. The feasibility of this approach for doping control is demonstrated via the screening of human urine samples spiked with the designer anabolic steroid tetrahydrogestrinone. Application of the proposed methodology, complementary to the established targeted urine screening for known anabolics, will increase the chance of finding unknown emerging designer steroids, rather then being solely dependent on findings of the illicit preparations themselves.

  18. Comparison of a bioassay and a liquid chromatography-fluorescence-mass spectrometry(n) method for the detection of incurred enrofloxacin residues in chicken tissues.

    PubMed

    Schneider, M J; Donoghue, D J

    2004-05-01

    Regulatory monitoring for most antibiotic residues in edible poultry tissues is often accomplished with accurate, although expensive and technically demanding, chemical analytical techniques. The purpose of this study is to determine if a simple, inexpensive bioassay could detect fluoroquinolone (FQ) residues in chicken muscle above the FDA established tolerance (300 ppb) comparable to a liquid chromatography-fluorescencemass spectrometry(n) method. To produce incurred enrofloxacin (ENRO) tissues (where ENRO is incorporated into complex tissue matrices) for the method comparison, 40-d-old broilers (mixed sex) were orally dosed through drinking water for 3 d at the FDA-approved dose of ENRO (50 ppm). At the end of each day of the 3-d dosing period and for 3 d postdosing, birds were sacrificed and breast and thigh muscle collected and analyzed. Both methods were able to detect ENRO at and below the tolerance level in the muscle, with limits of detection of 26 ppb (bioassay), 0.1 ppb for ENRO, and 0.5 ppb for the ENRO metabolite, ciprofloxacin (liquid chromatography-fluorescence-mass spectrometry(n)). All samples that had violative levels of antibiotic were detected by the bioassay. These results support the use of this bioassay as a screening method for examining large numbers of samples for regulatory monitoring. Positive samples should then be examined by a more extensive method, such as liquid chromatography-fluorescence-mass spectrometry(n), to provide confirmation of the analyte.

  19. Kinetic microplate bioassays for relative potency of antibiotics improved by partial Least Square (PLS) regression.

    PubMed

    Francisco, Fabiane Lacerda; Saviano, Alessandro Morais; Almeida, Túlia de Souza Botelho; Lourenço, Felipe Rebello

    2016-05-01

    Microbiological assays are widely used to estimate the relative potencies of antibiotics in order to guarantee the efficacy, safety, and quality of drug products. Despite of the advantages of turbidimetric bioassays when compared to other methods, it has limitations concerning the linearity and range of the dose-response curve determination. Here, we proposed to use partial least squares (PLS) regression to solve these limitations and to improve the prediction of relative potencies of antibiotics. Kinetic-reading microplate turbidimetric bioassays for apramacyin and vancomycin were performed using Escherichia coli (ATCC 8739) and Bacillus subtilis (ATCC 6633), respectively. Microbial growths were measured as absorbance up to 180 and 300min for apramycin and vancomycin turbidimetric bioassays, respectively. Conventional dose-response curves (absorbances or area under the microbial growth curve vs. log of antibiotic concentration) showed significant regression, however there were significant deviation of linearity. Thus, they could not be used for relative potency estimations. PLS regression allowed us to construct a predictive model for estimating the relative potencies of apramycin and vancomycin without over-fitting and it improved the linear range of turbidimetric bioassay. In addition, PLS regression provided predictions of relative potencies equivalent to those obtained from agar diffusion official methods. Therefore, we conclude that PLS regression may be used to estimate the relative potencies of antibiotics with significant advantages when compared to conventional dose-response curve determination. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Genotoxic risk identification of soil contamination at a major industrialized city in northeast China by a combination of in vitro and in vivo bioassays.

