WorldWideScience

Sample records for bioassay

  1. UNIFYING SCALER FOR BIOASSAY TESTS

    Science.gov (United States)

    An extensive set of interlaboratory root bioassay data was unified using centroids of individual tests as scalers. It is shown that the dose response obeys a first order differential equation with the constant of the equation related to the sensitivity of the dose response relati...

  2. 77 FR 14837 - Bioassay at Uranium Mills

    Science.gov (United States)

    2012-03-13

    ... COMMISSION Bioassay at Uranium Mills AGENCY: Nuclear Regulatory Commission. ACTION: Draft regulatory guide... for public comment draft regulatory guide (DG), DG-8051, ``Bioassay at Uranium Mills.'' This guide describes a bioassay program acceptable to the NRC staff for uranium mills and applicable portions...

  3. Virtual screening of bioassay data

    Directory of Open Access Journals (Sweden)

    Schierz Amanda C

    2009-12-01

    Full Text Available Abstract Background There are three main problems associated with the virtual screening of bioassay data. The first is access to freely-available curated data, the second is the number of false positives that occur in the physical primary screening process, and finally the data is highly-imbalanced with a low ratio of Active compounds to Inactive compounds. This paper first discusses these three problems and then a selection of Weka cost-sensitive classifiers (Naive Bayes, SVM, C4.5 and Random Forest are applied to a variety of bioassay datasets. Results Pharmaceutical bioassay data is not readily available to the academic community. The data held at PubChem is not curated and there is a lack of detailed cross-referencing between Primary and Confirmatory screening assays. With regard to the number of false positives that occur in the primary screening process, the analysis carried out has been shallow due to the lack of cross-referencing mentioned above. In six cases found, the average percentage of false positives from the High-Throughput Primary screen is quite high at 64%. For the cost-sensitive classification, Weka's implementations of the Support Vector Machine and C4.5 decision tree learner have performed relatively well. It was also found, that the setting of the Weka cost matrix is dependent on the base classifier used and not solely on the ratio of class imbalance. Conclusions Understandably, pharmaceutical data is hard to obtain. However, it would be beneficial to both the pharmaceutical industry and to academics for curated primary screening and corresponding confirmatory data to be provided. Two benefits could be gained by employing virtual screening techniques to bioassay data. First, by reducing the search space of compounds to be screened and secondly, by analysing the false positives that occur in the primary screening process, the technology may be improved. The number of false positives arising from primary screening leads to

  4. A Shrinkage Estimator for Combination of Bioassays

    Institute of Scientific and Technical Information of China (English)

    Jian Xiong; D.G. Chen; Zhen-hai Yang

    2007-01-01

    A shrinkage estimator and a maximum likelihood estimator are proposed in this paper for combination of bioassays. The shrinkage estimator is obtained in closed form which incorporates prior information just on the common log relative potency after the homogeneity test for combination of bioassays is accepted. It is a practical improvement over other estimators which require iterative procedure to obtain the estimator for the relative potency. A real data is also used to show the superiorities for the newly-proposed procedures.

  5. Bioassay criteria for environmental restoration workers

    International Nuclear Information System (INIS)

    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 or 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.)

  6. A Colorimetric Bioassay for Perchlorate

    Science.gov (United States)

    Heinnickel, M. L.; Smith, S.; Coates, J. D.

    2007-12-01

    Recognition of perchlorate (ClO4-) as a widespread contaminant across the United States and its potential adverse affects towards human health has motivated the EPA to place ClO4- on its contaminant candidate list for drinking water supplies. While a federal MCL has not yet been set, a recommended public health goal of 1 ppb (μg.L-1) was established by the US EPA in 2002. To date, methods of detection require use of sensitive ion chromatographic equipment that are expensive, time consuming, and require highly trained personnel for use. Our studies are focused on the development of a highly sensitive, simple, and robust colorimetric bioassay based on the primary enzyme involved in microbial ClO4- reduction, the perchlorate reductase (Pcr). A previously published assay used reduced methyl viologen (MV, the dye is reduced with sodium hydrosulfite) as an electron donor to demonstrate Pcr activity. The assay directly correlates the amount of MV oxidized with the amount of ClO4- reduced by assuming a transfer of four electrons. To test this assumption, we compared actual concentrations of MV oxidized to ClO4- reduced in this assay. ClO4- concentrations were determined using a Dionex ICS-500 ion chromatography system, while MV concentrations were determined using a standard curve generated at 578 nm. Comparisons between the two revealed that twelve molecules of MV were oxidized for each molecule of ClO4- reduced. The oxidation of these additional eight MV molecules is explained by the interaction of the dye with chlorite (the product of the Pcr reaction) and other contaminants that could be present in the enzyme prep. This unsettling result indicated this assay would be problematic for the detection of ClO4- in soil, which has many chemicals that could react with MV. To improve upon this assay, we have tried to reduce ClO4- using less reactive dyes and reductants. The reductants ascorbic acid, NADH, and dithiothreitol drive Pcr catalyzed ClO4- reduction, however, they

  7. Soil bioassays and the 129I problem

    International Nuclear Information System (INIS)

    Iodine-129 is a very long-lived radionuclide associated with spent nuclear fuel. Because 129I has a 107-year half-life, is very mobile in the environment and is a biologically essential element, it is the most limiting radionuclide affecting disposal of spent fuel. Traditionally, the potential impacts of 129I have been estimated for human receptors, with the implicit assumption that all other organisms are less at risk. Risk is the operative word, the objective for protection of humans is to protect individuals, whereas the objective for other biota is usually to protect populations. Here, 129I poses an interesting problem: the half-life is so long it is barely radioactive. Thus, the chemical toxicity may be more limiting than the radiological impact. A series of soil bioassays were employed, including a life-cycle plant (Brassica rapa) bioassay, a modified earthworm survival bioassay, a microarthropod colonization/survival bioassay, and a series of more common soil and aquatic bioassays. Chemical toxicity was indicated at soil concentrations as low as 5 mg kg-1. At these levels, radiological impact on non-human biota would not be expected, and therefore the chemical toxicity effects are more critical. However, human food-chain model estimates show these levels, as pure 129I, would be unacceptable for human radiological exposure, so that for 129I, protection of the human environment should also be protective of non-human biota

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

    Science.gov (United States)

    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.

  9. A Nisin Bioassay Based on Bioluminescence

    OpenAIRE

    Wahlström, G.; Saris, P. E. J.

    1999-01-01

    A Lactococcus lactis subsp. lactis strain that can sense the bacteriocin nisin and transduce the signal into bioluminescence was constructed. By using this strain, a bioassay based on bioluminescence was developed for quantification of nisin, for detection of nisin in milk, and for identification of nisin-producing strains. As little as 0.0125 ng of nisin per ml was detected within 3 h by this bioluminescence assay. This detection limit was lower than in previously described methods.

  10. A Multichannel Bioluminescence Determination Platform for Bioassays.

    Science.gov (United States)

    Kim, Sung-Bae; Naganawa, Ryuichi

    2016-01-01

    The present protocol introduces a multichannel bioluminescence determination platform allowing a high sample throughput determination of weak bioluminescence with reduced standard deviations. The platform is designed to carry a multichannel conveyer, an optical filter, and a mirror cap. The platform enables us to near-simultaneously determine ligands in multiple samples without the replacement of the sample tubes. Furthermore, the optical filters beneath the multichannel conveyer are designed to easily discriminate colors during assays. This optical system provides excellent time- and labor-efficiency to users during bioassays. PMID:27424912

  11. SINGLE LABORATORY EVALUATION OF THE HYDROGEN OXIDATION SOIL BIOASSAY

    Science.gov (United States)

    The Hydrogen Oxidation Soil Bioassay was single laboratory tested as a potential method for monitoring hazardous wastes and hazardous waste sites. The bioassay is based on the rate of hydrogen consumption by soil microorganisms. Oxidation of hydrogen to water is inhibited when va...

  12. Cell-based bioassays in microfluidic systems

    Science.gov (United States)

    Itle, Laura J.; Zguris, Jeanna C.; Pishko, Michael V.

    2004-12-01

    The development of cell-based bioassays for high throughput drug screening or the sensing of biotoxins is contingent on the development of whole cell sensors for specific changes in intracellular conditions and the integration of those systems into sample delivery devices. Here we show the feasibility of using a 5-(and-6)-carboxy SNARF-1, acetoxymethyl ester, acetate, a fluorescent dye capable of responding to changes in intracellular pH, as a detection method for the bacterial endotoxin, lipopolysaccharide. We used photolithography to entrap cells with this dye within poly(ethylene) glyocol diacrylate hydrogels in microfluidic channels. After 18 hours of exposure to lipopolysaccharide, we were able to see visible changes in the fluorescent pattern. This work shows the feasibility of using whole cell based biosensors within microfluidic networks to detect cellular changes in response to exogenous agents.

  13. Information for establishing bioassay measurements and evaluations of tritium exposure

    International Nuclear Information System (INIS)

    This report summarizes information and references used in developing regulatory guidance on programs for the bioassay of tritium as well as information useful in planning and conducting tritium bioassay programs and evaluating bioassay data. A review of literature on tritium radiobiology is included to provide a ready source of information useful for estimating internal doses of tritium and risks for the various tritium compounds and forms, including elemental (gaseous) tritium. Simplified and conservative dose conversion factors are derived and tabulated for easy reference in program planning, safety evaluations, and compliance determinations

  14. Information for establishing bioassay measurements and evaluations of tritium exposure

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, A.

    1983-06-01

    This report summarizes information and references used in developing regulatory guidance on programs for the bioassay of tritium as well as information useful in planning and conducting tritium bioassay programs and evaluating bioassay data. A review of literature on tritium radiobiology is included to provide a ready source of information useful for estimating internal doses of tritium and risks for the various tritium compounds and forms, including elemental (gaseous) tritium. Simplified and conservative dose conversion factors are derived and tabulated for easy reference in program planning, safety evaluations, and compliance determinations.

  15. Collection and control of tritium bioassay samples at Pantex

    International Nuclear Information System (INIS)

    Pantex is the final assembly/disassembly point for US nuclear weapons. The Pantex internal dosimetry section monitors radiation workers once a month for tritium exposure. In order to manage collection and control of the bioassay specimens efficiently, a bar code system for collection of samples was developed and implemented to speed up the process and decrease the number of errors probable when transferring data. In the past, all the bioassay data from samples were entered manually into a computer database. Transferring the bioassay data from the liquid scintillation counter to each individual's dosimetry record required as much as two weeks of concentrated effort

  16. Bioassays for the determination of nitrification inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Grunditz, Camilla

    1999-07-01

    Requirements for nitrogen reduction in wastewater treatment plants were introduced in Sweden in the early 1990's. This was a governmental move to reduce the nitrogen discharges to the Baltic and Kattegat in order to prevent eutrophication. The nitrification process in wastewater treatment plants is performed by nitrifying bacteria. These are susceptible to inhibition and it is of great importance that the influent water does not contain toxic compounds. Therefore, there is a need for assays for the determination of nitrification inhibition. This thesis describes the development and applications of such bioassays. Pure cultures of Nitrosomonas sp. and Nitrobacter sp. were isolated from activated sludge of a wastewater treatment plant. These cultures were used as test organisms in the development of bioassays for nitrification inhibition measurements. The assays are based on two different principles; cell suspensions of the bacteria, performed in test tubes, and mediated amperometric biosensors with the bacteria immobilised. Ammonia oxidation and nitrite oxidation are studied separately without interference from other organisms, which makes it easier to interpret the results. The cell suspension assays were applied to samples of industrial and municipal wastewater. The Nitrosomonas and Nitrobacter assays showed to have different inhibition patterns. A large percentage of the Swedish municipal wastewater treatment plants were found to receive inhibitory influent water, but the inhibition level was generally low. Compared to an assay based on activated sludge, the screening method, the pure culture assays found more samples of influent water strongly inhibitory or stimulating. The highest correlation was found between the screening method and the Nitrosomonas assay. The Nitrobacter assay was found to be the most sensitive method. Assessment of toxicity of a number of chemical substances was studied using the biosensors, together with the cell suspension assays

  17. Bioassay Phantoms Using Medical Images and Computer Aided Manufacturing

    International Nuclear Information System (INIS)

    A radiation bioassay program relies on a set of standard human phantoms to calibrate and assess radioactivity levels inside a human body for radiation protection and nuclear medicine imaging purposes. However, the methodologies in the development and application of anthropomorphic phantoms, both physical and computational, had mostly remained the same for the past 40 years. We herein propose a 3-year research project to develop medical image-based physical and computational phantoms specifically for radiation bioassay applications involving internally deposited radionuclides. The broad, long-term objective of this research was to set the foundation for a systematic paradigm shift away from the anatomically crude phantoms in existence today to realistic and ultimately individual-specific bioassay methodologies. This long-term objective is expected to impact all areas of radiation bioassay involving nuclear power plants, U.S. DOE laboratories, and nuclear medicine clinics.

  18. Bioassay Phantoms Using Medical Images and Computer Aided Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Dr. X. Geroge Xu

    2011-01-28

    A radiation bioassay program relies on a set of standard human phantoms to calibrate and assess radioactivity levels inside a human body for radiation protection and nuclear medicine imaging purposes. However, the methodologies in the development and application of anthropomorphic phantoms, both physical and computational, had mostly remained the same for the past 40 years. We herein propose a 3-year research project to develop medical image-based physical and computational phantoms specifically for radiation bioassay applications involving internally deposited radionuclides. The broad, long-term objective of this research was to set the foundation for a systematic paradigm shift away from the anatomically crude phantoms in existence today to realistic and ultimately individual-specific bioassay methodologies. This long-term objective is expected to impact all areas of radiation bioassay involving nuclear power plants, U.S. DOE laboratories, and nuclear medicine clinics.

  19. Bioassay-Directed Fractionation of Diesel and Biodiesel Emissions

    Science.gov (United States)

    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...

  20. Bioassay for SF 86-327, a new antifungal agent.

    OpenAIRE

    Kan, V L; Henderson, D. K.; Bennett, J.E.

    1986-01-01

    A bioassay with Trichophyton mentagrophytes is described for SF 86-327, an allylamine antifungal agent. SF 86-327 serum concentrations were measured by bioassay in 117 serum sampler from five patients receiving 500 mg/day. The peak, trough, and area under the concentration-time curve were determined after the first dose and at steady state. Drug accumulation occurred with prolonged therapy.

  1. Plant bioassays to assess toxicity of textile sludge compost

    OpenAIRE

    Araújo Ademir Sérgio Ferreira de; Monteiro Regina Teresa Rosim

    2005-01-01

    Composting of industrial wastes is increasing because of recycling requirements set on organic wastes. The evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. The toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. Compost samples were mixed with water (seed germination bioassay) or nutrient solution (plant growth b...

  2. Acarine attractants: Chemoreception, bioassay, chemistry and control.

    Science.gov (United States)

    Carr, Ann L; Roe, Michael

    2016-07-01

    The Acari are of significant economic importance in crop production and human and animal health. Acaricides are essential for the control of these pests, but at the same time, the number of available pesticides is limited, especially for applications in animal production. The Acari consist of two major groups, the mites that demonstrate a wide variety of life strategies, i.e., herbivory, predation and ectoparasitism, and ticks which have evolved obligatory hematophagy. The major sites of chemoreception in the acarines are the chelicerae, palps and tarsi on the forelegs. A unifying name, the "foretarsal sensory organ" (FSO), is proposed for the first time in this review for the sensory site on the forelegs of all acarines. The FSO has multiple sensory functions including olfaction, gustation, and heat detection. Preliminary transcriptomic data in ticks suggest that chemoreception in the FSO is achieved by a different mechanism from insects. There are a variety of laboratory and field bioassay methods that have been developed for the identification and characterization of attractants but minimal techniques for electrophysiology studies. Over the past three to four decades, significant progress has been made in the chemistry and analysis of function for acarine attractants in mites and ticks. In mites, attractants include aggregation, immature female, female sex and alarm pheromones; in ticks, the attraction-aggregation-attachment, assembly and sex pheromones; in mites and ticks host kairomones and plant allomones; and in mites, fungal allomones. There are still large gaps in our knowledge of chemical communication in the acarines compared to insects, especially relative to acarine pheromones, and more so for mites than ticks. However, the use of lure-and-kill and lure-enhanced biocontrol strategies has been investigated for tick and mite control, respectively, with significant environmental advantages which warrant further study. PMID:27265828

  3. Soil bioassays and the {sup 129}I problem

    Energy Technology Data Exchange (ETDEWEB)

    Sheppard, S.C. [Atomic Energy of Canada Ltd., Pinawa, Manitoba (Canada)

    1995-12-31

    Iodine-129 is a very long-lived radionuclide associated with spent nuclear fuel. Because {sup 129}I has a 10{sup 7}-year half-life, is very mobile in the environment and is a biologically essential element, it is the most limiting radionuclide affecting disposal of spent fuel. Traditionally, the potential impacts of {sup 129}I have been estimated for human receptors, with the implicit assumption that all other organisms are less at risk. Risk is the operative word, the objective for protection of humans is to protect individuals, whereas the objective for other biota is usually to protect populations. Here, {sup 129}I poses an interesting problem: the half-life is so long it is barely radioactive. Thus, the chemical toxicity may be more limiting than the radiological impact. A series of soil bioassays were employed, including a life-cycle plant (Brassica rapa) bioassay, a modified earthworm survival bioassay, a microarthropod colonization/survival bioassay, and a series of more common soil and aquatic bioassays. Chemical toxicity was indicated at soil concentrations as low as 5 mg kg{sup {minus}1}. At these levels, radiological impact on non-human biota would not be expected, and therefore the chemical toxicity effects are more critical. However, human food-chain model estimates show these levels, as pure {sup 129}I, would be unacceptable for human radiological exposure, so that for {sup 129}I, protection of the human environment should also be protective of non-human biota.

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

    Science.gov (United States)

    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. PMID:21800546

  5. Environmental effects of dredging. A chronic sublethal sediment bioassay with the marine polychaete nereis (Neanthes) arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, T.M.; Moore, D.W.; Bridges, T.S.

    1995-01-01

    This note provides a general overview of a new 28-day chronic sublethal sediment bioassay designed for the regulatory evaluation of dredged material. The bioassay uses survival and growth rate endpoints with the polychaete Nereis (Neanthes) arenaceodentata. The primary technical reference for this new bioassay is Dillon, Moore, and Reish (in press), upon which this overview is based. Sediment bioassays are used to assess the aggregate toxicity of sediment associated anthropogenic chemicals. Historically, these bioassays have measured survival of highly sensitive species following acute exposures (10 days). A new generation of sediment bioassays is being developed in which the subtle, sublethal response of test species is measured following chronic sediment exposures (Dillon 1993).

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

    Science.gov (United States)

    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. PMID:17067048

  7. Method comparison for 241Am emergency urine bioassay.

    Science.gov (United States)

    Li, Chunsheng; Sadi, Baki; Benkhedda, Karima; St-Amant, Nadereh; Moodie, Gerry; Ko, Raymond; Dinardo, Anthony; Kramer, Gary

    2010-10-01

    241Am is one of the high-risk radionuclides that might be used in a terrorist attack. 241Am in urine bioassay can identify the contaminated individuals who need immediate medical intervention and decontamination. This paper compares three methods for the measurement of 241Am in urine, namely liquid scintillation counting (LSC), inductively coupled plasma mass spectrometry (ICP-MS) and gamma spectrometry (GS), at two levels, 20 and 2 Bq l(-1). All three methods satisfied the ANSI N13.30 radio-bioassay criteria for accuracy and repeatability. ICP-MS offered the best sensitivity and fastest sample turnaround; however, the ICP-MS system used in this work may not be available in many bioassay laboratories. LSC and GS are more commonly available instruments. GS requires minimal or no sample preparation, which makes it a good candidate method. Moreover, the sample throughput can be significantly improved if the GS and LSC methods are automated. PMID:20573683

  8. An examination of the analysis of radiostrontiums in bioassay applications

    International Nuclear Information System (INIS)

    Radiostrontiums are among the most radiologically significant radionuclides in the nuclear reactor environment due to their relatively high fission yield, long physical half-life, volatility and mobility in the workplace, and long retention times in tissues such as bone. Effective bioassay programs include analytical processes that consider prospective monitoring requirements provided by screening measurements, as well as the retrospective monitoring requirements provided by screening measurements following an intake. Chromatography using crown ethers as well as the use of spectrometry techniques with advanced liquid-scintillation counters or solid-state surface-barrier detectors appear to have significant benefits for Sr bioassay programs. (author). 90 refs., 2 tabs., 3 figs

  9. A statistical treatment of bioassay pour fractions

    Science.gov (United States)

    Barengoltz, Jack; Hughes, David

    A bioassay is a method for estimating the number of bacterial spores on a spacecraft surface for the purpose of demonstrating compliance with planetary protection (PP) requirements (Ref. 1). The details of the process may be seen in the appropriate PP document (e.g., for NASA, Ref. 2). In general, the surface is mechanically sampled with a damp sterile swab or wipe. The completion of the process is colony formation in a growth medium in a plate (Petri dish); the colonies are counted. Consider a set of samples from randomly selected, known areas of one spacecraft surface, for simplicity. One may calculate the mean and standard deviation of the bioburden density, which is the ratio of counts to area sampled. The standard deviation represents an estimate of the variation from place to place of the true bioburden density commingled with the precision of the individual sample counts. The accuracy of individual sample results depends on the equipment used, the collection method, and the culturing method. One aspect that greatly influences the result is the pour fraction, which is the quantity of fluid added to the plates divided by the total fluid used in extracting spores from the sampling equipment. In an analysis of a single sample’s counts due to the pour fraction, one seeks to answer the question: What is the probability that if a certain number of spores are counted with a known pour fraction, that there are an additional number of spores in the part of the rinse not poured. This is given for specific values by the binomial distribution density, where detection (of culturable spores) is success and the probability of success is the pour fraction. A special summation over the binomial distribution, equivalent to adding for all possible values of the true total number of spores, is performed. This distribution when normalized will almost yield the desired quantity. It is the probability that the additional number of spores does not exceed a certain value. Of course

  10. Assessment of acrylamide toxicity using a battery of standardised bioassays.

    Science.gov (United States)

    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. PMID:26751864

  11. Field deployable technique for 90Sr emergency bioassay

    International Nuclear Information System (INIS)

    Rapid bioassay is very important for immediate and near-term consequence management, which includes identifying contaminated individuals and providing necessary medical intervention during a radiological or nuclear emergency. This paper reports the application of a newly developed bioassay technique for 90Sr in urine on a field deployable instrument, the TriathlerR. Performance of this field technique for sensitivity, accuracy and repeatability is evaluated against bioassay criteria (ANSI N13.30). This field technique offers the following analytical merits: (1) minimum detectable activity of 121 Bq l-1 when 20 ml of urine is used; (2) relative bias of 11.1% and relative precision of 3.2% at the level of 45 Bq per 20 ml of urine and (3) sample turnaround time of less than 1 h. The technique meets the requirements for emergency bioassay when a committed effective dose of 0.5 Sv is used as the action dose threshold for medical intervention. Sample throughput can be significantly improved if this technique is automated. (authors)

  12. STRESS ETHYLENE: A BIOASSAY FOR RHIZOSPHERE-APPLIED PHYTOTOXICANTS

    Science.gov (United States)

    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 ...

  13. Artificial diets for life tables bioassays of TPB in Mississippi

    Science.gov (United States)

    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 ...

  14. Microplate Bioassay for Determining Substrate Selectivity of "Candida rugosa" Lipase

    Science.gov (United States)

    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…

  15. Bioassay for aquatic ecosystems review and classification; Rassegna dei principali test di ecotossicologia acquatica

    Energy Technology Data Exchange (ETDEWEB)

    Sanci, Antonella; Rosa, Silvia [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1997-09-01

    Bioassay play a crucial role in assessing the actual or potential impacts of anthropogenic agents on the natural environment. In this technical report, literature on bioassays for aquatic ecosystems has been reviewed and classified. Problems associated with the choice and application of bioassays are discussed.

  16. BioAssay Ontology (BAO: a semantic description of bioassays and high-throughput screening results

    Directory of Open Access Journals (Sweden)

    Smith Robin P

    2011-06-01

    Full Text Available Abstract Background High-throughput screening (HTS is one of the main strategies to identify novel entry points for the development of small molecule chemical probes and drugs and is now commonly accessible to public sector research. Large amounts of data generated in HTS campaigns are submitted to public repositories such as PubChem, which is growing at an exponential rate. The diversity and quantity of available HTS assays and screening results pose enormous challenges to organizing, standardizing, integrating, and analyzing the datasets and thus to maximize the scientific and ultimately the public health impact of the huge investments made to implement public sector HTS capabilities. Novel approaches to organize, standardize and access HTS data are required to address these challenges. Results We developed the first ontology to describe HTS experiments and screening results using expressive description logic. The BioAssay Ontology (BAO serves as a foundation for the standardization of HTS assays and data and as a semantic knowledge model. In this paper we show important examples of formalizing HTS domain knowledge and we point out the advantages of this approach. The ontology is available online at the NCBO bioportal http://bioportal.bioontology.org/ontologies/44531. Conclusions After a large manual curation effort, we loaded BAO-mapped data triples into a RDF database store and used a reasoner in several case studies to demonstrate the benefits of formalized domain knowledge representation in BAO. The examples illustrate semantic querying capabilities where BAO enables the retrieval of inferred search results that are relevant to a given query, but are not explicitly defined. BAO thus opens new functionality for annotating, querying, and analyzing HTS datasets and the potential for discovering new knowledge by means of inference.

  17. The use of cultivars of Raphanus sativus for cytokinin bioassay

    Directory of Open Access Journals (Sweden)

    Dorota Kubowicz

    2013-12-01

    Full Text Available Six cultivars of radish (Raphanus sativus were tested for their usefulness in radish cytokinin bioassay by the method of Letham (1971. The best cultivar was found to be 'Sopel Lodu' which responds well to both zeatin and 2iP over a wide range of concentrations. The fresh weight of cotyledons increased at most by 71.5% (if treated with zeatin or 101.0% (if treated with 2iP compared to untreated cotyledons. This cultivar is also sensitive to the partially purified cytokinin-like fraction isolated from the pine (Pinus silvestris cambial region. The cultivar 'Sopel Lodu' is therefore proposed to be a suitable plant for cytokinin bioassays.

  18. An emergency bioassay method for 210Po in urine

    International Nuclear Information System (INIS)

    A rapid method was developed to efficiently measure 210Po in urine samples in an emergency situation. Polonium-210 in small urine samples (10 mL) was spontaneously deposited on a stainless steel disc in 1 M HCl at room temperature for 4 h in a polyethylene bottle. The metallic disc was then counted for 4 h by alpha spectrometry. The developed method allowed the preparation of large sample batch in a short time. The method meets the requirements for an emergency bioassay procedure. - Highlights: • A new method was developed to rapidly measurement 210Po in urine. • The method is easy to perform and does not require highly qualified staffs. • Large sample batches can be simultaneously prepared. • The method meets the requirements for an emergency bioassay method

  19. Development of software for internal dose calculation from bioassay measurements

    International Nuclear Information System (INIS)

    Recently developed biokinetic models of ICRP permit increasingly realistic descriptions of the behaviour of radionuclides in the human body. This, however, has made the interpretation of bioassay data extremely difficult. Thus computer programs for implementing these models are in need, but very few are available. The present work describes personal-computer-based software, MONDAL2 (monitoring to dose calculation ver. 2), that enables users to estimate intake activity and the resulting effective doses from bioassay measurements for both workers and members of the public. This software runs on Microsoft Windows 95, 98, Millennium edition, 2000 or XP. If the system is to be fully copied to a hard disk, hard disk space of 23 MB is required. This software is distributed by the National Inst. of Radiological Sciences free of charge. (authors)

  20. The Text-mining based PubChem Bioassay neighboring analysis

    Directory of Open Access Journals (Sweden)

    Wang Yanli

    2010-11-01

    Full Text Available Abstract Background In recent years, the number of High Throughput Screening (HTS assays deposited in PubChem has grown quickly. As a result, the volume of both the structured information (i.e. molecular structure, bioactivities and the unstructured information (such as descriptions of bioassay experiments, has been increasing exponentially. As a result, it has become even more demanding and challenging to efficiently assemble the bioactivity data by mining the huge amount of information to identify and interpret the relationships among the diversified bioassay experiments. In this work, we propose a text-mining based approach for bioassay neighboring analysis from the unstructured text descriptions contained in the PubChem BioAssay database. Results The neighboring analysis is achieved by evaluating the cosine scores of each bioassay pair and fraction of overlaps among the human-curated neighbors. Our results from the cosine score distribution analysis and assay neighbor clustering analysis on all PubChem bioassays suggest that strong correlations among the bioassays can be identified from their conceptual relevance. A comparison with other existing assay neighboring methods suggests that the text-mining based bioassay neighboring approach provides meaningful linkages among the PubChem bioassays, and complements the existing methods by identifying additional relationships among the bioassay entries. Conclusions The text-mining based bioassay neighboring analysis is efficient for correlating bioassays and studying different aspects of a biological process, which are otherwise difficult to achieve by existing neighboring procedures due to the lack of specific annotations and structured information. It is suggested that the text-mining based bioassay neighboring analysis can be used as a standalone or as a complementary tool for the PubChem bioassay neighboring process to enable efficient integration of assay results and generate hypotheses for

  1. Soil bioassays as tools for sludge compost quality assessment

    OpenAIRE

    Domene, X.; Solà i Sau, Laura; Ramírez Hernández, Wilson Ariel; Alcañiz, Josep M.; Andrés Pastor, Pilar

    2011-01-01

    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...

  2. New experimental tools for bioassays with whitefly in laboratory

    Directory of Open Access Journals (Sweden)

    Thiago Luis Martins Fanela

    2012-12-01

    Full Text Available The objective of this work was to develop an experimental kit for assessments of repellency, deterrence for oviposition, and insecticidal activity on adults of the whitefly Bemisia tabaci biotype B. The kit, which consisted of arenas and nebulizer, was effective for conducting bioassays, and the application of aqueous extracts by inhaler was adequate. The techniques are simple, cheap, and may contribute to research on this insect.

  3. A Bioassay System Using Bioelectric Signals from Small Fish

    Science.gov (United States)

    Terawaki, Mitsuru; Soh, Zu; Hirano, Akira; Tsuji, Toshio

    Although the quality of tap water is generally examined using chemical assay, this method cannot be used for examination in real time. Against such a background, the technique of fish bioassay has attracted attention as an approach that enables constant monitoring of aquatic contamination. The respiratory rhythms of fish are considered an efficient indicator for the ongoing assessment of water quality, since they are sensitive to chemicals and can be indirectly measured from bioelectric signals generated by breathing. In order to judge aquatic contamination accurately, it is necessary to measure bioelectric signals from fish swimming freely as well as to stably discriminate measured signals, which vary between individuals. However, no bioassay system meeting the above requirements has yet been established. This paper proposes a bioassay system using bioelectric signals generated from small fish in free-swimming conditions. The system records signals using multiple electrodes to cover the extensive measurement range required in a free-swimming environment, and automatically discriminates changes in water quality from signal frequency components. This discrimination is achieved through an ensemble classification method using probability neural networks to solve the problem of differences between individual fish. The paper also reports on the results of related validation experiments, which showed that the proposed system was able to stably discriminate between water conditions before and after bleach exposure.

  4. Toxicity of copper-spiked sediments to Tubifex tubifex (Oligochaeta, Tubificidae): Comparison of the 28-day reproductive bioassay with an early-life-stage bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Vecchi, M.; Pasteris, A.; Bonomi, G. (Univ. degli Studi di Bologna (Italy). Dipt. di Biologia Evoluzionistica Sperimentale); Reynoldson, T.B. (Environment Canada, Burlington, Ontario (Canada). National Water Research Inst.)

    1999-06-01

    Two sediment bioassay methods using Tubifex tubifex (Mueller, 1774) as the test species were compared. The first was an adult reproduction test, the second an early-life-stage survival test. The duration of both bioassays is 28 d and the amount of work required was similar; they may be useful alternatives to each other in different circumstances (e.g., the early life stage bioassay could be carried out with smaller volumes of sediment). The two bioassays were performed simultaneously on copper-spiked sediments. Sediments from two freshwater and two terrestrial sites were used; five separate, nonsimultaneous experiments were performed, one for each sediment or soil and a further experiment with soil with a good supplement. In the adult bioassay, there were large differences in the production of cocoons, eggs, and young among the control treatments of the five experiments. There were also major differences in the NOEC and LOEC for copper between the tested substrates. The early life stage bioassay appears to be less sensitive to copper toxicity than the adult reproductive bioassay since NOECs and LOECs are higher for early survival than for the most sensitive endpoints of the adult bioassay in three experiments out of five.

  5. In Vitro Biologic Activities of the Antimicrobials Triclocarban, Its Analogs, and Triclosan in Bioassay Screens: Receptor-Based Bioassay Screens

    OpenAIRE

    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 ac...

  6. Applications of the Poly-K Statistical Test to Life-Time Cancer Bioassay Studies

    OpenAIRE

    Gebregziabher, Mulugeta; Hoel, David

    2009-01-01

    The statistical analysis of cancer bioassay data has historically depended on the pathological determination of the experimental animal's cause of death. The poly-k statistical test has provided a method of statistical analysis of animal bioassay data without the need for cause of death information. The test has been shown to have good statistical properties in the typical 2-year cancer bioassay. However, while the poly-k test has been applied to chronic lifetime animal studies, it has not be...

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

    OpenAIRE

    Jun Zhang; Jui-Hua Hsieh; Hao Zhu

    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...

  8. Comparison of five bioassay techniques for assessing sediment-bound contaminants

    OpenAIRE

    Ahlf, Wolfgang; Calmano, Wolfgang; Erhard, Judith; Förstner, Ulrich

    1989-01-01

    Biological response could not be predicted based on chemical concentration of the sediment contaminants. Bioassays integrate the response of test organisms to contaminants and nutrients. Comparative results of five acute bioassays indicated that Neubauer phytoassay was the most sensitive. The mircobial biomass and algal growth tests indicated a response to the availability of contaminants and nutrients. These results suggest the usefulness of a diversity of bioassays in toxicity testing of se...

  9. Fluorescent bioassays for toxic metals in milk and yoghurt

    Directory of Open Access Journals (Sweden)

    Siddiki Mohammad Shohel

    2012-10-01

    Full Text Available Abstract Background From a human health viewpoint, contaminated milk and its products could be a source of long-term exposure to toxic metals. Simple, inexpensive, and on-site assays would enable constant monitoring of their contents. Bioassays that can measure toxic metals in milk or yoghurt might reduce the risk. For this purpose, the green fluorescent protein (GFP-tagged trans factors, ArsR-GFP and CadC-GFP, together with their cis elements were used to develop such bioassays. Results ArsR-GFP or CadC-GFP, which binds either toxic metal or DNA fragment including cis element, was directly mixed with cow’s milk or yoghurt within a neutral pH range. The fluorescence of GFP, which is reflected by the association/dissociation ratio between cis element and trans factor, significantly changed with increasing externally added As (III or Cd (II whereas smaller responses to externally added Pb (II and Zn (II were found. Preparation and dilution of whey fraction at low pH were essential to intrinsic zinc quantification using CadC-GFP. Using the extraction procedure and bioassay, intrinsic Zn (II concentrations ranging from 1.4 to 4.8 mg/l for milk brands and from 1.2 to 2.9 mg/kg for yoghurt brands were determined, which correlated to those determined using inductively coupled plasma atomic emission spectroscopy. Conclusions GFP-tagged bacterial trans factors and cis elements can work in the neutralized whole composition and diluted whey fraction of milk and yoghurt. The feature of regulatory elements is advantageous for establishment of simple and rapid assays of toxic metals in dairy products.

  10. Efficient algal bioassay based on short-term photosynthetic response

    International Nuclear Information System (INIS)

    A procedure is described for measuring the effects of toxicants on algal photosynthesis (carbon-14 bicarbonate (H14CO3)uptake) in 4-h experiments. The results for individual aromatic compounds and the water-soluble fraction (WSF) of a synthetic oil are presented as examples of applications of the bioassay. The toxicity of the WSF varied among the seven algal species tested, and the responses of some species were pH-dependent. With Selenastrum capricornutum as the test organism, the bioassay results were unaffected by variations in pH from 7.0 to 9.0, light intensity from 40 to 200 μeinsteins m-2 s-1, culture density up to 0.5 mg chlorophyll a per litre, and agitation up to 100 rpm. The photosynthesis bioassay is simpler and faster (4 h versus 4 to 14 days), uses smaller culture volumes, and requires less space than static culture-growth tests. One person can conveniently test four materials per day, and the entire procedure, including preparation, exposure, and analysis, takes less than two days. The short incubation time reduces bottle effects such as pH changes, accumulation of metabolic products, nutrient depletion, and bacterial growth. Processes that remove or alter the test materials are also minimized. The data presented here indicate that algal photosynthesis is inhibited at toxicant concentrations similar to those that cause acute effects in aquatic animals. A model of a pelagic ecosystem is used to demonstrate that even temporary (seven-day) inhibition of algal photosynthesis can have a measurable impact on other trophic levels, particularly if the other trophic levels are also experiencing toxic effects. 25 references, 6 figures, 1 table

  11. Bioassays for the toxicity of petroleum oils to birds

    International Nuclear Information System (INIS)

    A study was conducted to develop bioassays to predict the potential toxicity of petroleum oils to birds. Two bioassay systems were assessed. The first was the embryonated chicken egg. Mortality and pathological changes were examined in embryos treated with 1-30 μl of petroleum oils applied to the eggshell on day 9 of incubation and examined on day 13. Lesions seen consistently were extensive edema, superficial zones of hepatic necrosis, distension of the heart, and enlargement of the spleen. These morphological changes could not be reproduced by covering the eggshell with inert sealants. Liver necrosis and edema were found in embryos exposed to the 6 petroleum oils, suggesting a common mechanism of toxic action. The 96-h LD25 and ED25 (lethal and effective doses, respectively, affecting 25% of the population) for liver necrosis were determined for 6 petroleum oils. Estimates of the ED25 for liver necrosis could discriminate among the toxicities of the 6 oils better than could estimates of the LD25, and the ED25 was more reliable and consistent when bioassays were repeated on the same oil. The second system was the red blood cell exposed to petroleum oils in vitro, designed to model the Heinz body hemolytic anemia described in birds ingesting crude oil. Formation of methemoglobin and Heinz bodies was measured in rabbit erythrocytes exposed to naphthalene or extracts of petroleum oils after incubation. The assay could detect dose-responsive Heinz body formation in red cells treated with naphthalene, but Heinz body formation was not detected in red cells treated with 6 different petroleum oils. 326 refs., 19 figs., 46 tabs

  12. Application of the proposed new ICRP lung model to bioassay

    International Nuclear Information System (INIS)

    The new lung model being proposed by ICRP for use in radiation protection dosimetry requires the calculation of doses to separate regions of the respiratory tract, multiplying these doses by factors proportional to the risk per unit dose to each region, and summing over all regions of the lung to give a ''weighted'' lung dose. This paper compares the doses that would be calculated form bioassay measurements using the new model with those calculated using the current model, which essentially uses total lung burden to estimate lung dose

  13. The use of cultivars of Raphanus sativus for cytokinin bioassay

    OpenAIRE

    Dorota Kubowicz; Ewa Grodzka

    2013-01-01

    Six cultivars of radish (Raphanus sativus) were tested for their usefulness in radish cytokinin bioassay by the method of Letham (1971). The best cultivar was found to be 'Sopel Lodu' which responds well to both zeatin and 2iP over a wide range of concentrations. The fresh weight of cotyledons increased at most by 71.5% (if treated with zeatin) or 101.0% (if treated with 2iP) compared to untreated cotyledons. This cultivar is also sensitive to the partially purified cytokinin-like fraction is...

  14. Herbicide impact on Hormosira banksii gametes measured by fluorescence and germination bioassays

    International Nuclear Information System (INIS)

    The innovative bioassay described here involves chlorophyll a fluorescence measurements of gametes from the macroalgae, Hormosira banksii, where gametes (eggs) were exposed to Diuron, Irgarol and Bromacil. Response was assessed as percent inhibition from control of effective quantum yield (ΔF/Fm') of photosystem II, herein referred to as % PSII Inhibition. This was measured with the dual-channelled pulse amplitude modulated (PAM) fluorometer, ToxY-PAM. The fluorescence bioassay was run simultaneously with an established H. banksii germination bioassay to compare sensitivity, precision, and time-to-result. The fluorescence bioassay gave highly sensitive results evidenced by EC5s (% PSII Inhibition) for Diuron, Irgarol and Bromacil being three, four and three orders of magnitude (respectively) lower than EC5s generated from the germination bioassays. Precision of the fluorescence bioassay was demonstrated with low coefficient of variations (<30%) for all three toxicants. With regard to time, the fluorescence bioassay gave results within 6 h, as opposed to more than 50 h for the germination bioassay. - Chlorophyll a fluorescence measurements form the basis of a macroalgal bioassay with many advantages over germination-based methods

  15. Vicia faba bioassay for environmental toxicity monitoring: A review.

    Science.gov (United States)

    Iqbal, Munawar

    2016-02-01

    Higher plants are recognized as excellent genetic models to detect cytogenetic and mutagenic agents and are frequently used in environmental monitoring studies. Vicia faba (V. faba) bioassay have been used to study DNA damages i.e., chromosomal and nuclear aberrations induced by metallic compounds, pesticides, complex mixtures, petroleum derivates, toxins, nanoparticles and industrial effluents. The main advantages of using V. faba is its availability round the year, economical to use, easy to grow and handle; its use does not require sterile conditions, rate of cell division is fast, chromosomes are easy to score, less expensive and more sensitive as compared to other short-term tests that require pre-preparations. The V. faba test offers evaluation of different endpoints and tested agents can be classified as cytotoxic/genotoxic/mutagenic. This test also provides understanding about mechanism of action, whether the tested agent is clastogenic or aneugenic in nature. In view of advantages offered by V. faba test system, it is used extensively to assess toxic agents and has been emerged as an important bioassay for ecotoxicological studies. Based on the applications of V. faba test to assess the environmental quality, this article offers an overview of this test system and its efficiency in assessing the cytogenetic and mutagenic agents in different classes of the environmental concerns. PMID:26414739

  16. LIFE CYCLE BIOASSAY FOR ASSESSMENT OF THE EFFECTS OF TOXIC CHEMICALS USING RAPID CYCLING OF BRASSICA

    Science.gov (United States)

    Initial evaluation of a new plant life cycle bioassay for the assessment of the effects of toxic chemicals is presented. he bioassay features a rapid cycling Brassica species that can complete its life cycle in as little as 36 days. he herbicide dalapon (2,2 dichloropropionic aci...

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

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    Full Text Available 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.

  18. Toxicity assessment using different bioassays and microbial biosensors.

    Science.gov (United States)

    Hassan, Sedky H A; Van Ginkel, Steven W; Hussein, Mohamed A M; Abskharon, Romany; Oh, Sang-Eun

    2016-01-01

    Toxicity assessment of water streams, wastewater, and contaminated sediments, is a very important part of environmental pollution monitoring. Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on ecotoxicity assessment. Recently, different biological assays for toxicity assessment based on higher and lower organisms such as fish, invertebrates, plants and algal cells, and microbial bioassays have been used. This review focuses on microbial biosensors as an analytical device for environmental, food, and biomedical applications. Different techniques which are commonly used in microbial biosensing include amperometry, potentiometry, conductometry, voltammetry, microbial fuel cells, fluorescence, bioluminescence, and colorimetry. Examples of the use of different microbial biosensors in assessing a variety of environments are summarized. PMID:27071051

  19. Neotropical electric fishes (Gymnotiformes) as model organisms for bioassays

    Institute of Scientific and Technical Information of China (English)

    Milena Ferreira; Isac Silva de Jesus; Eliana Feldberg; JoséAntônioAlves-Gomes

    2015-01-01

    Electric fishes (Gymnotiformes) inhabit Central and South America and form a relatively large group with more than 200 species. Besides a taxonomic challenge due to their still unresolved systematic, wide distribution and the variety of habitats they occupy, these fishes have been intensively studied due to their peculiar use of bioelectricity for electrolocation and communication. Conventional analysis of cells, tissues and organs have been complemented with the studies on the electric organ discharges of these fishes. This review compiles the results of 13 bioassays developed during the last 50 years, which used the quickness, low costs and functionality of the bioelectric data collection of Gymnotiformes to evaluate the effects of environmental contaminants and neuroactive drugs.

  20. Bioassay techniques for 55Fe in urine samples

    International Nuclear Information System (INIS)

    Solvent extraction, ion chromatography and several rapid screening methods were developed and evaluated for 55Fe bioassay applications. Isopropyl ether and TNOA column extractions had radiochemical recoveries exceeding 90%. These were very reproducible with a coefficient of variation less than 5%. Screening techniques investigated included direct counting of ashed urine solids, and Fe(OH)3. precipitated from urine. The sensitivities (2-50 Bq/d urine) of the screening methods were usually limited by the effective urine volume that could be counted in a liquid scintillation counter. The reference isopropyl ether and chromatography methods could easily achieve sensitivities well below the 1 Bq/d urine output target. (author). 49 refs., 3 tabs., 5 figs

  1. Seroprevalensi Toxoplasma gondii pada Kambing dan Bioassay Patogenitasnya pada Kucing

    Directory of Open Access Journals (Sweden)

    Ni Made Yunik Novita Dewi Dewi

    2013-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE The study aimed to determine seroprevalence of Toxoplasmosis in goats sloughtered at Kampung Jawa, Denpasar, Bali and to evaluate their pathogenicities through bioassay in cats.One hundred serums and meats of goats were collected. Anti-Toxoplasma gondii antibody was determined using Indirect Haemaglutination (IHA test. The pathogenicity bioassay of Toxoplasma gondii was carried out through inoculating the meats of goats which had seropositive of Toxoplasma gondii to the cats. The pathogenicity was evaluated using the intensity of oocyte sheding from the cats. The result showed that the seroprevalence of Toxoplasmosis was 46%. There was not significant difference between pathogenicity of Toxoplasma gondii in cat inoculated with meat of goat which had a high and low titer of antibody against Toxoplasma gondii. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; text-align:justify; line-height:150%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

  2. Comprehensive integration of homogeneous bioassays via centrifugo-pneumatic cascading.

    Science.gov (United States)

    Godino, Neus; Gorkin, Robert; Linares, Ana V; Burger, Robert; Ducrée, Jens

    2013-02-21

    This work for the first time presents the full integration and automation concept for a range of bioassays leveraged by cascading a centrifugo-pneumatic valving scheme to sequentially move several liquids through shared channel segments for multi-step sample preparation into the detection zone. This novel centrifugo-pneumatic liquid handling significantly simplifies system manufacture by obviating the need for complex surface functionalization procedures or hybrid material integration, as it is common in conventional valving methods such as capillary burst valves or sacrificial valves. Based on the centrifugo-pneumatic valving scheme, this work presents a toolkit of operational elements implementing liquid loading/transfer, metering, mixing and sedimentation in a microstructured polymer disc. As a proof of concept for the broad class of homogeneous bioassays, the full integration and automation of a colorimetric nitrate/nitrite test for the detection of clinically relevant nitric oxide (NO) in whole blood is implemented. First, 40 μL of plasma is extracted from a 100 μL sample of human blood, incubated for one hour with the enzymatic mixture (60 μL), and finally reacted with 100 μL of colorimetric (Greiss) reagents. Following just a single loading phase at the beginning of the process, all of these steps are automated through the centrifugo-pneumatic cascade with a high level of flow control and synchronization. Our system shows good correlation with controls up to 50 μM of nitrate, which adequately covers the healthy human range (4 to 45.3 μM). PMID:23250328

  3. Comparison of solid and liquid-phase bioassays using ecoscores to assess contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Lors, Christine [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, LGCgE-MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France); Centre National de Recherche sur les Sites et Sols Pollues, 930 Boulevard Lahure, BP 537, 59505 Douai Cedex (France); Ponge, Jean-Francois, E-mail: ponge@mnhn.fr [Museum National d' Histoire Naturelle, Departement Ecologie et Gestion de la Biodiversite, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Martinez Aldaya, Maite [Museum National d' Histoire Naturelle, Departement Ecologie et Gestion de la Biodiversite, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Damidot, Denis [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, LGCgE-MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France)

    2011-10-15

    Bioassays on aqueous and solid phases of contaminated soils were compared, belonging to a wide array of trophic and response levels and using ecoscores for evaluating ecotoxicological and genotoxicological endpoints. The method was applied to four coke factory soils contaminated mainly with PAHs, but also to a lesser extent by heavy metals and cyanides. Aquatic bioassays do not differ from terrestrial bioassays when scaling soils according to toxicity but they are complementary from the viewpoint of ecological relevance. Both aquatic and terrestrial endpoints are strongly correlated with concentrations of 3-ring PAHs. This evaluation procedure allows us to propose a cost-effective battery which embraces a wide array of test organisms and response levels: it includes two rapid bioassays (Microtox) and springtail avoidance), a micronucleus test and three bioassays of a longer duration (algal growth, lettuce germination and springtail reproduction). This battery can be recommended for a cost-effective assessment of polluted/remediated soils. - Highlights: > Comparison of liquid- and solid-phase bioassays on contaminated soils, using ecoscores. > Complementarity of liquid- and solid-phase bioassays for the evaluation of environmental hazards. > Proposal for a restricted battery of 5 most sensitive tests. > Use of this restricted battery for a cost-effective assessment of polluted/remediated soils. - Aqueous and solid phases of contaminated soils give similar results in terms of toxicity but are complementary for the evaluation of environmental hazards by ecoscores.

  4. Review of literature on bioassay methods for estimating radionuclides in urine

    International Nuclear Information System (INIS)

    Bioassay methods of certain important radionuclides encountered in the nuclear fuel cycle operations, viz., thorium, uranium, sup(239)Pu, sup(241)Am, sup(90)Sr, sup(99)Tc, sup(106)Ru, sup(137)Cs are reviewed, with special emphasis on urinalysis. Since the preconcentration is an important prerequisite for bioassay, various preconcentration methods are also discussed. Brief account of various instruments both nuclear and analytical used in the bioassay programme is included. The sensitivities of the methods cited in the literature vis-a-vis the derived recording levels indicated in ICRP recommendations are compared. Literature surveyed up to 1990 is tabulated. (author). 96 refs., 1 fig ., 3 tabs

  5. Evaluation on the Joint Action Between Chlorsulfuron and Haloxyfop-R by Bioassay

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The joint action between chlorsulfuron and haloxyfop-R was evaluated by bioassay with wheat and com.respectivly. The dose-response curve derived from wheat bioassay showed that the inhibition of haloxyfop-Rto wheat root growth wasn't affected by the increasing rate of chlorsulfuron. It indicated that chlorsulfuron had no antagonism to haloxyfop-R. Meanwhile ,the variation analysis of corn bioassay indicated that these two herbicides had joint action on inhibition to corn primary root growth. The joint action was evaluated as addis tive action by using Isobole Method. So chlorsulfuron and haloxyfop-R could be used as tank mixture.

  6. Luminescent Lanthanide Reporters for High-Sensitivity Novel Bioassays.

    Energy Technology Data Exchange (ETDEWEB)

    Anstey, Mitchell; Fruetel, Julia A.; Foster, Michael E.; Hayden, Carl C.; Buckley, Heather L.; Arnold, John

    2013-09-01

    Biological imaging and assay technologies rely on fluorescent organic dyes as reporters for a number of interesting targets and processes. However, limitations of organic dyes such as small Stokes shifts, spectral overlap of emission signals with native biological fluorescence background, and photobleaching have all inhibited the development of highly sensitive assays. To overcome the limitations of organic dyes for bioassays, we propose to develop lanthanide-based luminescent dyes and demonstrate them for molecular reporting applications. This relatively new family of dyes was selected for their attractive spectral and chemical properties. Luminescence is imparted by the lanthanide atom and allows for relatively simple chemical structures that can be tailored to the application. The photophysical properties offer unique features such as narrow and non-overlapping emission bands, long luminescent lifetimes, and long wavelength emission, which enable significant sensitivity improvements over organic dyes through spectral and temporal gating of the luminescent signal.Growth in this field has been hindered due to the necessary advanced synthetic chemistry techniques and access to experts in biological assay development. Our strategy for the development of a new lanthanide-based fluorescent reporter system is based on chelation of the lanthanide metal center using absorbing chromophores. Our first strategy involves %22Click%22 chemistry to develop 3-fold symmetric chelators and the other involves use of a new class of tetrapyrrole ligands called corroles. This two-pronged approach is geared towards the optimization of chromophores to enhance light output.

  7. Bioassay-based risk assessment of complex mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, K.C.; Huebner, H.J. [Texas A and M Univ., College Station, TX (United States). Dept. of Veterinary Anatomy and Public Health

    1996-12-31

    The baseline risk assessment often plays an integral role in various decision-making processes at Superfund sites. The present study reports on risk characterizations prepared for seven complex mixtures using biological and chemical analysis. Three of the samples (A, B, and C) were complex mixtures of polycyclic aromatic hydrocarbons (PAHs) extracted from coal tar; while four samples extracted from munitions-contaminated soil contained primarily nitroaromatic hydrocarbons. The chemical-based risk assessment ranked sample C as least toxic, while the risk associated with samples A and B was approximately equal. The microbial bioassay was in general agreement for the coal tar samples. The weighted activity of the coal tar extracts in Salmonella was 4,960 for sample C, and 162,000 and 206,000 for samples A and B, respectively. The bacterial mutagenicity of 2,4,6-trinitrotoluene contaminated soils exhibited an indirect correlation with chemical-based risk assessment. The aqueous extract of sample 004 induced 1,292 net revertants in Salmonella, while the estimated risk to ingestion and dermal adsorption was 2E-9. The data indicate that the chemical-based risk assessment accurately predicted the genotoxicity of the PAHs, while the accuracy of the risk assessment for munitions contaminated soils was limited due to the presence of metabolites of TNT degradation. The biological tests used in this research provide a valuable compliment to chemical analysis for characterizing the genotoxic risk of complex mixtures.

  8. Colorimetric paper bioassay for the detection of phenolic compounds.

    Science.gov (United States)

    Alkasir, Ramiz S J; Ornatska, Maryna; Andreescu, Silvana

    2012-11-20

    A new type of paper based bioassay for the colorimetric detection of phenolic compounds including phenol, bisphenol A, catechol and cresols is reported. The sensor is based on a layer-by-layer (LbL) assembly approach formed by alternatively depositing layers of chitosan and alginate polyelectrolytes onto filter paper and physically entrapping the tyrosinase enzyme in between these layers. The sensor response is quantified as a color change resulting from the specific binding of the enzymatically generated quinone to the multilayers of immobilized chitosan on the paper. The color change can be quantified with the naked eye but a digitalized picture can also be used to provide more sensitive comparison to a calibrated color scheme. The sensor was optimized with respect to the number of layers, pH, enzyme, chitosan and alginate amounts. The colorimetric response was concentration dependent, with a detection limit of 0.86 (±0.1) μg/L for each of the phenolic compounds tested. The response time required for the sensor to reach steady-state color varied between 6 and 17 min depending on the phenolic substrate. The sensor showed excellent storage stability at room temperature for several months (92% residual activity after 260 days storage) and demonstrated good functionality in real environmental samples. A procedure to mass-produce the bioactive sensors by inkjet printing the LbL layers of polyelectrolyte and enzyme on paper is demonstrated. PMID:23113670

  9. Long-wavelength-emitting nanocrystals for bioassay applications

    Science.gov (United States)

    Leppert, Valerie J.; Harvey, Ashley S.; McCool, Geoff D.; Quinlan, Forest T.; Feng, Jun; Shan, Guomin; Stroeve, Pieter; Risbud, Subhash H.; Hammock, Bruce D.; Kennedy, Ian M.

    2002-11-01

    New fluorophores that can be excited using visible or near-infrared radiation are of considerable interest for application in environmental and complex bioassays, where background fluorescence is exacerbated by ultra-violet or blue excitation. Useful labels for biomolecules include infrared emitting semiconductor nanoparticles that can be blue-shifted into the near-infrared and visible through quantum confinement effects, oxides of iron, and rare earth oxides. In this work, the synthesis of 6 nm average diameter lead selenide nanocrystals (well below the Bohr exciton diameter of 92 nm) through a reverse micelle technique; and the synthesis of iron and europium oxides with particles less than 5 nm in diameter by pulsed laser ablation is reported. The europium oxide nanoparticles' emission showed a large Stokes shift (144 nm or 216 nm, depending on excitation wavelength); a narrow, symmetric emission line at 610 nm (FWHM of 8 nm); and long lifetime (300 μs). The Eu2O3 nanoparticles, which were coated with silica for functionalization, displayed a greatly enhanced sensitivity over a conventional ELISA (0.025 ng ml-1 vs. 0.1 ng ml-1) when run in an atrazine immunoassay.

  10. Analyzing bioassay data using Bayesian methods-A primer

    International Nuclear Information System (INIS)

    The classical statistics approach used in health physics for the interpretation of measurements is deficient in that it does not allow for the consideration of needle in a haystack effects, where events that are rare in a population are being detected. In fact, this is often the case in health physics measurements, and the false positive fraction is often very large using the prescriptions of classical statistics. Bayesian statistics provides an objective methodology to ensure acceptably small false positive fractions. The authors present the basic methodology and a heuristic discussion. Examples are given using numerically generated and real bioassay data (Tritium). Various analytical models are used to fit the prior probability distribution, in order to test the sensitivity to choice of model. Parametric studies show that the normalized Bayesian decision level kα-Lc/σ0, where σ0 is the measurement uncertainty for zero true amount, is usually in the range from 3 to 5 depending on the true positive rate. Four times σ0 rather than approximately two times σ0, as in classical statistics, would often seem a better choice for the decision level

  11. Phototoxicity activity of Psoralea drupacea L. using Atremia salina bioassay system

    Directory of Open Access Journals (Sweden)

    Mohammad Ramezani

    2011-07-01

    Conclusion: The result showed that P. drupacea methanolic extract and chloroform fraction have phototoxicity in A. salina bioassay system and their toxic effect is related to phototoxic constituents such as psoralen.

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

    Science.gov (United States)

    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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Ferrao-Filho, Aloysio da S., E-mail: aloysio@ioc.fiocruz.b [Laboratorio de Avaliacao e Promocao da Saude Ambiental, Departamento de Biologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21045-900 (Brazil); Soares, Maria Carolina S., E-mail: mcarolsoares@gmail.co [Departamento de Engenharia Sanitaria e Ambiental Faculdade de Engenharia, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-900 (Brazil); Freitas de Magalhaes, Valeria, E-mail: valeria@biof.ufrj.b [Laboratorio de Ecofisiologia e Toxicologia de Cianobacterias, Instituto de Biofisica Carlos Chagas Filho, CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ 21949-900 (Brazil); Azevedo, Sandra M.F.O., E-mail: sazevedo@biof.ufrj.b [Laboratorio de Ecofisiologia e Toxicologia de Cianobacterias, Instituto de Biofisica Carlos Chagas Filho, CCS, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ 21949-900 (Brazil)

    2010-06-15

    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 (ET{sub 50}) was adopted as the endpoint. Paralysis of swimming movements was observed between approx0.5-3 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 ET{sub 50}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. - A new Daphnia bioassay, as an alternative to the mouse bioassay, is able to detect effects of fast-acting, potent neurotoxins in raw water.

  14. Using animal dosimetry models to interpret human bioassay data for actinide exposures

    International Nuclear Information System (INIS)

    Bioassay and dosimetry models are needed to estimate intakes of radionuclides, and to calculate radiation doses to target tissues following such intakes. Because of the diversity of exposure materials, individual biological variabilities, and the general lack of adequate bioassay information and knowledge of the metabolism of radionuclides, current models are based mostly on empiricism. This paper describes biokinetic/dosimetry models for U, Am and Cm. They are based on experimental data developed from studies in dogs that inhaled one of the above radionuclides in specific chemical forms and specific particle sizes. The models, which are based on similar biological principles, and, therefore, have similar structure, are applied to the very sparse human bioassay data available from cases of exposure to either U, Am, or Cm. The results thus far indicate that the lung retention for the different actinides are well described by the models, that urinary bioassay data can be described within limited time periods, and that the fecal excretion rate is not adequately described. Improvements in modeling are predicted on increased publication of human bioassay data, and better cooperative interaction between model developers and health protection professionals responsible for industrial bioassay programs. (author) 36 refs.; 6 figs.; 2 tabs

  15. Conceptual design for comprehensive automation in radiochemical analysis of bioassay samples

    International Nuclear Information System (INIS)

    Bioassay Laboratory of Health Physics Division is entrusted with the task of carrying out the bioassay monitoring of occupational workers from various plants/divisions of BARC for various radionuclides like Pu, U, Th, 90Sr, 3H etc. On the average about 1400-1500 analyses are performed on 700-800 urine samples collected annually from radiation workers. The workload has increased by 1.5 to 2.0 times in recent past and is expected to increase further due to expanding nuclear programmes of the Department. Therefore, it was planned to carry out automation in various stages of bioassay sample handling, processing and analysis under the XI plan programme. Automation work in Bioassay Lab. is planned to be taken-up in three stages namely, automation in initial processing of i) urine samples, ii) fecal samples and iii) automation in radiochemical analysis of bioassay samples. In the initial phase, automation in radiochemical analysis of bioassay samples has been taken up

  16. Recent Radiochemical Procedures for Bio-Assay Studies at Trombay

    International Nuclear Information System (INIS)

    The bio-assay laboratory at Trombay carries out nearly 2000 analyses of urine samples annually for different radionuclides. The most abundant isotopes of interest are Th232, Th228, Ra226, Ra224 and Ra228, U natural, fission products and Pu239. The others are Co60, I131, P32, Cs137, H3, Sr90, etc. Analyses of a large number of samples containing low levels of activity with speed calls for development of special techniques when high specificity with good yields are desired. Urine presents a very complex matrix with a large amount of complexing organic material as well as variable salt content. Wet ashing procedures are time-consuming and cumbersome where samples of about 1 to 1.5 l are required to be destroyed. The paper presents some very recent methods developed in the laboratory and details of tracer studies involved in the development of these methods. Ra228: Measurement of mesothorium in urine is made after separation of Ac228 grown in equilibrium with it. Radium present in urine is co-precipitated with BaSO4 and Ac228 allowed to grow. The precipitate is dissolved in perchloric acid after the addition of Pb, Bi and La carriers. The insoluble sulphates are precipitated with diluted H2SO4. Ac2'28 in the supernate is carried on LaF3 and counted for beta activity and checked for decay. Ra228 is calculated from observed Ac228 activity after correcting for decay and chemical recovery. Thorium: The method describes techniques developed for the co-precipitation of thorium with calcium oxalate without wet ashing urine. A study of exact experimental conditions for quantitative precipitation of thorium is reported. The paper also gives tracer experiments carried out for study of interference from phosphates and calcium in the final extraction of thorium with TTA. Thorium-232 is estimated spectrophotometrically and thorium-228 in the separated thorium fraction by separation of Ra224 after equilibration. . Among other studies reported are the determinations of Cs137, P32, Co

  17. Bioassay of thermal protection afforded by candidate flight suit fabrics.

    Science.gov (United States)

    Knox, F S; Wachtel, T L; McCahan, G R

    1979-10-01

    The United States Army Aeromedical Research Laboratory (USAARL) porcine cutaneous bioassay technique was used to determine what mitigating effect four thermally protective flight suit fabrics would have on fire-induced skin damage. The fabrics were 4.8-ox twill weave Nomex aramide, 4.5-oz stabilized twill weave polybenzimidazole, 4.8-oz plain weave experimental high-temperature polymer (HT4), and 4.8-oz plain weave Nomex aramide (New Weave Nomex or NWN). Each fabric sample was assayed 20 times in each of four configurations: as a single layer in contact with the skin; as a single layer with a 6.35 mm (0.25 in) air gap between fabric and skin; in conjuction with a cotton T-shirt with no air gaps; and, finally, in conjuction with a T-shirt with a 6.35 mm air gap between T-shirt and fabric. Bare skin was used as a control. A JP-4 fueled furnace was used as a thermal source and was adjested to deliver a mean heat flux of 3.07 cal/cm2/s. The duration of exposure was 5 s. Four hundred burn sites were graded using clinical observation and microscopic techniques. Used as single layers, none of the fabrics demonstrated superiority in providing clinically significant protection. When used with a cotton T-shirt, protection was improved. Protection improved progressively for all fabrics and configuration when an air gap was introduced. The experimental high-temperature polymer consistently demonstrated lower heat flux transmission in all configurations, but did not significantly reduce clinical burns. PMID:518445

  18. Plasmonically amplified bioassay - Total internal reflection fluorescence vs. epifluorescence geometry.

    Science.gov (United States)

    Hageneder, Simone; Bauch, Martin; Dostalek, Jakub

    2016-08-15

    This paper investigates plasmonic amplification in two commonly used optical configurations for fluorescence readout of bioassays - epifluorescence (EPF) and total internal reflection fluorescence (TIRF). The plasmonic amplification in the EPF configuration was implemented by using crossed gold diffraction grating and Kretschmann geometry of attenuated total reflection method (ATR) was employed in the TIRF configuration. Identical assay, surface architecture for analyte capture, and optics for the excitation, collection and detection of emitted fluorescence light intensity were used in both TIRF and EPF configurations. Simulations predict that the crossed gold diffraction grating (EPF) can amplify the fluorescence signal by a factor of 10(2) by the combination of surface plasmon-enhanced excitation and directional surface plasmon-coupled emission in the red part of spectrum. This factor is about order of magnitude higher than that predicted for the Kretschmann geometry (TIRF) which only took advantage of the surface plasmon-enhanced excitation. When applied for the readout of sandwich interleukin 6 (IL-6) immunoassay, the plasmonically amplified EPF geometry designed for Alexa Fluor 647 labels offered 4-times higher fluorescence signal intensity compared to TIRF. Interestingly, both geometries allowed reaching the same detection limit of 0.4pM despite of the difference in the fluorescence signal enhancement. This is attributed to inherently lower background of fluorescence signal for TIRF geometry compared to that for EPF which compensates for the weaker fluorescence signal enhancement. The analysis of the inflammation biomarker IL-6 in serum at medically relevant concentrations and the utilization of plasmonic amplification for the fluorescence measurement of kinetics of surface affinity reactions are demonstrated for both EPF and TIRF readout. PMID:27260457

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

    International Nuclear Information System (INIS)

    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. - The avoidance test using the soil springtail Folsomia candida is globally more sensitive to PAH contamination than acute and chronic toxicity bioassays using plants and animals but a battery of tests could reveal better in detail.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lors, Christine [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France); Centre National de Recherche sur les Sites et Sols Pollues, 930 Boulevard Lahure, BP 537, 59505 Douai Cedex (France); Ponge, Jean-Francois, E-mail: ponge@mnhn.f [Museum National d' Histoire Naturelle, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Martinez Aldaya, Maite [Museum National d' Histoire Naturelle, CNRS UMR 7179, 4 Avenue du Petit-Chateau, 91800 Brunoy (France); Damidot, Denis [Universite Lille Nord de France, 1bis rue Georges Lefevre, 59044 Lille Cedex (France); Ecole des Mines de Douai, MPE-GCE, 941 rue Charles-Bourseul, 59500 Douai (France)

    2010-08-15

    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. - The avoidance test using the soil springtail Folsomia candida is globally more sensitive to PAH contamination than acute and chronic toxicity bioassays using plants and animals but a battery of tests could reveal better in detail.

  1. Selecting a sensitive battery of bioassays to detect toxic effects of metals in effluents.

    Science.gov (United States)

    de Paiva Magalhães, Danielly; da Costa Marques, Mônica Regina; Fernandes Baptista, Darcilio; Forsin Buss, Daniel

    2014-09-01

    The use of bioassay batteries is necessary to evaluate toxic effects at various biological levels. The selection of bioassays without prior testing and determination of the most sensitive/suitable groups for each impact may allow the discharge of effluents that pose a threat to the environment. The present study tested and selected a battery of sensitive ecotoxicological bioassays for detecting toxic effects of metals. The sensitivities of six organisms were evaluated (algae Pseudokirchneriella subcapitata and Chlorella vulgaris, Cladocera Daphnia similis and Ceriodaphnia dubia, and fish Poecilia reticulata and Danio rerio) after exposure to 10 individual metal species deemed toxic to the aquatic environment (Ag(+), Cd(2+), Cu(+), Cu(2+), Cr(3+), Cr(6+), Pb(2+), Ni(2+), Zn(2+), and Hg(2+)) and to real (steel-mill) and laboratory simulated effluents. In the bioassays, fish were the least sensitive; D. rerio showed no sensitivity to any of the effluents tested. P. subcapitata was a good bioindicator of Cr(3+) toxicity, and D. similis was the most sensitive organism to Hg(2+); but the toxic effect of effluents with higher levels of Hg(2+) was better detected by C. dubia. The most sensitive battery of bioassays to detect low concentrations of dissolved metals in effluents was the 72-h chronic test with C. vulgaris and the 48-h acute test with C. dubia. PMID:25199585

  2. Characterization of chemical waste site contamination and its extent using bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, J.M.; Callahan, C.A.; Cline, J.F.; Greene, J.C.; McShane, M.C.; Miller, W.E.; Peterson, S.A.; Simpson, J.C.; Skalski, J.R.

    1984-12-01

    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 Mountain 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.

  3. Development and validation of microbial bioassay for quantification of Levofloxacin in pharmaceutical preparations

    Institute of Scientific and Technical Information of China (English)

    Nishant A. Dafale; Uttam P. Semwal; Piyush K. Agarwal; Pradeep Sharma; G.N. Singh

    2015-01-01

    The aim of this study was to develop and validate a simple, sensitive, precise and cost-effective one-level agar diffusion (5þ1) bioassay for estimation of potency and bioactivity of Levofloxacin in pharmaceutical preparation which has not yet been reported in any pharmacopoeia. Among 16 microbial strains, Bacillus pumilus ATCC-14884 was selected as the most significant strain against Levofloxacin. Bioassay was optimized by investigating several factors such as buffer pH, inoculums concentration and reference standard concentration. Identification of Levofloxacin in commercial sample Levoflox tablet was done by FTIR spectroscopy. Mean potency recovery value for Levofloxacin in Levoflox tablet was estimated as 100.90%. A validated bioassay method showed linearity (r2 ¼ 0.988), precision (Interday RSD ¼ 1.05%, between analyst RSD ¼ 1.02%) and accuracy (101.23%, RSD ¼ 0.72%). Bioassay was correlated with HPLC using same sample and estimated potencies were 100.90%and 99.37%, respectively. Results show that bioassay is a suitable method for estimation of potency and bioactivity of Levofloxacin pharmaceutical preparations.

  4. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays.

    Science.gov (United States)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine; Witt, Gesine; Haase, Nora; Escher, Beate I

    2016-06-01

    Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the environment into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total extraction or polymer-based passive sampling combined with either solvent spiking or passive dosing. PMID:26804122

  5. Strategies for Transferring Mixtures of Organic Contaminants from Aquatic Environments into Bioassays

    DEFF Research Database (Denmark)

    Jahnke, Annika; Mayer, Philipp; Schäfer, Sabine;

    2016-01-01

    Mixtures of organic contaminants are ubiquitous in the environment. Depending on their persistence and physicochemical properties, individual chemicals that make up the mixture partition and distribute within the environment and might then jointly elicit toxicological effects. For the assessment...... and monitoring of such mixtures, a variety of cell-based in vitro and low-complexity in vivo bioassays based on algae, daphnids or fish embryos are available. A very important and sometimes unrecognized challenge is how to combine sampling, extraction and dosing to transfer the mixtures from the...... environment into bioassays, while conserving (or re-establishing) their chemical composition at adjustable levels for concentration-effect assessment. This article outlines various strategies for quantifiable transfer from environmental samples including water, sediment, and biota into bioassays using total...

  6. Characterization of chemical-waste-site contamination and determination of its extent using bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, J.M.; Skalski, J.R.; Cline, J.F.; McShane, M.C.; Miller, W.E.

    1986-01-01

    The purpose of using bioassays to evaluate soils, soil elutriates, and surface and subsurface water from hazardous chemical waste sites is to provide a more-direct, integrated estimate of environmental toxicity. Based on bioassay data, chemical waste sites can be ranked according to their toxic potential or mapped for cleanup operations. The objectives of the study were to (a) assess the comparative sensitivity of test organisms to known chemicals, (b) determine if the chemical components in field soil and water samples of unknown composition could be inferred from laboratory studies using pure chemicals and (c) investigate kriging (a relatively new statistical mapping technique) of bioassay results as a method to define the areal extent of contamination. In support of these objectives, data are presented on the response of the organisms listed in the Hazardous Materials Assessment Team (HMAT) test protocol (3) to pure chemicals from three chemical subgroups (heavy metals, insecticides, and herbicides).

  7. Toxicity Assessment of Sediments with Natural Anomalous Concentrations in Heavy Metals by the Use of Bioassay

    Directory of Open Access Journals (Sweden)

    Francisco Martín

    2010-01-01

    Full Text Available The potential toxicity in riverbed sediments was assessed with a bioassay using the bioluminescent bacteria Vibrio fischeri. The selected area was characterized by the presence of ultramafic rocks (peridotites, and the sediments had high values in Ni, Cr, and Co. For the toxicity bioassay with Vibrio fischeri, water-soluble forms were used. The results indicated that most of the samples had a very low degree of toxicity, with 10% of reduction in luminescence in relation to the control; meanwhile 25% of the samples had a moderate degree of toxicity with a reduction in luminescence between 13 and 21% in relation to the control. The toxicity index correlated significantly with the concentrations of Ni and Cr in the water extracts. This toxicity bioassay was proved to be a sensitive and useful tool to detect potential toxicity in solutions, even with anomalous concentrations in heavy metals of natural origin.

  8. Current status of bioassay procedures to detect and quantify previous exposures to radioactive materials

    International Nuclear Information System (INIS)

    This paper was prepared by a working group established by the Oak Ridge Associated Universities (ORAU) for the purpose of assessing the current capabilities of bioassay methods that can be used to determine the occurrence and magnitude of a previous internal deposition of one or more radionuclides. The first five sections discuss general features of the use of in-vitro bioassay samples to achieve this purpose. The remainder of the paper is focused on the possible use of urine bioassay procedures to detect and quantify internal depositions of radionuclides that may have occurred in United States occupation troops in Hiroshima or Nagasaki, Japan, prior to 1 July 1946, or to personnel who participated in atmospheric nuclear weapons tests conducted between 1945 and 1962. Theoretical calculations were made to estimate the quantities of various radionuclides produced in a 20-kiloton (kt) nuclear detonation that might still be present in measurable quantities in people today if they were exposed 25 to 40 y ago

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

    Science.gov (United States)

    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

  10. Implementation of bioassay methods to improve assessment of incorporated radionuclides

    International Nuclear Information System (INIS)

    Full text: Internal exposure to uranium and thorium can principally be assessed from external radiation measurements, exhalation measurements, or the assay of these elements excreted in urine or feces. Since both 232Th and 238U emit only photon radiations of low energy and with low emission probabilities, their detection limits by in vivo counting are of the order of kBq even when sophisticated devices are used. Consequently, usually bioassay methods are used for the incorporation monitoring of workers. Alpha spectrometry is the commonly applied technique, usually employed to measure 232Th and 238U in urine or fecel samples. For accurate analysis of body contents, 24 hours collections of urine or feces are usually used. The fecal activity, however, resembles predominantly the intake by ingestion of these nuclides during the last few days whereas the urinary excretion is more closely related to the body content of the nuclides. However, urinary excretion is also varying with the actual intake of 232Th and/or 238U. The measurement of these nuclides in urine by alpha-spectrometry requires tedious and time-consuming chemical work-up to prepare the samples for spectrometric analysis. Therefore, the number of analyses, which can be carried out is quite low and the results are available only after a time lag of several days. Additionally, under certain conditions the alpha-spectrometry is not sensitive enough. Other methods that have been developed may be confined to the availability of certain devices being difficult to access (e.g. nuclear reactors for radiochemical neutron activation analysis). Much better suitable as routine method is the application of inductively coupled plasma mass spectrometry (ICP-MS) for measurements of 232Th and 238U concentrations in urine. For elemental analyses, ICP-MS can already be considered as commonly used method. The present work which was carried out in the framework of an EU project (IDEA: Internal Dosimetry - Enhancements in

  11. Review of Bioassays for Monitoring Fate and Transport ofEstrogenic Endocrine Disrupting Compounds in Water

    Energy Technology Data Exchange (ETDEWEB)

    CGCampbell@lbl.gov

    2004-01-30

    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.

  12. Development of a cystatin C-specific bioassay for integration into an implantable biochip system

    OpenAIRE

    Damm, Tatjana

    2016-01-01

    The interest in diagnostic biochips is growing. However, most biochips are designed for ex vivo applications. Beyond, an elevated serum human cystatin C (hCC) concentration correlates with various diseases. Thus, hCC was suggested as biomarker. To meet the requirements of an implantable biochip system it is essential to develop an hCC-specific bioassay enabling repetitive measurements.Within this PhD thesis an hCC-specific bioassay was developed which is based on the concentration-dependant r...

  13. Development and application of bioassays for a site-specific risk assessment of contaminated soil

    OpenAIRE

    Rila, J.-P.

    2008-01-01

    Soil risk assessment based on generic approaches is accompanied by a large number of uncertainties. In site-specific risk assessment aimed at identifying the actual effects on the ecosystem by using e.g. bioassays in soil elutriates and taking into account land-use these uncertainties can be largely reduced. In this thesis the application and development of bioassays for a site-specific risk assessment of contaminated soil has been discussed. The first part of this thesis deals with the influ...

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

    International Nuclear Information System (INIS)

    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

  15. A Brine Shrimp Bioassay for Measuring Toxicity and Remediation of Chemicals

    Science.gov (United States)

    Lieberman, Marya

    1999-12-01

    A bioassay using Artemia franciscana (brine shrimp) was adapted to measure the toxicity of household chemicals. One project is described in which students collect dose-response curves for seven commercial flea-killing products. Next, groups of students researched the insecticidal ingredients of the flea products. On the basis of the structures of the active ingredients, they chose remediation methods to make the flea product less toxic to brine shrimp; procedures included copper-catalyzed hydrolysis, adsorption onto activated charcoal, bleach treatment, and photodegradation. No special equipment or supplies are necessary for the bioassay other than the brine shrimp eggs, which can be obtained at any aquarium store.

  16. Beoordeling van gereinigde grond. V. Toepassing van bioassays met planten en regenwormen op verontreinigde en gereinigde gronden

    NARCIS (Netherlands)

    van Gestel CAM; Dirven-van Breemen EM; Kamerman JW

    1992-01-01

    Within the framework of the project "Evaluation of decontaminated soil", the applicability of bioassays with earthworms and plants for the quality assessment of decontaminated soil is investigated. In the final phase of this project, bioassays with earthworms and plants (radish, lettuce)

  17. New in vitro reporter gene bioassays for screening of hormonal active compounds in the environment

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Kateřina; Cajthaml, Tomáš

    2010-01-01

    Roč. 88, č. 4 (2010), s. 839-847. ISSN 0175-7598 R&D Projects: GA ČR GAP503/10/0408 Institutional research plan: CEZ:AV0Z50200510 Keywords : endocrine disruptors * in vitro bioassays * reporter gene assays Subject RIV: EE - Microbiology, Virology Impact factor: 3.280, year: 2010

  18. A RAPID, QUANTITATIVE BIOASSAY FOR DETECTING PHYTOTOXIC GASES USING STRESS-ETHYLENE

    Science.gov (United States)

    A simple bioassay for detecting phytotoxic air pollutants has been developed. Wheat (Triticum aestivum L.) seedlings growing on agar medium in test-tubes are exposed to pollutants for 2 h. Stress-ethylene produced by the seedlings during exposure to the pollutants is collected in...

  19. DEVELOPMENT OF A TEST-TUBE STRESS-ETHYLENE BIOASSAY FOR DETECTING PHYTOTOXIC GASES

    Science.gov (United States)

    A rapid, quantitative bioassay for detecting phytotoxic air pollutants has been developed. The technique uses wheat Triticum aestivum L. or tomato Lycopersicon esculentum L., seedlings growing on an agar medium in test-tubes. The seedlings are exposed to a pollutant in the test-t...