    PubMed

    Xiao, Rui-Yang; Wang, Zijian; Wang, Chun-Xia; Yu, Guo; Zhu, Yong-Guan

    2006-10-01

    The present study evaluated the genotoxicity of field soils in the Tianjin area, one of the most industrialized contaminated areas in northeast China. The genotoxicity of organic extracts of 41 soils was assayed by an in vitro SOS/ umu bioassay with Salmonella typhimurium TA 1535/pSK 1002. From the 41 soil samples, 11 samples were selected to confirm the genotoxic effect by in vivo single-cell gel electrophoresis (comet assay) using earthworms (Eisenia fetida). The results obtained demonstrated that, in the in vitro assay, genotoxicity expressed as induction ratios (IR) ranged from 1.00 to 4.60, and in the in vivo assay, the genotoxicity expressed as tail moment (TM) varied from 14.6 to 57.8 microm. All samples with high genotoxicity assessed by the SOS/umu bioassay possessed significantly high genotoxic effects in the comet assay, and there was a correlation (R2 = 0.736, p < 0.05) between IR and TM in both bioassays. It is concluded that soils in the Tianjin area were seriously contaminated by organic genotoxicants and higher levels of genotoxic effects existed in soils in the urban area of Tianjin as well as in areas near the coastal towns in the northeast part of the city. It can be concluded that a combination of in vivo and in vitro bioassays as a powerful and efficient genotoxicity-assessing tool could facilitate the assessment of genotoxic risk at a regional scale.

  1. Activities of Jatropha curcas phorbol esters in various bioassays.

    PubMed

    Devappa, Rakshit K; Rajesh, Sanjay K; Kumar, Vikas; Makkar, Harinder P S; Becker, Klaus

    2012-04-01

    Jatropha curcas seeds contain 30-35% oil, which can be converted to high quality biodiesel. However, Jatropha oil is toxic, ascribed to the presence of phorbol esters (PEs). In this study, isolated phorbol ester rich fraction (PEEF) was used to evaluate the activity of PEs using three aquatic species based bioassays (snail (Physa fontinalis), brine shrimp (Artemeia salina), daphnia (Daphnia magna)) and microorganisms. In all the bioassays tested, increase in concentration of PEs increased mortality with an EC(50) (48 h) of 0.33, 26.48 and 0.95 mg L(-1) PEs for snail, artemia and daphnia, respectively. The sensitivity of various microorganisms for PEs was also tested. Among the bacterial species tested, Streptococcus pyogenes and Proteus mirabilis were highly susceptible with a minimum inhibitory concentration (MIC) of 215 mg L(-1) PEs; and Pseudomonas putida were also sensitive with MIC of 251 mg L(-1) PEs. Similarly, Fusarium species of fungi exhibited EC(50) of 58 mg L(-1) PEs, while Aspergillus niger and Curvularia lunata had EC(50) of 70 mg L(-1). The snail bioassay was most sensitive with 100% snail mortality at 1 μg of PEs mL(-1). In conclusion, snail bioassay could be used to monitor PEs in Jatropha derived products such as oil, biodiesel, fatty acid distillate, kernel meal, cake, glycerol or for contamination in soil or other environmental matrices. In addition, PEs with molluscicidal/antimicrobial activities could be utilized for agricultural and pharmaceutical applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Ectomycorrhizal fungal spore bank recovery after a severe forest fire: some like it hot.

    PubMed

    Glassman, Sydney I; Levine, Carrie R; DiRocco, Angela M; Battles, John J; Bruns, Thomas D

    2016-05-01

    After severe wildfires, pine recovery depends on ectomycorrhizal (ECM) fungal spores surviving and serving as partners for regenerating forest trees. We took advantage of a large, severe natural forest fire that burned our long-term study plots to test the response of ECM fungi to fire. We sampled the ECM spore bank using pine seedling bioassays and high-throughput sequencing before and after the California Rim Fire. We found that ECM spore bank fungi survived the fire and dominated the colonization of in situ and bioassay seedlings, but there were specific fire adapted fungi such as Rhizopogon olivaceotinctus that increased in abundance after the fire. The frequency of ECM fungal species colonizing pre-fire bioassay seedlings, post-fire bioassay seedlings and in situ seedlings were strongly positively correlated. However, fire reduced the ECM spore bank richness by eliminating some of the rare species, and the density of the spore bank was reduced as evidenced by a larger number of soil samples that yielded uncolonized seedlings. Our results show that although there is a reduction in ECM inoculum, the ECM spore bank community largely remains intact, even after a high-intensity fire. We used advanced techniques for data quality control with Illumina and found consistent results among varying methods. Furthermore, simple greenhouse bioassays can be used to determine which fungi will colonize after fires. Similar to plant seed banks, a specific suite of ruderal, spore bank fungi take advantage of open niche space after fires.