  20. Statistical method for determining and comparing limits of detection of bioassays.

    Science.gov (United States)

    Holstein, Carly A; Griffin, Maryclare; Hong, Jing; Sampson, Paul D

    2015-10-01

    The current bioassay development literature lacks the use of statistically robust methods for calculating the limit of detection of a given assay. Instead, researchers often employ simple methods that provide a rough estimate of the limit of detection, often without a measure of the confidence in the estimate. This scarcity of robust methods is likely due to a realistic preference for simple and accessible methods and to a lack of such methods that have reduced the concepts of limit of detection theory to practice for the specific application of bioassays. Here, we have developed a method for determining limits of detection for bioassays that is statistically robust and reduced to practice in a clear and accessible manner geared at researchers, not statisticians. This method utilizes a four-parameter logistic curve fit to translate signal intensity to analyte concentration, which is a curve that is commonly employed in quantitative bioassays. This method generates a 95% confidence interval of the limit of detection estimate to provide a measure of uncertainty and a means by which to compare the analytical sensitivities of different assays statistically. We have demonstrated this method using real data from the development of a paper-based influenza assay in our laboratory to illustrate the steps and features of the method. Using this method, assay developers can calculate statistically valid limits of detection and compare these values for different assays to determine when a change to the assay design results in a statistically significant improvement in analytical sensitivity. PMID:26376354

  1. The Intersection of CMOS Microsystems and Upconversion Nanoparticles for Luminescence Bioimaging and Bioassays

    Directory of Open Access Journals (Sweden)

    Liping Wei

    2014-09-01

    Full Text Available 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.

  2. Using a Macroalgal δ15N Bioassay to Detect Cruise Ship Waste Water Effluent Inputs

    Science.gov (United States)

    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...

  3. Age and sex related responsiveness of Tribolium castaneum (Coleoptera: Tenebrionidae) in novel behavioral bioassays

    Science.gov (United States)

    The hardiness and mobile nature of Tribolium castaneum (Herbst) make them easy to work with but are the same factors that make their responses to behavior modifying chemical stimuli difficult to evaluate. To overcome these difficulties we developed two bioassays: a two choice test with airflow and a...

  4. A comparative study on bioassay and radioimmunoassay of vasopressin in human urine

    International Nuclear Information System (INIS)

    The excretion of vasopressin in urine from healthy human subjects under different stages of hydration was estimated in urine extracts by bioassay (rat antidiuresis) and radioimmunoassay. In normally hydrated subjects the excretion was 490 plus minus 164 μU/h and 430 plus minus 133μU/h for bioassay and radioimmunoassay respectively (mean plus minus SEM, n=5). After total fluid restriction for 10 to 12 h the excretion increased to 1370 plus minus 329 μU/h for bioassay and 1163 plus minus 279 μU/h for radioimmunoassay (mean plus minus SEM, n=6). An oral water load (25 ml/kg) reduced the value to 169 μU/h (bioassay) and 118 μU/h (radioimmunoassay) (mean, n=2). In general the biological estimations were 20 % higher than the immunological estimations (P<0.01). The urinary vasopressin excretion was positively correlated to urine osmolality. Synthetic arginine vasopressin (AVP) and urine extracts were both heterogeneous in ion exchange chromatography. The immunoreactive material was always eluted in 2 peaks, situated at the same places in the elution diagram. The material in the second peak was biologically active. The first peak from the AVP standard was biologically inactive, whereas the same peak from urine extract was active. This peak was shown to be an artefact formed during the extraction procedure. (author)

  5. Determining UV Inactivation of Toxoplasma gondii Oocysts by Using Cell Culture and a Mouse Bioassay

    Science.gov (United States)

    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...

  6. Bioassay based screening of steroid derivatives in animal feed and supplements

    NARCIS (Netherlands)

    Rijk, J.C.W.; Ashwin, H.M.; Kuijk, van S.J.A.; Groot, M.J.; Heskamp, H.H.; Bovee, T.F.H.; Nielen, M.W.F.

    2011-01-01

    Receptor binding transcription activation bioassays are valuable tools for the screening of steroid hormones in animal feed and supplements. However, steroid derivatives often lack affinity for their cognate receptor and do not show any direct hormonal activity by themselves. These compounds are thu

  7. A fluorescence-based bioassay for antibacterials and its application in screening natural product extracts

    NARCIS (Netherlands)

    Michels, Katharina; Heinke, Ramona; Schöne, Pia; Kuipers, Oscar P; Arnold, Norbert; Wessjohann, Ludger A

    2015-01-01

    The reliable assessment of the biological activity of a minor component embedded in a complex matrix of several hundred compounds is a difficult but common task in the search for natural product-based antibiotics, for example, by bioassay-guided fractionation. To quantify the antibiotic properties,

  8. Evaluation of soil bioassays for use at Washington state hazardous waste sites: A pilot study

    International Nuclear Information System (INIS)

    The Washington State Department of Ecology (Ecology) is developing guidelines to assess soil toxicity at hazardous waste sites being investigated under the Washington Model Toxics Control Act Cleanup Regulation. To evaluate soil toxicity, Ecology selected five bioassay protocols -- Daphnia, Earthworm, Seedling, Fathead Minnow, and Frog Embryo Teratogenesis Assay Xenopus (FETAX) -- for use as screening level assessment tools at six State hazardous waste sites. Sites contained a variety of contaminants including metals, creosote, pesticides, and petroleum products (leaking underground storage tanks). Three locations, representing high, medium, and low levels of contamination, were samples at each site. In general, the high contaminant samples resulted in the highest toxic response in all bioassays. The order of site toxicity, as assessed by overall toxic response, is creosote, petroleum products, metals, and pesticides. Results indicate that human health standards, especially for metals, may not adequately protect some of the species tested. The FETAX bioassay had the greatest overall number of toxic responses and lowest variance. The seedling and Daphnia bioassays had lower and similar overall toxic response results, followed by the earthworm and fathead minnow. Variability was markedly highest for the seedling. The Daphnia and fathead minnow variability were similar to the FETAX level, while the earthworm variability was slightly higher

  9. Determination of Biochemical Oxygen Demand of Area Waters: A Bioassay Procedure for Environmental Monitoring

    Science.gov (United States)

    Riehl, Matthew

    2012-01-01

    A graphical method for determining the 5-day biochemical oxygen demand (BOD5) for a body of water is described. In this bioassay, students collect a sample of water from a designated site, transport it to the laboratory, and evaluate the amount of oxygen consumed by naturally occurring bacteria during a 5-day incubation period. An accuracy check,…

  10. A SIMPLE, RAPID BIOASSAY FOR DETECTING EFFECTS OF POLLUTANTS ON BACTERIA

    Science.gov (United States)

    Since approximately 90% of hazardous wastes reach soil and water for permanent disposal, it is logical that microflora (bacteria) contained in these environments be used to establish initial toxicity levels. Bacteria can be suitable bioassay tools because they are inexpensive to ...

  11. Applicability of the CALUX bioassay for screening of dioxin levels in human milk samples

    DEFF Research Database (Denmark)

    Laier, P.; Cederberg, Tommy Licht; Larsen, John Christian;

    2003-01-01

    The CALUX (chemically activated luciferase expression) bioassay based on rat hepatoma (H4IIE) cells is a sensitive assay for the detection of Ah receptor agonists like 2,3,7,8-substituted chlorinated dibenzo-p-dioxins and dibenzofurans and related PCBs. In this paper, the assay was optimized and...

  12. Complete Genome Sequence of Cyanobium sp. NIES-981, a Marine Strain Potentially Useful for Ecotoxicological Bioassays

    Science.gov (United States)

    Shimura, Yohei; Suzuki, Shigekatsu; Yamagishi, Takahiro; Tatarazako, Norihisa; Kawachi, Masanobu

    2016-01-01

    Cyanobium sp. NIES-981 is a marine cyanobacterium isolated from tidal flat sands in Okinawa, Japan. Here, we report the complete 3.0-Mbp genome sequence of NIES-981, which is composed of a single chromosome, and its annotation. This sequence information may provide a basis for developing an ecotoxicological bioassay using this strain. PMID:27469961

  13. Kinetic microplate bioassays for relative potency of antibiotics improved by partial Least Square (PLS) regression.

    Science.gov (United States)

    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. PMID:26971814

  14. An Estuarine Fish Bioassay for Sensitive Biomonitoring of Oil-related Contamination

    Science.gov (United States)

    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 ...

  15. Comparison of two bioassay methods for determining deltamethrin resistance in German cockroaches (Blattodea: Blattellidae).

    Science.gov (United States)

    Choo, L E; Tang, C S; Pang, F Y; Ho, S H

    2000-06-01

    Susceptibility to deltamethrin of 10 strains of the German cockroach, Blattella germanica (L.), trapped in hotel kitchens in Singapore was determined. Two resistance detection bioassay methods (topical application and World Health Organization glass jar method) were compared. Resistance ratios based on 50% knockdown, obtained by comparison with the S strain, ranged from 17.7 to 4,235 for topical application and from 2.2 to 22 for the glass jar method. A field strain, with consistently low resistance ratios (topical method = 17.7, glass jar method = 2.2), was identified as a potential field strain to be used as a baseline for comparison with other field strains. Resistance ratios for the other field strains obtained by comparison with the R5 strain ranged from 24.5 to 239 for topical application and from 1.2 to 9.8 for the glass jar method. The results of our study demonstrate that deltamethrin-resistant German cockroaches are numerous in Singapore. Comparison between the two bioassay methods showed that there was significant correlation between KD50 and KT50 values. The glass jar method is similar to field situations but topical application is sensitive enough to define the magnitude of resistance. Differences between the two detection bioassays and the factors governing the choice of bioassay in monitoring resistance in German cockroaches are discussed. PMID:10902348

  16. Development of bioassay techniques with extracts from semi-permeable membrane devices (SPMDs)

    Energy Technology Data Exchange (ETDEWEB)

    Metcalfe, T.L.; White, P.; Mackay, D.; Metcalfe, C. [Trent Univ., Peterborough, Ontario (Canada). Environmental and Resource Studies Program

    1995-12-31

    Semi-permeable membrane devices (SPMDs), consisting of polyethylene bags filled with triolein, have been used to monitor for lipophilic organic contaminants in water. Although extracts from SPMDs have most often been analyzed for concentrations of organic contaminants, there is also the potential to monitor the toxicity of these extracts using in vitro and in vivo bioassays. SPMDs were deployed for four weeks at several sites along a corridor extending from Peche Island in the Detroit River to Pelee Island in western Lake Erie to monitor the distribution of toxic organic contaminants in the water. Analysis of the extracts from the SPMDs for concentrations of PCBs and other organochlorine compounds, and polynuclear aromatic hydrocarbons (PAHs) indicated that the regions in the Detroit River within the Trenton Channel and near Zug Island were the most highly contaminated. Bioassays conducted with extracts from the SPMDs included the in vitro SOS Chromotest for genotoxic activity, an acute lethality test with Daphnia magna, and a fish embryotoxicity test with embryos of Japanese medaka (Oryzias latipes). These bioassay data generally indicated that the toxicity and concentrations of organic contaminants in the SPMD extracts were correlated. This study indicates that there is potential to use short-term bioassays of extracts from SPMDs to monitor for in situ contamination in the aquatic environment.

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

    Science.gov (United States)

    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

    2016-03-01

    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

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

    Science.gov (United States)

    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...

  19. Bioassays for the detection of chemicals that can form bioactivation-dependent reactive free radicals

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, J.T.; Commandeur, J.N.M.; Wezel, A. van; Vermeulen, N.P.E. (Free Univ. of Amsterdam (Netherlands). Div. of Molecular Toxicology National Inst. for Coastal and Marine Management, Den Haag (Netherlands))

    1999-06-01

    In vitro bioassays were developed for the detection of chemicals that can be bioactivated to reactive free radical species in microsomal fractions. Two methods were deployed, a down-scaled spectrophotometric method for the detection of chemicals that can cause lipid peroxidation using the measurement of thiobarbituric acid-reactive substances (TBARS) and a fluorometric method for the detection of chemicals that can undergo redox cycling to generate superoxide radicals based on the detection of hydrogen peroxide. The response of these systems to prototypical and environmentally relevant chemicals, including tetrachloromethane and paraquat, was examined. The detection limit of the lipid peroxidation bioassay, based on the formation of TBARS, was about 1 [micro]M for tetrachloromethane; that of the bioassay for redox cyclers, based on the production of hydrogen peroxide, was about 2 [micro]M for paraquat and about 100-fold lower for the potent redox cycler 2,3,5,6-tetramethylbenzoquinone (TMBQ). Several binary mixtures of chemicals were tested for potential nonadditive effects in both in vitro systems. Some antagonistic effects among halogenated methanes were observed in the lipid peroxidation assay. In the hydrogen peroxide production assay, greater than additive effects were seen between small concentrations of paraquat and TMBQ. A number of surface water concentrates from several locations in The Netherlands, with various levels of chemical contamination, exhibited a weak response in the hydrogen peroxide production assay. Acetone was found to interfere with the response of the bioassay to redox cyclers and, therefore, the water concentrates (originally in acetone) were transferred to ethanol prior to testing. A good correlation was observed between the response of the water concentrates in the hydrogen peroxide production assay and their acute toxicity in Daphnia magna. No correlation was observed between this bioassay response and toxicity in the Microtox

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

    Science.gov (United States)

    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. PMID:21842660

  1. Compost maturity assessment using physicochemical, solid-state spectroscopy, and plant bioassay analysis.

    Science.gov (United States)

    Kumar, D Senthil; Kumar, P Satheesh; Rajendran, N M; Anbuganapathi, G

    2013-11-27

    The vermicompost produced from flower waste inoculated with biofertilizers was subjected to compost maturity test: (i) physicochemical method (pH, OC, TN, C:N); (ii) solid state spectroscopic analysis (FTIR and (13)C CPMAS NMR); and (iii) plant bioassay (germination index). The pH of vermicompost was decreased toward neutral, C:N ratio vermicomposts result shows reduction of complex organic materials into simple minerals which indicates the maturity of the experimental vermicompost product than the control. The increased aliphatic portion incorporated with flower residues may be due to the synthesis of alkyl, O-alkyl, and COO groups by the microbes present in the gut of earthworm. Plant bioassays are considered the most conventional assessment of compost maturity analysis, and subsequently, it shows the effect of vermicompost maturity on the germination index of Vigna mungo . PMID:24191667

  2. Regional differences in stratum corneum reactivity to surfactants. Quantitative assessment using the corneosurfametry bioassay.

    Science.gov (United States)

    Henry, F; Goffin, V; Maibach, H I; Piérard, G E

    1997-12-01

    The skin does not react similarly to the presence of xenobiotics over all anatomic sites. Distinct regional differences have been described for irritancy and percutaneous absorption. The present study assesses the regional variation of stratum corneum reactivity to surfactants using the corneosurfametry bioassay. Stratum corneum was harvested from 6 body sites in 20 young adults. Corneosurfametry was performed using water, 1% SLS and a 5% soap solution. Data show that the best variable to assess regional variability in irritancy is the overall difference in corneosurfametry (ODC), comparing the effect of a given surfactant with water. The dorsal hand and volar forearm were the least reactive, the neck, forehead, back and dorsal foot the most reactive, sites. It is concluded that the corneosurfametry bioassay, through the ODC variable, is a practically noninvasive tool for the evaluation of regional variation in irritancy at the level of the stratum corneum. PMID:9455629

  3. Trace analysis of ecdysones by gas--liquid chromatography, radioimmunoassay, and bioassay

    International Nuclear Information System (INIS)

    A radioimmunoassay was compared to a gas-liquid chromatographic assay and a bioassay as a method for quantifying ecdysone titers in arthropods. In addition a continuous-development thin layer chromatographic technique was evaluated as a means for separating various ecdysone analogues. The carboxymethoxyamine derivative of β-ecdysone was synthesized and characterized by several spectral methods. This derivative was conjugated to bovine serum albumin to afford a suitable antigen and injected into rabbits. The antisera produced shows a moderate affinity for β-ecdysone and cross-reacts with many ecdysone analogues. Ecdysones were also quantified directly as trimethylsilyl ethers using a 63Ni electron capture detector in a gas-liquid chromatographic system. Less than 50 pg of material could be detected per injection. Both of these techniques and the Musca domestica bioassay were used for the comparative analysis of a number of biological samples. The advantages and disadvantages of the various methods are discussed. (U.S.)

  4. Development and bioassay of transgenic Chinese cabbage expressing potato proteinase inhibitor II gene

    OpenAIRE

    Zhang, Junjie; Liu, Fan; Yao, Lei; Luo, Chen; Yin, Yue; Wang, Guixiang; Huang, Yubi

    2012-01-01

    Lepidopteran larvae are the most injurious pests of Chinese cabbage production. We attempted the development of transgenic Chinese cabbage expressing the potato proteinase inhibitor II gene (pinII) and bioassayed the pest-repelling ability of these transgenic plants. Cotyledons with petioles from aseptic seedlings were used as explants for Agrobacterium-mediated in vitro transformation. Agrobacterium tumefaciens C58 contained the binary vector pBBBasta-pinII-bar comprising pinII and bar genes...

  5. Bioassay-Directed Isolation of Active Compounds with Antiyeast Activity from a Cassia fistula Seed Extract

    OpenAIRE

    Subramanion L. Jothy; Sreenivasan Sasidharan; Lai Ngit Shin; Lachimanan Yoga Latha; Yee Ling Lau; Yeng Chen; Zuraini Zakaria

    2011-01-01

    Background and objective: Cassia fistula L belongs to the family Leguminosae, and it is one of the most popular herbal products in tropical countries. C. fistula seeds have been used as a herbal medicine and have pharmacological activity which includes anti-bacterial, anti-fungal, and antioxidant properties. The goal of this study was to identify compounds from C. fistula seeds which are responsible for anti-Candida albicans activity using bioassay-directed isolation. Results: The preliminary...

  6. Bioassay- and liquid chromatography/mass spectrometry-guided acetylcholinesterase inhibitors from Picriafel-terrae

    Directory of Open Access Journals (Sweden)

    Lu Wen

    2013-01-01

    Full Text Available Background: Picria fel-terrae is a traditional Chinese medicine. Materials and Methods: A new approach to the search for acetylcholinesterase (AChE inhibitors from Picria fel-terrae is presented. Results: Bioassay- and LC-MS-guided fractionation of the ethyl acetate extract was from traditional Chinese medicine P.fel-terrae. Following primary extraction, the ethyl acetate extracts fraction of P.fel-terrae showed strong AChE inhibitory activities. So the sample was separated using highperformance liquid chromatography (HPLC. The effluent was split towards two identical 96-well fraction collectors, and the presence of the biologically interesting portion and chromatographic fractions could be readily detected by analyzing selected ion chromatograms through an electrophoresis-electrospray ionization mass spectrometry (ESIMS system for accurate mass measurement. One 96-well plate was used for a bioassay (AChE-inhibitory assay and detected the bioactivity and position of the relevant peak in the chromatogram. The positive well in the second 96-well plate was used for identification by LC-(+ ESIMS. Conclusion: As abovementioned, the AChE inhibitory constituents from P.fel-terrae by LC-bioassay-ESIMS were rapid identified. Liquid chromatography/ mass spectrometry (LC-MS screening detected the presence of six active compounds, identified as picfeltarraenin IA (1, picfeltarraenin IB (2, picfeltarraenin IV (3, picfeltarraenin X (4, picfeltarraenin XI (5, and one unknown compound. The structures were further determined by 13C NMR. The six compounds expressed stronger AChE inhibition than the known AChE inhibitorTacrine. Above all, the value of this LC-bioassay-ESIMS methodology is highlighted by the finding and structure elucidation of the active constituents from many other structural families of natural products.

  7. Use of viral promoters in mammalian cell-based bioassays: How reliable?

    OpenAIRE

    Gill-Sharma Manjit; Choudhuri Jyoti; Betrabet Shrikant S

    2004-01-01

    Abstract Cell-based bioassays have been suggested for screening of hormones and drug bioactivities. They are a plausible alternative to animal based methods. The technique used is called receptor/reporter system. Receptor/reporter system was initially developed as a research technique to understand gene function. Often reporter constructs containing viral promoters were used because they could be expressed with very 'high' magnitude in a variety of cell types in the laboratory. On the other h...

  8. Toxicity Assessment of Perchloroethylene and Intermediate Products after Advanced Oxidation Process by Daphnia Magna Bioassay

    OpenAIRE

    Mahdi Kargar; Kazem Naddafi; Ramin Nabizadeh

    2014-01-01

    Background and objective: Perchloroethylene is a chlorinated hydrocarbon used as a solvent in many industries and services activities such as dry cleaning and auto industry as degreasing. We carried out a bioassay using Daphnia Magna in order to determine the ecological effects of wastewater treatment through applying advanced oxidation processes (ultrasonic, ultraviolet irradiation and hydrogen peroxide processes) for removal of perchloroethylene. Materials and Methods: Due to the sensiti...

  9. Predictions for the outcome of rodent carcinogenicity bioassays: identification of trans-species carcinogens and noncarcinogens.

    OpenAIRE

    Tennant, R W; Spalding, J.

    1996-01-01

    Thirty chemicals or substances currently undergoing long-term carcinogenicity bioassays in rodents have been used in a project to further evaluate methods and information that may have the capability of predicting potential carcinogens. In our predictions the principal information used includes structural alerts and in vitro test results for Salmonella mutagenicity, relative subchronic toxicity, and the sites and types of pathology found in subchronic (90-day) studies. This group of chemicals...

  10. Mouse bioassay to assess oestrogenic and anti-oestrogenic compounds: Hydroxytamoxifen, Diethylstilbestrol and Genistein

    Czech Academy of Sciences Publication Activity Database

    Köhlerová, Eva; Škarda, Josef

    2004-01-01

    Roč. 51, č. 5 (2004), s. 209-217. ISSN 0931-184X R&D Projects: GA ČR GA524/02/0406; GA AV ČR IBS5045302; GA AV ČR KSK5020115 Institutional research plan: CEZ:AV0Z5045916 Keywords : bioassay * anti-oestrogens * oestrogenicity Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 0.471, year: 2004

  11. BRINE SHRIM LETHALITY BIOASSAY OF METHANOLIC CRUDE EXTRACTS OF TERMINALIA ARJUNA

    OpenAIRE

    Maruf Anayet and Mohammad Musarraf Hussain

    2012-01-01

    The aim of this work is to determine the cytotoxic activities of Terminalia arjuna (Family: Combretaceae) by brine shrimp lethality bioassay. The leaves of Terminalia arjuna were extracted with methanol and the methanolic extract was fractionated into three fractions by using organic solvents like n-hexane, ethyl acetate and chloroform. The n-hexane, ethyl acetate and chloroform soluble fractions of methanolic crude extract were screened for antitumor properties using brine shrimp lethality b...

  12. Bioassay for grooming effectiveness towards Varroa destructor mites in Africanized and Carniolan honey bees

    OpenAIRE

    Aumeier, Pia

    2001-01-01

    International audience Grooming behavior is considered a varroosis tolerance factor of Africanized honey bees, but this behavior is difficult to evaluate directly within the honey bee colony. A laboratory bioassay was developed to measure the intensity and effectiveness of grooming responses by worker bees artificially infested with one Varroa mite. At a study site in tropical Brazil, the sequence of seven well- defined grooming reactions towards mites of different colonial origin was comp...

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

    OpenAIRE

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

    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 sup...

  14. Acute toxicity bioassay with native plants to evaluate an oil spill

    OpenAIRE

    Vivien Pentreath; Elena González; Mercedes Barquín; Stella Maris Ríos; Susana Perales

    2015-01-01

    Plant bioassays are excellent tools for the evaluation of environmental risks. In particular the use of seeds of vascular plants is recommended due to their higher sensitivity. The aim of this study was to evaluate the behavior of native plants in order for them to be used as biological indicators of environmental oil pollution in relation to a standardized bioindicator. We analyzed the germination index (GI) of Lactuca sativa L., Atriplex lampa (Moq.) D.Dietri. and Prosopis denudans in thirt...

  15. Pathogenic fungi and Bio-control agents: Competitive bio-assay research

    OpenAIRE

    Olabiyi, T.I.; Ruocco, M.; Lanzuize, S.

    2014-01-01

    Fungi of the genus Trichoderma have a track record of being antagonist to quite of a number of agricultural important pathogens. Trichoderma have some unique characteristics that make it scientifically proven and suitable bio-control agents against varieties of pathogenic organism infecting economic food crops. Trichoderma has the advantage of being environment friendly and not hazardous to the health of human beings, livestock, soil and environment. Competitive bio-assay experiment was carri...

  16. Isolation of antibacterial compounds from Quercus dilatata L. through bioassay guided fractionation

    OpenAIRE

    Jamil Maryam; ul Haq Ihsan; Mirza Bushra; Qayyum Mazhar

    2012-01-01

    Abstract Background Four medicinal plants (Chrozophora hierosolymitana Spreng, Chrysanthemum leucanthemum L., Ephedra gerardiana Wall. ex Stapf, and Quercus dilatata L.) used by indigenous healers to treat various infectious diseases were selected for the present study. The major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation. Methods Seven methanolic extracts of the four plants we...

  17. Sensitive bioassay for detection of PPARα potentially hazardous ligands with gold nanoparticle probe

    International Nuclear Information System (INIS)

    Highlights: → We develop a sensitive and high throughput method to screen PPARα ligands. → This method is based on the ligand-receptor interaction on microplate. → The sensitivity is increased through sliver enhancement on captured gold nanoparticle probes. → There is a significant correlation between the bioassay and LC-MS for water spiked samples. - Abstract: There are so many kinds of peroxisome proliferator-activated receptor α (PPARα) ligands with hazardous effect for human health in the environment, such as certain herbicides, plasticizers and drugs. Among these agonists, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and mono-(2-ethylhexyl) phthalate (MEHP) are mostly investigated due to their persistence and accumulation in environment and their potential toxicity via PPARα. This investigation aims at developing a bioassay method to detect PPARα ligands based on the ligand-receptor interaction on microplate. PPARα, which formed heterodimers with retinoid X receptor-α (RXRα), were activated by PPARα ligands to form ligands-PPARα-RXRα complexes. Then the complexes were transferred into a microplate and captured via monoclonal anti-PPARα antibody. The PPARα responsive elements (PPRE) modified-gold nanoparticle probes were captured by the ligand-PPARα-RXRα complexes immobilized on the microplate, and then could be quantified through measuring the optical density after silver enhancement. The results showed that PFOS was quantified with a linear range from 100 pM to 1 μM and the detection limit was 10 pM. In addition to PFOS, PFOA and MEHP were also quantified within a proper range through the proposed bioassay. This bioassay was compared with that of liquid chromatography tandem-mass spectrometry (LC-MS) for water spiked samples with a significant correlation (r = 0.9893). This study provides a high-throughput detection method for PPARα ligands in microplate with high sensitivity and wide linear range. It may serve as

  18. Biological screening of selected Pacific Northwest forest plants using the brine shrimp (Artemia salina) toxicity bioassay.

    Science.gov (United States)

    Karchesy, Yvette M; Kelsey, Rick G; Constantine, George; Karchesy, Joseph J

    2016-01-01

    The brine shrimp (Artemia salina) bioassay was used to screen 211 methanol extracts from 128 species of Pacific Northwest plants in search of general cytotoxic activity. Strong toxicity (LC50  1000 µg/ml). Our subsequent studies of conifer heartwoods with strong activity confirm the assay's value for identifying new investigational leads for materials with insecticidal and fungicidal activity. PMID:27186474

  19. Promising Aedes aegypti Repellent Chemotypes Identified through Integrated QSAR, Virtual Screening, Synthesis, and Bioassay

    OpenAIRE

    Oliferenko, Polina V.; Oliferenko, Alexander A; Poda, Gennadiy I.; Osolodkin, Dmitry I; Girinath G. Pillai; Bernier, Ulrich R.; Tsikolia, Maia; Agramonte, Natasha M.; Clark, Gary G.; Linthicum, Kenneth J.; Katritzky, Alan R.

    2013-01-01

    Molecular field topology analysis, scaffold hopping, and molecular docking were used as complementary computational tools for the design of repellents for Aedes aegypti , the insect vector for yellow fever, chikungunya, and dengue fever. A large number of analogues were evaluated by virtual screening with Glide molecular docking software. This produced several dozen hits that were either synthesized or procured from commercial sources. Analysis of these compounds by a repellent bioassay resul...

  20. Recombinant Streptomyces clavuligerus strain including cas2 gene production and analysis its antibiotic overproduction by bioassay

    Directory of Open Access Journals (Sweden)

    Zohreh Hojati

    2014-03-01

    Full Text Available Background: Streptomyces clavuligerus is one of the most important strain that produce clavulanic acid that wildly used in combination of strong but sensitive to β-lactamase antibiotics in clinics. The cas2 is one of the important genes in the biosynthesis pathway of clavulanic acid. Materials and Methods: The recombinant construct pMTcas2 which contain cas2 gene is obtained from Isfahan University. Recombinant plasmid extracts from streptomyces lividans and confirm by enzyme digestion. The streptomyces clavuligerus protoplast was prepared and transformation was done by using polyethylene glycol. Transformation was confirmed by plasmid extraction and PCR using cas2 specific primers. Finally, bioassay method was used to survey the effect of extra copy of cas2 on clavulanic acid production. Result: Plasmid extraction was initially carried out and the structure of plasmid was confirmed by digestion. The typical white colony was seen on protoplast recovery culture containing thiostrepton antibiotic and gray spores were detected after one week. Plasmid extraction was done from transformed strain and transformation was confirmed by PCR. The results of the bioassay show that amplification of the cas2 gene in multicopy plasmids resulted in a 4.1 fold increase in clavulanic acid production. Conclusion: The bioassay was done and the diameters of zone of inhibition in control and sample were compared. The results of the bioassay show that amplification of the cas2 gene in multicopy plasmids resulted in a 4.1 fold increase in clavulanic acid production. Overproduction of clavulanic acid decreases the cost of its dependent drug production.

  1. Application of the CALUX bioassay for epidemiological study. Analyses of Belgian human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Wouwe, N. van; Debacker, N.; Sasse, A. [Scientific Institute of Public Health, Brussels (BE)] (and others)

    2004-09-15

    The CALUX bioassay is a promising screening method for the detection of dioxin-like compounds. The observed good sensitivity, low number of false negative results as well as the good correlations with the GC-HRMS TEQ-values in case of feed and food analyses allow this method to climb in the first assessment methods' scale. The low amount of sample needed in addition to those latest advantages suggest that the CALUX bioassay could be a good screening method for epidemiological studies. The Belgian epidemiological study concerning the possible effect of the dioxin incident on the body burden of the Belgian population was an opportunity to test this method in comparison to the gold reference one: the GC-HRMS. The first part of this abstract presents epidemiological parameters (sensibility, specificity,) of the CALUX bioassay using CALUX TEQ-values as estimators of the TEQ-values of the 17 PCDD/Fs. The second part examines epidemiological determinants observed for CALUX and GCHRMS TEQ-values.

  2. Bioassays as a tool for evaluating advanced oxidation processes in water and wastewater treatment.

    Science.gov (United States)

    Rizzo, Luigi

    2011-10-01

    Advanced oxidation processes (AOPs) have been widely used in water and wastewater treatment for the removal of organic and inorganic contaminants as well as to improve biodegradability of industrial wastewater. Unfortunately, the partial oxidation of organic contaminants may result in the formation of intermediates more toxic than parent compounds. In order to avoid this drawback, AOPs are expected to be carefully operated and monitored, and toxicity tests have been used to evaluate whether effluent detoxification takes place. In the present work, the effect of AOPs on the toxicity of aqueous solutions of different classes of contaminants as well as actual aqueous matrices are critically reviewed. The dualism toxicity-biodegradability when AOPs are used as pre-treatment step to improve industrial wastewater biodegradability is also discussed. The main conclusions/remarks include the followings: (i) bioassays are a really useful tool to evaluate the dangerousness of AOPs as well as to set up the proper operative conditions, (ii) target organisms for bioassays should be chosen according to the final use of the treated water matrix, (iii) acute toxicity tests may be not suitable to evaluate toxicity in the presence of low/realistic concentrations of target contaminants, so studies on chronic effects should be further developed, (iv) some toxicity tests may be not useful to evaluate biodegradability potential, in this case more suitable tests should be applied (e.g., activated sludge bioassays, respirometry). PMID:21722938

  3. Fluorescence-Based Bioassays for the Detection and Evaluation of Food Materials

    Directory of Open Access Journals (Sweden)

    Kentaro Nishi

    2015-10-01

    Full Text Available 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.

  4. A bioassay for the detection of perchlorate in the ppb range.

    Science.gov (United States)

    Heinnickel, Mark; Smith, Stephen C; Koo, Jonathan; O'Connor, Susan M; Coates, John D

    2011-04-01

    A bioassay for the determination of ppb (μg·L(-1)) concentrations of perchlorate has been developed and is described herein. The assay uses the enzyme perchlorate reductase (PR) from the perchlorate-reducing organism Dechloromonas agitata in purified and partially purified forms to detect perchlorate. The redox active dye phenazine methosulfate (PMS) is shown to efficiently shuttle electrons to PR from NADH. Perchlorate can be determined indirectly by monitoring NADH oxidization by PR. To lower the detection limit, we have shown that perchlorate can be concentrated on a solid-phase extraction (SPE) column that is pretreated with the cation decyltrimethylammonium bromide (DTAB). Perchlorate is eluted from these columns with a solution of 2 M NaCl and 200 mM morpholine propane sulfonic acid (MOPS, pH 12.5). By washing these columns with 15 mL of 2.5 mM DTAB and 15% acetone, contaminating ions, such as chlorate and nitrate, are removed without affecting the bioassay. Because of the effect of complex matrices on the SPE columns, the method of standard additions is used to analyze tap water and groundwater samples. The efficacy of the developed bioassay was demonstrated by analyzing samples from 2-17000 ppb in deionized lab water, tap water, and contaminated groundwater. PMID:21384912

  5. Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Villarini, M.; Fatigoni, C.; Dominici, L.; Maestri, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Ederli, L.; Pasqualini, S. [Department of Applied Biology, University of Perugia, I-06121 (Italy); Monarca, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Moretti, M., E-mail: massimo.moretti@unipg.i [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy)

    2009-12-15

    Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone no. 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air. - Plant bioassays used to explore in situ the correlation between air pollution and genotoxicity.

  6. A rapid bioassay to monitor murine leukemia virus infection in mice using cellular gp71 binding

    International Nuclear Information System (INIS)

    A rapid and sensitive bioassay based on the availability of cell surface receptors for the binding of purified envelope glycoprotein, gp71, of Rauscher murine leukemia virus (R-MuLV) was developed to serially monitor viral-induced leukemogenesis in individual BALB/cAnN mice. The specificity of the bioassay was demonstrated by the competition of [125I]gp71 cellular binding with murine ecotropic viruses, purified unlabelled R-MuLV envelope glycoprotein and by antiserum to R-MuLV gp71. In contrast, there was no effect on the [125I]gp71 binding level with the addition of murine xenotropic viruses, R-MuLV p30, or several other proteins. The [125I]gp71 binding level of circulating leukocytes was significantly (P < 0.05) reduced in mice after R-MuLV infection. The reduction of cellular gp71 binding developed in two stages and the latter stage was highly dependent (P < 0.05) on circulating infections virus titer. Using this technique, the gp71 cellular binding levels of 48-60 individual mice can be assayed in a 4 h period. The advantages of this bioassay compared to standard immunological and tissue culture techniques used in studying retrovirus expression and viral-cell interactions are discussed. (Auth.)

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

    Directory of Open Access Journals (Sweden)

    Alison K. Heather

    2013-02-01

    Full Text Available 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.

  8. Selection of a bioassay battery to assess toxicity in the affluents and effluents of three water-treatment plants

    OpenAIRE

    Paola Bohórquez-Echeverry; Marcela Duarte-Castañeda; Nubia León-López; Claudia Campos-Pinilla; Fabián Caicedo-Carrascal; Myriam Vásquez-Vásquez

    2012-01-01

    The assessment of water quality includes the analysis of both physical-chemical and microbiological parameters. However,none of these evaluates the biological effect that can be generated in ecosystems or humans. In order to define the most suitable organismsto evaluate the toxicity in the affluent and effluent of three drinking-water treatment plants, five acute toxicity bioassays were used,incorporating three taxonomic groups of the food chain. Materials and methods. The bioassays used were...

  9. Sensitivity bioassays of the Cnesterodon decemmaculatus and Pimephales promelasin a series of samples of effluent and reference toxicant

    OpenAIRE

    Gustavo Saona; Agustín Carnikian; Martín Spósito; Patricia Baklayan; Julio Espínola

    2015-01-01

    This study compared the toxicological sensitivity quantified by the 50% lethal dose of acute toxicity bioassays of Cnesterodon decemmaculatusand Pimephales promelasin benchmark exposure to toxic industrial effluents, wastewater effluents and reference toxicants. At the same time, the toxicological sensitivity of C. decemmaculatusrelated to the size was assayed. Both species were analyzed with 16 bioassays mated by the same substance or compound and a good agreement rL= 0.75 was observed. No s...

  10. Beoordeling van gereinigde grond. V. Toepassing van bioassays met planten en regenwormen op verontreinigde en gereinigde gronden

    OpenAIRE

    Gestel CAM van; Dirven-van Breemen EM; Kamerman JW

    1992-01-01

    Within the framework of the project "Evaluation of decontaminated soil", the applicability of bioassays with earthworms and plants for the quality assessment of decontaminated soil is investigated. In the final phase of this project, bioassays with earthworms and plants (radish, lettuce) developed earlier, were applied to a number of polluted and decontaminated soils. As earlier studies demonstrated that bioavailability of metals increased due to clean-up operations, the decontamina...

  11. Performance characteristics of bioassay UV-spectrophotometry and high perfomance liquid chromatographic determination of gatifloxacin in tablets

    OpenAIRE

    Cristiani Capistrano Gonçalves de Oliveira Lopes; Hérida Regina Nunes Salgado

    2008-01-01

    The microbiological bioassay, UV-spectrophotometry and HPLC methods for assaying gatifloxacin in tablets were compared. Validation parameters such as linearity, precision, accuracy, limit of detection and limit of quantitation were determined. Beer's law was obeyed in the ranges 4.0-14.0 μg/mL for HPLC and UV-spectrophotometric method, and 4.0-16.0 μg/mL for bioassay. All methods were reliable within acceptable limits for antibiotic pharmaceutical preparations being accurate, precis...

  12. Quality assurance exercise for estimating low-levels of alpha emitters in urine samples: performance of Trombay's bioassay laboratory

    International Nuclear Information System (INIS)

    As a part of quality assurance, Trombay's bioassay laboratory took part in the international intercomparison exercise organized by International Atomic Energy Agency (IAEA) for estimating low-levels of alpha emitters (234U, 238U, 239+240Pu and 241Am) in urine samples. In this paper, performance of the Trombay's bioassay laboratory in the intercomparison exercise is presented. The results submitted by the laboratory were found to be in good agreement with the organizers (spiked) values. (author)

  13. A rapid and high-throughput quantum dots bioassay for monitoring of perfluorooctane sulfonate in environmental water samples

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jiong; Wan Yanjian; Li Yuanyuan; Zhang Qiongfang; Xu Shunqing [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China); Zhu Huijun [Cranfield Health, Cranfield University, Kempston, Bedfordshire, MK43 0AL (United Kingdom); Shu Baihua, E-mail: shubaihua@hotmail.com [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China)

    2011-05-15

    Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPAR{alpha}), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPAR{alpha}-RXR{alpha}. It can be determined indirectly by immobilizing PPAR{alpha}-RXR{alpha}-PFOS complex to another plate coated with PPAR{alpha} antibody and subsequent measuring the level of PPAR{alpha}-RXR{alpha} by using biotin-modified PPAR{alpha}-RXR{alpha} probes-quantum dots-streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L{sup -1} with linear range between 2.5 ng L{sup -1} and 75 ng L{sup -1}. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS. - We developed a rapid and high-throughput bioassay for monitoring of PFOS in environmental water samples. - Highlights: > We developed a rapid and high-throughput bioassay for monitoring of PFOS in water. > We detected the PFOS concentration of water samples by two methods. > The bioassay is effective for evaluating PFOS contamination level.

  14. A rapid and high-throughput quantum dots bioassay for monitoring of perfluorooctane sulfonate in environmental water samples

    International Nuclear Information System (INIS)

    Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPARα), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPARα-RXRα. It can be determined indirectly by immobilizing PPARα-RXRα-PFOS complex to another plate coated with PPARα antibody and subsequent measuring the level of PPARα-RXRα by using biotin-modified PPARα-RXRα probes-quantum dots-streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L-1 with linear range between 2.5 ng L-1 and 75 ng L-1. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS. - We developed a rapid and high-throughput bioassay for monitoring of PFOS in environmental water samples. - Highlights: → We developed a rapid and high-throughput bioassay for monitoring of PFOS in water. → We detected the PFOS concentration of water samples by two methods. → The bioassay is effective for evaluating PFOS contamination level.

  15. Comparison of chronic toxicity and carcinogenicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in two-year bioassays in female Sprague-Dawley rats

    OpenAIRE

    Walker, Nigel J.; Wyde, Michael E.; Fischer, Lawrence J.; Nyska, Abraham; Bucher, John R

    2006-01-01

    The cancer bioassay for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) conducted by the Dow Chemical company in the mid 70s been used extensively for conducting quantitative cancer risk assessments for human exposure to TCDD. More recently the National Toxicology Program (NTP) conducted a cancer bioassay of similar design as part of its evaluation of the dioxin TEF methodology. This report compares the design and the results of these two cancer bioassays. This comparison confirms, in most cases, ...

  16. Bioassay of circulating luteinizing hormone in the rhesus monkey: comparison with radioimmunoassay during physiological changes

    International Nuclear Information System (INIS)

    The concentration of biologically active LH in Rhesus monkey (Macaca mulatta) serum was measured by a highly sensitive bioassay based upon testosterone production by dispersed rat interstitial cells. The sensitivity of the in vitro bioassay was equal to or higher than that of radioimmunoassay, with detection limits of 0.1 mIU of human menopausal gonadotropin (hMG) or 10 ng of a Rhesus pituitary gonadotropin preparation (LER-1909-2). Parallel dose-response curves were obtained for hMG and Rhesus monkey pituitary gonadotropin. The method permits bioassay of LH in 20--100 μl of serum from adult male monkeys, and from female monkeys during the follicular and luteal phases of the menstrual cycle. Bioactive LH concentrations could be assayed in 0.25 to 5 μl of serum from mid-cycle, postmenopausal, and castrated female monkeys. Serum LH was undetectable in two hypophysectomized adult female monkeys and six intact immature animals, and was 13 +- 6 (SD) mIU/ml in adult male monkeys. In adult females, follicular phase LH levels ranged from 17 to 169 mIU/ml, with a mean of 76 +- 52 mIU/ml. The midcycle LH peak was 1738 +- 742 mIU/ml and the luteal phase values ranged from 6-47 mIU/ml, with a mean of 35 +- 5 mIU/ml. Serum LH concentrations ranged from 100 to 900 mIU/ml in two menopausal females, and from 590--1480 mIU/ml in castrated females. Treatment of castrated female monkeys with estrogen plus progesterone produced an initial two-fold rise in sepum LH within 3 days, followed by a gradual decline to one-fourth to one-tenth of the initial levels after 10 days of treatment. Serum LH was suppressed to undetectable levels during the third week, and remained so for the duration of the 60-day treatment period

  17. Guidance document for prepermit bioassay testing of low-level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, S.L.; Harrison, F.L.

    1990-11-01

    In response to the mandate of Public Law 92-532, the Marine Protection, Research, and Sanctuaries Act (MPRSA) of 1972, as amended, the Environmental Protection Agency (EPA) has developed a program to promulgate regulations and criteria to control the ocean disposal of radioactive wastes. The EPA seeks to understand the mechanisms for biological response of marine organisms to the low levels of radioactivity that may arise from the release of these wastes as a result of ocean-disposal practices. Such information will play an important role in determining the adequacy of environmental assessments provided to the EPA in support of any disposal permit application. Although the EPA requires packaging of low-level radioactive waste to prevent release during radiodecay of the materials, some release of radioactive material into the deep-sea environment may occur when a package deteriorates. Therefore, methods for evaluating the impact on biota are being evaluated. Mortality and phenotypic responses are not anticipated at the expected low environmental levels that might occur if radioactive materials were released from the low-level waste packages. Therefore, traditional bioassay systems are unsuitable for assessing sublethal effects on biota in the marine environment. The EPA Office of Radiation Programs (ORP) has had an ongoing program to examine sublethal responses to radiation at the cellular level, using cytogenetic end points. This technical guidance report represents prepermit bioassay procedures that potentially may be applicable to the assessment of effects from a mixture of radionuclides that could be released from a point source at the ocean bottom. Methodologies along with rationale and a discussion of uncertainty are presented for the sediment benthic bioassay protocols identified in this report.

  18. Guidance document for prepermit bioassay testing of low-level radioactive waste

    International Nuclear Information System (INIS)

    In response to the mandate of Public Law 92-532, the Marine Protection, Research, and Sanctuaries Act (MPRSA) of 1972, as amended, the Environmental Protection Agency (EPA) has developed a program to promulgate regulations and criteria to control the ocean disposal of radioactive wastes. The EPA seeks to understand the mechanisms for biological response of marine organisms to the low levels of radioactivity that may arise from the release of these wastes as a result of ocean-disposal practices. Such information will play an important role in determining the adequacy of environmental assessments provided to the EPA in support of any disposal permit application. Although the EPA requires packaging of low-level radioactive waste to prevent release during radiodecay of the materials, some release of radioactive material into the deep-sea environment may occur when a package deteriorates. Therefore, methods for evaluating the impact on biota are being evaluated. Mortality and phenotypic responses are not anticipated at the expected low environmental levels that might occur if radioactive materials were released from the low-level waste packages. Therefore, traditional bioassay systems are unsuitable for assessing sublethal effects on biota in the marine environment. The EPA Office of Radiation Programs (ORP) has had an ongoing program to examine sublethal responses to radiation at the cellular level, using cytogenetic end points. This technical guidance report represents prepermit bioassay procedures that potentially may be applicable to the assessment of effects from a mixture of radionuclides that could be released from a point source at the ocean bottom. Methodologies along with rationale and a discussion of uncertainty are presented for the sediment benthic bioassay protocols identified in this report

  19. Evaluation of internal exposure of nuclear medicine staff through in vivo and in vitro bioassay techniques

    International Nuclear Information System (INIS)

    The manipulation of a wide variety of unsealed sources in Nuclear Medicine results in a significant risk of internal exposure of the workers. 131I should be highlighted among the most frequently used radionuclides because of its large application for diagnosis and therapy of thyroid diseases. The increasing use of radionuclides for medical purposes creates a demand for feasible methodologies to perform occupational control of internal contamination. Currently in Brazil, there are ∼300 nuclear medicine centres in operation but individual monitoring is still restricted to the control of external exposure. This work presents the development of in vivo and in vitro bioassay techniques aimed to quantify incorporation of radionuclides used in Nuclear Medicine. It is also presented the results of a preliminary survey of internal exposure of a group of workers involved in the preparation of therapeutic doses of 131I. Workers were monitored with a gamma camera available in the Nuclear Medicine Service of the University Hospital of Rio de Janeiro and at the Institute of Radiation Protection and Dosimetry Whole-Body Counter (IRDWBC). The in vivo detection systems were calibrated with a neck-thyroid phantom developed in IRD. Urine samples from radiopharmacy workers were collected after preparation and administration of therapeutic doses (10-250 mCi) of 131I and measured with a HPGe detection system available in the Bioassay Laboratory of IRD. The results show that the bioassay methods developed in this work present enough sensitivity for routine monitoring of nuclear medicine workers. All workers monitored in this survey presented positive results for 131I in urine samples and two workers presented detectable activities in thyroid when measured at the IRD-WBC. The highest committed effective dose per preparation was estimated to be 17 μSv. (authors)

  20. A novel method for standardized application of fungal spore coatings for mosquito exposure bioassays

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2010-01-01

    Full Text Available Abstract Background Interest in the use of fungal entomopathogens against malaria vectors is growing. Fungal spores infect insects via the cuticle and can be applied directly on the insect to evaluate infectivity. For flying insects such as mosquitoes, however, application of fungal suspensions on resting surfaces is more realistic and representative of field settings. For this type of exposure, it is essential to apply specific amounts of fungal spores homogeneously over a surface for testing the effects of fungal dose and exposure time. Contemporary methods such as spraying or brushing spore suspensions onto substrates do not produce the uniformity and consistency that standardized laboratory assays require. Two novel fungus application methods using equipment developed in the paint industry are presented and compared. Methods Wired, stainless steel K-bars were tested and optimized for coating fungal spore suspensions onto paper substrates. Different solvents and substrates were evaluated. Two types of coating techniques were compared, i.e. manual and automated coating. A standardized bioassay set-up was designed for testing coated spores against malaria mosquitoes. Results K-bar coating provided consistent applications of spore layers onto paper substrates. Viscous Ondina oil formulations were not suitable and significantly reduced spore infectivity. Evaporative Shellsol T solvent dried quickly and resulted in high spore infectivity to mosquitoes. Smooth proofing papers were the most effective substrate and showed higher infectivity than cardboard substrates. Manually and mechanically applied spore coatings showed similar and reproducible effects on mosquito survival. The standardized mosquito exposure bioassay was effective and consistent in measuring effects of fungal dose and exposure time. Conclusions K-bar coating is a simple and consistent method for applying fungal spore suspensions onto paper substrates and can produce coating layers

  1. Using a macroalgal δ15N bioassay to detect cruise ship waste water effluent inputs

    International Nuclear Information System (INIS)

    Highlights: → Green macroalgae exposed to nutrient solutions exhibited changes in tissue 15N signatures. → Macroalgae exhibited no fractionation with NO3 and slight fractionation with NH4. → Algae exposed to cruise ship waste water had increased tissue δ15N indicating a heavy N source. → Field bioassays exhibited decreased δ15N indicating isotopically light riverine δ15N-NO3 was likely the dominant N source. → Algal bioassays could not detect a δ15N cruise ship waste water signal in this system. - Abstract: Green macroalgae bioassays were used to determine if the δ15N signature of cruise ship waste water effluent (CSWWE) could be detected in a small harbor. Opportunistic green macroalgae (Ulva spp.) were collected, cultured under nutrient depleted conditions and characterized with regard to N content and δ15N. Samples of algae were used in controlled incubations to evaluate the direction of isotope shift from exposure to CSWWE. Algae samples exposed to CSWWE exhibited an increase of 1-2.5 per mille in δ15N values indicating that the CSWWE had an enriched isotope signature. In contrast, algae samples exposed to field conditions exhibited a significant decrease in the observed δ15N indicating that a light N source was used. Isotopically light, riverine nitrogen derived from N2-fixing trees in the watershed may be a N source utilized by algae. These experiments indicate that the δ15N CSWWE signature was not detectable under the CSWWE loading conditions of this experiment.

  2. Development of marine sediment bioassays and toxicity tests for monitoring and regulation in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Thain, J.; Matthiessen, P.

    1995-12-31

    There is a need in Europe and elsewhere for a broad suite of whole-sediment bioassays and toxicity tests which can be used for routine monitoring and assessment of the marine environment and for evaluating the toxic effects of chemicals which may find their way into sediments. Until recently, few European species had been incorporated into such tests but the availability of suitable methodologies is now increasing rapidly. Perhaps the most important recent activity in this area consisted of an international ring test of acute sediment toxicity test methods which was organized by the Oslo and Paris Commissions in 1993, using up to 4 offshore chemicals as test materials. It evaluated the performance of 4 acute (5--10 day) tests involving: the sea urchin Echinocardium cordatum, the bivalve mollusc Abra alba, the amphipod crustacean Corophium volutator, and the polychaete worm Arenicola marina. The ring test concluded that the C. volutator test was the most appropriate for evaluating offshore chemicals, but all these methods are now widely used in Europe, both as toxicity tests and as bioassays. For example, the A. marina procedure (which has both lethal and sublethal endpoints), in combination with the C. volutator method, is now routinely used in the UK for monitoring the toxicity of estuarine sediments. Further activities are in progress. Perhaps the most important is the development of chronic marine sediment tests and bioassays which can be used to assess the long-term effects of the many sedimentary contaminants which are able to persist in this type of habitat and possibly cause delayed effects on the growth and reproduction, etc. of benthic fauna.

  3. A rapid radio-bioassay method for strontium estimation in nuclear/radiological emergencies

    International Nuclear Information System (INIS)

    Strontium (Sr) is a by-product of the nuclear fission of uranium and plutonium in nuclear reactors and nuclear weapons. It is an important radionuclide in spent nuclear fuel and radioactive waste and is considered as one of the most hazardous constituents of nuclear wastes. Also during a nuclear/radiological emergency, workers as well as members of the public may get internally contaminated with Sr. Hence, a truly rapid radio-bioassay method will be needed to screen a large number of people for assessment of internal contamination and facilitate decision making on subsequent medical intervention. The current precipitation method used at Bioassay Lab., BARC, Trombay is quite lengthy and laborious. Efforts are being made to optimize bioassay methods at BARC using solid extraction chromatography (SEC) technique for emergency response. The present work reports standardization of SEC using Sr-Spec (Sr-Specific, make Eichrom Technologies, Darien, Illinois, USA) resin for rapid estimation of Sr in urine samples. Adsorbed Sr is eluted from the resin using 0.05M HNO3, precipitated as carbonate and estimated using a low background gas flow Geiger-Müller counter (make ECIL, Hyderabad, India). The average recovery of stable Sr is ∼ 80% and comparable to radioactive recovery observed in spiked samples. The minimum detectable activity (MDA) achieved by this technique is ∼ 4 mBq/mL for 90Sr that is well below the required generic emergency action level of 19 Bq for 20 mL urine sample. The advantage of this method is its simplicity, fast turnaround time and an increase in the sample throughput. (author)

  4. Fast and accurate semantic annotation of bioassays exploiting a hybrid of machine learning and user confirmation.

    Science.gov (United States)

    Clark, Alex M; Bunin, Barry A; Litterman, Nadia K; Schürer, Stephan C; Visser, Ubbo

    2014-01-01

    Bioinformatics and computer aided drug design rely on the curation of a large number of protocols for biological assays that measure the ability of potential drugs to achieve a therapeutic effect. These assay protocols are generally published by scientists in the form of plain text, which needs to be more precisely annotated in order to be useful to software methods. We have developed a pragmatic approach to describing assays according to the semantic definitions of the BioAssay Ontology (BAO) project, using a hybrid of machine learning based on natural language processing, and a simplified user interface designed to help scientists curate their data with minimum effort. We have carried out this work based on the premise that pure machine learning is insufficiently accurate, and that expecting scientists to find the time to annotate their protocols manually is unrealistic. By combining these approaches, we have created an effective prototype for which annotation of bioassay text within the domain of the training set can be accomplished very quickly. Well-trained annotations require single-click user approval, while annotations from outside the training set domain can be identified using the search feature of a well-designed user interface, and subsequently used to improve the underlying models. By drastically reducing the time required for scientists to annotate their assays, we can realistically advocate for semantic annotation to become a standard part of the publication process. Once even a small proportion of the public body of bioassay data is marked up, bioinformatics researchers can begin to construct sophisticated and useful searching and analysis algorithms that will provide a diverse and powerful set of tools for drug discovery researchers. PMID:25165633

  5. Development of a cell-based bioassay for phospholipase A2-triggered liposomal drug release.

    Directory of Open Access Journals (Sweden)

    Ahmad Arouri

    Full Text Available The feasibility of exploiting secretory phospholipase A2 (sPLA2 enzymes, which are overexpressed in tumors, to activate drug release from liposomes precisely at the tumor site has been demonstrated before. Although the efficacy of the developed formulations was evaluated using in vitro and in vivo models, the pattern of sPLA2-assisted drug release is unknown due to the lack of a suitable bio-relevant model. We report here on the development of a novel bioluminescence living-cell-based luciferase assay for the monitoring of sPLA2-triggered release of luciferin from liposomes. To this end, we engineered breast cancer cells to produce both luciferase and sPLA2 enzymes, where the latter is secreted to the extracellular medium. We report on setting up a robust and reproducible bioassay for testing sPLA2-sensitive, luciferin remote-loaded liposomal formulations, using 1,2-distearoyl-sn-glycero-3-phosphatidylcholine/1,2-distearoyl-sn-glycero-3-phosphatidylglycerol (DSPC/DSPG 7:3 and DSPC/DSPG/cholesterol 4:3:3 as initial test systems. Upon their addition to the cells, the liposomes were degraded almost instantaneously by sPLA2 releasing the encapsulated luciferin, which provided readout from the luciferase-expressing cells. Cholesterol enhanced the integrity of the formulation without affecting its susceptibility to sPLA2. PEGylation of the liposomes only moderately broadened the release profile of luciferin. The provided bioassay represents a useful tool for monitoring active drug release in situ in real time as well as for testing and optimizing of sPLA2-sensitive lipid formulations. In addition, the bioassay will pave the way for future in-depth in vitro and in vivo studies.

  6. Applicability of the CALUX bioassay for screening of dioxin levels in human milk samples

    DEFF Research Database (Denmark)

    Laier, P.; Cederberg, Tommy Licht; Larsen, John Christian; Vinggaard, A.M.

    2003-01-01

    The CALUX (chemically activated luciferase expression) bioassay based on rat hepatoma (H4IIE) cells is a sensitive assay for the detection of Ah receptor agonists like 2,3,7,8-substituted chlorinated dibenzo-p-dioxins and dibenzofurans and related PCBs. In this paper, the assay was optimized and...... additively, indicating that the usual assumption of additivity in the risk assessment process is valid. In general the relative potencies (REPs) of the single agents were in accordance with their TEFs assigned by the World Health Organisation, except for the mono-ortho-substituted PCB118 that had a 40-fold...

  7. Sensitive bioassay for detection of PPAR{alpha} potentially hazardous ligands with gold nanoparticle probe

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Wei; Wan, Yan-Jian [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China); Wang, Xianliang [Division of Environmental Pollution and Human Health, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Li, Yuan-yuan; Yang, Wen-Jie; Wang, Chun-Xiang [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China); Xu, Shun-qing, E-mail: shunqing@mails.tjmu.edu.cn [Minister of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, Hubei Province 430030 (China)

    2011-09-15

    Highlights: {yields} We develop a sensitive and high throughput method to screen PPAR{alpha} ligands. {yields} This method is based on the ligand-receptor interaction on microplate. {yields} The sensitivity is increased through sliver enhancement on captured gold nanoparticle probes. {yields} There is a significant correlation between the bioassay and LC-MS for water spiked samples. - Abstract: There are so many kinds of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) ligands with hazardous effect for human health in the environment, such as certain herbicides, plasticizers and drugs. Among these agonists, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and mono-(2-ethylhexyl) phthalate (MEHP) are mostly investigated due to their persistence and accumulation in environment and their potential toxicity via PPAR{alpha}. This investigation aims at developing a bioassay method to detect PPAR{alpha} ligands based on the ligand-receptor interaction on microplate. PPAR{alpha}, which formed heterodimers with retinoid X receptor-{alpha} (RXR{alpha}), were activated by PPAR{alpha} ligands to form ligands-PPAR{alpha}-RXR{alpha} complexes. Then the complexes were transferred into a microplate and captured via monoclonal anti-PPAR{alpha} antibody. The PPAR{alpha} responsive elements (PPRE) modified-gold nanoparticle probes were captured by the ligand-PPAR{alpha}-RXR{alpha} complexes immobilized on the microplate, and then could be quantified through measuring the optical density after silver enhancement. The results showed that PFOS was quantified with a linear range from 100 pM to 1 {mu}M and the detection limit was 10 pM. In addition to PFOS, PFOA and MEHP were also quantified within a proper range through the proposed bioassay. This bioassay was compared with that of liquid chromatography tandem-mass spectrometry (LC-MS) for water spiked samples with a significant correlation (r = 0.9893). This study provides a high-throughput detection

  8. Gamma radiation and ems treatment of black cumin cultivars for mutational bioassays

    International Nuclear Information System (INIS)

    Ten different types of chlorophyll mutations were induced in two cultivars of black cumin (Nigella sativa L.) after gamma irradiation and EMS treatment. Mutation frequency was proportional to dose for gamma rays, but not for EMS. Higher doses of gamma rays and lower concentration/duration of EMS were most efficient. Difference in the response of both cultivars due to mutagenic treatment indicate variation in the genetic architecture of the two cultivars. Origin and use of black cumin cultivars for mutagen bioassays studies are discussed

  9. Toxicity assessment of effluent from flash light manufacturing industry by bioassay tests in Trigonella foenumgracum.

    Science.gov (United States)

    Kumari, Narendra; Kumar, Sanjeev; Bauddh, Kuldeep; Dwivedi, Neetu; Singh, D P; Barman, S C

    2014-11-01

    A rapid bioassay test was conducted to study heavy metal accumulation and biochemical changes in Trigonella foenumgracum (methi) irrigated with 25, 50, 75 and 100% of effluent from flash light manufacturing industry at 60 days after sowing. Total metal concentration in effluent samples was: Cr = 0.12 effluent followed by a decrease at higher concentration as compared to their respective control.An enhanced lipid peroxidation in the treated plants was observed, which was evident by increased level of antioxidants: proline, cysteine, malondialdehyde and ascorbic acid content. The treated plants accumulated metals in the following order: Cu > Pb > Cr > Cd in the roots and shoots. PMID:25522513

  10. NTP Workshop: Animal Models for the NTP Rodent Cancer Bioassay: Stocks and Strains - Should We Switch?

    OpenAIRE

    King-Herbert, Angela; Thayer, Kristina

    2006-01-01

    The National Toxicology Program (NTP) hosted a workshop, “Animal Models for the NTP Rodent Cancer Bioassay: Strains & Stocks -- Should We Switch?” on June 16-17, 2005, at the National Institute of Environmental Health Sciences (NIEHS) in Research Triangle Park, NC. The workshop’s objectives were to determine (1) whether the currently used models, the F344/N rat and B6C3F1/N mouse, continue to be appropriate to identify substances that may pose a carcinogenic hazard for humans and (2) whether ...

  11. 'In-vivo' and bioassay results from two contrasting cases of plutonium-239 inhalation

    International Nuclear Information System (INIS)

    'In-vivo' and bioassay measurements following two incidents involving plutonium-239 inhalation are described and contrasted. Incident 1, involving the inhalation of insoluble plutonium oxide, resulted in a lung content of about 20 nCi after the initial clearance. Urine excretion was negligible and the estimation of exposure was based on 'in-vivo' data and faecal excretion. Incident,2, involving the inhalation of soluble plutonium, proved negligible and the estimation of exposure, based on urinary excretion, was 0.6 nCi. (author)

  12. An adaptive nonparametric method in benchmark analysis for bioassay and environmental studies

    OpenAIRE

    Bhattacharya, Rabi; Lin, Lizhen

    2010-01-01

    We present a novel nonparametric method for bioassay and benchmark analysis in risk assessment, which averages isotonic MLEs based on disjoint subgroups of dosages. The asymptotic theory for the methodology is derived, showing that the MISEs (mean integrated squared error) of the estimates of both the dose-response curve F and its inverse F−1 achieve the optimal rate O(N−4/5). Also, we compute the asymptotic distribution of the estimate ζ~p of the effective dosage ζp = F−1 (p) which is shown ...

  13. Single-core magnetic markers in rotating magnetic field based homogeneous bioassays and the law of mass action

    Energy Technology Data Exchange (ETDEWEB)

    Dieckhoff, Jan, E-mail: j.dieckhoff@tu-bs.de [Institut fuer Elektrische Messtechnik und Grundlagen der Elektrotechnik, TU Braunschweig, Braunschweig (Germany); Schrittwieser, Stefan; Schotter, Joerg [Molecular Diagnostics, AIT Austrian Institute of Technology, Vienna (Austria); Remmer, Hilke; Schilling, Meinhard; Ludwig, Frank [Institut fuer Elektrische Messtechnik und Grundlagen der Elektrotechnik, TU Braunschweig, Braunschweig (Germany)

    2015-04-15

    In this work, we report on the effect of the magnetic nanoparticle (MNP) concentration on the quantitative detection of proteins in solution with a rotating magnetic field (RMF) based homogeneous bioassay. Here, the phase lag between 30 nm iron oxide single-core particles and the RMF is analyzed with a fluxgate-based measurement system. As a test analyte anti-human IgG is applied which binds to the protein G functionalized MNP shell and causes a change of the phase lag. The measured phase lag changes for a fixed MNP and a varying analyte concentration are modeled with logistic functions. A change of the MNP concentration results in a nonlinear shift of the logistic function with the analyte concentration. This effect results from the law of mass action. Furthermore, the bioassay results are used to determine the association constant of the binding reaction. - Highlights: • A rotating magnetic field based homogeneous bioassay concept was presented. • Here, single-core iron oxide nanoparticles are applied as markers. • The impact of the particle concentration on the bioassay results is investigated. • The relation between particle concentration and bioassay sensitivity is nonlinear. • This finding can be reasonably explained by the law of mass action.

  14. Single-core magnetic markers in rotating magnetic field based homogeneous bioassays and the law of mass action

    International Nuclear Information System (INIS)

    In this work, we report on the effect of the magnetic nanoparticle (MNP) concentration on the quantitative detection of proteins in solution with a rotating magnetic field (RMF) based homogeneous bioassay. Here, the phase lag between 30 nm iron oxide single-core particles and the RMF is analyzed with a fluxgate-based measurement system. As a test analyte anti-human IgG is applied which binds to the protein G functionalized MNP shell and causes a change of the phase lag. The measured phase lag changes for a fixed MNP and a varying analyte concentration are modeled with logistic functions. A change of the MNP concentration results in a nonlinear shift of the logistic function with the analyte concentration. This effect results from the law of mass action. Furthermore, the bioassay results are used to determine the association constant of the binding reaction. - Highlights: • A rotating magnetic field based homogeneous bioassay concept was presented. • Here, single-core iron oxide nanoparticles are applied as markers. • The impact of the particle concentration on the bioassay results is investigated. • The relation between particle concentration and bioassay sensitivity is nonlinear. • This finding can be reasonably explained by the law of mass action

  15. Evaluation of genotoxicity from low exposure rates of ionizing radiation by using Trad-MCN bioassay

    International Nuclear Information System (INIS)

    The biomonitoring has been recognized as an important tool in the field of environmental studies. Biological assays have been used to evaluate genotoxic agents present in the environment. Among the bioassays using plants, the micronucleus tests of Tradescantia sp. (Trad-MCN) has shown sensitivity to several environmental conditions, including radiation. Several studies have demonstrated that Tradescantia sp. is sensitive to the harmful effects of X-rays, internal and external radioisotopic sources and cosmic rays. The toxicity is evaluated by observing the frequency of broken chromosomes presented as a small rounded structure in the pollen cells (tetrads), called micronucleus. The present study was developed in Centro Experimental Aramar where, since the 80's, an Environmental Monitoring Program has been carried out by the Radioecological Laboratory. The purpose of this work was to evaluate, by using the Trad-MCN bioassay, the genotoxicity from low exposure rates of ionizing radiation on Tradescantia pallida inflorescences exposed to a uranium ore, in a closed dynamic system. The plants were also submitted to a control exposure with filtered air (negative control). The assay was developed according to the usual protocol. Micronuclei frequencies were compared using Kruskal-Wallis variance analysis. The negative control presented a significantly different micronuclei frequency from all the groups exposed to radiation (P -1). The obtained results indicated that T. pallida is sensitive to ionizing radiation even in low exposure rates and it can be used for in vitro environmental monitoring(author)

  16. Bioassay standardization for the detection of allelopathic compounds and environmental toxicants using lettuce

    Directory of Open Access Journals (Sweden)

    Mateus Salomão Simões

    2013-09-01

    Full Text Available The purpose of this study was to assess different experimental conditions to determine a protocol for bioassays based on seed germination and early seedling growth using lettuce (Lactuca sativa L. cv. Grand Rapids as indicator species. This protocol aims to provide support for the standardization of assays of various chemicals such as allelochemicals and environmental toxicants. The following tests were performed: time of germination, temperature, light, solution volume and Petri dish size. For each test (except for time of germination, the influence of the conditions investigated was determined by the endpoints germination percentage, germination speed index, root length, seedling fresh weight and total dry weight. The results showed that variations in the methods altered the results. It is recommended that bioassays using L. sativa L. cv. Grand Rapids be carried out for a minimum period of four days for assessments of both germination and initial growth and that the experimental conditions include a temperature of 20°C, 90-mm Petri dishes or larger, 0.1 mL cypsela solution, and continuous light or 12-hour photoperiod.

  17. Automated cytochrome c oxidase bioassay developed for ionic liquids' toxicity assessment.

    Science.gov (United States)

    Costa, Susana P F; Martins, Bárbara S F; Pinto, Paula C A G; Saraiva, M Lúcia M F S

    2016-05-15

    A fully automated cytochrome c oxidase assay resorting to sequential injection analysis (SIA) was developed for the first time and implemented to evaluate potential toxic compounds. The bioassay was validated by evaluation of 15 ionic liquids (ILs) with distinct cationic head groups, alkyl side chains and anions. The assay was based on cytochrome c oxidase activity reduction in presence of tested compounds and quantification of inhibitor concentration required to cause 50% of enzyme activity inhibition (EC50). The obtained results demonstrated that enzyme activity was considerably inhibited by BF4 anion and ILs incorporating non-aromatic pyrrolidinium and tetrabutylphosphonium cation cores. Emim [Ac] and chol [Ac], on contrary, presented the higher EC50 values among the ILs tested. The developed automated SIA methodology is a simple and robust high-throughput screening bioassay and exhibited good repeatability in all the tested conditions (rsd<3.7%, n=10). Therefore, it is expected that due to its simplicity and low cost, the developed approach can be used as alternative to traditional screening assays for evaluation of ILs toxicity and identification of possible toxicophore structures. Additionally, the results presented in this study provide further information about ILs toxicity. PMID:26894289

  18. Evaluating the performance of the ORTECR DetectiveTM for emergency urine bioassay

    International Nuclear Information System (INIS)

    The performance of the ORTECR DetectiveTM as a field deployable tool for emergency urine bioassay of 137Cs, 60Co, 192Ir, 169Yb and 75Se was evaluated against ANSI N13.30. The tested activity levels represent 10 % RL (reference level) and 1 % RL defined by [Li C., Vlahovich S., Dai X., Richardson R. B., Daka J. N. and Kramer G. H. Requirements for radiation emergency urine bioassay techniques for the public and first responders. Health Phys (in press, 99(5), 702-707 (2010)]. The tests were conducted for both single radionuclide and mixed radionuclides at two geometries, one conventional geometry (CG) and one improved geometry (IG) which improved the MDAs (minimum detectable amounts) by a factor of 1.6-2.7. The most challenging radionuclide was 169Yb. The measurement of the mixture radionuclides for 169Yb at the CG did not satisfy the ANSI N13.30 requirements even at 10 % RL. At 1 % RL, 169Yb and 192Ir were not detectable at either geometry, while the measurement of 60Co in the mixed radionuclides satisfied the ANSI N13.30 requirements only at the IG. (authors)

  19. Mimicking Daphnia magna bioassay performance by an electronic tongue for urban water quality control

    International Nuclear Information System (INIS)

    Highlights: • -Daphnia magna bioassay can be simulated with multisensor system. • Urban water toxicity can be predicted from potentiometric ET data. • Independent test set validation confirms statistical significance of the results. - Abstract: Toxicity is one of the key parameters of water quality in environmental monitoring. However, being evaluated as a response of living beings (as their mobility, fertility, death rate, etc.) to water quality, toxicity can only be assessed with the help of these living beings. This imposes certain restrictions on toxicity bioassay as an analytical method: biotest organisms must be properly bred, fed and kept under strictly regulated conditions and duration of tests can be quite long (up to several days), thus making the whole procedure the prerogative of the limited number of highly specialized laboratories. This report describes an original application of potentiometric multisensor system (electronic tongue) when the set of electrochemical sensors was calibrated against Daphnia magna death rate in order to perform toxicity assessment of urban waters without immediate involvement of living creatures. PRM (partial robust M) and PLS (projections on latent structures) regression models based on the data from this multisensor system allowed for prediction of toxicity of unknown water samples in terms of biotests but in the fast and simple instrumental way. Typical errors of water toxicity predictions were below 20% in terms of Daphnia death rate which can be considered as a good result taking into account the complexity of the task

  20. Mimicking Daphnia magna bioassay performance by an electronic tongue for urban water quality control

    Energy Technology Data Exchange (ETDEWEB)

    Kirsanov, Dmitry, E-mail: d.kirsanov@gmail.com [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Legin, Evgeny [Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation); Sensor Systems LLC, St. Petersburg (Russian Federation); Zagrebin, Anatoly; Ignatieva, Natalia; Rybakin, Vladimir [Institute of Limnology, Russian Academy of Sciences, St. Petersburg (Russian Federation); Legin, Andrey [Laboratory of Chemical Sensors, St. Petersburg State University, St. Petersburg (Russian Federation); Laboratory of Artificial Sensor Systems, ITMO University, St. Petersburg (Russian Federation)

    2014-05-01

    Highlights: • -Daphnia magna bioassay can be simulated with multisensor system. • Urban water toxicity can be predicted from potentiometric ET data. • Independent test set validation confirms statistical significance of the results. - Abstract: Toxicity is one of the key parameters of water quality in environmental monitoring. However, being evaluated as a response of living beings (as their mobility, fertility, death rate, etc.) to water quality, toxicity can only be assessed with the help of these living beings. This imposes certain restrictions on toxicity bioassay as an analytical method: biotest organisms must be properly bred, fed and kept under strictly regulated conditions and duration of tests can be quite long (up to several days), thus making the whole procedure the prerogative of the limited number of highly specialized laboratories. This report describes an original application of potentiometric multisensor system (electronic tongue) when the set of electrochemical sensors was calibrated against Daphnia magna death rate in order to perform toxicity assessment of urban waters without immediate involvement of living creatures. PRM (partial robust M) and PLS (projections on latent structures) regression models based on the data from this multisensor system allowed for prediction of toxicity of unknown water samples in terms of biotests but in the fast and simple instrumental way. Typical errors of water toxicity predictions were below 20% in terms of Daphnia death rate which can be considered as a good result taking into account the complexity of the task.

  1. Bioassay-Guided Isolation of Two Flavonoids from Derris scandens with Topoisomerase II Poison Activity.

    Science.gov (United States)

    Sangmalee, Suphattra; Laorpaksa, Areerat; Sritularak, Boonchoo; Sukrong, Suchada

    2016-04-01

    Derris scandens (ROXB.) BENTH. (Fabaceae) is used as an alternative treatment for cancer in Thai traditional medicine. Investigation of the topoisomerase II (Top2) poison of compounds isolated from this plant may reveal new drug leads for the treatment of cancer. Bioassay-guided isolation was performed on an extract of D. scandens stems using a yeast cell-based assay. A yeast strain expressing the top2-1 temperature-sensitive mutant was used to assay Top2 activity. At the permissive temperature of 25°C, yeast cells were highly sensitive to Top2 poison agents. At the semi-permissive temperature of 30°C, where enzyme activity was present but greatly diminished, cells displayed only marginal sensitivity. The bioassay-guided fractionation of the extract led to the isolation of two known isoflavones: 5,7,4'-trihydroxy-6,8-diprenylisoflavone (1) and lupalbigenin (2). These two compounds also displayed cytotoxicity against three different cancer cell lines, KB, MCF-7 and NCI-H187. In conclusion, Top2 poison agents from D. scandens are reported for the first time, substantiating the use of D. scandens in Thai traditional medicine for cancer treatment. PMID:26754253

  2. Evaluation and modeling of the parameters affecting fluoride toxicity level in aquatic environments by bioassay method

    Directory of Open Access Journals (Sweden)

    Hamid Reza Shamsollahi

    2014-04-01

    Full Text Available Background: Fluoride exists in various forms in nature and water resources. , The rising level of fluoride in water resources due to discharge of industrial effluents can cause toxicity in aquatic organisms. To prevent toxicity, it is necessary to determine maximum fluoride toxicity as well as effluent discharge limits. The aim of this study was to determine the maximum fluoride toxicity and the factors affecting fluoride toxicity to provide a model in order to determine the effluent discharge limits. Methods: Daphnia magna bioassay in the absence of confounding factors was used to determine the maximum level of fluoride toxicity. Then, bioassay was repeated in the presence of the confounding factors (hardness, temperature and exposure time to determine their effects. Results: In the absence of intervening factors, fluoride LC50 levels determined after 24, 48 and 72 hours exposure were 4.9, 46.5 and 38.7 mg/l, respectively.. Also, the influence of confounding factors on LC50 values was reported significant by Minitab software. Conclusion: Increasing the water hardness reduced fluoride toxicity, and increasing the water temperature and exposure time increased fluoride toxicity in aquatic environments. Therefore, while determining the wastewater discharge limit in terms of fluoride concentration, it is essential to take the effect of confounding factors on fluoride toxicity into account in order to prevent toxicity in the open water resources.

  3. Relative proportions of polycyclic aromatic hydrocarbons differ between accumulation bioassays and chemical methods to predict bioavailability

    International Nuclear Information System (INIS)

    Chemical methods to predict the bioavailable fraction of organic contaminants are usually validated in the literature by comparison with established bioassays. A soil spiked with polycyclic aromatic hydrocarbons (PAHs) was aged over six months and subjected to butanol, cyclodextrin and tenax extractions as well as an exhaustive extraction to determine total PAH concentrations at several time points. Earthworm (Eisenia fetida) and rye grass root (Lolium multiflorum) accumulation bioassays were conducted in parallel. Butanol extractions gave the best relationship with earthworm accumulation (r2 ≤ 0.54, p ≤ 0.01); cyclodextrin, butanol and acetone-hexane extractions all gave good predictions of accumulation in rye grass roots (r2 ≤ 0.86, p ≤ 0.01). However, the profile of the PAHs extracted by the different chemical methods was significantly different (p < 0.01) to that accumulated in the organisms. Biota accumulated a higher proportion of the heavier 4-ringed PAHs. It is concluded that bioaccumulation is a complex process that cannot be predicted by measuring the bioavailable fraction alone. - The ability of chemical methods to predict PAH accumulation in Eisenia fetida and Lolium multiflorum was hindered by the varied metabolic fate of the different PAHs within the organisms.

  4. Dose selection as it pertains to testing a prodrug in carcinogenicity bioassays.

    Science.gov (United States)

    Szczech, G M; Tucker, W E

    1983-01-01

    Toxicologists need more information than is usually available in the early stages of development of a drug in order to choose proper dose levels for testing in the bioassays. The approach most likely to result in successful bioassays involves an early multidisciplinary effort in which there is pharmacokinetic characterization of the test material in both rats and mice. Preliminary 3 month studies are desirable. Periodic sampling of plasma is essential to detect possible non-linear kinetics (as in the example we report herein) reflected as accumulation of the test material or metabolites. This is true regardless of the test substance. However, if one tests prodrugs it may be particularly helpful to know if chemical or enzymatic conversion of the prodrug is linear and if there is reversion to prodrug or other abberant metabolism. Failure to rule out these possibilities could result in subsequent clinically irrelevant organ damage or could compromise longevity or the interpretation of results in lifetime studies. Pharmacokinetic considerations are as valid as the more traditional biologic or morphologic end points used to estimate maximum tolerated or no-effect dose levels. PMID:6681397

  5. DOSEXPRT: A bioassay dosimetry code for Martin Marietta Energy Systems, Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Ward, R.C.; Eckerman, K.F.

    1992-04-01

    The bioassay code DOSEXPRT was developed for Martin Marietta Energy Systems, Inc., to provide compliance with Department of Energy (DOE) Order 5480, Chapter 11. DOSEXPRT computes the intake of a radionuclide in any year (considering both acute and chronic intakes) from in vivo measurements of the retained activity and/or measurements of the activity in excreta. The committed effective and organ doses for the intake are computed as well as the effective and organ doses expected to be received in each calendar year out to 50 years beyond the year of intake. The bioassay records used as input for DOSEXPRT are extracted from the Martin Marietta Energy Systems Occupational Health Information System (OHIS). DOSEXPRT implements a set of algorithms with parameters governing the translocation, retention, and excretion of the nuclide contained in data files specific to the nuclide. These files also contain dose-per-unit-intake coefficients used to compute the committed dose equivalent for the intakes in the year. Annual organ and effective doses are computed using additional dose-rate files that contain data on the dose rate at various times following a unit intake. If measurements are presented for more than one assay for a given nuclide, DOSEXPRT estimates the intake by applying weights assigned in the nuclide file for each assay. DOSEXPRT is accessed off the OHIS MENU No. 4 and designed to be run as a batch processor, but can also be run interactively for testing purposes.