  3. Third-generation Ah receptor-responsive luciferase reporter plasmids: amplification of dioxin-responsive elements dramatically increases CALUX bioassay sensitivity and responsiveness.

    PubMed

    He, Guochun; Tsutsumi, Tomoaki; Zhao, Bin; Baston, David S; Zhao, Jing; Heath-Pagliuso, Sharon; Denison, Michael S

    2011-10-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related dioxin-like chemicals are widespread and persistent environmental contaminants that produce diverse toxic and biological effects through their ability to bind to and activate the Ah receptor (AhR) and AhR-dependent gene expression. The chemically activated luciferase expression (CALUX) system is an AhR-responsive recombinant luciferase reporter gene-based cell bioassay that has been used in combination with chemical extraction and cleanup methods for the relatively rapid and inexpensive detection and relative quantitation of dioxin and dioxin-like chemicals in a wide variety of sample matrices. Although the CALUX bioassay has been validated and used extensively for screening purposes, it has some limitations when screening samples with very low levels of dioxin-like chemicals or when there is only a small amount of sample matrix for analysis. Here, we describe the development of third-generation (G3) CALUX plasmids with increased numbers of dioxin-responsive elements, and stable transfection of these new plasmids into mouse hepatoma (Hepa1c1c7) cells has produced novel amplified G3 CALUX cell bioassays that respond to TCDD with a dramatically increased magnitude of luciferase induction and significantly lower minimal detection limit than existing CALUX-type cell lines. The new G3 CALUX cell lines provide a highly responsive and sensitive bioassay system for the detection and relative quantitation of very low levels of dioxin-like chemicals in sample extracts.

  4. Ectomycorrhizal fungal spore bank recovery after a severe forest fire: some like it hot

    PubMed Central

    Glassman, Sydney I; Levine, Carrie R; DiRocco, Angela M; Battles, John J; Bruns, Thomas D

    2016-01-01

    After severe wildfires, pine recovery depends on ectomycorrhizal (ECM) fungal spores surviving and serving as partners for regenerating forest trees. We took advantage of a large, severe natural forest fire that burned our long-term study plots to test the response of ECM fungi to fire. We sampled the ECM spore bank using pine seedling bioassays and high-throughput sequencing before and after the California Rim Fire. We found that ECM spore bank fungi survived the fire and dominated the colonization of in situ and bioassay seedlings, but there were specific fire adapted fungi such as Rhizopogon olivaceotinctus that increased in abundance after the fire. The frequency of ECM fungal species colonizing pre-fire bioassay seedlings, post-fire bioassay seedlings and in situ seedlings were strongly positively correlated. However, fire reduced the ECM spore bank richness by eliminating some of the rare species, and the density of the spore bank was reduced as evidenced by a larger number of soil samples that yielded uncolonized seedlings. Our results show that although there is a reduction in ECM inoculum, the ECM spore bank community largely remains intact, even after a high-intensity fire. We used advanced techniques for data quality control with Illumina and found consistent results among varying methods. Furthermore, simple greenhouse bioassays can be used to determine which fungi will colonize after fires. Similar to plant seed banks, a specific suite of ruderal, spore bank fungi take advantage of open niche space after fires. PMID:26473720

  5. Application of the automated spatial surveillance program to birth defects surveillance data.

    PubMed

    Gardner, Bennett R; Strickland, Matthew J; Correa, Adolfo

    2007-07-01

    Although many birth defects surveillance programs incorporate georeferenced records into their databases, practical methods for routine spatial surveillance are lacking. We present a macroprogram written for the software package R designed for routine exploratory spatial analysis of birth defects data, the Automated Spatial Surveillance Program (ASSP), and present an application of this program using spina bifida prevalence data for metropolitan Atlanta. Birth defects surveillance data were collected by the Metropolitan Atlanta Congenital Defects Program. We generated ASSP maps for two groups of years that correspond roughly to the periods before (1994-1998) and after (1999-2002) folic acid fortification of flour. ASSP maps display census tract-specific spina bifida prevalence, smoothed prevalence contours, and locations of statistically elevated prevalence. We used these maps to identify areas of elevated prevalence for spina bifida. We identified a large area of potential concern in the years following fortification of grains and cereals with folic acid. This area overlapped census tracts containing large numbers of Hispanic residents. The potential utility of ASSP for spatial disease monitoring was demonstrated by the identification of areas of high prevalence of spina bifida and may warrant further study and monitoring. We intend to further develop ASSP so that it becomes practical for routine spatial monitoring of birth defects. (c) 2007 Wiley-Liss, Inc.