  6. DOSEXPRT: A bioassay dosimetry code for Martin Marietta Energy Systems, Inc

    Energy Technology Data Exchange (ETDEWEB)

    Ward, R.C.; Eckerman, K.F.

    1992-04-01

    The bioassay code DOSEXPRT was developed for Martin Marietta Energy Systems, Inc., to provide compliance with Department of Energy (DOE) Order 5480, Chapter 11. DOSEXPRT computes the intake of a radionuclide in any year (considering both acute and chronic intakes) from in vivo measurements of the retained activity and/or measurements of the activity in excreta. The committed effective and organ doses for the intake are computed as well as the effective and organ doses expected to be received in each calendar year out to 50 years beyond the year of intake. The bioassay records used as input for DOSEXPRT are extracted from the Martin Marietta Energy Systems Occupational Health Information System (OHIS). DOSEXPRT implements a set of algorithms with parameters governing the translocation, retention, and excretion of the nuclide contained in data files specific to the nuclide. These files also contain dose-per-unit-intake coefficients used to compute the committed dose equivalent for the intakes in the year. Annual organ and effective doses are computed using additional dose-rate files that contain data on the dose rate at various times following a unit intake. If measurements are presented for more than one assay for a given nuclide, DOSEXPRT estimates the intake by applying weights assigned in the nuclide file for each assay. DOSEXPRT is accessed off the OHIS MENU No. 4 and designed to be run as a batch processor, but can also be run interactively for testing purposes.

  7. Potential risk of biochar-amended soil to aquatic systems: an evaluation based on aquatic bioassays.

    Science.gov (United States)

    Bastos, A C; Prodana, M; Abrantes, N; Keizer, J J; Soares, A M V M; Loureiro, S

    2014-11-01

    It is vital to address potential risks to aquatic ecosystems exposed to runoff and leachates from biochar-amended soils, before large scale applications can be considered. So far, there are no established approaches for such an assessment. This study used a battery of bioassays and representative aquatic organisms for assessing the acute toxicity of water-extractable fractions of biochar-amended soil, at reported application rates (80 t ha(-1)). Biochar-amended aqueous soil extracts contained cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As) and mercury (Hg) (Σmetals 96.3 µg l(-1)) as well as the 16 priority PAHs defined by the U.S. Environmental Protection Agency (Σ16PAHs 106 ng l(-1)) at contents in the range of current EU regulations for surface waters. Nevertheless, acute exposure to soil-biochar (SB) extracts resulted in species-specific effects and dose-response patterns. While the bioluminescent marine bacterium Vibrio fischeri was the most sensitive organism to aqueous SB extracts, there were no effects on the growth of the microalgae Pseudokirchneriella subcapitata. In contrast, up to 20 and 25% mobility impairment was obtained for the invertebrate Daphnia magna upon exposure to 50 and 100% SB extract concentrations (respectively). Results suggest that a battery of rapid and cost-effective aquatic bioassays that account for ecological representation can complement analytical characterization of biochar-amended soils and risk assessment approaches for surface and groundwater protection. PMID:25213286

  8. Metal toxicity and biodiversity in serpentine soils: application of bioassay tests and microarthropod index.

    Science.gov (United States)

    Visioli, Giovanna; Menta, Cristina; Gardi, Ciro; Conti, Federica Delia

    2013-01-01

    Eco-toxicological or bioassay tests have been intensively discussed as tools for the evaluation of soil quality. Tests using soil organisms, including microarthropods and plants, allow direct estimates to be made of important soil characteristics and functions. In this study we compared the results obtained by two in vitro standard bioassays following ISO or OECD guidelines: (i) the short term-chronic phytotoxicity germination and root elongation test using three different plant species Cucumis sativus L. (Cucurbitaceae), Lepidium sativum L. (Brassicaceae), and Medicago sativa L. (Fabaceae) and (ii) the inhibition of reproduction of Folsomia candida (Collembola) by soil pollutants to investigate the toxicity of a serpentine soil present in the Italian Apennines, rich in heavy metals such as Ni, Cr, and Co. In addition, microarthropod communities were characterised to evaluate the effects of metal contents on the soil fauna in natural conditions. Abundances, Acari/Collembola ratio, biodiversity indices and the QBS-ar index were calculated. Our results demonstrate that the two in vitro tests distinguish differences correlated with metal and organic matter contents in four sub-sites within the serpentinite. Soil fauna characterisation, not previously performed on serpentine soils, revealed differences in the most vulnerable and adapted groups of microarthropods to soil among the four sub-sites: the microarthropod community was found to be rich in term of biodiversity in the sub-site characterised by a lower metal content and a higher organic matter content and vegetation. PMID:23107056

  9. Toxicity of organomercury compounds: Bioassay results as a basis for risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, M. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Chemie; Chau, Y.K. [National Water Research Inst., Burlington, ON (Canada); Dutka, B.J. [National Water Research Inst., Burlington, ON (Canada); McInnis, R. [National Water Research Inst., Burlington, ON (Canada); Kwan, K.K. [National Water Research Inst., Burlington, ON (Canada); Liu, D. [National Water Research Inst., Burlington, ON (Canada)

    1996-12-01

    A former mercury plant, where mercury salts and organomercurials for pesticide use were produced, caused soil contamination in high concentrations. Typical organomercurial products included ethylmercury, phenylmercury, methoxyetylmercury and ethoxyethylmercury, compounds. Risk assessment of these sites must be carried out before any major clean-up processes can be planned. A sensitive speciation technique for the various organomercury species in environmental matrices is a prerequisite for toxicity investigations. In this connection, a high-performance liquid chromatography-atomic fluorescence spectrometry (HPLC-AFS) technique has been developed to differentiate between and determine the presence of eight organomercury compounds in environmental samples. Using this technique, methylmercury, ethylmercury and phenylmercury and some unknown organomercury species were found in soil samples collected from the sites of an old mercury products producing plant. With regard to risk assessment, it is necessary to assess the toxicity of the organomercurials. As different microbial metabolic pathways react differently to mercury and its compounds, batteries of bioassays are, therefore, useful to evaluate the toxicity of pollutants. To describe the toxicity and genotoxicity of MeHg{sup +}, MeOEtHg{sup +}, EtHg{sup +}, EtOEtHg{sup +} and PhHg{sup +}, p-tolymercury chloride, nitromersol and Hg{sup 2+} six bioassays were used: Resazurin reduction method, Spirillum volutans test, nematode toxicity assay Panagrellus redivivus, Toxi-Chromotest and SOS-Chromotest. A ranking of the toxicity of the organomercurial is shown. The SOS-Chromotest indicated genotoxicity for 5-7 organomercurials. (orig.)

  10. Evaluation of the response of Clibanarius africanus (Decapoda: Paguridae to crude oil in static bioassay

    Directory of Open Access Journals (Sweden)

    B.J. Oribhabor

    2012-12-01

    Full Text Available The acute toxicity of Nigeria Bonny light crude oil against hermit crab, Cliabanarius africanus of a tidal creek, Eastern Obolo, Akwa Ibom State, Nigeria was investigated in the laboratory under static bioassay. The test crude oil was found to be poorly toxic to the test organism, resulting in delayed mortality and consequent extension of the bioassay to 8 days. Based on the LC50, the toxicity of the test compound was more manifested on the 8 day than at 96 hour, with a toxicity factor showing that the test compound was approximately 12 times, more manifested against C. africanus on the 8 day than at 96 hour. Paired t-test showed that there was no significant difference between 96h LC50 (549.9 ml l-1 and 8d LC50 (45.2 ml l-1. The results of this study indicated that C. africanus is not a good early warning indicator for oil pollution but its response during spills could serve as a good indicator of adverse impact.

  11. Evaluation of bioassays to monitor surface microlayer toxicity in tropical marine waters.

    Science.gov (United States)

    Rumbold, D G; Snedaker, S C

    1997-02-01

    Bioassays were developed, using embryos of: coral,Montastraea faveolata; graysby, Epinephelus cruentatus;grouper, Epinephelus adscensionis x gruttatus (hybrid); queenconch, Strombus gigas; rock-boring urchin, Echinodermatalucunter; spotted seatrout, Cynoscion nebulosus; variegatedurchin, Lytechinus variegatus; winged pearl oyster, Pteriacolymbus; and yellowtail snapper, Ocyurus chrysurus. Relativesensitivities and precison of various species-endpoint combinations wereevaluated using three reference toxicants: copper, sodium dodecyl sulfate,and Dibrom(R). The 24-h P. colymbus embryo test had the best overallsensitivity and exhibited a high degree of precision. However, oyster embryoswere difficult to obtain and did not aggregate at the air-water interface.Therefore, the P. colymbus embryo test was deemed unsuitable for useas a bioassay for monitoring sea-surface microlayer (SSML) toxicity. Testsbased on normal development of L. variegatus to the early pluteus 3stage and percent normal-live C. nebulosus larvae at 48 h wererelatively sensitive and exhibited good replicability and repeatability. TheL. variegatus urchin embryo test was also found to be highlyreproducible. The results of this comparative study indicated that L.variegatus and C. nebulosus were suitable surrogates forcoral-reef species in toxicity assessments of the SSML. PMID:9069187

  12. Using marine bioassays to classify the toxicity of Dutch harbor sediments.

    Science.gov (United States)

    Stronkhorst, Joost; Schipper, Cor; Brils, Jos; Dubbeldam, Marco; Postma, Jaap; van de Hoeven, Nelly

    2003-07-01

    A procedure was developed to assess contaminated marine sediments from Dutch harbors for possible adverse biological effects using three laboratory bioassays: A 10-d survival test with the amphipod Corophium volutator, a 14-d survival test with the heart urchin Echinocardium cordatum (adults), and the bioluminescence inhibition test with the bacterium Vibrio fischeri (Microtox solid phase test LSP]). Microtox results were mathematically corrected for the modifying influence of fine sediment particles. After a validation procedure on test performance and modifying factors, respectively, 81%, 99%, and 90% of the amphipod, heart urchin, and Microtox results were approved. Lower and upper threshold limits for biological effects were set at respectively 24 and 30% mortality for C. volutator, 27 and 35% mortality for E. cordatum, and 24 and 48 toxic units for the Microtox SP based on significant differences with control sediment and the performance of reference sediments. The bioassays clearly distinguished harbor sediments that give rise to acute effects and those that do not. Threshold limits for the amphipods, heart urchins, and bacteria were exceeded in, respectively, 9 to 17%, 33 to 40%, and 23 to 50% of the sediment samples. Highest effects were observed in sediments from the northerly harbors; there was significantly less response in sediments from the Delta Region and the port of Rotterdam (The Netherlands). The procedure outlined in this paper can be used for routine screening of contaminated dredged material that is proposed for open water disposal. PMID:12836979

  13. Erythropoietin bioassays using fetal mouse liver cells: validations and technical improvements

    International Nuclear Information System (INIS)

    Studies are described which were designed to compare an erythropoietin (Ep) bioassay using the uptake of 125I-deoxyuridine (125-I-UdR) into whole cells cultured in micro-titer plates with an established method where the cells were cultured in 1 ml volumes using the incorporation of 59Fe into heme as the endpoint. The results demonstrate the validity of the substitution of 125I-UdR uptake into whole cells as a replacement for 59Fe incorporation into heme as an assay endpoint and the adaptation of the method to a semi-micro scale with automated cell harvesting. A culture time significantly shorter than 24 h is demonstrated not to be of practical benefit. Two methods are proposed to saturate the growth promoting effects of iron-containing transferrin. The performance of semi-micro, serum-containing bioassay employing untreated serum as the test material is shown to be superior to previous systems for the biological measurement of Ep

  14. Rapid separation of plutonium in bioassay samples using solid extraction chromatography

    International Nuclear Information System (INIS)

    In bioassay monitoring, Pu is chemically separated from the urine matrix by co-precipitation followed by ion exchange technique. In the case of special monitoring, analysis report inputs are required at the earliest. Hence, efforts are being made in Bioassay Laboratory, Trombay to reduce the overall analysis time. The present method requires one complete working day (7-8h) for separation and to reduce it, a procedure was standardized using solid extraction chromatography (TEVAresin, Eichrom Technologies). Further reduction in analysis time was achieved in source preparation for μ-spectrometry by carrying out LaF3 co-precipitation instead of electro-deposition. The present paper reports the method standardized and the average radiochemical yield obtained using TEVA resin and LaF3 micro-precipitation technique. In the present study, a truly rapid method was standardized in the present study which can be applied in routine as well as incident related monitoring of workers. The separation time is reduced by nearly 9-10 times as compared to that required in convention separation using ion exchange technique. The source formed by LaF3 micro-precipitation method though have a poor resolution as compared to those formed by electrodeposition, it is faster, extremely simple and not dependent on pH, current and the applied voltage

  15. Pharmacodynamics of TRPV1 Agonists in a Bioassay Using Human PC-3 Cells

    Directory of Open Access Journals (Sweden)

    Daniel Alvarez-Berdugo

    2014-01-01

    Full Text Available Purpose. TRPV1 is a multimodal channel mainly expressed in sensory neurons. We aimed to explore the pharmacodynamics of the TRPV1 agonists, capsaicin, natural capsaicinoids, and piperine in an in vitro bioassay using human PC-3 cells and to examine desensitization and the effect of the specific antagonist SB366791. Methods. PC-3 cells expressing TRPV1 were incubated with Fluo-4. Fluorescence emission changes following exposition to agonists with and without preincubation with antagonists were assessed and referred to maximal fluorescence following the addition of ionomycin. Concentration-response curves were fitted to the Hill equation. Results. Capsaicin and piperine had similar pharmacodynamics (Emax 204.8 ± 184.3% piperine versus 176.6 ± 35.83% capsaicin, P=0.8814, Hill coefficient 0.70 ± 0.50 piperine versus 1.59 ± 0.86 capsaicin, P=0.3752. In contrast, capsaicinoids had lower Emax (40.99 ± 6.14% capsaicinoids versus 176.6 ± 35.83% capsaicin, P<0.001. All the TRPV1 agonists showed significant desensitization after the second exposition and their effects were strongly inhibited by SB366791. Conclusion. TRPV1 receptor is successfully stimulated by capsaicin, piperine, and natural capsaicinoids. These agonists present desensitization and their effect is significantly reduced by a TRPV1-specific antagonist. In addition, PC-3 cell bioassays proved useful in the study of TRPV1 pharmacodynamics.

  16. Comparative study of Graves' ophthalmopathy by ultrasonography, computed tomography, and fish bioassay

    International Nuclear Information System (INIS)

    In 35 patients with Graves' ophthalmopathy (GO) thyroid function was tested by T3-RIA, T4-RIA, TBI, TRH-test, thyroid scanning, and determination of thyroid autoantibodies. Additional ultrasonography (A-scan), computed tomography (CT) of the orbit, and the determination of an exophthalmogenic serum activity in fish bioassay was performed. Typical alterations for GO were observed in 26 cases with ultrasonography. CT showed an enlargement of medial and/or lateral rectus muscles in 24 of 33 patients, and in 17 cases a region of high density in the apex of the muscle cone. The density of retrobulbar fat after i.v. injection of contrast medium did not differ significantly from that observed in normal men. Characteristic signs of GO were not detected in only 2 cases using both methods together. Exophthalmogenic serum activity was found in the IgG fraction of serum protein. The incidence rate was high (69%), but for diagnostic purpose the fish bioassay cannot be recommended. (orig.) 891 AJ/orig. 892 BRE

  17. Assessment of the environmental quality of coastal sediments by using a combination of in vitro bioassays.

    Science.gov (United States)

    Pérez-Albaladejo, Elisabet; Rizzi, Juliane; Fernandes, Denise; Lille-Langøy, Roger; Karlsen, Odd André; Goksøyr, Anders; Oros, Andra; Spagnoli, Federico; Porte, Cinta

    2016-07-15

    The environmental quality of marine sediments collected in the area of influence of the Po and Danube Rivers was assessed by using a battery of bioassays based on the use of PLHC-1 cells, zebrafish-Pxr-transfected COS-7 cells, and sea bass ovarian subcellular fractions. This allowed the determination of multiple endpoints, namely, cytotoxicity, oxidative stress, induction of CYP1A, activation of zebrafish Pxr and inhibition of ovarian aromatase. Organic extracts of sediments influenced by the Danube River and collected near harbors and urban discharges showed significant cytotoxicity, CYP1A induction and inhibition of aromatase activity. An analogous response of CYP1A induction and zfPxr activation was observed, which suggests the existence of common ligands of AhR and PXR in the sediment extracts. The study highlights the usefulness of the selected bioassays to identify those sediments that could pose a risk to aquatic organisms and that require further action in order to improve their environmental quality. PMID:27207027

  18. Using acute bioassay screens to predict compliance with chronic toxicity permit limits

    International Nuclear Information System (INIS)

    Acute bioassay screens can be cost-effective surrogates for chronic toxicity tests for screening a large number of discharges. Other uses of acute bioassay screens include real time measurement of effluent toxicity and variability, prioritizing discharges for TIE/TRE studies, and evaluating effluent treatability studies. A study was conducted to assess the utility of using 48-hour LC50 data to predict the probability of complying with new chronic toxicity permit limits for produced water discharges from Outer Continental Shelf (OCS) oil and gas platforms in the Gulf of Mexico. Although mysid 48-hour LC50s were correlated with 7-day mysid NOECS, the variability was too great to enable accurate prediction of sub-lethal NOECs based on growth and fecundity. Instead, a decision flowchart was constructed to classify OCS produced water discharges into three categories based on the probability of achieving compliance with future chronic toxicity permit limits. Using toxicity test results from over 50 platforms, the 48-hour LC50 data correctly classified approximately 85% of the discharges. Most importantly, there were no cases where a discharge classified as having a high probability of compliance would have failed its chronic toxicity permit limit. The classification results were used to prioritize platforms for additional toxicity testing and for evaluating improvements to produced water treatment systems

  19. Comparative study of three oligochaete species as indicators of metals in a sediment toxicity bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, K.; Scheuerman, P.; Lanza, G.; Nelson, D. [East Tennessee State Univ., Johnson City, TN (United States); Brinkhurst, R. [Aquatic Resources Center, Franklin, TN (United States)

    1995-12-31

    Three oligochaete species, Tubifex tubifex, Branchiura sowerbyi and Lumbriculus variegatus, were analyzed for bioaccumulation and reproductive effects from reference sediment spiked with Cd or Cu. Sediment was spiked using the Sediment Suspension method to achieve concentrations of 4.0, 8.0 and 16.0 mg Cd/kg sediment (dry weight) and 25.0, 36.0, 50.0, 100.0 mg Cu/kg sediment (dry weight) . The bioassay was conducted under aerated, static conditions for 28 d at 22.5 C. Reproductive effects consisting of number of cocoons and eggs produced a negative linear regression with increasing Cd concentration. Cocoon volume remained consistent. Cu was more toxic to T. tubifex in this bioassay than results reported by the USEPA using similar concentrations. Lower concentrations of Cu also showed a negative linear regression with reproductive effects showing that oligochaetes could be a feasible indicator organism for sediment toxicity in a standardized ecological impact assay using reproduction as an endpoint.

  20. Comparison of various bioassays for dioxins measurements in fuel gas, fly ash and bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    Ota, S.; Kin-ichi, S. [Ministry of the Environment, Tokyo (Japan); Masatoshi, M.; Shin-ichi, S. [National Institute for Environmental Studies, Tsukuba (Japan)

    2004-09-15

    In Japan, the control standards for dioxins (PCDDs, PCDFs and Co-PCBs) in the emission gas, fly and bottom ashes from waste incinerators have been defined in the Law Concerning Special Measures against Dioxins (Dioxins Law). Based on the Dioxins law, an installation personnel of waste incinerators of specified facilities shall measure dioxins in the emission gas and fly and bottom ashes more than once every year followed by reporting the results to their prefectural governor. The present regulating procedure has been set to use high-resolution gas chromatography/ high-resolution mass spectrometry (HRGC/HRMS, hereafter GC/MS) systems to determine dioxin-concentrations. However, the GC/MS measurements are often money- and timeconsuming, since they need complicated steps for sample preparation, expensive equipments and highly skilled technicians. Therefore, it is of high priority to develop rapid and economical alternative methods to measure dioxins. Recently, various assays using biological reactions have drawn a high degree of attention as a candidate for alternative measurement methods of dioxins. During the past decade several studies demonstrated the utility of a chemical (GC/MS) and biological (bioassays/biomarkers) control of waste thermal recycling processes like pyrolysis or incineration treatment. In this paper, we report the results of our recent examinations on the possibility to apply various bioassays to supplementary methods for the present procedure.

  1. Estimation of cytotoxic potency by brine shrimp lethality bioassay application of Clerodendrum infortunatum Linn.

    Institute of Scientific and Technical Information of China (English)

    Talukdar Muhammad Waliullah; Akter MstYeasmin; Ashraful MdAlam; Wahedul Md Islam; Parvez Hassan

    2015-01-01

    Objective: To learn a scientific and systematic knowledge of anticancer, antimicrobial and pharmacological activities of natural products and estimate cytotoxic potency by using ethanol and chloroform extracts of root, leaf and stem of Clerodendrum infortunatum (Verbenaceae) due to its random use in customary and traditional medicine to cure common ailments such as intestinal disorder, diarrhea, tuberculosis and respiratory problems etc. Methods: The in vitro application was carried out with the bench-top bioassay method by using brine shrimp lethality bioassay. Results: All of the crude extracts were found to be lethal and effective. The LC50 value of ethyl alcohol fraction of root was 20.845 mg/L compared to the standard drug tetracycline of 14.675 mg/L to brine shrimp nauplii, indicating that the extracts were biologically active. Conclusions: The cytotoxic study of LC50 value showed that a good correlation with the antibiotic tetracycline. From the comparative correlation error bars and percentage, we understood that ethyl alcohol fraction of root extract was very effective. This study serves as a basis for further research to lead compounds to be isolated so that it may be as a template for the implications of these results for bioactivity and drug discovery potential of herbal products.

  2. Antimicrobial Activity and Brine Shrimp Lethality Bioassay of the Leaves Extract of Dillenia indica Linn.

    Science.gov (United States)

    Apu, As; Muhit, Ma; Tareq, Sm; Pathan, Ah; Jamaluddin, Atm; Ahmed, M

    2010-01-01

    The crude methanolic extract of Dillenia indica Linn. (Dilleniaceae) leaves has been investigated for the evaluation of antimicrobial and cytotoxic activities. Organic solvent (n-hexane, carbon tetrachloride and chloroform) fractions of methanolic extract and methanolic fraction (aqueous) were screened for their antimicrobial activity by disc diffusion method. Besides, the fractions were screened for cytotoxic activity using brine shrimp (Artemia salina) lethality bioassay. Among the four fractions tested, n-hexane, carbon tetrachloride, and chloroform fractions showed moderate antibacterial and antifungal activity compared to standard antibiotic, kanamycin. The average zone of inhibition was ranged from 6 to 8 mm at a concentration of 400 µg/disc. But the aqueous fraction was found to be insensitive to microbial growth. Compared to vincristine sulfate (with LC(50) of 0.52 µg/ ml), n-hexane and chloroform fractions demonstrated a significant cytotoxic activity (having LC(50) of 1.94 µg/ml and 2.13 µg/ml, respectively). The LC(50) values of the carbon tetrachloride and aqueous fraction were 4.46 µg/ml and 5.13 µg/ ml, respectively. The study confirms the moderate antimicrobial and potent cytotoxic activities of Dillenia indica leaves extract and therefore demands the isolation of active principles and thorough bioassay. PMID:21331191

  3. Bioassay and characterization of soil microorganisms involved in the biodegradation of the fungicide, metalaxyl

    International Nuclear Information System (INIS)

    A sensitive bioassay was developed to detect low concentrations of metalaxyl in soils. The quantitative estimation of metalaxyl in soils was based on a significant positive relationship between the radial growth of Phytophthora boehmeriae and the log concentration of the fungicide in the agar. The isolate of P. boehmeriae was chosen for its sensitivity to metalaxyl as manifested in a linear growth response on cornmeal agar over a range of 2 to 30 ng/ml. The sensitivity and quantitative nature of the bioassay was confirmed by comparison with data obtained by using 14C-metalaxyl. Metabolism of metalaxyl was detected in three of five avocado soils that had repeated applications of the fungicide over 2-5 yr. The average disappearance of metalaxyl was 28 days, and in the most active soils was 14 days. The composition and level of the microbial populations of soils, either active or inactive in the breakdown of metalaxyl, did not differ. Fungal and bacterial microflora recovered from these two soils by use of either selective media or filtration techniques were capable of metabolizing metalaxyl over a 45-day period

  4. Intemational collaborative study on the preparation of 1st international standard for rhTSH for bioassay

    International Nuclear Information System (INIS)

    The history of the international collaborative studies on the preparation of standards of TSH for bioassay and immunoassay was reviewed. The result of collaborative study on the 1st international standard for thyroid-stimulating hormone, recombinant, human, for bioassay was reported in detail in this article. Based on the results of this collaborative study, it is proposed that the candidate standard be established as the international standard for rhTSH for bioassay, and be assigned an activity of 9.5 IU per ampoule. The national standard preparation of TSH for immunoassay was also reassayed, revealing the potency to be 0.557 mIU/ampoule, i.e. 92. 8% of the labelled value of 0.600mIU/ampoule, a reasonable consistency. (authors)

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

    Science.gov (United States)

    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. PMID:26590191

  6. In vivo genotoxicity of furan in F344 rats at cancer bioassay doses

    International Nuclear Information System (INIS)

    Furan, a potent rodent liver carcinogen, is found in many cooked food items and thus represents a human cancer risk. Mechanisms for furan carcinogenicity were investigated in male F344 rats using the in vivo Comet and micronucleus assays, combined with analysis of histopathological and gene expression changes. In addition, formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III (EndoIII)-sensitive DNA damage was monitored as a measure of oxidative DNA damage. Rats were treated by gavage on four consecutive days with 2, 4, and 8 mg/kg bw furan, doses that were tumorigenic in 2-year cancer bioassays, and with two higher doses, 12 and 16 mg/kg. Rats were killed 3 h after the last dose, a time established as producing maximum levels of DNA damage in livers of furan-treated rats. Liver Comet assays indicated that both DNA strand breaks and oxidized purines and pyrimidines increased in a near-linear dose-responsive fashion, with statistically significant increases detected at cancer bioassay doses. No DNA damage was detected in bone marrow, a non-target tissue for cancer, and peripheral blood micronucleus assays were negative. Histopathological evaluation of liver from furan-exposed animals produced evidence of inflammation, single-cell necrosis, apoptosis, and cell proliferation. In addition, genes related to apoptosis, cell-cycle checkpoints, and DNA-repair were expressed at a slightly lower level in the furan-treated livers. Although a mixed mode of action involving direct DNA binding cannot be ruled out, the data suggest that furan induces cancer in rat livers mainly through a secondary genotoxic mechanism involving oxidative stress, accompanied by inflammation, cell proliferation, and toxicity. -- Highlights: ► Furan is a potent rodent liver carcinogen and represents a human cancer risk. ► Furan induces DNA damage in rat liver at cancer bioassay doses. ► Furan induces oxidative stress, inflammation and cell proliferation in rat liver. ► Expression of

  7. In vivo genotoxicity of furan in F344 rats at cancer bioassay doses

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Wei, E-mail: Wei.Ding@fda.hhs.gov [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Petibone, Dayton M. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Latendresse, John R. [Toxicologic Pathology Associates, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Pearce, Mason G. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Muskhelishvili, Levan; White, Gene A. [Toxicologic Pathology Associates, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Chang, Ching-Wei [Division of Personalized Nutrition and Medicine, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Mittelstaedt, Roberta A.; Shaddock, Joseph G.; McDaniel, Lea P. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Doerge, Daniel R. [Division of Biochemical Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Morris, Suzanne M.; Bishop, Michelle E.; Manjanatha, Mugimane G.; Aidoo, Anane; Heflich, Robert H. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States)

    2012-06-01

    Furan, a potent rodent liver carcinogen, is found in many cooked food items and thus represents a human cancer risk. Mechanisms for furan carcinogenicity were investigated in male F344 rats using the in vivo Comet and micronucleus assays, combined with analysis of histopathological and gene expression changes. In addition, formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III (EndoIII)-sensitive DNA damage was monitored as a measure of oxidative DNA damage. Rats were treated by gavage on four consecutive days with 2, 4, and 8 mg/kg bw furan, doses that were tumorigenic in 2-year cancer bioassays, and with two higher doses, 12 and 16 mg/kg. Rats were killed 3 h after the last dose, a time established as producing maximum levels of DNA damage in livers of furan-treated rats. Liver Comet assays indicated that both DNA strand breaks and oxidized purines and pyrimidines increased in a near-linear dose-responsive fashion, with statistically significant increases detected at cancer bioassay doses. No DNA damage was detected in bone marrow, a non-target tissue for cancer, and peripheral blood micronucleus assays were negative. Histopathological evaluation of liver from furan-exposed animals produced evidence of inflammation, single-cell necrosis, apoptosis, and cell proliferation. In addition, genes related to apoptosis, cell-cycle checkpoints, and DNA-repair were expressed at a slightly lower level in the furan-treated livers. Although a mixed mode of action involving direct DNA binding cannot be ruled out, the data suggest that furan induces cancer in rat livers mainly through a secondary genotoxic mechanism involving oxidative stress, accompanied by inflammation, cell proliferation, and toxicity. -- Highlights: ► Furan is a potent rodent liver carcinogen and represents a human cancer risk. ► Furan induces DNA damage in rat liver at cancer bioassay doses. ► Furan induces oxidative stress, inflammation and cell proliferation in rat liver. ► Expression of

  8. Use of viral promoters in mammalian cell-based bioassays: How reliable?

    Directory of Open Access Journals (Sweden)

    Gill-Sharma Manjit

    2004-01-01

    Full Text Available Abstract Cell-based bioassays have been suggested for screening of hormones and drug bioactivities. They are a plausible alternative to animal based methods. The technique used is called receptor/reporter system. Receptor/reporter system was initially developed as a research technique to understand gene function. Often reporter constructs containing viral promoters were used because they could be expressed with very 'high' magnitude in a variety of cell types in the laboratory. On the other hand mammalian genes are expressed in a cell/tissue specific manner, which makes them (i.e. cells/tissues specialized for specific function in vivo. Therefore, if the receptor/reporter system is to be used as a cell-based screen for testing of hormones and drugs for human therapy then the choice of cell line as well as the promoter in the reporter module is of prime importance so as to get a realistic measure of the bioactivities of 'test' compounds. We evaluated two conventionally used viral promoters and a natural mammalian promoter, regulated by steroid hormone progesterone, in a cell-based receptor/reporter system. The promoters were spliced into vectors expressing enzyme CAT (chloramphenicol acetyl transferase, which served as a reporter of their magnitudes and consistencies in controlling gene expressions. They were introduced into breast cell lines T47D and MCF-7, which served as a cell-based source of progesterone receptors. The yardstick of their reliability was highest magnitude as well as consistency in CAT expression on induction by sequential doses of progesterone. All the promoters responded to induction by progesterone doses ranging from 10-12 to 10-6 molar by expressing CAT enzyme, albeit with varying magnitudes and consistencies. The natural mammalian promoter showed the most coherence in magnitude as well as dose dependent expression profile in both the cell lines. Our study casts doubts on use of viral promoters in a cell-based bioassay for

  9. [Bioassay on oviposition repellency of non-preferable plant extracts against citrus red mite Panonychus citri].

    Science.gov (United States)

    Cen, Yijing; Pang, Xiongfei; Zhou, Qiong; Peng, Yuefeng; Xu, Changbao

    2004-09-01

    The oviposition repellency of the alcohol extracts from 50 species of non-preferable plants and azadirachtin against citrus red mite (Panonychus citri) was determined using laboratory bioassays. In choice tests, the extracts from 42 of the 50 plant species and 1% azadirachtin (2000 x) significantly reduced oviposition 1d after treatment. The repellency effect of the extracts from the 42 plant species was better than that of azadirachtin. Mikania micrantha extract had the best result, with an Interference Index of Population Control (IIPC) of 0.087 1 d after treatment, and significantly reduced oviposition for 9 d, while the extracts from Sesbania cannabina, Allium tuberosum, Paederia scandens, Duranta erecta and Dicranopteris pedata also had good effects, with an oviposition repellency of over 70% 1 d after treatment, and significantly reduced oviposition for 4-6 d. The effect became weaker as time went on. None of the extracts showed significant oviposition attraction. PMID:15669510

  10. Theobroma cacao: Review of the Extraction, Isolation, and Bioassay of Its Potential Anti-cancer Compounds.

    Science.gov (United States)

    Baharum, Zainal; Akim, Abdah Md; Hin, Taufiq Yap Yun; Hamid, Roslida Abdul; Kasran, Rosmin

    2016-02-01

    Plants have been a good source of therapeutic agents for thousands of years; an impressive number of modern drugs used for treating human diseases are derived from natural sources. The Theobroma cacao tree, or cocoa, has recently garnered increasing attention and become the subject of research due to its antioxidant properties, which are related to potential anti-cancer effects. In the past few years, identifying and developing active compounds or extracts from the cocoa bean that might exert anti-cancer effects have become an important area of health- and biomedicine-related research. This review provides an updated overview of T. cacao in terms of its potential anti-cancer compounds and their extraction, in vitro bioassay, purification, and identification. This article also discusses the advantages and disadvantages of the techniques described and reviews the processes for future perspectives of analytical methods from the viewpoint of anti-cancer compound discovery. PMID:27019680

  11. Rapid Bioassay-Guided Isolation of Antibacterial Clerodane Type Diterpenoid from Dodonaea viscosa (L. Jaeq.

    Directory of Open Access Journals (Sweden)

    Muhammad Khurram

    2015-08-01

    Full Text Available Plant extracts are complex matrices and, although crude extracts are widely in use, purified compounds are pivotal in drug discovery. This study describes the application of automated preparative-HPLC combined with a rapid off-line bacterial bioassay, using reduction of a tetrazolium salt as an indicator of bacterial metabolism. This approach enabled the identification of fractions from Dodonaea viscosa that were active against Staphylococcus aureus and Escherichia coli, which, ultimately, resulted in the identification of a clerodane type diterpenoid, 6β-hydroxy-15,16-epoxy-5β, 8β, 9β, 10α-cleroda-3, 13(16, 14-trien-18-oic acid, showing bacteriostatic activity (minimum inhibitory concentration (MIC = 64–128 µg/mL against test bacteria. To the best of our knowledge, this is the first report on antibacterial activity of this metabolite from D. viscosa.

  12. Monitoring North Sea oil production discharges using passive sampling devices coupled with in vitro bioassay techniques.

    Science.gov (United States)

    Harman, Christopher; Farmen, Eivind; Tollefsen, Knut Erik

    2010-09-01

    Semipermeable membrane devices (SPMDs) and polar organic integrative chemical samplers (POCIS) were deployed in vicinity of an offshore oil production platform discharging production water (produced water) to the North Sea. Extracts from SPMDs and POCIS were subjected to chemical analysis for polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APs) respectively, and also assessed for acute toxicity (cytotoxicity), estrogen receptor (ER)-mediated production of vitellogenin (Vtg) and induction of 7-ethoxyresorufin-O-deethylase (EROD) activity in primary hepatocytes from rainbow trout (Oncorhynchus mykiss). Chemical analysis of the extracts revealed a gradient of exposure away from the platform for low molecular weight PAH and AP, whereas no exposure gradient was apparent for high molecular weight PAH, as expected. These data coupled with earlier work allowed a tentative general exposure scenario to be determined. The passive sampler extracts also caused modulation of the bioassay toxicity endpoints, although a clear gradient of response relative to the discharge point could not be identified. PMID:20683536

  13. Rapid, Bioassay-Guided Process for the Detection and Identification of Antibacterial Neem Oil Compounds.

    Science.gov (United States)

    Krüzselyi, Dániel; Nagy, Róbert; Ott, Péter G; Móricz, Ágnes M

    2016-08-01

    Bioassay guidance was used along the whole process including method development, isolation and identification of antibacterial neem (Azadirachta indica) oil compounds. The biomonitoring was performed by direct bioautography (DB), a combination of thin-layer chromatography (TLC) and antimicrobial detection. DB of neem oil showed one antibacterial zone that was not UV-active; therefore, the TLC separation was improved under DB control. The chromatographic zone that exhibited activity against Bacillus subtilis, Xanthomonas euvesicatoria, Aliivibrio fischeri, Staphylococcus aureus and methicillin-resistant Staphylococcus aureus was characterized by TLC reagents, indicating a lipophilic, fatty acid-like chemical feature. Two compounds were found and identified in the active zone by high-performance liquid chromatography-electrospray ionization mass spectrometry as linoleic and oleic acids. Both fatty acids inhibited B. subtilis, but A. fischeri was sensitive only against linoleic acid. PMID:26951543

  14. Evaluation of oxidation techniques for preparing bioassay and environmental samples for liquid scintillation counting

    International Nuclear Information System (INIS)

    In environmental and biological monitoring for carbon-14 and tritium, the presence of color and chemical quenching agents in the samples can degrade the efficiency of liquid scintillation counting. A series of experiments was performed to evaluate the usefulness, under routine conditions, of first oxidizing the samples to improve the counting by removing the color and quenching agents. The scintillation counter was calibrated for the effects of quenching agents on its counting efficiency. Oxidizing apparatus was tested for its ability to accurately recover the 14C and 3H in the samples. Scintillation counting efficiences were compared for a variety of oxidized and unoxidized environmental and bioassay samples. The overall conclusion was that, for routine counting, oxidation of such samples is advantageous when they are highly quenched or in solid form

  15. Occupational program monitoring in Uranium Concentrate Unity at Caetite (URA) - Bahia State, Brazil: bioassay program

    International Nuclear Information System (INIS)

    The principal aim of bioassay monitoring program in Uranium Concentrate Unity, URA, in Caetite is the maintenance of acceptably safe and satisfactory working conditions, according to national and international norms. Specifically, the objective is to interpret measurements in terms of intake of uranium and committed effective dose, so that the results can be used to demonstrate compliance with the system of dose limitation and, mainly, the optimization of radiation protection. The employed technique is the measurement of uranium in excreta from workers in mine, crushing and uranium concentrate production areas. In conclusion, workers from mining and crushing areas should be monitored by the routine program; urine and feces samples should be analyzed by mass spectrometry, with ICP-MS. The operational monitoring program should be carried out in workers from uranium concentrate production area; urine and feces samples should be analyzed by less expensive techniques. (author)

  16. High-throughput tri-colour flow cytometry technique to assess Plasmodium falciparum parasitaemia in bioassays

    DEFF Research Database (Denmark)

    Tiendrebeogo, Regis W; Adu, Bright; Singh, Susheel K;

    2014-01-01

    BACKGROUND: Unbiased flow cytometry-based methods have become the technique of choice in many laboratories for high-throughput, accurate assessments of malaria parasites in bioassays. A method to quantify live parasites based on mitotracker red CMXRos was recently described but consistent...... distinction of early ring stages of Plasmodium falciparum from uninfected red blood cells (uRBC) remains a challenge. METHODS: Here, a high-throughput, three-parameter (tri-colour) flow cytometry technique based on mitotracker red dye, the nucleic acid dye coriphosphine O (CPO) and the leucocyte marker CD45......-colour technique is rapid, cost effective and robust with comparable sensitivity to microscopy and capable of discriminating between live and dead and/or compromised parasites. Staining for CD45 improved parasitaemia estimates in ADCI assay since high numbers of leucocytes interfered with the accurate...

  17. Bioassay-guided isolation of prenylated xanthones and polycyclic acylphloroglucinols from the leaves of Garcinia nujiangensis.