  6. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM TECHNOLOGY PROFILES: SIXTH EDITION

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new and promising treatment and monitoring and measurement technologies for cleanup of hazardous waste sites. The program was created to encourage the development and routine use of innovative treatment techn...

  7. SUPERFUND INNOVATIVE TECHNOLOGY EVALUATION PROGRAM - TECHNOLOGY PROFILES - SEVENTH EDITION

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new and promising treatment and monitoring and measurement technologies for cleanup of hazardous waste sites. The program was created to encourage the development and routine use of innovative treatment techn...

  8. Sustainability of the good behaviour game in Dutch primary schools.

    PubMed

    Dijkman, Marieke A M; Harting, Janneke; van Tol, Lenneke; van der Wal, Marcel F

    2017-02-01

    Sustainability of health promotion programs is essential to maintain their positive effects. However, few studies have examined the extent of program sustainability and the factors influencing it. We examined these issues through the Good Behaviour Game (GBG), a classroom-based program in primary schools with beneficial behavioural and health-related effects that was implemented in 2008. GBG coordinators of 17 participating schools were invited in the study 2 years after the initial program implementation. Sustainability was measured using a 20-item checklist comprised of four dimensions of routinization including: memory, adaptation, values and rules. A semi-structured interview was then completed with 16 of the GBG coordinators to discuss the checklist scores and to probe in more depth the current level of sustainability. Based on the checklist scores, sustainability of the GBG was considered ‘high’ in five schools, ‘medium’ in another five and ‘weak’ in six. Factors influencing sustainability identified by GBG coordinators were organizational strength, strong leadership, program championship and the perceived modifiability and effectiveness of the GBG. Also, different factors were related to different dimensions of routinization. The combination of a sustainability checklist and an interview about influential factors may help to further clarify the sustainability construct and reveal which implementation sites, routinization dimensions and influential factors should be explored to further facilitate the sustaining of programs with proven effectiveness.

  9. Infectivity of porcine circovirus type 2 DNA in semen from experimentally-infected boars

    PubMed Central

    Madson, Darin M.; Ramamoorthy, Sheela; Kuster, Chris; Pal, Narinder; Meng, Xiang-Jin; Halbur, Patrick G.; Opriessnig, Tanja

    2009-01-01

    Porcine circovirus type 2 (PCV2) is an economically important pathogen. It has been demonstrated that PCV2 DNA can be detected in boar semen by PCR; however, the biological relevance of this is unknown. The objectives of this study were to determine if semen positive for PCV2 DNA is infectious (1) in a swine bioassay, or (2) when used for artificial insemination. For the first objective, 4-week-old pigs were inoculated intraperitoneally with PCV2 DNA-negative (bioassay-control; n = 3), PCV2a DNA-positive (bioassay-PCV2a; n = 3), or PCV2b DNA-positive (bioassay-PCV2b; n = 3) raw semen, or PCV2 live virus (bioassay-positive; n = 3), respectively. Pigs inoculated with PCV2 DNA-positive semen and PCV2 live virus became viremic and developed anti-PCV2 antibodies indicating that the PCV2 DNA present in semen was infectious. For the second objective, three Landrace gilts were inseminated with PCV2 DNA-negative semen (gilts-controls) from experimentally-infected boars, and six gilts were artificially inseminated with semen positive for PCV2a DNA (gilts-PCV2a; n = 3) or PCV2b DNA (gilts-PCV2b; n = 3). Serum samples collected from the gilts in all groups remained negative for anti-PCV2 antibodies for the duration of the experiment. In addition, fetal serum samples from all 105-day-gestation fetuses were negative for anti-PCV2 antibodies or PCV2 DNA. Under the conditions of this study, PCV2 DNA-positive semen was not infectious when used to artificially inseminate gilts; however, it was demonstrated to be infectious in a swine bioassay model and therefore is a potential means of PCV2 transmission amongst swine herds. PMID:18973743

  10. Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses

    NASA Astrophysics Data System (ADS)

    Stefansson, E. S.

    2008-12-01

    Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must be removed and disposed of properly, in order to make future piling removals as effective and beneficial to ecosystem health as possible.

  11. Scientific Considerations for Evaluating Cancer Bioassays Conducted by the Ramazzini Institute

    PubMed Central

    Caldwell, Jane C.; Jinot, Jennifer; Evans, Marina V.; Cote, Ila; Vandenberg, John J.

    2013-01-01

    Background: The Ramazzini Institute (RI) has completed nearly 400 cancer bioassays on > 200 compounds. The European Food Safety Authority (EFSA) and others have suggested that study design and protocol differences between the RI and other laboratories by may contribute to controversy regarding cancer hazard findings, principally findings on lymphoma/leukemia diagnoses. Objective: We aimed to evaluate RI study design, protocol differences, and accuracy of tumor diagnoses for their impact on carcinogenic hazard characterization. Methods: We analyzed the findings from a recent Pathology Working Group (PWG) review of RI procedures and tumor diagnoses, evaluated consistency of RI and other laboratory findings for chemicals identified by the RI as positive for lymphoma/leukemia, and examined evidence for a number of other issues raised regarding RI bioassays. The RI cancer bioassay design and protocols were evaluated in the context of relevant risk assessment guidance from international authorities. Discussion: Although the PWG identified close agreement with RI diagnoses for most tumor types, it did not find close agreement for lymphoma/leukemia of the respiratory tract or for neoplasms of the inner ear and cranium. Here we discuss a) the implications of the PWG findings, particularly lymphoma diagnostic issues; b) differences between RI studies and those from other laboratories that are relevant to evaluating RI cancer bioassays; and c) future work that may help resolve some concerns. Conclusions: We concluded that a) issues related to respiratory tract infections have complicated diagnoses at that site (i.e., lymphoma/leukemia), as well as for neoplasms of the inner ear and cranium, and b) there is consistency and value in RI studies for identification of other chemical-related neoplasia. Citation: Gift JS, Caldwell JC, Jinot J, Evans MV, Cote I, Vandenberg JJ. 2013. Scientific considerations for evaluating cancer bioassays conducted by the Ramazzini Institute. Environ Health Perspect 121:1253–1263; http://dx.doi.org/10.1289/ehp.1306661 PMID:24045135

  12. Effect-based trigger values for in vitro and in vivo bioassays performed on surface water extracts supporting the environmental quality standards (EQS) of the European Water Framework Directive.

    PubMed

    Escher, Beate I; Aїt-Aїssa, Selim; Behnisch, Peter A; Brack, Werner; Brion, François; Brouwer, Abraham; Buchinger, Sebastian; Crawford, Sarah E; Du Pasquier, David; Hamers, Timo; Hettwer, Karina; Hilscherová, Klára; Hollert, Henner; Kase, Robert; Kienle, Cornelia; Tindall, Andrew J; Tuerk, Jochen; van der Oost, Ron; Vermeirssen, Etienne; Neale, Peta A

    2018-07-01

    Effect-based methods including cell-based bioassays, reporter gene assays and whole-organism assays have been applied for decades in water quality monitoring and testing of enriched solid-phase extracts. There is no common EU-wide agreement on what level of bioassay response in water extracts is acceptable. At present, bioassay results are only benchmarked against each other but not against a consented measure of chemical water quality. The EU environmental quality standards (EQS) differentiate between acceptable and unacceptable surface water concentrations for individual chemicals but cannot capture the thousands of chemicals in water and their biological action as mixtures. We developed a method that reads across from existing EQS and includes additional mixture considerations with the goal that the derived effect-based trigger values (EBT) indicate acceptable risk for complex mixtures as they occur in surface water. Advantages and limitations of various approaches to read across from EQS are discussed and distilled to an algorithm that translates EQS into their corresponding bioanalytical equivalent concentrations (BEQ). The proposed EBT derivation method was applied to 48 in vitro bioassays with 32 of them having sufficient information to yield preliminary EBTs. To assess the practicability and robustness of the proposed approach, we compared the tentative EBTs with observed environmental effects. The proposed method only gives guidance on how to derive EBTs but does not propose final EBTs for implementation. The EBTs for some bioassays such as those for estrogenicity are already mature and could be implemented into regulation in the near future, while for others it will still take a few iterations until we can be confident of the power of the proposed EBTs to differentiate good from poor water quality with respect to chemical contamination. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Comparison of the standard WHO susceptibility tests and the CDC bottle bioassay for the determination of insecticide susceptibility in malaria vectors and their correlation with biochemical and molecular biology assays in Benin, West Africa.