    Science.gov (United States)

    Xia, Zheng-Xiang; Zhang, Dan-Dan; Liang, Shuang; Lao, Yuan-Zhi; Zhang, Hong; Tan, Hong-Sheng; Chen, Shi-Lin; Wang, Xin-Hong; Xu, Hong-Xi

    2012-08-24

    Bioassay-guided fractionation of the acetone extract of the leaves of Garcinia nujiangensis resulted in the isolation of two new prenylated xanthones, nujiangexanthones A (1) and B (2), three new polycyclic polyprenylated acylphloroglucinols, nujiangefolins A-C (3-5), and 10 known related analogues. The structures of compounds 1-5 were elucidated by interpretation of their spectroscopic data. Compounds 3 and 4 are unusual polycyclic polyprenylated acylphloroglucinols in which the enol hydroxy group forms a six-membered ring with a benzene ring carbon. The compounds isolated were evaluated for their cytotoxic effects against 11 cancer cell lines and immortalized MIHA normal liver cells, and the test substances demonstrated selectivity toward the cancer cells. Isojacareubin (6) was found to be the most potent cytotoxic compound of those tested. PMID:22871217

  18. Bioassay-guided isolation of xanthones and polycyclic prenylated acylphloroglucinols from Garcinia oblongifolia.

    Science.gov (United States)

    Huang, Sheng-Xiong; Feng, Chao; Zhou, Yan; Xu, Gang; Han, Quan-Bin; Qiao, Chun-Feng; Chang, Donald C; Luo, Kathy Qian; Xu, Hong-Xi

    2009-01-01

    Bioassay-guided fractionation of the acetone extract of the bark of Garcinia oblongifolia has resulted in the isolation of three new xanthones, oblongixanthones A-C (1-3), three new polyprenylated benzoylphloroglucinols, oblongifolins E-G (4-6), and 12 known compounds. Oblongifolins I (5) and J (6) are the first natural products that have similar structural features to those of two known oxidation products of garcinol. The structures of the new compounds 1-6 were characterized by spectroscopic data interpretation. All isolates were assayed for their apoptosis-inducing effects against HeLa-C3 cells. Oblongifolin C (16) was found to be the most potent apoptotic inducer of the compounds evaluated. PMID:19113969

  19. Effect of external agent on chemiluminescence in bioassay sample - a study

    International Nuclear Information System (INIS)

    Tritium is one of the important radio nuclide contributing about 30-35% of collective dose through internal exposure of plant personnel in Indian PHWRs. Internal dose is monitored by bioassay using liquid scintillation analyzer. There are some external agents that interfere with the tritium counting in urine sample of individuals. These external agents give rise to chemiluminescence in the sample, which may result in wrong interpretation of the counting rates. One such case was studied at Rajasthan Atomic Power Station (RAPS)-3 and 4 in which urine sample of an individual indicated significantly high uptake of tritium whereas the person was not involved in any radioactive job. Investigation revealed that counts due to the sample were caused by chemiluminescence in the urine sample because of homeopathic drug, which the person was taking. (author)

  20. CYTOTOXIC (BRINE SHRIMP LETHALITY BIOASSAY AND ANTIOXIDANT INVESTIGATION OF BARRINGTONIA ACUTANGULA (L.”

    Directory of Open Access Journals (Sweden)

    Md. Asaduzzaman

    2015-08-01

    Full Text Available Barringtonia acutangula (L. gaertn. (Family: Barringtoniaceae, a medicinal small to medium evergreen tree known as ‘Hijal’, is used in diarrhoea, dysentery, colic, flatulence, cooling, aperients expectorant, stimulating emetic, astringents to the bowel, antihelminthic, bronchitis, lumber pain, hallucinations, seminal weakness, gonorrhoea and many other ailments in rural areas of Bangladesh It is also used as traditional medicine in other countries. But till to date, sporadic attempts have been made for the scientific and methodical validation of these traditional claims. In Brine Shrimp Lethality Bioassay, all the extracts produced dose dependent cytotoxicity effect to brine shrimp nauplii with methanol extract of leaf exhibiting highest toxicity having LC50 value 46.24 μg/ml where standard vincristine sulphate had the LC50 value of 0.69 μg/ml. & In antioxidant attempt by reducing power and CUPRAC assays, pet. ether extract of leaf were found to exhibit moderate but concentration dependent reducing power respectively.

  1. Methotrexate intercalated layered double hydroxides with the mediation of surfactants: Mechanism exploration and bioassay study.

    Science.gov (United States)

    Dai, Chao-Fan; Tian, De-Ying; Li, Shu-Ping; Li, Xiao-Dong

    2015-12-01

    Methotrexatum intercalated layered double hydroxides (MTX/LDHs) hybrids were synthesized by the co-precipitation method and three kinds of nonionic surfactants with different hydrocarbon chain lengths were used. The resulting hybrids were then characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). XRD and FTIR investigations manifest the successful intercalation of MTX anions into the interlayer of LDHs. TEM graphs indicate that the morphology of the hybrids changes with the variation of the chain length of the surfactants, i.e., the particles synthesized using polyethylene glycol (PEG-7) present regular disc morphology with good monodispersity, while samples with the mediation of alkyl polyglycoside (APG-14) are heavily aggregated and samples with the addition of polyvinylpyrrolidone (PVP-10) exhibit irregular branches. Furthermore, the release and bioassay experiments show that monodisperse MTX/LDHs present good controlled-release and are more efficient in the suppression of the tumor cells. PMID:26354264

  2. Laboratory bioassays of entomopathogenic fungi for control of Delia radicum (L.) larvae.

    Science.gov (United States)

    Bruck, Denny J; Snelling, Jane E; Dreves, Amy J; Jaronski, Stefan T

    2005-06-01

    Laboratory soil bioassays were performed at economic field rates for in-furrow (3.85 x 10(6)spores/g dry soil) and broadcast (3.85 x 10(5)spores/g dry soil) applications with three isolates of Metarhizium anisopliae (F52, ATCC62176, and ARSEF5520) and one isolate of Beauveria bassiana (GHA). All isolates tested were infective to second instar Delia radicum (L.). The conditionally registered M. anisopliae isolate (F52) performed best killing an average of 85 and 72% of D. radicum larvae at the high and low concentration, respectively. The mean LC50 and LC95 of F52 against second instar D. radicum was 2.7 x 10(6) and 1.8 x 10(8)spores/g dry soil, respectively. The use of F52 in an integrated management program is discussed. PMID:16087004

  3. Use of a cytochemical bioassay for determination of thyroid stimulating hormone (TSH) in clinical investigation

    International Nuclear Information System (INIS)

    Recently a highly sensitive cytochemical bioassay (CBA) for the determination of human TSH has been developed. We could show that this assay is specific for TSH and measurements done on plasma of normal euthyroid persons agree well with radioimmunological findings. Due to the extreme sensitivity of the CBA we were able to detect low but measurable TSH levels in patients with primary hyperthyroidism, which were not increased by TRH treatment before therapeutic treatment. After therapeutic treatment, TRH application was able to stimulate additional biologically active TSH release which, however, barely reached the lowest limit of detection by RIA. In certain pathological cases we were able to detect elevated plasma TSH levels, which were active immunologically but inactive biologically. (orig.)

  4. Isolation of bioactive allelochemicals from sunflower (variety Suncross-42) through fractionation-guided bioassays.

    Science.gov (United States)

    Anjum, Tehmina; Bajwa, Rukhsana

    2010-11-01

    Plants are rich source of biologically active allelochemicals. However, natural product discovery is not an easy task. Many problems encountered during this laborious practice can be overcome through the modification of preliminary trials. Bioassay-directed isolation of active plant compounds can increase efficiency by eliminating many of the problems encountered. This strategy avoids unnecessary compounds, concentrating on potential components and thus reducing the cost and time required. In this study, a crude aqueous extract of sunflower leaves was fractionated through high performance liquid chromatography. The isolated fractions were checked against Chenopodium album and Rumex dentatus. The fraction found active against two selected weeds was re-fractionated, and the active components were checked for their composition. Thin layer chromatography isolated a range of phenolics, whereas the presence of bioactive terpenoids was confirmed through mass spectroscopy and nuclear magnetic resonance spectroscopy. PMID:20981619

  5. ICP-MS: Answer to Challenges of Bioassay Monitoring of Occupationally Workers for Thorium and Uranium

    International Nuclear Information System (INIS)

    The application of bioassay monitoring to assess the internal radiation dose to subjects exposed to elevated levels of thorium (Th), uranium (U) and their related compounds from the working environment require the precise measurement of the annual increments of daily urinary excretion over and above the previous year's excretion rate. At GSF Research Center for Environment and Health (Germany), a highly sensitive and precise analytical method was developed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to measure extremely low concentrations of Th and U in urine. Using this method, the minimum limits of determination (LOD) of 1 ng/L for both radionuclides could be achieved. At the concentration range between 15-25 ng/L, the precision is better that 10%. The details of the method and its applications are discussed here. (Author) 3 refs

  6. Ecotoxicological assessment of metal-polluted urban soils using bioassays with three soil invertebrates.

    Science.gov (United States)

    Santorufo, Lucia; Van Gestel, Cornelis A M; Maisto, Giulia

    2012-07-01

    This study aimed at assessing the quality of urban soils by integrating chemical and ecotoxicological approaches. Soils from five sites in downtown Naples, Italy, were sampled and characterized for physical-chemical properties and total and water-extractable metal concentrations. Bioassays with Eisenia andrei, Enchytraeus crypticus and Folsomia candida were performed to assess toxicity of the soils, using survival, reproduction and growth as the endpoints. Metal bioaccumulation in the animals was also measured. The properties and metal concentrations of the soils strongly differed. Metal bioaccumulation was related with total metal concentrations in soil and was highest in E. crypticus, which was more sensitive than E. andrei and F. candida. Responses of the three species to the investigated soils seemed due to both metal contamination and soil properties. PMID:22445389

  7. Critical parameters in the MCF-7 cell proliferation bioassay (E-Screen)

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Høj; Nielsen, Jesper Bo

    2002-01-01

    The MCF-7 cell proliferation bioassay has grown in popularity as a rapid test for detecting potentially oestrogenic compounds. Several MCF-7 cell sublines with different sensitivities to oestrogens are currently used, with maximal proliferation responses ranging from two- to 10-fold above those of...... hormone-free controls. In the highly responsive MCF-7 BUS cell line, we evaluated critical assay parameters for test performance, including growth conditions, initial seeding densities and differences in growth stimulation in medium containing human serum or fetal calf serum as well as appropriate...... solvents for oestrogen-mimicking compounds. Modifications significantly reduced the labour-intensive steps and overall assay costs without affecting the sensitivity of the assay. Using this optimized test regimen, the responsiveness of treated MCF-7 BUS cells was consistently increased up to 11-fold over...

  8. Bio-assay Guided Isolation of Anti-cancer Compounds from Anthocephalus cadamba Bark.

    Science.gov (United States)

    Kumar, Deepak; Tejaswi, Chilukuri; Rasamalla, Saiprasanna; Mallick, Sumana; Pala, Bikas C

    2015-08-01

    Anthocephalus cadamba, an important plant in the traditional system of medicine in India, is reported to possess anticancer activity. Guided by bio-assay tests using human colorectal (HCT116) and hepatocellular carcinoma (HepG2) cell lines, it has been shown to contain three active constituents, the triterpenoid saponins 3-O-[α-L-rhamnopyranosyl]-quinovic acid (1) and 3-O-[α-L-rhamnopyranosyl]-quinovic acid 28-O-[β-D-glucopyranosyl] ester (2), and the alkaloid cadambine (3). The structures of the isolated compounds were established using spectroscopic techniques. The isolated compounds demonstrated concentration dependent inhibition of both the cell lines, where compound 3 proved to be the most potent inhibitor of cell line HCT116 (IC50 45 +/- 4 μg/mL) and compound 2 demonstrated maximum inhibitory activity against HepG2 cell line with an IC50 value of 89 +/- 7 μg/mL. PMID:26434112

  9. Robust Discrimination between Single Gold Nanoparticles and Their Dimers in Aqueous Solution for Ultrasensitive Homogeneous Bioassays

    Directory of Open Access Journals (Sweden)

    Jun Kobayashi

    2015-01-01

    Full Text Available We propose a robust method to distinguish isolated single gold nanoparticles (AuNP monomers and their dimers under Brownian motion, a key for ultrasensitive homogeneous bioassays, including AuNP sandwich assays. To detect dimers and distinguish them from a larger number of monomers in aqueous solution, single-particle polarization microscopy was performed. For the accurate detection of individual particles, the optical anisotropy and rotational diffusion time are measured because a dimer is much more anisotropic than the nearly spherical monomer and the rotational diffusion time of a dimer is four times that of a monomer. By employing an autocorrelation analysis, we defined a measure of distinguishing that simultaneously enables high detection probability and low error probability. The detection platform offers homogeneous DNA hybridization assays and immunoassays at the subpicomolar level.

  10. A Bioassay Technique to Study Clomazone Residues in Sandy Loam Soil

    Directory of Open Access Journals (Sweden)

    Jelena Gajić Umiljendić

    2013-01-01

    Full Text Available A bioassay test was conducted to evaluate the sensitivity of maize, sunflower and barley toclomazone residues in sandy loam soil. Clomazone was applied at different rates from 0.12 to12 mg a.i./kg of soil. The parameters measured 14 days after treatment were: shoot height, freshand dry weight, and content of pigments (carotenoids, chlorophyll a and chlorophyll b. Theresults showed that the lowest clomazone concentration caused a significant reduction in allmeasured parameters for barley and sunflower shoots. Fresh weight of maize shoots was notsensitive to clomazone residual activity in soil while the other parameters were highly inhibited.Nomenclature: clomazone (2-(2-chlorbenzyl-4,4-dimethyl-1,2-oxazolidin-3-one, maize(Zea mays L., sunflower (Helianthus annuus L., barley (Hordeum vulgare L.

  11. Symposium on Short-Term Genetic Bioassays in the Evaluation of Complex Environmental Mixtures

    CERN Document Server

    Sandhu, Shahbeg; Lewtas, Joellen; Claxton, Larry; Strauss, Gary; Nesnow, Stephen

    1985-01-01

    With this proceedings of the fourth symposium on complex mixtures, we continue to revise and extend our knowledge of genetic methods for the evaluation of chemical mixtures in the environment. The early chapters of this volume are devoted to new bioassay techniques that are directly applicable to the monitoring of environments contaminated with genotoxic chemicals. Microbiological methods have been further refined to meet the special needs of atmospheric monitoring so that very small samples may now be efficiently tested. New in situ methods utilizing green plants actually avoid many of the usual difficulties of sample collection and preparation and offer special advantages in monitoring wastewater, sludges, and hazardous wastes. Insects also are being employed very effectively in the evaluation of gaseous air pollutants in controlled laboratory investigations. Increased emphasis has been placed on a comprehensive assessment of the potential of complex mixtures t9 cause various kinds of genetic damage. New as...

  12. Acute toxicity bioassay with native plants to evaluate an oil spill

    Directory of Open Access Journals (Sweden)

    Vivien Pentreath

    2015-06-01

    Full Text Available Plant bioassays are excellent tools for the evaluation of environmental risks. In particular the use of seeds of vascular plants is recommended due to their higher sensitivity. The aim of this study was to evaluate the behavior of native plants in order for them to be used as biological indicators of environmental oil pollution in relation to a standardized bioindicator. We analyzed the germination index (GI of Lactuca sativa L., Atriplex lampa (Moq. D.Dietri. and Prosopis denudans in thirty soil samples taken from an oil field to detect phytotoxic effects. GI, is a cheap, fast and reproducible biological method for determining the toxicity of the soil, thus helping to characterize areas with contaminated soils. The results show that, after germination, Atriplex lampa (Moq. D.Dietri. and Prosopis denudans are more resistant in the contaminated soils of an oil field than the reference bioindicator (Lactuca sativa L..

  13. Effects of injection speed of test samples on the mouse bioassay for paralytic shellfish poisoning toxins

    Directory of Open Access Journals (Sweden)

    Hodaka Suzuki

    2013-06-01

    Full Text Available The mouse bioassay has been used as the official method for paralytic shellfish poisoning toxins detection in Japan since 1980. However, differences in the results of this assay, when performed by different investigators, have been noted despite the use of the same sample. This study was performed to examine the effect of the injection speed, a hypothetical cause of such differences, on the death time of mice. Speed-controlled injection of the toxin (at 12, 6, 3, and 1.5 mL/min into mice was performed using a syringe pump, and the death times of mice were measured. No statistically significant differences were found among the groups, even between fast injection (5 s and very slow injection (40 s, indicating that the injection speed may not be the crucial factor for this assay.

  14. Synthetic human calcitonin (Cibacalcin, Ciba-Geigy): use for radioimmunoassay and bioassay

    International Nuclear Information System (INIS)

    Two batches of synthetic human calcitonin (HCT) batch A =delivered until 1976, and batch B = distributed since 1977 from Ciba-Geigy, have been tested and compared biologically and radioimmunologically. In the bioassay B is almost twice as active as A when compared ampoule content and exerts a biological activity of 188 IU per mg pure HCT. In the radioimmunoassay there is no difference from each other in radioiodination and purification, but using them as standard and again comparing them on declared ampoule content, B contains twice as much immunological activity as A. For those, using HCT for analytic or biological purposes it is of importance to consider the increased hormone content of batch B with a twofold biological and immunological activity, in comparison to the preparations delivered before 1977. (author)

  15. Elemol and Amyris Oil Repel the Ticks Ixodes scapularis and Amblyomma americanum (Acari: Ixodidae) in Laboratory Bioassays

    Science.gov (United States)

    The essential oil from Amyris balsamifera (Rutaceae) and elemol, a principal constituent of the essential oil of Osage orange, Maclura pomifera (Moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, Ixodes sc...

  16. Using macroalgal δ15N bioassay to detect cruise ship waste water effluent inputs in Skagway, AK

    Science.gov (United States)

    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. Sensitivity bioassays of the Cnesterodon decemmaculatus and Pimephales promelasin a series of samples of effluent and reference toxicant

    Directory of Open Access Journals (Sweden)

    Gustavo Saona

    2015-12-01

    Full Text Available This study compared the toxicological sensitivity quantified by the 50% lethal dose of acute toxicity bioassays of Cnesterodon decemmaculatusand Pimephales promelasin benchmark exposure to toxic industrial effluents, wastewater effluents and reference toxicants. At the same time, the toxicological sensitivity of C. decemmaculatusrelated to the size was assayed. Both species were analyzed with 16 bioassays mated by the same substance or compound and a good agreement rL= 0.75 was observed. No significant differences in the overall analysis for effluents and potassium dichromate appeared in toxicological analysis of sensitivity to size. In contrast, significant difference in sensitivity was observed in assays with sodium dodecyl sulfate. Previous studies of the acute bioassays of C. decemmaculatusas well as the results obtained in this work accredit the use of this species in the ecotoxicological evaluation.This work contributes to generate specific ecotoxicological tools employing a native species (C. decemmaculatus and provides comparative information with an internationally accepted species used in reference bioassays (P. promelas. Progress of these studies as a priority research area will contribute to consolidate analytical tools, to develop professional skills and to strengthen institutions that manage the water resources in Uruguay.

  18. Cleavable DNA-protein hybrid molecular beacon: A novel efficient signal translator for sensitive fluorescence anisotropy bioassay.

    Science.gov (United States)

    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. PMID:26592607

  19. Long-Distance Signaling in bypass1 Mutants:Bioassay Development Reveals the bps Signal to Be a Metabolite

    Institute of Scientific and Technical Information of China (English)

    Emma Adhikari; Dong-Keun Lee; Patrick Giavalisco; Leslie E. Sieburth

    2013-01-01

    Root-to-shoot signaling is used by plants to coordinate shoot development with the conditions experienced by the roots.A mobile and biologically active compound,the bps signal,is over-produced in roots of an Arabidopsis thaliana mutant called bypass1 (bps1),and might also be a normally produced signaling molecule in wild-type plants.Our goal is to identify the bps signal chemically,which will then allow us to assess its production in normal plants.To identify any signaling molecule,a bioassay is required,and here we describe the development of a robust,simple,and quantitative bioassay for the bps signal.The developed bioassay follows the growth-reducing activity of the bps signal using the pCYCB1;1::GUS cell cycle marker.Wild-type plants carrying this marker,and provided the bps signal through either grafts or metabolite extracts,showed reduced cell division.By contrast,control grafts and treatment with control extracts showed no change in pCYCB1;1::GUS expression.To determine the chemical nature of the bps signal,extracts were treated with RNase A,Proteinase K,or heat.None of these treatments diminished the activity of bps1 extracts,suggesting that the active molecule might be a metabolite.This bioassay will be useful for future biochemical fractionation and analysis directed toward bps signal identification.

  20. Evaluation of the toxic effects of arsenite, chromate, cadmium, and copper using a battery of four bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Kyung-Seok; Lee, Pyeong-Koo [Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon (Korea, Republic of). Geologic Environment Div.; Kong, In Chul [Yeungnam Univ., Kyungbuk (Korea, Republic of). Dept. of Environmental Engineering

    2012-09-15

    The sensitivities of four different kinds of bioassays to the toxicities of arsenite, chromate, cadmium, and copper were compared. The different bioassays exhibited different sensitivities, i.e., they responded to different levels of toxicity of each of the different metals. However, with the exception of the {alpha}-glucosidase enzyme activity, arsenite was the most toxic compound towards all the tested organisms, exhibiting the highest toxic effect on the seeds of Lactuca, with an EC{sub 50} value of 0.63 mg/L. The sensitivities of Lactuca and Raphanus were greater than the sensitivities of two other kinds of seeds tested. Therefore, these were the seeds appropriate for use in a seed germination assay. A high revertant mutagenic ratio (5:1) of Salmonella typhimurium was observed with an arsenite concentration of 0.1 {mu}g/plate, indicative of a high possibility of mutagenicity. These different results suggested that a battery of bioassays, rather than one bioassay alone, is needed as a more accurate and better tool for the bioassessment of environmental pollutants. (orig.)

  1. Translating bioassay results to field population responses using a Leslie-matrix model for the marine amphipod Corophium volutator

    NARCIS (Netherlands)

    Smit, M.G.D.; Kater, B.J.; Jak, R.G.; Heuvel-Greve, van den M.J.

    2006-01-01

    Bioassays can be used for the assessment of sediment contamination. The response is classified based on a statistical scale indicating a certain effect percentage being significantly different from the controls (e.g. mortality classes of 0¿10%, 10¿20% etc.). The ecological relevance of this statisti

  2. Comparison of ICRP Publication 30 lung model-based predictions with measured bioassay data for airborne natural UO2 exposure

    International Nuclear Information System (INIS)

    In this paper a comparison is made between the build-up of U thorax burdens and the predicted total lung (lung and lymph) burden, based on the lung model provided in ICRP Publication 30 for a group of 29 atomic radiation workers at a Canadian fuel fabrication facility. A similar comparison is made between the predicted ratio of the total lung burden to urinary excretion and the ratio obtained from bioassay data. The study period for the comparison is 5 y. The inhalation input for the lung model calculations was derived from air-sampling data and the choice of particle size activity median aerodynamic diameter (AMAD) was guided by particle size measurements made at representative work locations. The pulmonary clearance half-times studied were 100, 250 and 500 d. For the purpose of this comparison, averaged exposure and averaged bioassay data for the group were used. This comparison indicates that for the conditions of this facility, the assumption of a 500-d pulmonary clearance half-time and a particle size of 1 micron (AMAD) may be too conservative. It is suggested that measurements of air concentrations and particle size used as input parameters for the ICRP Publication 30 lung model may be used to calculate bioassay parameters which may then be tested against bioassay data obtained as part of an operational health physics program, thereby giving a useful step towards defining a derived air concentration value for U in the workplace

  3. In vivo genotoxicity of furan in F344 rats at cancer bioassay doses.

    Science.gov (United States)

    Ding, Wei; Petibone, Dayton M; Latendresse, John R; Pearce, Mason G; Muskhelishvili, Levan; White, Gene A; Chang, Ching-Wei; Mittelstaedt, Roberta A; Shaddock, Joseph G; McDaniel, Lea P; Doerge, Daniel R; Morris, Suzanne M; Bishop, Michelle E; Manjanatha, Mugimane G; Aidoo, Anane; Heflich, Robert H

    2012-06-01

    Furan, a potent rodent liver carcinogen, is found in many cooked food items and thus represents a human cancer risk. Mechanisms for furan carcinogenicity were investigated in male F344 rats using the in vivo Comet and micronucleus assays, combined with analysis of histopathological and gene expression changes. In addition, formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III (EndoIII)-sensitive DNA damage was monitored as a measure of oxidative DNA damage. Rats were treated by gavage on four consecutive days with 2, 4, and 8mg/kg bw furan, doses that were tumorigenic in 2-year cancer bioassays, and with two higher doses, 12 and 16mg/kg. Rats were killed 3h after the last dose, a time established as producing maximum levels of DNA damage in livers of furan-treated rats. Liver Comet assays indicated that both DNA strand breaks and oxidized purines and pyrimidines increased in a near-linear dose-responsive fashion, with statistically significant increases detected at cancer bioassay doses. No DNA damage was detected in bone marrow, a non-target tissue for cancer, and peripheral blood micronucleus assays were negative. Histopathological evaluation of liver from furan-exposed animals produced evidence of inflammation, single-cell necrosis, apoptosis, and cell proliferation. In addition, genes related to apoptosis, cell-cycle checkpoints, and DNA-repair were expressed at a slightly lower level in the furan-treated livers. Although a mixed mode of action involving direct DNA binding cannot be ruled out, the data suggest that furan induces cancer in rat livers mainly through a secondary genotoxic mechanism involving oxidative stress, accompanied by inflammation, cell proliferation, and toxicity. PMID:22507866

  4. Chlorine disinfection by-products in wastewater effluent: Bioassay-based assessment of toxicological impact.

    Science.gov (United States)

    Watson, K; Shaw, G; Leusch, F D L; Knight, N L

    2012-11-15

    The potential ecological impact of disinfection by-products (DBPs) present in chlorinated wastewater effluents is not well understood. In this study, the chlorinated effluent of traditional wastewater treatment plants (WWTPs) and advanced water reclamation plants (AWRPs) supplying highly-treated recycled water were analyzed for nitrosamines and trihalomethanes (THMs), and a battery of bioassays conducted to assess effluent toxicity. An increase in general toxicity from DBPs was revealed for all wastewaters studied using an in vitro bioluminescence assay. Examples of androgenic activity and estrogenic activity arising from DBPs at specific sampling sites were also observed. The in vivo model (Artemia franciscana) was generally not adversely affected by exposure to DBPs from any of the chlorinated wastewaters studied. The observed toxicity could not be related to the concentrations of THMs and nitrosamines present, indicating that DBPs not monitored in this study were responsible for this. This work highlights the complexity of DBPs mixtures formed in chlorinated wastewaters, illustrating that toxicity of wastewater DBPs cannot be predicted by chemical monitoring of THMs and nitrosamines. The results suggest bioassays may be particularly useful monitoring tools in assessing toxicity arising from DBPs of these complex waters. The research concludes that DBPs formed in the chlorinated wastewaters studied can be toxic and may have a deleterious impact on aquatic organisms that are exposed to them, and therefore, that chlorination or chlorination/dechlorination may not be adequate treatment strategies for the protection of receiving waters. Chlorinated wastewater toxicity (from DBPs) is not well-understood in the Australian context, and this study serves to advise regulators on this issue. PMID:22981491

  5. Development of An ICR Mouse Bioassay for Toxicity Evaluatition in Neurotoxic Poistioning Toxins-Ctiontaminated Shellfish

    Institute of Scientific and Technical Information of China (English)

    WONG Chun Kwan; HUNG Patricia; KAM Kai Man

    2013-01-01

    Objective To develop an ICR (female) mouse bioassay (MBA) for toxicity ctionfirmatition and evaluatition of neurotoxins (brevetoxins)-ctiontaminated shellfish. Methods Brevetoxins (BTX-B) as a causative agent of neurotoxic shellfish poistioning (NSP) under different shellfish matrices were intraperittioneally injected at different doses into mice to study their toxic effects and to differentiate the range of lethal and sublethal dosages. Their sensitivity and specificity were analyzed with 2 competitive ELISA kits for quantitative determinatition of standard BTX-B and dihydroBTX-B under different shellfish matrix-diluent combinatitions. Detectition rates of MBA and two antibody-based assays for BTX-B from field NSP-positive shellfish samples were compared. Results BTX-B could be detected in shellfish tissues at ctioncentratition of 50-400 μg/100 g under shellfish matrix-Tween-saline media, which were appropriate to identify toxic shellfish at or above the regulatory limit (80 μg/100 g shellfish tissues). The LD50 identified was 455 μg/kg for BTX-B under general shellfish matrices (excluding oyster matrices) dissolved in Tween-saline. The presence of shellfish matrices, of oyster matrices in particular, retarded the occurrence of death and toxicity presentatition in mice. Two antibody-based assays, even in the presence of different shellfish matrix-diluent combinatitions, showed acceptable results in quantifying BTX-B and dihydroBTX-B well below the regulatory limit. Ctionclusition The two ELISA analyses agree favorably (correlatition coefficient, r≥0.96;Student's t-tests, P>0.05) with the developed bioassay.

  6. A novel bioassay for the activity determination of therapeutic human brain natriuretic peptide (BNP.

    Directory of Open Access Journals (Sweden)

    Lei Yu

    Full Text Available BACKGROUND: Recombinant human brain natriuretic peptide (rhBNP is an important peptide-based therapeutic drug indicated for the treatment of acute heart failure. Accurate determination of the potency of therapeutic rhBNP is crucial for the safety and efficacy of the drug. The current bioassay involves use of rabbit aortic strips, with experiments being complicated and time-consuming and markedly variable in results. Animal-less methods with better precision and accuracy should be explored. We have therefore developed an alternative cell-based assay, which relies on the ability of BNP to induce cGMP production in HEK293 cells expressing BNP receptor guanylyl cyclase-A. METHODOLOGY/PRINCIPAL FINDINGS: An alternative assay based on the measurement of BNP-induced cGMP production was developed. Specifically, the bioassay employs cells engineered to express BNP receptor guanylyl cyclase-A (GCA. Upon rhBNP stimulation, the levels of the second messager cGMP in these cells drastically increased and subsequently secreted into culture supernatants. The quantity of cGMP, which corresponds to the rhBNP activity, was determined using a competitive ELISA developed by us. Compared with the traditional assay, the novel cell-based assay demonstrated better reproducibility and precision. CONCLUSION/SIGNIFICANCE: The optimized cell-based assay is much simpler, more rapid and precise compared with the traditional assay using animal tissues. To our knowledge, this is the first report on a novel and viable alternative assay for rhBNP potency analysis.

  7. A miniature bioassay for testing the acute phytotoxicity of photosystem II herbicides on seagrass.

    Directory of Open Access Journals (Sweden)

    Adam D Wilkinson

    Full Text Available Photosystem II (PSII herbicides have been detected in nearshore tropical waters such as those of the Great Barrier Reef and may add to the pressure posed by runoff containing sediments and nutrients to threatened seagrass habitats. There is a growing number of studies into the potential effects of herbicides on seagrass, generally using large experimental setups with potted plants. Here we describe the successful development of an acute 12-well plate phytotoxicity assay for the PSII herbicide Diuron using isolated Halophila ovalis leaves. Fluorescence images demonstrated Diuron affected the entire leaf surface evenly and responses were not influenced by isolating leaves from the plant. The optimum exposure duration was 24 h, by which time the inhibition of effective quantum yield of PSII (∆F/F(m' was highest and no deterioration of photosystems was evident in control leaves. The inhibition of ∆F/F(m' by Diuron in isolated H. ovalis leaves was identical to both potted and hydroponically grown plants (with leaves remaining attached to rhizomes, indicating similar reductions in photosynthetic activity in these acute well-plate assays. The sensitivity of the assay was not influenced by irradiance (range tested 40 to 400 μmol photons m(-2 s(-1. High irradiance, however, caused photo-oxidative stress in H. ovalis and this generally impacted in an additive or sub-additive way with Diuron to damage PSII. The bioassay using isolated leaves is more rapid, uses far less biological material and does not rely on specialised aquarium facilities in comparison with assays using potted plants. The development and validation of this sensitive bioassay will be useful to reliably screen and monitor the phytotoxicity of existing and emerging PSII herbicides and contribute to risk assessments and water quality guideline development in the future.

  8. Assessment of N and P in organic fertilizer using the missing element technique and a microbial bioassay

    International Nuclear Information System (INIS)

    Assessment of N and P in organic fertilizers using the missing element technique and a microbial bioassay.Through a greenhouse bioassay, using sorghum (Sorghum vulgare) as a test plant, and a microbial assay the availability of N and P in 6 substrates was determined, namely: soil alone and in combination with several organic amendments 10% W/W of chicken manure (CM), compost (C), bocashi (B), vermicompost (V) and coffe hulls (Br). In the microbial assay a complete randomized design with 6 replicates was used; the microbial biomass (BM) was determined 2 days after the glucose amendment of each treatment. In both bioassays a 2 X 2 factorial (N and P fertilization) was establish and the following combinations resulted: +N, +P, +P+N and -P-N (control). For the greenhouse experiment, a complete randomized design with 4 replicates was used. Above-ground plant material of sorghum was harvested 34 days after showing to determine plant dry weight (PS) and content of N and P. Both assays showed a response to the soil amendment with N and P. Soil treatments with CM, C and B showed the highest values of PS and BM. Soil treatment with CM amended with N, P or both did not showed a response in PS or BM, in C and B there was a response to N addition but not to P. In treatments with V and Br, the lowest values for PS and BM were obtained, and there was a growth response to N and P. Both bioassays were able to pinpoint N and P defficiencies in the soil as well in some of the mixtures of soil with organic amendments. A high correlation was encountered between the greenhouse assay and the microbial bioassay (r= 0.86, P=0.0001). Therefore, the microbial bioassay can be a cheaper alternative to the plant bioassay not only to evaluate the nutritional quality of compost but also to identify nutrient deficiencies in soils as well as in substrates amended with organic fertilizers. (Author)

  9. A review of metal (Pb and Zn) sensitive and pH tolerant bioassay organisms for risk screening of metal-contaminated acidic soils

    International Nuclear Information System (INIS)

    To improve risk estimates at the screening stage of Ecological Risk Assessment (ERA), short duration bioassays tailored to undisturbed soil cores from the contaminated site could be useful. However, existing standardized bioassays use disturbed soil samples and often pH sensitive organisms. This is a problem as naturally acidic soils are widespread. Changing soil properties to suit the test organism may change metal bioavailability, leading to erroneous risk estimates. For bioassays in undisturbed soil cores to be effective, species able to withstand natural soil properties must be identified. This review presents a critical examination of bioassay species' tolerance of acidic soils and sensitivity to metal contaminants such as Pb and Zn. Promising organisms include; Dendrobaena octaedra, Folsomia candida, Caenorhabditis elegans, Oppia nitens, Brassica rapa, Trifolium pratense, Allium cepa, Quercus rubra and Acer rubrum. The MetSTICK test and the Bait lamina test were also identified as suitable microorganism tests. -- Highlights: •Risk screening of metal contaminated soils should consider metal bioavailability. •Metal bioavailability is dependent on soil properties such as pH. •Many standardized bioassay organisms are sensitive to acidic soils. •This review identifies acid tolerant and metal sensitive bioassays and species. •The identified tests can improve risk screening of acidic metal contaminated soil. -- This review identifies bioassay species able to withstand naturally acidic soils while being sensitive to metal contaminants

  10. Effect-based trigger values for in vitro bioassays: Reading across from existing water quality guideline values.

    Science.gov (United States)

    Escher, Beate I; Neale, Peta A; Leusch, Frederic D L

    2015-09-15

    Cell-based bioassays are becoming increasingly popular in water quality assessment. The new generations of reporter-gene assays are very sensitive and effects are often detected in very clean water types such as drinking water and recycled water. For monitoring applications it is therefore imperative to derive trigger values that differentiate between acceptable and unacceptable effect levels. In this proof-of-concept paper, we propose a statistical method to read directly across from chemical guideline values to trigger values without the need to perform in vitro to in vivo extrapolations. The derivation is based on matching effect concentrations with existing chemical guideline values and filtering out appropriate chemicals that are responsive in the given bioassays at concentrations in the range of the guideline values. To account for the mixture effects of many chemicals acting together in a complex water sample, we propose bioanalytical equivalents that integrate the effects of groups of chemicals with the same mode of action that act in a concentration-additive manner. Statistical distribution methods are proposed to derive a specific effect-based trigger bioanalytical equivalent concentration (EBT-BEQ) for each bioassay of environmental interest that targets receptor-mediated toxicity. Even bioassays that are indicative of the same mode of action have slightly different numeric trigger values due to differences in their inherent sensitivity. The algorithm was applied to 18 cell-based bioassays and 11 provisional effect-based trigger bioanalytical equivalents were derived as an illustrative example using the 349 chemical guideline values protective for human health of the Australian Guidelines for Water Recycling. We illustrate the applicability using the example of a diverse set of water samples including recycled water. Most recycled water samples were compliant with the proposed triggers while wastewater effluent would not have been compliant with a few

  11. Low-Level Plutonium Bioassay Measurements at the Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T; Brown, T; Hickman, D; Marchetti, A; Williams, R; Kehl, S

    2007-06-18

    Plutonium-239 ({sup 239}Pu) and plutonium-240 ({sup 240}Pu) are important alpha emitting radionuclides contained in radioactive debris from nuclear weapons testing. {sup 239}Pu and {sup 240}Pu are long-lived radionuclides with half-lives of 24,400 years and 6580 years, respectively. Concerns over human exposure to plutonium stem from knowledge about the persistence of plutonium isotopes in the environment and the high relative effectiveness of alpha-radiation to cause potential harm to cells once incorporated into the human body. In vitro bioassay tests have been developed to assess uptakes of plutonium based on measured urinary excretion patterns and modeled metabolic behaviors of the absorbed radionuclides. Systemic plutonium absorbed by the deep lung or from the gastrointestinal tract after ingestion is either excreted or distributed to other organs, primarily to the liver and skeleton, where it is retained for biological half-times of around 20 and 50 years, respectively. Dose assessment and atoll rehabilitation programs in the Marshall Islands have historically given special consideration to residual concentrations of plutonium in the environment even though the predicted dose from inhalation and/or ingestion of plutonium accounts for less than 5% of the annual effective dose from exposure to fallout contamination. Scientists from the Lawrence Livermore National Laboratory (LLNL) have developed a state-of-the-art bioassay test to assess urinary excretion rates of plutonium from Marshallese populations. This new heavy-isotope measurement system is based on Accelerator Mass Spectrometry (AMS). The AMS system at LLNL far exceeds the standard measurement requirements established under the latest United States Department of Energy (DOE) regulation, 10CFR 835, for occupational monitoring of plutonium, and offers several advantages over classical as well as competing new technologies for low-level detection and measurement of plutonium isotopes. The United States

  12. Comparative study of two bioassays with weakened duckweed and yeast treated with homeopathic preparations

    Directory of Open Access Journals (Sweden)

    Ursula Wolf

    2012-09-01

    Full Text Available In homeopathic basic research, the question as to the most adequate test systems and apt methodology is still open. This investigation examined the hypothesis that more complex organisms show stronger reactions to homeopathic remedies than less complex ones. We compared two Arsenic (As5+ stressed bioassays with duckweed (Lemna gibba, a multi-cellular autotrophic organism and yeast (Saccharomyces cerevisiae, a single-cellular heterotrophic organism regarding their response to homeopathic preparations [1]. For duckweed, growth rates of leaf area and leaf number were evaluated. For yeast, growth kinetics were determined by measuring slope, yield and Et50 (point in time when yield was half maximum of the sigmoid growth curve. The experiments with duckweed and yeast were performed in parallel (same day, same location and identical homeopathic preparations. After screening 17 substances, three homeopathic preparations (Arsenicum album, nosode, gibberellic acid were chosen for repeated experimental series [2]. Five independent experiments were conducted for each remedy with both organisms in parallel. Potency levels used were in the range of 17x–33x for duckweed and 17x–30x for yeast. To control for test system stability, systematic negative control experiments were conducted over the complete experimentation period. All experiments were blinded and randomized. The systematic negative control experiments did not yield any significant effects. Application of potentized Arsenicum album in the duckweed bioassay yielded the largest effects compared to water controls without remedies for the parameters leaf area and leaf number (p<0.001 [1, 3]. Potentized nosode preparations also had significant effects on duckweed's leaf area and leaf number (p<0.01. Growth was enhanced across all potency levels. In the yeast system the three homeopathic remedies did not show any significant effects on any growth curve parameter. The

  13. Synthesis, Characterization, and Application of Metal-Chelating Polymers for Mass Cytometric Bioassays

    Science.gov (United States)