    PubMed

    Aïzoun, Nazaire; Ossè, Razaki; Azondekon, Roseric; Alia, Roland; Oussou, Olivier; Gnanguenon, Virgile; Aikpon, Rock; Padonou, Gil Germain; Akogbéto, Martin

    2013-05-20

    The detection of insecticide resistance in natural populations of Anopheles vectors is absolutely necessary for malaria control. In the African region, the WHO insecticide susceptibility test is the most common method for assessing resistance status. In order to search for a simple, rapid and more reliable technique in the assessment of insecticide resistance in malaria vectors, we compared the WHO tests with the CDC bottle bioassay in the Ouemé province of southern Benin where insecticide resistance has been widely reported. Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Ouemé. WHO and CDC susceptibility tests were conducted simultaneously on unfed female mosquitoes aged 2-5 days old. WHO bioassays were performed with impregnated papers of deltamethrin (0.05%) and bendiocarb (0.1%), whereas CDC bioassays were performed with stock solutions of deltamethrin (12.5 μg per bottle) and bendiocarb (12.5 μg per bottle). PCR techniques were used to detect species, Kdr and Ace-1 mutations. CDC biochemical assays using synergists were also conducted to assess the metabolic resistance. A slight decrease in mortality rates was observed with 97.95% and 98.33% obtained from CDC and WHO bioassays respectively in populations of mosquitoes from Adjara and Dangbo. PCR revealed that all specimens tested were Anopheles gambiae s.s. The Kdr mutation was found at high frequency in all populations and both the Kdr mutation and mono-oxygenase enzymes were implicated as mechanisms of pyrethroid resistance in An. gambiae from Misserete. This study emphasizes that both WHO and CDC bioassays give similar results with regards to the susceptibility of mosquitoes to insecticides in southern Benin. There were complementarities between both methods, however, some specificity was noted for each of the two methods used. Both Kdr and metabolic mechanisms were implicated in the resistance.

  14. Evaluating the efficacy of biological and conventional insecticides with the new 'MCD bottle' bioassay.

    PubMed

    Sternberg, Eleanore D; Waite, Jessica L; Thomas, Matthew B

    2014-12-16

    Control of mosquitoes requires the ability to evaluate new insecticides and to monitor resistance to existing insecticides. Monitoring tools should be flexible and low cost so that they can be deployed in remote, resource poor areas. Ideally, a bioassay should be able to simulate transient contact between mosquitoes and insecticides, and it should allow for excito-repellency and avoidance behaviour in mosquitoes. Presented here is a new bioassay, which has been designed to meet these criteria. This bioassay was developed as part of the Mosquito Contamination Device (MCD) project and, therefore, is referred to as the MCD bottle bioassay. Presented here are two experiments that serve as a proof-of-concept for the MCD bottle bioassay. The experiments used four insecticide products, ranging from fast-acting, permethrin-treated, long-lasting insecticide nets (LLINs) that are already widely used for malaria vector control, to the slower acting entomopathogenic fungus, Beauveria bassiana, that is currently being evaluated as a prospective biological insecticide. The first experiment used the MCD bottle to test the effect of four different insecticides on Anopheles stephensi with a range of exposure times (1 minute, 3 minutes, 1 hour). The second experiment is a direct comparison of the MCD bottle and World Health Organization (WHO) cone bioassay that tests a subset of the insecticides (a piece of LLIN and a piece of netting coated with B. bassiana spores) and a further reduced exposure time (5 seconds) against both An. stephensi and Anopheles gambiae. Immediate knockdown and mortality after 24 hours were assessed using logistic regression and daily survival was assessed using Cox proportional hazards models. Across both experiments, fungus performed much more consistently than the chemical insecticides but measuring the effect of fungus required monitoring of mosquito mortality over several days to a week. Qualitatively, the MCD bottle and WHO cone performed comparably, although knockdown and 24 hour mortality tended to be higher in some, but not all, groups of mosquitoes exposed using the WHO cone. The MCD bottle is feasible as a flexible, low-cost method for testing insecticidal materials. It is promising as a tool for testing transient contact and for capturing the effects of mosquito behavioural responses to insecticides.

  15. Quantitative risk assessment for a glass fiber insulation product.

    PubMed

    Fayerweather, W E; Bender, J R; Hadley, J G; Eastes, W

    1997-04-01

    California Proposition 65 (Prop65) provides a mechanism by which the manufacturer may perform a quantitative risk assessment to be used in determining the need for cancer warning labels. This paper presents a risk assessment under this regulation for professional and do-it-yourself insulation installers. It determines the level of insulation glass fiber exposure (specifically Owens Corning's R-25 PinkPlus with Miraflex) that, assuming a working lifetime exposure, poses no significant cancer risk under Prop65's regulations. "No significant risk" is defined under Prop65 as a lifetime risk of no more than one additional cancer case per 100,000 exposed persons, and nonsignificant exposure is defined as a working lifetime exposure associated with "no significant risk." This determination can be carried out despite the fact that the relevant underlying studies (i.e., chronic inhalation bioassays) of comparable glass wool fibers do not show tumorigenic activity. Nonsignificant exposures are estimated from (1) the most recent RCC chronic inhalation bioassay of nondurable fiberglass in rats; (2) intraperitoneal fiberglass injection studies in rats; (3) a distributional, decision analysis approach applied to four chronic inhalation rat bioassays of conventional fiberglass; (4) an extrapolation from the RCC chronic rat inhalation bioassay of durable refractory ceramic fibers; and (5) an extrapolation from the IOM chronic rat inhalation bioassay of durable E glass microfibers. When the EPA linear nonthreshold model is used, central estimates of nonsignificant exposure range from 0.36 fibers/cc (for the RCC chronic inhalation bioassay of fiberglass) through 21 fibers/cc (for the i.p. fiberglass injection studies). Lower 95% confidence bounds on these estimates vary from 0.17 fibers/cc through 13 fibers/cc. Estimates derived from the distributional approach or from applying the EPA linear nonthreshold model to chronic bioassays of durable fibers such as refractory ceramic fiber or E glass microfibers are intermediate to the other approaches. Estimates based on the Weibull 1.5-hit nonthreshold and 2-hit threshold models exceed by at least a factor of 10 the corresponding EPA linear nonthreshold estimates. The lowest nonsignificant exposures derived in this assessment are at least a factor of two higher than field exposures measured for professionals installing the R-25 fiberglass insulation product and are orders of magnitude higher than the estimated lifetime exposures for do-it-yourselfers.

  16. SRB-3D Solid Rocket Booster performance prediction program. Volume 3: Programmer's manual

    NASA Technical Reports Server (NTRS)

    Winkler, J. C.

    1976-01-01

    The programmer's manual for the Modified Solid Rocket Booster Performance Prediction Program (SRB-3D) describes the major control routines of SRB-3D, followed by a super index listing of the program and a cross-reference of the program variables.

  17. The antibacterial effects of silver, titanium dioxide and silica dioxide nanoparticles compared to the dental disinfectant chlorhexidine on Streptococcus mutans using a suite of bioassays

    PubMed Central

    Besinis, Alexandros; De Peralta, Tracy

    2014-01-01

    Metal-containing nanomaterials have the potential to be used in dentistry for infection control, but little is known about their antibacterial properties. This study investigated the toxicity of silver (Ag), titanium dioxide and silica nanoparticles (NPs) against the oral pathogenic species of Streptococcus mutans, compared to the routine disinfectant, chlorhexidine. The bacteria were assessed using the minimum inhibitory concentration assay for growth, fluorescent staining for live/dead cells, and measurements of lactate. All the assays showed that Ag NPs had the strongest antibacterial activity of the NPs tested, with bacterial growth also being 25-fold lower than that in chlorhexidine. The survival rate of bacteria under the effect of 100 mg l−1 Ag NPs in the media was 2% compared to 60% with chlorhexidine, while the lactate concentration was 0.6 and 4.0 mM, respectively. Silica and titanium dioxide NPs had limited effects. Dialysis experiments showed negligible silver dissolution. Overall, Ag NPs were the best disinfectant and performed better than chlorhexidine. Improvements to the MIC assay are suggested. PMID:23092443