    Majonis, Daniel

    This thesis describes the synthesis, characterization, and application of metal-chelating polymers for mass-cytometric bioassays. Mass cytometry is a cell characterization technique in which cells are injected individually into an ICP-MS detector. Signal is provided by staining cell-surface or intracellular antigens with metal-labeled antibodies (Abs). These Abs are labeled through the covalent attachment of metal-chelating polymers which carry multiple copies of a lanthanide isotope. In this work, my first goal was to develop a facile, straightforward synthesis of a new generation of metal-chelating polymers. The synthesis began with reversible addition-fragmentation chain transfer polymerization, and was followed by numerous post-polymerization pendant group transformations to introduce DTPA lanthanide chelators to every repeat unit, and a maleimide at the end of the chain. The second goal was to apply these metal-chelating polymers in bioassay experiments. The DTPA groups were loaded with lanthanide ions, and the maleimide group was used to covalently attach the polymer to an Ab. This goat anti-mouse conjugate was found to carry an average of 2.4 +/- 0.3 polymer chains. Then, primary Ab conjugates were prepared and used in an 11-plex mass cytometry assay in the characterization of umbilical cord blood cells. The third goal was to expand the multiplexity of the assay. In current technology, the number of Abs that can be monitored simultaneously is limited to the 31 commercially available, stable lanthanide isotopes. Thus, I had an interest in preparing metal-chelating polymers that could carry other metals in the 100-220 amu range. I synthesized polymers with four different polyaminocarboxylate ligands, and investigated the loading of palladium and platinum ions into these polymers. Polymer-Ab conjugates prepared with palladium- and platinum-loaded polymers gave curious results, in that only dead cells were recognized. The fourth goal was to create dual

  14. Facile synthesis of methotrexate intercalated layered double hydroxides: Particle control, structure and bioassay explore

    International Nuclear Information System (INIS)

    To study the influence of particle size on drug efficacy and other properties, a series of methotrexate intercalated layered double hydroxides (MTX/LDHs) were synthesized through the traditional coprecipitation method, using a mixture of water and polyethylene glycol (PEG-400) as the solvent. To adjust the particle size of MTX/LDHs, the dropping way, the volume ratio of water to PEG-400 and different hydrothermal treatment time changed accordingly, and the results indicate that the particle size can be controlled between 90 and 140 nm. Elemental C/H/N and inductive coupled plasma (ICP) analysis indicated that different synthesis conditions almost have no effect on the compositions of the nanohybrids. X-ray diffraction (XRD) patterns manifested the successful intercalation of MTX anions into the LDH interlayers, and it's also found out that different volume ratios of water to PEG-400 and variable dropping way can affect the crystallinity of the final samples, i.e., the volume ratio of 3:1 and pH decreasing are proved to be optimum conditions. Furthermore, both antiparallel monolayer and bilayers adopting different orientations are suggested for four samples from XRD results. Fourier transform infrared spectroscopy (FTIR) investigations proved the coexistence of CO32− and MTX anions in the interlayer of the nanohybrids. MTX/LDH particles exhibited hexagonal platelet morphology with round corner and different dropping ways can affect the morphology greatly. Moreover, a DSC study indicated that longer time treatment can weaken the bond between the MTX anions and LDH layers. The kinetic release profiles told us that larger MTX/LDH particles have enhanced the ability of LDH layers to protect interlayer molecules. At last, the bioassay study indicated that the nanohybrids with larger diameters have higher tumor suppression efficiency. - Graphical abstract: A series of methotrexate intercalated layered double hydroxides were synthesized by changing the dropping way

  15. Facile synthesis of methotrexate intercalated layered double hydroxides: Particle control, structure and bioassay explore

    Energy Technology Data Exchange (ETDEWEB)

    Tian, De-Ying; Liu, Zhen-Lei [Jiangsu Key Laboratory of Biofunctional Material, College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210023 (China); Li, Shu-Ping, E-mail: lishuping@njnu.edu.cn [Jiangsu Key Laboratory of Biofunctional Material, College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210023 (China); Li, Xiao-Dong [Jiangsu Key Laboratory of Biofunctional Material, College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210023 (China); Shenzhen Research Institute of Xiamen University, Shenzhen 518057 (China)

    2014-12-01

    To study the influence of particle size on drug efficacy and other properties, a series of methotrexate intercalated layered double hydroxides (MTX/LDHs) were synthesized through the traditional coprecipitation method, using a mixture of water and polyethylene glycol (PEG-400) as the solvent. To adjust the particle size of MTX/LDHs, the dropping way, the volume ratio of water to PEG-400 and different hydrothermal treatment time changed accordingly, and the results indicate that the particle size can be controlled between 90 and 140 nm. Elemental C/H/N and inductive coupled plasma (ICP) analysis indicated that different synthesis conditions almost have no effect on the compositions of the nanohybrids. X-ray diffraction (XRD) patterns manifested the successful intercalation of MTX anions into the LDH interlayers, and it's also found out that different volume ratios of water to PEG-400 and variable dropping way can affect the crystallinity of the final samples, i.e., the volume ratio of 3:1 and pH decreasing are proved to be optimum conditions. Furthermore, both antiparallel monolayer and bilayers adopting different orientations are suggested for four samples from XRD results. Fourier transform infrared spectroscopy (FTIR) investigations proved the coexistence of CO{sub 3}{sup 2−} and MTX anions in the interlayer of the nanohybrids. MTX/LDH particles exhibited hexagonal platelet morphology with round corner and different dropping ways can affect the morphology greatly. Moreover, a DSC study indicated that longer time treatment can weaken the bond between the MTX anions and LDH layers. The kinetic release profiles told us that larger MTX/LDH particles have enhanced the ability of LDH layers to protect interlayer molecules. At last, the bioassay study indicated that the nanohybrids with larger diameters have higher tumor suppression efficiency. - Graphical abstract: A series of methotrexate intercalated layered double hydroxides were synthesized by changing the

  16. Bioassay measurements of individuals living near the US Department of Energy's Hanford Site in Washington State, Fall 1985

    International Nuclear Information System (INIS)

    The purpose of the bioassay measurements was to provide individuals, living within a specific area near the Hanford Site, information on the current levels of radionuclides in their bodies. The measurements included whole body counter (in vivo) examinations and urine sample analyses for detecting the presence of major radionuclides related to current and historical operations at Hanford. Notifications of the special measurements were sent by letter to 515 residences in north Franklin County. Eighty-nine individuals from 52 of the 515 residences requested and received whole body counts. Of these, 32 also provided urine samples. The measurements gave no evidence of unusual levels of radioactivity in any individual. The ability of bioassay measurements to detect the presence of radioactivity in an individual following an exposure is dependent on the quality of the measurement and the nature of the exposure. This report includes a discussion of the capability, under various circumstances, of the measurements that were provided

  17. Addressing the recovery of feeding rates in post-exposure feeding bioassays: Cyathura carinata as a case study

    Energy Technology Data Exchange (ETDEWEB)

    Pais-Costa, Antonia Juliana [IMAR—Institute of Marine Research, MARE—Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra (Portugal); Acevedo, Pelayo [SaBio IREC, Instituto de Investigación en Recursos Cinegéticos (UCLM-CSIC-JCCM), Ciudad Real 13005 (Spain); Marques, João Carlos [IMAR—Institute of Marine Research, MARE—Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra (Portugal); Martinez-Haro, Mónica, E-mail: monica.martinezharo@gmail.com [IMAR—Institute of Marine Research, MARE—Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra (Portugal)

    2015-02-15

    Post-exposure bioassays are used in environmental assessment as a cost-effective tool, but the effects of organism's recovery after exposure to pollutant has not yet been addressed in detail. The recoveries of post-exposure feeding rates after being exposed to two sublethal concentrations of cadmium during two different exposure periods (48 h and 96 h) were evaluated under laboratory conditions using the estuarine isopod Cyathura carinata. Results showed that feeding depression was a stable endpoint up to 24 h after cadmium exposure, which is useful for ecotoxicological bioassays. - Highlights: • We studied recovery of post-exposure feeding rates 48–96 h after cadmium exposure. • The assay is based on the isopod Cyathura carinata. • Post-exposure feeding inhibition is a stable sublethal endpoint.

  18. Combined effects of estrogenic chemicals with the same mode of action using an estrogen receptor binding bioassay.

    Science.gov (United States)

    Yang, Rong; Li, Na; Ma, Mei; Wang, Zijian

    2014-11-01

    The increasing amounts of various estrogenic chemicals coexisting in the aquatic environment may pose environmental risks. While the concept of estradiol equivalent (EEQ) has been frequently applied in studying estrogenic mixtures, few experiments have been done to prove its reliability. In this study, the reliability of EEQ and the related model concentration addition (CA) was verified based on the two-hybrid recombinant yeast bioassay when all mixture components had the same mode of action and target of action. Our results showed that the measured estrogenic effects could be well predicted by CA and EEQ for all laboratory-made mixtures using two designs, despite the varying estrogenic activity, concentration levels and ratios of the test chemicals. This suggests that when an appropriate endpoint and its relevant bioassay are chosen, CA should be valid and the application of EEQ in predicting the effect of non-equi-effect mixtures is feasible. PMID:25461542

  19. Phytochemical and toxicity evaluation of Phaleria macrocarpa (Scheff. Boerl by MCF-7 cell line and brine shrimp lethality bioassay

    Directory of Open Access Journals (Sweden)

    Abul Kalam Azad

    2016-01-01

    Full Text Available Objective: To evaluate the cytotoxicity of Phaleria macrocarpa fruits extracts. Methods: The cytotoxicity test was carried out by in vitro MCF-7 cell line and in vivo brine shrimp lethality bioassay. Results: The preliminary phytochemical test showed the presence of alkaloids, carbohydrate, glycosides, saponin, terpene, steroids, phenols and flavonoids. The MTT-assay results showed that the highest percentage of cell viability was 106.23% at concentration of 1.25 µL and the lowest percentage was 13.04% at concentration of 10 µL. Conclusions: The MTT-assay and brine shrimp lethality bioassay results showed that the extract was non-toxic and it would be consumable as a herbal remedy.

  20. Phytochemical and toxicity evaluation ofPhaleria macrocarpa (Scheff.) Boerl by MCF-7 cell line and brine shrimp lethality bioassay

    Institute of Scientific and Technical Information of China (English)

    Abul Kalam Azad; Wan Mohd Azizi Wan Sulaiman; Nushrat Khan Sunzida

    2016-01-01

    Objective:To evaluate the cytotoxicity ofPhaleria macrocarpa fruits extracts. Methods: The cytotoxicity test was carried out byin vitroMCF-7 cell line andin vivo brine shrimp lethality bioassay. Results: The preliminary phytochemical test showed the presence of alkaloids, carbohydrate, glycosides, saponin, terpene, steroids, phenols and flavonoids. TheMTT-assay results showed that the highest percentage of cell viability was 106.23% at concentration of 1.25µL and the lowest percentage was 13.04% at concentration of 10µL. Conclusions:TheMTT-assay and brine shrimp lethality bioassay results showed that the extract was non-toxic and it would be consumable as a herbal remedy.

  1. Terbium to quantum rod Förster resonance energy transfer for homogeneous bioassays with picomolar detection limits

    International Nuclear Information System (INIS)

    We report on the proof-of-principle of using semiconductor nanorods (quantum rods; QRs) in homogeneous Förster resonance energy transfer (FRET) bioassays. Terbium complexes (Tb) with long photoluminescence lifetimes were used as FRET donors, and biological recognition was accomplished by biotin-QR to Tb-streptavidin binding. Time-resolved and steady-state spectroscopy were used to investigate varying relative donor/acceptor concentrations and different lengths of polyethylene glycol (PEG)-based surface coatings. Homogeneous bioassays displayed low picomolar detection limits in 150 μL samples, independent of whether 1 and 10 kDa biotin-PEG-SH surface ligands were used. The results suggest that the combination of Tb-to-QR FRET with time-gated detection may become a powerful tool for homogeneous biosensing. (author)

  2. Addressing the recovery of feeding rates in post-exposure feeding bioassays: Cyathura carinata as a case study

    International Nuclear Information System (INIS)

    Post-exposure bioassays are used in environmental assessment as a cost-effective tool, but the effects of organism's recovery after exposure to pollutant has not yet been addressed in detail. The recoveries of post-exposure feeding rates after being exposed to two sublethal concentrations of cadmium during two different exposure periods (48 h and 96 h) were evaluated under laboratory conditions using the estuarine isopod Cyathura carinata. Results showed that feeding depression was a stable endpoint up to 24 h after cadmium exposure, which is useful for ecotoxicological bioassays. - Highlights: • We studied recovery of post-exposure feeding rates 48–96 h after cadmium exposure. • The assay is based on the isopod Cyathura carinata. • Post-exposure feeding inhibition is a stable sublethal endpoint

  3. Development and bioassay of transgenic Chinese cabbage expressing potato proteinase inhibitor II gene.

    Science.gov (United States)

    Zhang, Junjie; Liu, Fan; Yao, Lei; Luo, Chen; Yin, Yue; Wang, Guixiang; Huang, Yubi

    2012-06-01

    Lepidopteran larvae are the most injurious pests of Chinese cabbage production. We attempted the development of transgenic Chinese cabbage expressing the potato proteinase inhibitor II gene (pinII) and bioassayed the pest-repelling ability of these transgenic plants. Cotyledons with petioles from aseptic seedlings were used as explants for Agrobacterium-mediated in vitro transformation. Agrobacterium tumefaciens C58 contained the binary vector pBBBasta-pinII-bar comprising pinII and bar genes. Plants showing vigorous PPT resistance were obtained by a series concentration selection for PPT resistance and subsequent regeneration of leaf explants dissected from the putative chimera. Transgenic plants were confirmed by PCR and genomic Southern blotting, which showed that the bar and pinII genes were integrated into the plant genome. Double haploid homozygous transgenic plants were obtained by microspore culture. The pinII expression was detected using quantitative real time polymerase chain reaction (qRT-PCR) and detection of PINII protein content in the transgenic homozygous lines. Insect-feeding trials using the larvae of cabbage worm (Pieris rapae) and the larvae of the diamondback moth (Plutella xylostella) showed higher larval mortality, stunted larval development, and lower pupal weights, pupation rates, and eclosion rates in most of the transgenic lines in comparison with the corresponding values in the non-transformed wild-type line. PMID:23136521

  4. Improvement of Chemically-activated Luciferase Gene Expression Bioassay for Detection of Dioxin-like Chemicals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To improve the chemically-activated luciferase expression (CALUX)bioassay for detection of dioxin-like chemicals (DLCs) based on the toxicity mechanisms of DLCs. Method A recombinant vector was constructed and used to transfect human hepatoma (HepG2). The expression of this vector was 10-100 folds higher than that of pGL2used in previous experiments. The transfected cells showed aromatic hydrocarbon receptor (AhR)-meditated luciferase gene expression. The reliability of luciferase induction in this cell line as a reporter of AhR-mediated toxicity was evaluated, the optimal detection time was examined and a comparison was made by using the commonly used ethoxyresoufin-Odeethylase (EROD) activity induction assay. Result The results suggested that the luciferase activity in recombinant cells was peaked at about 4 h and then decreased to a stable activity by 14 h after TCDD treatment. The detection limit of this cell line was 0.1 lpmol/L, or 10-fold lower than in previous studies, with a linear range from 1 to 100pmol/L, related coefficient of 0.997, and the coefficient of variability (CV) of 15-30%,Conclusion The luciferase induction is 30-fold more sensitive than EROD induction, the detection time is 68 h shorter and the detection procedure is also simpler.

  5. Characterization of dimeric forms of human pituitary growth hormone by bioassay, radioreceptor assay, and radioimmunoassay

    International Nuclear Information System (INIS)

    Seven highly purified dimeric forms of human pituitary growth hormone, composed of the monomeric forms 20 K hGH, 22K hGH and 24 k hBH linked together by noncovalent or covalent bounds, have been characterized by an in vitro bioassay (the Nb2 assay), a radioreceptor assay and a radioimmunoassay. Considerable differences in the ability to displace labelled recombinant hGH were observed in the radioreceptor assay. The seven dimeric forms varied over a range between 22 K hGH (most effective) and 20 K hGH. The three covalently-linked dimeric forms had nearly identical affinity constants. The mitogenic action of all but one of the hGH dimers in the Nb2 assay was in the same mutual order as the receptor binding activity in the radioreceptor assay. In the RIA, all dose-response curves were parallel except for those obtained with 20 K hGH and with the dimeric form (20 K-20 K)hGH. In this assay, dimeric variants of the constituents 22 K hGH and 24 K hGH were approximately twice as active as 22 K hGH on a molar basis, suggesting about the same affinity between the the antibodies and each of the monomeric forms. Determination of the amino acid compositions of the dimeric forms provided support for their content of monomeric constituents as established earlier by electrophoretic analysis. (author)

  6. Bioassay and Identification of Root Exudates of Three Fruit Tree Species

    Institute of Scientific and Technical Information of China (English)

    Jiang-Hong Zhang; Zhi-Quan Mao; Li-Qin Wang; Huai-Rui Shu

    2007-01-01

    A laboratory bioassay was designed to determine the allelopathic potential of root exudates of three fruit tree species on apple germination. The results showed that root exudates of apple (Malus pumila L.) and peach (Prunus persica L.), each at concentrations of 0.02 and 0.2 mg/L, inhibited germination and radicle growth of apple seeds by 56.7%, 60.7%, 51.5%, and 59.3%, respectively. The corresponding shoot growth inhibition rate was 49.5%, 46.7%, 36.4%, and 44%, respectively. Root exudates of jujube (Ziziphus jujuba Mill.) had no significant effect on apple seeds.Qualitative determination of root exudates of apple, peach, and jujube tree was developed with gas chromatography-mass spectrometry. The root exudates of apple seedlings mainly contain organic acids, glycol, esters, and benzenphenol derivatives. Peach root exudates contained phenolic acids and benzenphenol derivatives in addition to two unidentified compounds. The root exudates of jujube did not contain any phenolic acids.

  7. Hazard characterization and identification of a former ammunition site using microarrays, bioassays, and chemical analysis.

    Science.gov (United States)

    Eisentraeger, Adolf; Reifferscheid, Georg; Dardenne, Freddy; Blust, Ronny; Schofer, Andrea

    2007-04-01

    More than 100,000 tons of 2,4,6-trinitrotoluene were produced at the former ammunition site Werk Tanne in Clausthal-Zellerfeld, Germany. The production of explosives and consequent detonation in approximately 1944 by the Allies caused great pollution in this area. Four soil samples and three water samples were taken from this site and characterized by applying chemical-analytical methods and several bioassays. Ecotoxicological test systems, such as the algal growth inhibition assay with Desmodesmus subspicatus, and genotoxicity tests, such as the umu and NM2009 tests, were performed. Also applied were the Ames test, according to International Organization for Standardization 16240, and an Ames fluctuation test. The toxic mode of action was examined using bacterial gene profiling assays with a battery of Escherichia coli strains and with the human liver cell line hepG2 using the PIQOR Toxicology cDNA microarray. Additionally, the molecular mechanism of 2,4,6-trinitrotoluene in hepG2 cells was analyzed. The present assessment indicates a danger of pollutant leaching for the soil-groundwater path. A possible impact for human health is discussed, because the groundwater in this area serves as drinking water. PMID:17447547

  8. Towards the development of an embryotoxicity bioassay with terrestrial snails: Screening approach for cadmium and pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Druart, Coline; Scheifler, Renaud [Department of Chrono-Environment, University of Franche-Comte, UMR UFC/CNRS 6249 usc INRA, Place Leclerc, F-25030 Besancon Cedex (France); Vaufleury, Annette de, E-mail: annette.devaufleury@univ-fcomte.fr [Department of Chrono-Environment, University of Franche-Comte, UMR UFC/CNRS 6249 usc INRA, Place Leclerc, F-25030 Besancon Cedex (France)

    2010-12-15

    Currently no bioassays are available to assess the embryotoxicity of chemicals with terrestrial soil invertebrates. We therefore presented a new method for embryotoxicity testing with snail eggs: a relevant biological material that incubates in soil and that can be exposed to contaminants from leachates and soil solution. The effects of aqueous solutions of two herbicide formulations, Reglone (active ingredient (a.i.), diquat) and Roundup or its a.i., glyphosate, of a surfactant (Agral 90, a.i., nonylphenol polyethoxylates) and of cadmium (Cd) were studied. Endpoints were the hatching success and observations of embryo abnormalities after exposure. Roundup was found to be more toxic than its a.i. alone (EC50{sub a.i.} = 18 mg/l and about 1300 mg/l, respectively). Reglone (EC50{sub a.i.} = 0.72 mg/l) and Agral (EC50{sub a.i.} {approx} 50 mg/l) were also tested together, revealing that Reglone accounted for more than 99% of the mixture's toxicity. An antagonistic interaction between the two substances was found. For Cd (EC50 = 3.9 mg/l), a significant transfer from exposure medium to eggs was emphasized, particularly affecting the albumen. Abnormalities of embryogenesis in non-hatched embryos depended on the substance and the concentration considered.

  9. Toxicity Appraisal of Untreated Dyeing Industry Wastewater Based on Chemical Characterization and Short Term Bioassays.

    Science.gov (United States)

    Akhtar, Muhammad Furqan; Ashraf, Muhammad; Javeed, Aqeel; Anjum, Aftab Ahmad; Sharif, Ali; Saleem, Ammara; Akhtar, Bushra; Khan, Abdul Muqeet; Altaf, Imran

    2016-04-01

    Characterizing wastewaters only on a chemical basis may be insufficient owing to their complex nature. The purpose of this study was to assess toxicity of textile dyeing wastewater based on analytical techniques and short term toxicity based bioassays. In this study, screening of the fractionated wastewater through GC-MS showed the presence of phenols, phthalic acid derivatives and chlorpyrifos. Metal analysis revealed that chromium, arsenic and mercury were present in amounts higher than the wastewater discharge limits. Textile dyeing wastewater was found to be highly mutagenic in the Ames test. DNA damage in sheep lymphocytes decreased linearly with an increase in the dilution of wastewater. MTT assay showed that 8.3 percent v/v wastewater decreased cell survival percentage to 50 %. It can be concluded from this study that short term toxicity tests such as Ames test, in vitro comet assay, and cytotoxicity assays may serve as useful indicators of wastewater pollution along with their organic and inorganic chemical characterizations. PMID:26920697

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

    Energy Technology Data Exchange (ETDEWEB)

    Bihl, D.E.; Lynch, T.P.; Carbaugh, E.H.; Sula, M.J.

    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 plutonium 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.

  11. Methotrexate intercalated layered double hydroxides with the mediation of surfactants: Mechanism exploration and bioassay study

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Chao-Fan; Tian, De-Ying; Li, Shu-Ping, E-mail: lishuping@njnu.edu.cn; Li, Xiao-Dong

    2015-12-01

    Methotrexatum intercalated layered double hydroxides (MTX/LDHs) hybrids were synthesized by the co-precipitation method and three kinds of nonionic surfactants with different hydrocarbon chain lengths were used. The resulting hybrids were then characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). XRD and FTIR investigations manifest the successful intercalation of MTX anions into the interlayer of LDHs. TEM graphs indicate that the morphology of the hybrids changes with the variation of the chain length of the surfactants, i.e., the particles synthesized using polyethylene glycol (PEG-7) present regular disc morphology with good monodispersity, while samples with the mediation of alkyl polyglycoside (APG-14) are heavily aggregated and samples with the addition of polyvinylpyrrolidone (PVP-10) exhibit irregular branches. Furthermore, the release and bioassay experiments show that monodisperse MTX/LDHs present good controlled-release and are more efficient in the suppression of the tumor cells. - Highlights: • Surfactants could be used to modify the dispersing state of MTX/LDHs hybrids. • Surfactants have great effect on the morphology of MTX/LDHs hybrids. • MTX/LDHs with good monodisperse degree are more efficient in the suppression of the tumor cells.

  12. Characterization of urinary volatiles in Swiss male mice (Mus musculus): bioassay of identified compounds

    Indian Academy of Sciences (India)

    S Achiraman; G Archunan

    2002-12-01

    The present study was carried out to investigate the chemical nature of the urine of male mice and to assess its bioactivity. Urine of mature male mice was extracted with dichloromethane (1 : 1 ratio v/v) and analysed by gas-chromatography linked mass-spectrometry (GC-MS). Ten different compounds such as alkanes, alcohols, etc. were detected in the urine. Among the ten, five compounds are specific to males, namely 3-cyclohexene-1-methanol (I), 3-amino-s-triazole (II), 4-ethyl phenol (III), 3-ethyl-2,7-dimethyl octane (IV) and 1-iodoundecane (V). The compound, 4-ethylphenol, has been previously reported in several strains of male mice. Furthermore, the compounds (II) and (IV) are similar to 2-sec-butylthiazole and dehydro-exo-brevicomin compounds which have already been reported in male mice. Bioassay revealed that compounds (II), (III) and (IV) were responsible for attracting females and in inducing aggression towards males, as compared to the other compounds, i.e. (I) and (V). The results indicate that these three volatiles (II, III and IV) of male mice appear to act as attractants of the opposite sex.

  13. Chemical and bioassay techniques to authenticate quality of the anti-leishmanial drug miltefosine.

    Science.gov (United States)

    Kaur, Harparkash; Seifert, Karin; Hawkes, Geoffrey E; Coumbarides, Gregory S; Alvar, Jorge; Croft, Simon L

    2015-06-01

    Miltefosine, an effective oral treatment of visceral leishmaniasis (VL), was selected in May 2005, by the governments of India, Nepal, and Bangladesh for the elimination of VL. However, abnormally high treatment failure rates reported in patients in Bangladesh, given a miltefosine generic product ("Miltefos", Popular Pharmaceuticals Ltd.) during 2008, led the World Health Organization (WHO) to procure this formulation for quality testing. Proton ((1)H) and phosphorous ((31)P) nuclear magnetic resonance (NMR) analyses of the Miltefos™ capsules did not give the peaks defined for Impavido®, the quality assured VL treatment product from Aeterna Zentaris. Contents of capsules of Impavido® yielded expected peaks for miltefosine (m/z 408.33 for the protonated parent ion and m/z 183.99 plus m/z 124.8 the fragment ions) that were absent in the Miltefos™ capsules. Furthermore, testing using an in vitro Leishmania donovani intracellular amastigote-macrophage model, yielded EC50 values of between 2.55 and 4.06 μg/mL and 3.02 to 5.92 μg/mL for extracts from the Impavido® capsules and the miltefosine standard, respectively. Lack of significant anti-leishmanial activity of Miltefos™ capsules was identified in this assay even at concentrations up to 100 μg/mL. Capsules of Miltefos™ were classified as falsified (absence of stated active pharmaceutical ingredient) by three methods-NMR and mass spectrometry analysis and bioassay. PMID:25897058

  14. Bioassay data and a retention-excretion model for systemic plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W.

    1984-05-01

    The estimation of systemic burdens from urinalyses has been the most common and useful method of quantifying occupational exposures to plutonium. Problems arise in using this technique, however, because of inadequate modeling of human retention, translocation, and excretion of this element. Present methods for estimating the systemic burden from urinalyses were derived to a large extent from patterns observed in the first few months after exposure, but there is now evidence that these same patterns do not persist over long periods. In this report we collect and discuss data needed for the interpretation of bioassay results for Pu. These data are used to develop a model that describes the movement, retention, and excretion of systemic Pu in the human body in terms of explicitly identified anatomical compartments. This model may be used in conjunction with existing models and/or case-specific information concerning the translocation of Pu from the respiratory or gastrointestinal tract or from wounds to the bloodstream. Attention is restricted to the behavior of Pu after it has gained access to the bloodstream. There remain significant uncertainties concerning some aspects of the movement of Pu, particularly its translocation from the liver. An attempt has been made to construct the model in such a way as to elucidate those areas needing further attention. 98 references, 18 figures, 16 tables.

  15. Bioassay development using early life stages of the marine macroalga, Ecklonia radiata

    Energy Technology Data Exchange (ETDEWEB)

    Bidwell, J.R.; Wheeler, K.D.; Roper, J. [Curtin Univ. of Technology, Perth (Australia); Burridge, T.R. [Victoria Univ. of Technology (Australia)

    1995-12-31

    A lack of standard toxicity test methods for species native to Australia has stimulated research to overcome this deficiency. In the present work, germination inhibition was utilized as an endpoint in 48h bioassays with the marine macroalga Ecklonia radiata. E radiata is often a dominant member of temperate subtidal communities in Australia and other parts of the southern hemisphere. The alga fills an ecological niche similar to that of Macrocystis pyrifera, the giant kelp which occurs in the northern hemisphere. In an adaptation of test methods used for M. pyrifera, release of E. radiata zoospores was induced in the laboratory. Settled spores were then exposed to toxicants for 48 h and germination success was determined by scoring the spores for the development of a germination tube. At 20 C, EC{sub 50} values ranging between 53.4 and 77.4 mg/L were generated in tests with hexavalent chromium (potassium chromate). The EC{sub 50} for copper (cupric chloride) was 0.53 mg/L. Sensitivity of E. radiata to metals such as copper may have significance toward assessing the environmental impacts of some antifoulant coatings used on seagoing vessels. In future studies, growth of zoospore germination tubes and comparative sensitivity of different E. radiata populations will be examined.

  16. Skeletal muscle afferent regulation of bioassayable growth hormone in the rat pituitary

    Science.gov (United States)

    Gosselink, K. L.; Grindeland, R. E.; Roy, R. R.; Zhong, H.; Bigbee, A. J.; Grossman, E. J.; Edgerton, V. R.

    1998-01-01

    There are forms of growth hormone (GH) in the plasma and pituitary of the rat and in the plasma of humans that are undetected by presently available immunoassays (iGH) but can be measured by bioassay (bGH). Although the regulation of iGH release is well documented, the mechanism(s) of bGH release is unclear. On the basis of changes in bGH and iGH secretion in rats that had been exposed to microgravity conditions, we hypothesized that neural afferents play a role in regulating the release of these hormones. To examine whether bGH secretion can be modulated by afferent input from skeletal muscle, the proximal or distal ends of severed hindlimb fast muscle nerves were stimulated ( approximately 2 times threshold) in anesthetized rats. Plasma bGH increased approximately 250%, and pituitary bGH decreased approximately 60% after proximal nerve trunk stimulation. The bGH response was independent of muscle mass or whether the muscles were flexors or extensors. Distal nerve stimulation had little or no effect on plasma or pituitary bGH. Plasma iGH concentrations were unchanged after proximal nerve stimulation. Although there may be multiple regulatory mechanisms of bGH, the present results demonstrate that the activation of low-threshold afferents from fast skeletal muscles can play a regulatory role in the release of bGH, but not iGH, from the pituitary in anesthetized rats.

  17. [Applicability of multivariate statistics for nutritional studies: bioassay rice weevil (Sitophilus oryzae L)].

    Science.gov (United States)

    Lugo Gonázlez, Dennis Alexander; Aguilar, Víctor Hugo; Casotto, Meris; Laurentin, Alexander; Gómez, Ana

    2013-09-01

    The principal component analysis (PCA), non-metric multidimensional scaling (MDS) and analysis of similarity (ANOSIM) are multivariate statistical techniques that graphically represent numerical measures of several factors and display multiple relationships that may exist between them. In this study, we evaluated the applicability of these techniques to analyze the nutritional quality of diet, using as model, the bioassay rice weevil. The diets tested were: corn starch, potato starch, 5% glucose, peas, starved and starved with water supply. The variables studied were: survival, weight change and body composition. The PCA and MDS showed positive relationships of survival and weight change with body fat and carbohydrate parameters. Fat and carbohydrates were greater in starches diets, similar to the positive control. The PCA showed differences between populations fed with different diets, whereas the MDS showed similarity between diets. Both studies defined a gradient of the nutritive value of diets in the x-axis. The ANOSIM indicate significant (p interaction of differents variables to measure the nutritional quality of diets. PMID:25362823

  18. Development of a bioassay using walleye (Sander vitreus) to assess the toxicity of oil sands sediments

    International Nuclear Information System (INIS)

    This study examined the effects of sediments from the Athabasca oil sands area on fish development and survival. Walleye (Sander vitreus) which inhabit the Athabasca River are exposed to natural sources of bitumen eroding from the McMurray formation. This study described the design and implementation of a daily-renewal bioassay to evaluate the potential effects of toxicants on walleye development. Eggs were collected and fertilized with milt from spawning wild walleye captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish. The walleye embryos were fed brine shrimp daily after hatching and the developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length between treatments. Organics concentrations in fish tissues and water were measured when possible. Fathead minnows and northern pikes will also be exposed to the same sediments in order to compare the relative sensitivity of the three species.

  19. Development of a bioassay to assess the toxicity of oil sands sediments to pike (Esox lucius)

    International Nuclear Information System (INIS)

    Pike (Esox lucius) are a commercially sought fish species that inhabit the Athabasca River, which flows through the Athabasca oil sands. The fish are exposed to natural sources of bitumen from the McMurray formation. This study was conducted to design and implement a daily-renewal bioassay to assess the toxicity of oil sands to this fish species and to obtain information regarding the development of pike exposed to bitumen. Eggs were collected and fertilized with milt from spawning wild pike captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish, approximately 15 days post-hatch. For the rest of the experiment, brine shrimp were fed to the walleye embryos every day after hatching. The developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length. The research findings indicated that pike is less sensitive than walleye and fathead minnow to the toxicity of oil sands sediments.

  20. Bioassay-Guided Isolation and Structural Modification of the Anti-TB Resorcinols from Ardisia gigantifolia.

    Science.gov (United States)

    Guan, Yi-Fu; Song, Xun; Qiu, Ming-Hua; Luo, Shi-Hong; Wang, Bao-Jie; Van Hung, Nguyen; Cuong, Nguyen M; Soejarto, Djaja Doel; Fong, Harry H S; Franzblau, Scott G; Li, Sheng-Hong; He, Zhen-Dan; Zhang, Hong-Jie

    2016-08-01

    Tuberculosis (TB) is a highly contagious disease mainly caused by Mycobacterium tuberculosis H37 RV . Antitubercular (anti-TB) bioassay-guided isolation of the CHCl3 extract of the leaves and stems of the medicinal plant Ardisia gigantifolia led to the isolation of two anti-TB 5-alkylresorcinols, 5-(8Z-heptadecenyl) resorcinol (1) and 5-(8Z-pentadecenyl) resorcinol (2). We further synthesized 15 derivatives based on these two natural products. These compounds (natural and synthetic) were evaluated for their anti-TB activity against Mycobacterium tuberculosis H37 RV . Resorcinols 1 and 2 exhibited anti-TB activity with MIC values at 34.4 and 79.2 μm in MABA assay, respectively, and 91.7 and 168.3 μm in LORA assay, respectively. Among these derivatives, compound 8 was found to show improved anti-TB activity than its synthetic precursor (2) with MIC values at 42.0 μm in MABA assay and 100.2 μm in LORA assay. The active compounds should be regarded as new hits for further study as a novel class of anti-TB agents. The distinct structure-activity correlations of the parent compound were elucidated based on these derivatives. PMID:26992112

  1. Use of Salmonella/microsome reversion bioassay for monitoring industrial wastewater treatment plants in Rajasthan, India.

    Science.gov (United States)

    Mathur, Nupur; Bhatnagar, Pradeep; Bakre, Prakash

    2012-05-01

    Salmonella/microsome reversion assay was used as a biological parameter for monitoring the toxicity of common effluent treatment plant (CETP), Mandia road industrial area, Pali catering to textile industrial areas in Pali, Rajasthan. The influent and effluent water of CETP, surface water (Bandi river) and underground water were tested using Ames bioassay. The results showed presence of mutagens in surface water of Bandi river and the underground water in Pali. Further, comparison of mutagenicity of CETP influent and effluent water revealed that the treatment method employed at this plant has failed to remove mutagenic substances present in Pali textile wastewater. The study also showed that Ames assay is an important tool in genotoxic studies because of its simplicity, sensitivity to genetic damage, speed, low cost of experimentation and small amount of sample required. Further Ames assay, as seen from the results of this study, can be used as a monitoring tool for not only CETPs but also for other water resources. The outcomes of the Ames assay demonstrated its performance as a sensitive, cost-effective and relatively rapid screening tool to assess the genotoxic potential of complex environmental samples. PMID:23029899

  2. Coupling SFE to uterotonic bioassay: an on-line approach to analysing medicinal plants.

    Science.gov (United States)

    Sewram, V; Raynor, M W; Raidoo, D M; Mulholland, D A

    1998-11-01

    Supercritical fluid extraction has been directly coupled on-line to a uterotonic bioassay, using guinea pig uterine smooth muscle in vitro. This technique was developed for the detection of uterotonic compounds present in medicinal plants used during pregnancy to induce or augment labour. The direct passage of CO2 into the muscle chamber led to adiabatic cooling of the physiological fluid and inhibition of muscle contraction. This was alleviated by the construction of a CO2 reduction interface together with the passage of carbogen which aided in the rapid displacement of excess CO2. The on-line system was evaluated with four plants (Clivia miniata (Lindl.) Regel, Ekebergia capensis Sparrm., Grewia occidentalis L. and Asclepias fruticosa L.) that are currently used during pregnancy by some black South African women. Extractions were performed with water modified supercritical CO2. Fractions of supercritical fluid extracts, obtained by sequentially increasing the pressure from 200 to 300 and 400 atm at constant temperature were transferred directly to the muscle chamber to identify the active fractions. The 400 atm extracts of C. miniata, A. fruticosa and E. capensis displayed maximum uterotonic activity while only the 300 atm extract of G. occidentalis induced uterine muscle contraction. This technique proved to be a safe and sensitive method for analyzing medicinal plants that contain uterotonic substances hence assisting in rapidly validating the uterotonic properties and detecting any toxic effects of these extracts. PMID:10096825

  3. A novel high-throughput irradiator for in vitro radiation sensitivity bioassays

    Science.gov (United States)

    Fowler, Tyler L.

    Given the emphasis on more personalized radiation therapy there is an ongoing and compelling need to develop high-throughput screening tools to further examine the biological effects of ionizing radiation on cells, tissues and organ systems in either the research or clinical setting. Conventional x-ray irradiators are designed to provide maximum versatility to radiobiology researchers, typically accommodating small animals, tissue or blood samples, and cellular applications. This added versatility often impedes the overall sensitivity and specificity of an experiment resulting in a trade-off between the number of absorbed doses (or dose rates) and biological endpoints that can be investigated in vitro in a reasonable amount of time. Therefore, modern irradiator designs are incompatible with current high-throughput bioassay technologies. Furthermore, important dosimetry and calibration characteristics (i.e. dose build-up region, beam attenuation, and beam scatter) of these irradiators are typically unknown to the end user, which can lead to significant deviation between delivered dose and intended dose to cells that adversely impact experimental results. Therefore, the overarching goal of this research is to design and develop a robust and fully automated high-throughput irradiator for in vitro radiation sensitivity investigations. Additionally, in vitro biological validation of this system was performed by assessing intracellular reactive oxygen species production, physical DNA double strand breaks, and activation of cellular DNA repair mechanisms. Finally, the high-throughput irradiator was used to investigate autophagic flux, a cellular adaptive response, as a potential biomarker of radiation sensitivity.

  4. Bioassay-Directed Isolation of Active Compounds with Antiyeast Activity from a Cassia fistula Seed Extract

    Directory of Open Access Journals (Sweden)

    Subramanion L. Jothy

    2011-09-01

    Full Text Available Background and objective: Cassia fistula L belongs to the family Leguminosae, and it is one of the most popular herbal products in tropical countries. C. fistula seeds have been used as a herbal medicine and have pharmacological activity which includes anti-bacterial, anti-fungal, and antioxidant properties. The goal of this study was to identify compounds from C. fistula seeds which are responsible for anti-Candida albicans activity using bioassay-directed isolation. Results: The preliminary phytochemical screening of the plant seed revealed the presence of anthraquinones, flavonoids, saponins, tannins and terpenoids. The isolation of active compounds was carried out in four steps: multiple extractions, fractionation using column chromatography and purification using preparative thin-layer chromatography (TLC and liquid chromatography/mass spectrometry (LC/MS. The structure of separated compounds was determined on the basis of mass spectrometry data. One compound was identified is roseanone. Conclusions: The MS analysis on the active fraction from seed extract of C. fistula confirmed the presence of roseanone with antiyeast activity.