  18. A new bioseed for determination of wastewater biodegradability: analysis of the experimental procedure.

    PubMed

    Ballesteros Martín, M M; Esteban García, B; Ortega-Gómez, E; Sánchez Pérez, J A

    2014-01-01

    A new bioassay proposed in the patent P201300029 was applied to a pre-treated wastewater containing a mixture of commercial pesticides to simulate a recalcitrant industrial wastewater in order to determine its biodegradability. The test uses a mixture of standardized inoculum of the lyophilized bacteria Pseudomonas putida with the proper proportion of salts and minerals. The results highlight that biodegradation efficiency can be calculated using a gross parameter (chemical oxygen demand (COD)) which facilitates the biodegradability determination for routine water biodegradability analysis. The same trend was observed throughout the assay with the dehydrated and fresh inoculums, and only a difference of 5% in biodegradation efficiency (E f) was observed. The obtained results showed that the P. putida biodegradability assay can be used as a commercial test with a lyophilized inoculum in order to monitor the ready biodegradability of an organic pollutant or a WWTP influent. Moreover, a combination of the BOD5/COD ratio and the P. putida biodegradability test is an attractive alternative in order to evaluate the biodegradability enhancement in water pre-treated with advanced oxidation processes (AOPs).

  19. Application of in vitro cell transformation assays in regulatory toxicology for pharmaceuticals, chemicals, food products and cosmetics.

    PubMed

    Vanparys, Philippe; Corvi, Raffaella; Aardema, Marilyn J; Gribaldo, Laura; Hayashi, Makoto; Hoffmann, Sebastian; Schechtman, Leonard

    2012-04-11

    Two year rodent bioassays play a key role in the assessment of carcinogenic potential of chemicals to humans. The seventh amendment to the European Cosmetics Directive will ban in 2013 the marketing of cosmetic and personal care products that contain ingredients that have been tested in animal models. Thus 2-year rodent bioassays will not be available for cosmetics/personal care products. Furthermore, for large testing programs like REACH, in vivo carcinogenicity testing is impractical. Alternative ways to carcinogenicity assessment are urgently required. In terms of standardization and validation, the most advanced in vitro tests for carcinogenicity are the cell transformation assays (CTAs). Although CTAs do not mimic the whole carcinogenesis process in vivo, they represent a valuable support in identifying transforming potential of chemicals. CTAs have been shown to detect genotoxic as well as non-genotoxic carcinogens and are helpful in the determination of thresholds for genotoxic and non-genotoxic carcinogens. The extensive review on CTAs by the OECD (OECD (2007) Environmental Health and Safety Publications, Series on Testing and Assessment, No. 31) and the proven within- and between-laboratories reproducibility of the SHE CTAs justifies broader use of these methods to assess carcinogenic potential of chemicals. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Overview of ToxCast™ | Science Inventory | US EPA

    EPA Pesticide Factsheets

    In 2007, EPA launched ToxCast™ in order to develop a cost-effective approach for prioritizing the toxicity testing of large numbers of chemicals in a short period of time. Using data from state-of-the-art high throughput screening (HTS) bioassays developed in the pharmaceutical industry, ToxCast™ is building computational models to forecast the potential human toxicity of chemicals. These hazard predictions will provide EPA regulatory programs with science-based information helpful in prioritizing chemicals for more detailed toxicological evaluations, and lead to more efficient use of animal testing. In its first phase, ToxCast™ is profiling over 300 well-characterized chemicals (primarily pesticides) in over 400 HTS endpoints. These endpoints include biochemical assays of protein function, cell-based transcriptional reporter assays, multi-cell interaction assays, transcriptomics on primary cell cultures, and developmental assays in zebrafish embryos. Almost all of the compounds being examined in Phase 1 of ToxCast™ have been tested in traditional toxicology tests, including developmental toxicity, multi-generation studies, and sub-chronic and chronic rodent bioassays. ToxRefDB, a relational database being created to house this information, will contain nearly $1B worth of toxicity studies in animals when completed. ToxRefDB is integrated into a more comprehensive data management system developed by NCCT called ACToR (Aggregated Computational Toxicology

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