  5. Isolation of antibacterial compounds from Quercus dilatata L. through bioassay guided fractionation

    Directory of Open Access Journals (Sweden)

    Jamil Maryam

    2012-05-01

    Full Text Available Abstract Background Four medicinal plants (Chrozophora hierosolymitana Spreng, Chrysanthemum leucanthemum L., Ephedra gerardiana Wall. ex Stapf, and Quercus dilatata L. used by indigenous healers to treat various infectious diseases were selected for the present study. The major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation. Methods Seven methanolic extracts of the four plants were screened to identify any antimicrobial agents present in them. The active crude plant extract was fractionated first by solvent partitioning and then by HPLC. Characterization of the active fractions was done by using spectrophotometer. Results All the seven methanolic extracts showed low antifungal activity, however, when these extracts were tested for antibacterial activity, significant activity was exhibited by two extracts. The extract of aerial parts of Q. dilatata was most active and therefore, was selected for further analysis. Initially fractionation was done by solvent-solvent partitioning and out of six partitioned fractions, ethanol fraction was selected on the basis of results of antibacterial activity and phytochemical analysis. Further, fractionation was carried out by RP- HPLC and purified active subfractions were characterized by comparing their absorption spectra with that of the known natural products isolated from the plants of Quercus genus. Discussion and conclusion The results suggest that this is the first report of the isolated antibacterial compounds from this genus.

  6. Comparative study on toxicity evaluation of anaerobically treated parboiled rice manufacturing wastewater through fish bioassay.

    Science.gov (United States)

    Giri, Dipti Ramesh; Singh, Ekta; Satyanarayan, Shanta

    2016-01-01

    Short term aquatic bioassay has been developed into a useful tool in water quality management. These tests give information on comparative toxicity of several compounds. The objective of this study was to evaluate the acute toxicity of raw and anaerobically treated effluents of the parboiled rice manufacturing industry. The acute toxicity test was carried out by using the fish Lebistes reticulatus under laboratory conditions. LC50 values for 24, 48, 72 and 96 hours ranged between 4.6 and 7.0% for the raw parboiled rice manufacturing wastewater. Two anaerobic fixed film fixed bed reactors and two different media matrices, i.e. UV stabilized Biopac media and Fugino spirals, were used for the treatment of parboiled rice mill wastewater. Effluents from these two reactors depicted LC50 values in the range of 68-88% and 62-78% for Biopac and Fugino spiral packed reactors, respectively. From the results, it is evident that anaerobically treated effluents from Biopac packed reactor is marginally better than Fugino spiral packed reactor. Results subjected to statistical evaluation depicted regression coefficient of more than 0.9 indicating good correlation between the mortality and effluent concentration. PMID:27120636

  7. Assessment of toxic potential of Cerrado fruit seeds using Artemia salina bioassay

    Directory of Open Access Journals (Sweden)

    Raíza Cavalcante Fonseca

    2013-06-01

    Full Text Available Artemia salina bioassay was used to assess toxicity of seeds and kernels of Brazilian fruits from cerrado (central high plains region and other inner regions of the country. Water extracts of the kernels were filtered and added to Artemia cultures containing ten individuals per mL. Dose - response curves were constructed, and LD50 values were calculated. Pure potassium cyanide standard was used to draw a calibration curve for comparison to detect the presence of cyanide in the samples tested. Extracts of the seeds of araticum, mangaba, cagaita, jatobá, and tucumã were found toxic to Artemia salina, and some of the dose - response curves were very similar in shape to those obtained with pure potassium cyanide standards, while the samples of baru, cajá-manga, siriguela, trauma, and veludo showed no toxicity at all. The Guignard test, specific for cyanide detection, showed negative results in all toxic samples, suggesting the presence of other toxic compounds rather than cyanide. The comparison of araticum dose - response curve with those of other annonaceous fruits suggests the presence acetogenins as the main toxic compounds in the seeds. These results could be useful to prevent poisoning by industrial derivatives of the fruits studied.

  8. Methotrexate intercalated layered double hydroxides with the mediation of surfactants: Mechanism exploration and bioassay study

    International Nuclear Information System (INIS)

    Methotrexatum intercalated layered double hydroxides (MTX/LDHs) hybrids were synthesized by the co-precipitation method and three kinds of nonionic surfactants with different hydrocarbon chain lengths were used. The resulting hybrids were then characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). XRD and FTIR investigations manifest the successful intercalation of MTX anions into the interlayer of LDHs. TEM graphs indicate that the morphology of the hybrids changes with the variation of the chain length of the surfactants, i.e., the particles synthesized using polyethylene glycol (PEG-7) present regular disc morphology with good monodispersity, while samples with the mediation of alkyl polyglycoside (APG-14) are heavily aggregated and samples with the addition of polyvinylpyrrolidone (PVP-10) exhibit irregular branches. Furthermore, the release and bioassay experiments show that monodisperse MTX/LDHs present good controlled-release and are more efficient in the suppression of the tumor cells. - Highlights: • Surfactants could be used to modify the dispersing state of MTX/LDHs hybrids. • Surfactants have great effect on the morphology of MTX/LDHs hybrids. • MTX/LDHs with good monodisperse degree are more efficient in the suppression of the tumor cells

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

    International Nuclear Information System (INIS)

    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 plutonium 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

  10. Bioassay data and a retention-excretion model for systemic plutonium

    International Nuclear Information System (INIS)

    The estimation of systemic burdens from urinalyses has been the most common and useful method of quantifying occupational exposures to plutonium. Problems arise in using this technique, however, because of inadequate modeling of human retention, translocation, and excretion of this element. Present methods for estimating the systemic burden from urinalyses were derived to a large extent from patterns observed in the first few months after exposure, but there is now evidence that these same patterns do not persist over long periods. In this report we collect and discuss data needed for the interpretation of bioassay results for Pu. These data are used to develop a model that describes the movement, retention, and excretion of systemic Pu in the human body in terms of explicitly identified anatomical compartments. This model may be used in conjunction with existing models and/or case-specific information concerning the translocation of Pu from the respiratory or gastrointestinal tract or from wounds to the bloodstream. Attention is restricted to the behavior of Pu after it has gained access to the bloodstream. There remain significant uncertainties concerning some aspects of the movement of Pu, particularly its translocation from the liver. An attempt has been made to construct the model in such a way as to elucidate those areas needing further attention. 98 references, 18 figures, 16 tables

  11. A rapid bioassay method for the determination of 90Sr in human urine sample

    International Nuclear Information System (INIS)

    A rapid bioassay method has been developed for the determination of 90Sr in human urine samples. The method is based on on-cartridge decolorisation of urine sample, separation of 90Y from 90Sr on an anion exchange resin column and by determination of 90Sr using a liquid scintillation analyser (LSA). Separation of 90Y from 90Sr was achieved through selective complexation of yttrium with phosphate and subsequent retention of the anionic yttrium phosphate species on anion exchange resin. A total recovery of 97 ± 2% was obtained for strontium with three washes. The minimum detectable activity for the method was 0.2 Bq or 40 Bq l-1. Measurement accuracy (relative bias, Br) and repeatability (relative precision, SB) of the method for the determination of 90Sr were found to be -1 and 4.7%, respectively. Excellent linearity (r2 > 0.999) was established over an activity range from 3.25 x 102 to 3.25 x 104 Bq l-1. The method was also found to be very robust (SB 90Sr is involved. (authors)

  12. Bioassay-Guided Isolation of Neuroprotective Compounds from Uncaria rhynchophylla against Beta-Amyloid-Induced Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Yan-Fang Xian

    2012-01-01

    Full Text Available Uncaria rhynchophylla is a component herb of many Chinese herbal formulae for the treatment of neurodegenerative diseases. Previous study in our laboratory has demonstrated that an ethanol extract of Uncaria rhynchophylla ameliorated cognitive deficits in a mouse model of Alzheimer’s disease induced by D-galactose. However, the active ingredients of Uncaria rhynchophylla responsible for the anti-Alzheimer’s disease activity have not been identified. This study aims to identify the active ingredients of Uncaria rhynchophylla by a bioassay-guided fractionation approach and explore the acting mechanism of these active ingredients by using a well-established cellular model of Alzheimer’s disease, beta-amyloid- (Aβ- induced neurotoxicity in PC12 cells. The results showed that six alkaloids, namely, corynoxine, corynoxine B, corynoxeine, isorhynchophylline, isocorynoxeine, and rhynchophylline were isolated from the extract of Uncaria rhynchophylla. Among them, rhynchophylline and isorhynchophylline significantly decreased Aβ-induced cell death, intracellular calcium overloading, and tau protein hyperphosphorylation in PC12 cells. These results suggest that rhynchophylline and isorhynchophylline are the major active ingredients responsible for the protective action of Uncaria rhynchophylla against Aβ-induced neuronal toxicity, and their neuroprotective effect may be mediated, at least in part, by inhibiting intracellular calcium overloading and tau protein hyperphosphorylation.

  13. Microflow injection potassium bioassay based on G-quadruplex DNAzyme-enhanced chemiluminescence.

    Science.gov (United States)

    Song, Lifang; Pan, Xiaoyan; Shen, Hong; Yu, Yaling

    2014-12-01

    By taking advantage of microflow injection chemiluminescence analysis, we developed a distinctive microfluidic bioassay method based on G-Quadruplex DNAzyme-enhanced chemiluminescence for the determination of K(+) in human serum. AGRO100, the G-rich oligonucleotide with high hemin binding affinity was primarily selected as a K(+) recognition element. In the presence of K(+), AGRO100 folded into G-quadruplex and bound hemin to form DNAzyme, which catalyzed the oxidation of luminol by H2 O2 to produce chemiluminescence. The intensity of chemiluminescence increased with the K(+) concentration. In the study, the DNAzyme showed both long-term stability and high catalytic activity; other common cations at their physiological concentration did not cause notable interference. With only 6.7 × 10(-13) mol of AGRO100 consumption per sample, a linear response of K(+) ranged from 1 to 300 µmol/L, the concentration detection limit 0.69 µmol/L (S/N = 3) and the absolute detection limit 1.38 × 10(-12) mol were obtained. The precision of 10 replicate measurements of 60 µmol/L K(+) was found to be 1.72% (relative standard deviation). The accuracy of the method was demonstrated by analyzing real human serum samples. PMID:24851824

  14. Towards the development of an embryotoxicity bioassay with terrestrial snails: Screening approach for cadmium and pesticides

    International Nuclear Information System (INIS)

    Currently no bioassays are available to assess the embryotoxicity of chemicals with terrestrial soil invertebrates. We therefore presented a new method for embryotoxicity testing with snail eggs: a relevant biological material that incubates in soil and that can be exposed to contaminants from leachates and soil solution. The effects of aqueous solutions of two herbicide formulations, Reglone (active ingredient (a.i.), diquat) and Roundup or its a.i., glyphosate, of a surfactant (Agral 90, a.i., nonylphenol polyethoxylates) and of cadmium (Cd) were studied. Endpoints were the hatching success and observations of embryo abnormalities after exposure. Roundup was found to be more toxic than its a.i. alone (EC50a.i. = 18 mg/l and about 1300 mg/l, respectively). Reglone (EC50a.i. = 0.72 mg/l) and Agral (EC50a.i. ∼ 50 mg/l) were also tested together, revealing that Reglone accounted for more than 99% of the mixture's toxicity. An antagonistic interaction between the two substances was found. For Cd (EC50 = 3.9 mg/l), a significant transfer from exposure medium to eggs was emphasized, particularly affecting the albumen. Abnormalities of embryogenesis in non-hatched embryos depended on the substance and the concentration considered.

  15. Preparative Purification and Bioassay of Bt Toxin from Cry1Ab Transgenic Rice

    Institute of Scientific and Technical Information of China (English)

    WU Jian-min; YE Qin-fu

    2004-01-01

    A method of extracting and purifying Cry1Ab protein(Bt toxin) from Cry1Ab transgenic rice was established. Most of the Bt toxin present in the tissue of Cry1Ab transgenic rice was extracted effectively with a solution of 50 mmol/LNa2CO3 and NaHCO3. The crude protein containing Bt toxin was obtained after the pretreatment of Cry1Ab transgenic rice with ultra-filtration, ammonium sulfate precipitation and centrifugation. The dialysed crude protein was futher separated on DEAE Sephadex A-50 columns and Sephadex G-150 columns. The protein bound on DEAE Sephadex A-50 gel was eluted with buffer solution B(10 mmol/L trisHCl buffer+1. 0 mmol/L EDTA, pH=8.0) mixed with 0. 1, 0. 3, 0. 5 and 0. 8 mol/L NaCl in a discontinuous gradient elution mode. The peak of the Bt toxin eluted from the columns was identified by ELISA and bioassayed with larvae of tobacco hornworms and silkworms. The purity and the bioactivity of the Bt toxin were determined by means of SDS-PAGE and larvicidal assay, respectively. The purity of the Bt toxin obtained by this method is high, and its insecticidal activity is retained after the toxin is purified.

  16. Effects of Jatropha curcas oil in Lactuca sativa root tip bioassays.

    Science.gov (United States)

    Andrade-Vieira, Larissa F; Botelho, Carolina M; Laviola, Bruno G; Palmieri, Marcel J; Praça-Fontes, Milene M

    2014-03-01

    Jatropha curcas L. (Euphorbiaceae) is important for biofuel production and as a feed ingredient for animal. However, the presence of phorbol esters in the oil and cake renders the seeds toxic. The toxicity of J. curcas oil is currently assessed by testing in animals, leading to their death. The identification of toxic and nontoxic improved varieties is important for the safe use of J. curcas seeds and byproducts to avoid their environmental toxicity. Hence, the aim of this study was to propose a short-term bioassay using a plant as a model to screen the toxicity of J. curcas oil without the need to sacrifice any animals. The toxicity of J. curcas oil was evident in germination, root elongation and chromosomal aberration tests in Lactuca sativa. It was demonstrated that J. curcas seeds contain natural compounds that exert phyto-, cyto- and genotoxic effects on lettuce, and that phorbol esters act as aneugenic agents, leading to the formation of sticky chromosomes and c-metaphase cells. In conclusion, the tests applied have shown reproducibility, which is important to verify the extent of detoxification and to determine toxic doses, thus reducing the numbers of animals that would be used for toxicity tests. PMID:24676174

  17. Glycan heterogeneity on gold nanoparticles increases lectin discrimination capacity in label-free multiplexed bioassays.

    Science.gov (United States)

    Otten, Lucienne; Vlachou, Denise; Richards, Sarah-Jane; Gibson, Matthew I

    2016-07-21

    The development of new analytical tools as point-of-care biosensors is crucial to combat the spread of infectious diseases, especially in the context of drug-resistant organisms, or to detect biological warfare agents. Glycan/lectin interactions drive a wide range of recognition and signal transduction processes within nature and are often the first site of adhesion/recognition during infection making them appealing targets for biosensors. Glycosylated gold nanoparticles have been developed that change colour from red to blue upon interaction with carbohydrate-binding proteins and may find use as biosensors, but are limited by the inherent promiscuity of some of these interactions. Here we mimic the natural heterogeneity of cell-surface glycans by displaying mixed monolayers of glycans on the surface of gold nanoparticles. These are then used in a multiplexed, label-free bioassay to create 'barcodes' which describe the lectin based on its binding profile. The increased information content encoded by using complex mixtures of a few sugars, rather than increased numbers of different sugars makes this approach both scalable and accessible. These nanoparticles show increased lectin identification power at a range of lectin concentrations, relative to single-channel sensors. It was also found that some information about the concentration of the lectins can be extracted, all from just a simple colour change, taking this technology closer to being a realistic biosensor. PMID:27181289

  18. Seed germination bioassay using maize seeds for phytoxicity evaluation of different composted materials

    International Nuclear Information System (INIS)

    In this paper we evaluated the phytotoxicity of different composts obtained by two different composting methods using seed germination bioassay. Seeds of Zea mays were sown in 1:5 extract of composts and these were compared with the control (100% distilled water) for each type of material. Composting of herbal pharmaceutical solid waste (HPSW) was carried out using both conventional bin and pit method. HPSW was mixed separately with poultry manure, cow-manure and goat manure in three different ratios. Uncomposted and composted HPSW were tested to study the Phytotoxicity on Zea mays seed germination, after composting increase in percent germination as well as germination index (GI) values were observed in all combinations regardless, composted by pit or bin method. The results clearly showed that composting reduced Phytotoxicity. The results showed that use of completely composted organic waste reduces the phytotoxicity and is better than the use of uncomposted waste. It was found that pit method was more suitable than bin method. Herbal waste with goat manure in 1:1 ratio was found to be the most effective combination as compared to other combinations here. Germination was 100% and the germination index was 1.4 whereas uncomposted HPSW showed the lowest percent germination i.e., 77% and germination index 52.31 respectively. (author)

  19. Bioassay procedures and health physics recommendations for a promethium-147 luminescent dial painting industry

    International Nuclear Information System (INIS)

    A study was conducted to determine the hazard to workers who were applying a radioactive luminescent paint to devices such as clock dials and hands, signs, etc. The paint used was a mixture of macrospheres containing 147Pm, ZnS, and a binder. It was applied by workers either manually or by machine. This study was designed to determine the radiological safety of these operations. The potential routes of intake of 147Pm by workers were identified as inhalation and ingestion. Air samples were taken at work stations; total and respirable-sized 147Pm particles were measured. Both were shown to be at a safe level. An animal inhalation study was conducted to determine deposition of respirable-sized 147Pm particles. Testing by a bioassay procedure developed specifically for this purpose revealed low levels of deposited activity in the respiratory systems of these animals. A health physics evaluation of the dial painting facility firm and operation revealed that extensive improvements in engineering controls and worker protection were needed. The health physics recommendations made, as a result, should be adopted as a minimum for maximization of long term benefits to both the employee and the employer

  20. Double incision wound healing bioassay using Hamelia patens from El Salvador.

    Science.gov (United States)

    Gomez-Beloz, Alfredo; Rucinski, James C; Balick, Michael J; Tipton, Camille

    2003-10-01

    Hamelia patens Jacq. (Rubiaceae) has received little attention in the laboratory for its wound healing ability even though it is commonly used as a treatment for wounds throughout Central America. A double incision wound healing bioassay was carried out with a crude extract of Hamelia patens collected from El Salvador. Animals were divided into three groups. Group I (n = 14) had the left incision treated with 5% (w/w) Hamelia patens and the contralateral side with petroleum jelly (PJ). Group II (n = 14) had the left incision treated with 10% (w/w) ointment and the contralateral side with petroleum jelly. Group III (n = 10) had the left incision treated with petroleum jelly and the contralateral side left untreated. Breaking strength of the incisions was measured on day 7 and day 12. For Groups I and II, there was no significant difference between treatment and control incisions at day 7. On day 12, there was a significant difference between the treated and control incisions for Groups I and II. There was no significant difference between petroleum jelly and untreated incisions for Group III on day 7 and day 12. Hamelia patens does increase breaking strength of wounds significantly more than the control group. Further wound healing studies of this plant are warranted. PMID:12963138

  1. Zebrafish bioassay-guided microfractionation identifies anticonvulsant steroid glycosides from the Philippine medicinal plant Solanum torvum.

    Science.gov (United States)

    Challal, Soura; Buenafe, Olivia E M; Queiroz, Emerson F; Maljevic, Snezana; Marcourt, Laurence; Bock, Merle; Kloeti, Werner; Dayrit, Fabian M; Harvey, Alan L; Lerche, Holger; Esguerra, Camila V; de Witte, Peter A M; Wolfender, Jean-Luc; Crawford, Alexander D

    2014-10-15

    Medicinal plants used for the treatment of epilepsy are potentially a valuable source of novel antiepileptic small molecules. To identify anticonvulsant secondary metabolites, we performed an in vivo, zebrafish-based screen of medicinal plants used in Southeast Asia for the treatment of seizures. Solanum torvum Sw. (Solanaceae) was identified as having significant anticonvulsant activity in zebrafish larvae with seizures induced by the GABAA antagonist pentylenetetrazol (PTZ). This finding correlates well with the ethnomedical use of this plant in the Philippines, where a water decoction of S. torvum leaves is used to treat epileptic seizures. HPLC microfractionation of the bioactive crude extract, in combination with the in vivo zebrafish seizure assay, enabled the rapid localization of several bioactive compounds that were partially identified online by UHPLC-TOF-MS as steroid glycosides. Targeted isolation of the active constituents from the methanolic extract enabled the complete de novo structure identification of the six main bioactive compounds that were also present in the traditional preparation. To partially mimic the in vivo metabolism of these triterpene glycosides, their common aglycone was generated by acid hydrolysis. The isolated molecules exhibited significant anticonvulsant activity in zebrafish seizure assays. These results underscore the potential of zebrafish bioassay-guided microfractionation to rapidly identify novel bioactive small molecules of natural origin. PMID:25127088

  2. ANTIMICROBIAL SCREENING AND BRINE SHRIMP LETHALITY BIOASSAY OF TINOSPORA CORDIFOLIA (FAM: MENISPERMACEAE

    Directory of Open Access Journals (Sweden)

    Mohammad Kaisarul Islam

    2011-12-01

    Full Text Available Tinospora cordifolia (Fam: Menispermaceae has been investigated for evaluation of the biological activities. The stem of Tinospora cordifolia were extracted with carbon tetrachloride, n-hexane and methanol were collected and afford 4.0 mg, 4.0 mg, and 4.0 mg, respectively for the test. The crude carbon tetrachloride, n-hexane, and methanol extract of the plant were subjected to antimicrobial screening against 15 microorganisms such as gram-positive, gram-negative, fungi by the disc diffusion method. But interestingly no fraction showed any inhibitory effect against all the microorganisms. In the brine shrimp lethality bioassay, carbon tetrachloride fraction showed high toxicity, where LC90 value was only 6.25 mg/ml. The methanol crude extract and n-hexane fraction showed LC50 of 1.563 and 6.05 mg/ml respectively with very narrow therapeutic index (LC90 of 43.0 mg/ml and 45.0 mg/ml respectively. This indicated that the cytotoxicity exhibited by the carbon tetra chloride, n-hexane, and methanol extract was very significant.

  3. Development of a bioassay using walleye (Sander vitreus) to assess the toxicity of oil sands sediments

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, D.; Yuan, H.; Tumber, V.; Parrott, J. [Environment Canada, Ottawa, ON (Canada); Raine, J. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2010-07-01

    This study examined the effects of sediments from the Athabasca oil sands area on fish development and survival. Walleye (Sander vitreus) which inhabit the Athabasca River are exposed to natural sources of bitumen eroding from the McMurray formation. This study described the design and implementation of a daily-renewal bioassay to evaluate the potential effects of toxicants on walleye development. Eggs were collected and fertilized with milt from spawning wild walleye captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish. The walleye embryos were fed brine shrimp daily after hatching and the developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length between treatments. Organics concentrations in fish tissues and water were measured when possible. Fathead minnows and northern pikes will also be exposed to the same sediments in order to compare the relative sensitivity of the three species.

  4. Development of a bioassay to assess the toxicity of oil sands sediments to pike (Esox lucius)

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, D.; Yuan, H.; Tumber, V.; Parrott, J. [Environment Canada, Ottawa, ON (Canada); Raine, J. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2010-07-01

    Pike (Esox lucius) are a commercially sought fish species that inhabit the Athabasca River, which flows through the Athabasca oil sands. The fish are exposed to natural sources of bitumen from the McMurray formation. This study was conducted to design and implement a daily-renewal bioassay to assess the toxicity of oil sands to this fish species and to obtain information regarding the development of pike exposed to bitumen. Eggs were collected and fertilized with milt from spawning wild pike captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish, approximately 15 days post-hatch. For the rest of the experiment, brine shrimp were fed to the walleye embryos every day after hatching. The developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length. The research findings indicated that pike is less sensitive than walleye and fathead minnow to the toxicity of oil sands sediments.

  5. Carcinogenic potential of some pesticides in a medium-term multi-organ bioassay in rats.

    Science.gov (United States)

    Hasegawa, R; Cabral, R; Hoshiya, T; Hakoi, K; Ogiso, T; Boonyaphiphat, P; Shirai, T; Ito, N

    1993-05-28

    The carcinogenic potential of 5 pesticides was analyzed using a medium-term multi-organ bioassay for carcinogenicity. Male F344 rats were initially treated with 3 known carcinogens (diethylnitrosamine, N-methyl-N-nitrosourea and N-bis(2-hydroxypropyl)nitrosamine) during a period of 4 weeks to induce neoplastic changes in a variety of organs, and then given one of 5 pesticides in the diet for a further 16 weeks. Neoplastic and pre-neoplastic lesions were found in the thyroid, kidney and urinary bladder with propineb, in the forestomach, kidney and thyroid with captan and folpet. The number of glutathione S-transferase placental-form-positive liver-cell foci was significantly increased in the captan- and phosmet-treated groups. Based on these findings, captan and propineb can be considered as carcinogens and carcinogenicity is suspected for folpet and phosmet. These results are in concordance with reported long-term carcinogenicity for captan, folpet and propineb. Daminozide was considered not to be carcinogenic. Thus, the present assay of 20 weeks' duration is useful for the prediction of potential carcinogens. PMID:8509224

  6. Joint use of laboratory bioassays and field-collected plants to evaluate toxicity and contaminant bioaccumulation

    International Nuclear Information System (INIS)

    Soil toxicity tests using lettuce (Latuca saliva) were conducted using soil samples collected as part of ecological risk assessments at two facilities in California. At some sites, terrestrial plants were collected in the field for chemical analysis. Ecological concerns focused on exposures to plants, phytophagous insects, and their secondary consumers, such as birds and small mammals. The toxicity tests were used to assess potential exposures to a variety of site-specific contaminants including organochlorine pesticides, PCBs, PAHs, petroleum hydrocarbons, heavy metals, and other inorganic substances. Site soils were combined with clean control soils to produce toxicity test soil dilutions containing 100%, 75%, 50%, 25%, and 0% site soils. Observations of seed germination and growth were made at day 0, 7, 14, 21 and 28. Toxicity test results were combined with soil chemical analytical results and physical characteristics to establish NOAELs and LOAELs. Bioaccumulation in the lettuce and field-collected plants was evaluated by comparing plant contaminant to soil contaminant concentrations. Allometric equations and sublethal toxicity data were used to predict potential effects on birds and small mammals. Whole-body contaminant concentrations in insects collected on some of the plants in the field were also considered in evaluating the potential for toxicity to insectivorous birds. The study indicated that contaminant uptake was occurring in the field-collected and bioassay plants but not the insects. Site factors in addition to soil contaminant concentration influenced the potential for plant toxicity and bioaccumulation

  7. Detection of sputum eicosanoids in cystic fibrosis and in normal saliva by bioassay and radioimmunoassay.

    Science.gov (United States)

    Zakrzewski, J T; Barnes, N C; Piper, P J; Costello, J F

    1987-01-01

    We have measured arachidonic acid (AA) metabolites, leukotrienes (LTs) and prostanoids (Ps), in sputum of patients with cystic fibrosis (CF) and in normal saliva using bioassay and radioimmunoassay (RIA). Almost three times as much LTB4 is present in CF extracts compared with slow reacting substances (SRSs). Leukotrienes were not detected in normal saliva. In CF sputum there is a three-fold increase in the level of the vasodilator prostanoid prostaglandin E2 (PGE2) and the stable metabolite of prostacyclin, 6-oxo PGF1 alpha compared with the vasoconstrictor prostaglandin F2 alpha (PGF2 alpha) and thromboxane B2 (TxB2), a hydrolysis product of thromboxane A2. Experiments with BW755c (25 micrograms ml-1, n = 3) indicated that the majority of this activity was not produced during the extraction procedure. The detection of LTs and Ps in sputum of CF patients shows that these substances are present at biologically active concentrations and may contribute to the pathophysiology of this disease. PMID:3028454

  8. Evaluation of acute ecotoxicity removal from industrial wastewater using a battery of rapid bioassays.

    Science.gov (United States)

    Dries, Jan; Daens, Dominique; Geuens, Luc; Blust, Ronny

    2014-01-01

    The present study compares conventional wastewater treatment technologies (coagulation-flocculation and activated sludge) and powdered activated carbon (PAC) treatment for the removal of acute ecotoxicity from wastewater generated by tank truck cleaning (TTC) processes. Ecotoxicity was assessed with a battery of four commercially available rapid biological toxicity testing systems, verified by the US Environmental Protection Agency. Chemical coagulation-flocculation of raw TTC wastewater had no impact on the inhibition of the bioluminescence by Vibrio fischeri (BioTox assay). Subsequent biological treatment with activated sludge without PAC resulted in BioTox inhibition-free effluent (activated sludge treatment without PAC produced an effluent that significantly inhibited (>50%) (i) the bioluminescence by Photobacterium leiognathi (ToxScreen³ test kit), (ii) the photosynthesis by the green algae Chlorella vulgaris (LuminoTox SAPS test kit), and (iii) the particle ingestion by the crustacean Thamnocephalus platyurus (Rapidtoxkit test kit). The lowest inhibition was measured after activated sludge treatment with the highest PAC dose (400 mg/L), demonstrating the effectiveness of PAC treatment for ecotoxicity removal from TTC wastewater. In conclusion, the combination of bioassays applied in the present study represents a promising test battery for rapid ecotoxicty assessment in wastewater treatment. PMID:25521143

  9. Strain typing of classical scrapie by transgenic mouse bioassay using protein misfolding cyclic amplification to replace primary passage.

    Directory of Open Access Journals (Sweden)

    Katy E Beck

    Full Text Available According to traditional murine bioassay methodology, prions must be serially passaged within a new host before a stable phenotype, and therefore a strain, can be assigned. Prions often transmit with difficulty from one species to another; a property termed the transmission barrier. Transgenic mouse lines that over express prion protein (PrP genes of different species can circumvent the transmission barrier but serial passages may still be required, particularly if unknown strains are encountered. Here we sought to investigate whether protein misfolding cyclic amplification (PMCA, an in-vitro method of PrP(Sc replication, could be used to replace serial passage of VRQ/VRQ classical scrapie isolates undergoing strain typing in ovine transgenic tg338 mice. Two classical scrapie field isolates that do not readily transmit to wild-type mice underwent bioassay in tg338 mice pre- and post- PMCA and the phenotype of disease in inoculated mice was compared. For one of the sources investigated, the PMCA product gave rise to the same disease phenotypes in tg338 mice as traditional bioassay, as indicated by lesion profile, IHC analysis and Western blot, whilst the second source produced phenotypic characteristics which were not identical with those that arose through traditional bioassay. These data show that differences in the efficiency of PMCA as a strain-typing tool may vary between ovine classical scrapie isolates and therefore suggest that the ability of PMCA to replace serial passage of classical scrapie in tg338 mice may depend on the strain present in the initial source.

  10. A systems approach to the management of arbuscular mycorrhiza: Bioassay and study of the impact of phosphorus supply

    OpenAIRE

    Kahiluoto, Helena

    2000-01-01

    The aim of this study was to find out whether utilization of arbuscular mycorrhiza (AM), in crop production in Nordic conditions, can be promoted through management of the cropping system. P fertilization was chosen as the pilot system to manage because it has a major effect on AM and because it is problematic from the viewpoint of sustainability. Our scant knowledge of AM functioning and its effects in the field is mainly due to the methodological problems of research. Therefore, a bioassay ...

  11. EVALUATION OF THROMBOLYTIC ACTIVITY AND BRINE SHRIMP LETHALITY BIOASSAY OF METHANOL EXTRACT OF STEMS OF TINOSPORA CRISPA

    OpenAIRE

    Md. Ariful Islam , Z. A. Mahmud*, S.M. Abdur Rahman , Md. Monirujjaman and Sajal K. Saha

    2013-01-01

    ABSTRACT: Tinospora crispa, a plant belonging to the family of Menispermaceae is a well-known traditional medicinal plant used in Bangladesh. The methanolic extracts of stems of the plant were evaluated for their thrombolytic and preliminary cytotoxic activities. The thrombolytic activity was evaluated using the in vitro clot lysis model while while the screening of cytotoxic activity was done using brine shrimp lethality bioassay. Different concentrations of stem extract were made in isotoni...

  12. Preliminary Characterization of Extracellular Allelochemicals of the Toxic Marine Dinoflagellate Alexandrium tamarense Using a Rhodomonas salina Bioassay

    OpenAIRE

    Allan Cembella; Bernd Krock; Haiyan Ma; Urban Tillmann

    2009-01-01

    Members of the marine dinoflagellate genus Alexandrium are known to exude allelochemicals, unrelated to well-known neurotoxins (PSP-toxins, spirolides), with negative effects on other phytoplankton and marine grazers. Physico/chemical characterization of extracellular lytic compounds of A. tamarense, quantified by Rhodomonas salina bioassay, showed that the lytic activity, and hence presumably the compounds were stable over wide ranges of temperatures and pH and were refractory to bacterial d...

  13. The intact immature rodent uterotrophic bioassay: possible effects on assay sensitivity of vomeronasal signals from male rodents and strain differences.

    OpenAIRE

    Ashby, John; Owens, William; Odum, Jenny; Tinwell, Helen

    2003-01-01

    The vomeronasal organ in rodents is an important social and sexual signaling pathway. We have investigated whether the housing of intact immature females in close proximity to mature males would interfere with the sensitivity of the immature rodent uterotrophic bioassay as the result of vomeronasal signals transmitted by male urinary proteins. The hypothesis was that the proximity of males might induce early puberty, thereby increasing mean uterine weight and reducing the responsiveness of th...

  14. Performance characteristics of high performance liquid chromatography, first order derivative UV spectrophotometry and bioassay for fluconazole determination in capsules

    OpenAIRE

    Josilene Chaves Ruela Corrêa; Camila Reichman; Hérida Regina Nunes Salgado; Cristina Duarte Vianna-Soares

    2012-01-01

    The bioassay, first order derivative UV spectrophotometry and chromatographic methods for assaying fluconazole capsules were compared. They have shown great advantages over the earlier published methods. Using the first order derivative, the UV spectrophotometry method does not suffer interference of excipients. Validation parameters such as linearity, precision, accuracy, limit of detection and limit of quantitation were determined. All methods were linear and reliable within acceptable limi...

  15. Evaluation of the Antiproliferative Activity of the Leaves from Arctium lappa by a Bioassay-Guided Fractionation

    OpenAIRE

    Celso Vataru Nakamura; João Carlos Palazzo de Mello; Tânia Ueda-Nakamura; Cláudio Roberto Novello; Ivânia Teresinha Albrecht Schuquel; Cássia Mônica Sakuragui; Heinrich Luftmann; Samara Requena Nocchi; Karine Zanoli; Rafael Eidi Yamamoto; Fabio Bahls Machado

    2012-01-01

    Arctium lappa L. (Asteraceae) is used in folk medicine around the World, and shows several kinds of biological activity, particularly in vitro antitumor activity in different cell lines. This study evaluated the antiproliferative activity of the crude extract, semipurified fractions, and isolated compounds from the leaves of A. lappa, through bioassay-guided testing in Caco-2 cells. The crude extract was obtained with a 50% hydroethanolic extract and then partitioned with hexane, ethyl acetat...

  16. Biomarkers and bioassays as alternative screening methods for the presence and effects of PCDD, PCDF and PCB

    International Nuclear Information System (INIS)

    Polyhalogenated aromatic hydrocarbons (PHAH) are wide spread, highly toxic, environmental contaminants. As such they pose risks for both humans and wildlife. For risk assessment purposes, concentrations are generally analyzed by HRGC-HR/LRMS. With the analytical data, mixture toxicity is calculated using the TEF concept. With this method only the defined congeners are taken into account and additivity for all congeners is assumed, whereas synergistic and antagonistic effects for several PCDD/F in combination with PCB have also been reported. To avoid these problems and high analytical costs, bioassays can be used for screening purposes. Cytochrome P 450 1 A 1 induction and vitamin A and thyroid hormone levels are shown to be useful markers for PHAH exposure. When bioassays based on cytochrome P 450 1 A 1 induction, in cultured cells, in multi-well culturing plates, are used, 2,3,7,8-TCDD detection limits <0.2 pg are possible. As such these bioassays are highly sensitive, cost effective and time saving. This application can be used as a pre-screening method to determine total ''dioxin'' content of environmental samples. (orig.)

  17. Assessment of the ecotoxicological risk of combined sewer overflows for an aquatic system using a coupled "substance and bioassay" approach.

    Science.gov (United States)

    Gooré Bi, Eustache; Monette, Frederic; Gasperi, Johnny; Perrodin, Yves

    2015-03-01

    Very few tools are available for assessing the impact of combined sewer overflows (CSOs) on receiving aquatic environments. The main goal of the study was to assess the ecotoxicological risk of CSOs for a surface aquatic ecosystem using a coupled "substance and bioassay" approach. Wastewater samples from the city of Longueuil, Canada CSO were collected for various rainfall events during one summer season and analyzed for a large panel of substances (n = 116). Four bioassays were also conducted on representative organisms of surface aquatic systems (Pimephales promelas, Ceriodaphnia dubia, Daphnia magna, and Oncorhynchus mykiss). The analytical data did not reveal any ecotoxicological risk for St. Lawrence River organisms, mainly due to strong effluent dilution. However, the substance approach showed that, because of their contribution to the ecotoxicological hazard posed by the effluent, total phosphorus (Ptot), aluminum (Al), total residual chlorine, chromium (Cr), copper (Cu), pyrene, ammonia (N-NH4 (+)), lead (Pb), and zinc (Zn) require more targeted monitoring. While chronic ecotoxicity tests revealed a potential impact of CSO discharges on P. promelas and C. dubia, acute toxicity tests did not show any effect on D. magna or O. mykiss, thus underscoring the importance of chronic toxicity tests as part of efforts aimed at characterizing effluent toxicity. Ultimately, the study leads to the conclusion that the coupled "substance and bioassay" approach is a reliable and robust method for assessing the ecotoxicological risk associated with complex discharges such as CSOs. PMID:25315929

  18. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    International Nuclear Information System (INIS)

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE

  19. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    An, Youn-Joo [Department of Environmental Science, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)]. E-mail: anyjoo@konkuk.ac.kr

    2005-03-01

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE.

  20. Detection of estrogen receptor endocrine disruptor potency of commonly used organochlorine pesticides using the LUMI-CELL ER bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, J.D.; Chu, A.C.; Clark, G.C. [Xenobiotic Detection Systems, Inc., Durham, NC (United States); Chu, M.D. [Alta Analytical Perspectives, Wilmington, NC (United States); Denison, M.S. [Dept. of Environmental Toxicology, Univ. of California, Davis, CA (United States)

    2004-09-15

    In order to detect the endocrine disrupting potency of organochlorine pesticides and other compounds, BG-1 (human ovarian carcinoma) cells containing a stably transfected estrogenresponsive luciferase reporter gene plasmid (BG1Luc4E2), was used. This cell line, termed the LUMI-CELL trademark ER estrogenic cell bioassay system, responds in a time-, dose dependent- and chemical-specific manner with the induction of luciferase gene expression in response to exposure to estrogen (but not other steroid hormones) and estrogenic chemicals in a high-throughput screening (HTPS) format6. Here we describe studies in which the LUMI-CELL trademark ER estrogenic cell bioassay system was used for high throughput screening (HTPS) analysis of the estrogenic disrupting potency of several commonly used pesticides and organochlorines: p,p'DDT; p,p'-DDE; DDD; {alpha}a-chlordane; {psi}-chlordane; Kepone; Methoxychlor; Vinclozolin; Fenarimol; 2,4,5-Trichlorophenoxyacetic Acid; and Dieldrin. Our results demonstrate the utility of XDS's LUMI-CELL trademark ER bioassay HTPS system for screening chemicals for estrogenic activity.

  1. Biological testing of sediment for the Olympia Harbor Navigation Improvement Project, 1988: Geoduck, amphipod, and echinoderm bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Ward, J.A.; Word, J.Q.; Antrim, L.D.

    1989-05-01

    The Olympia Harbor Navigation Improvement Project requires the dredging of approximately 330,000 cubic yards (cy) of sediment from the harbor entrance channel and 205,185 cy from the turning basin. Puget Sound Dredged Disposal Analysis (PSDDA) partial characterization studies were used to plan a full sediment characterization in which chemical analyses and biological testing of sediments evaluated the suitability of the dredged material for unconfined, open-water disposal. The US Army Corps of Engineers (COE), Seattle District, contracted with NOAA/NMFS, Environmental Conservation Division, to perform the chemical analysis and Microtox bioassay tests, and with the Battelle/Marine Sciences Laboratory (MSL) in Sequim to perform flow-through solid-phase bioassays utilizing juvenile (8 to 10 mm) geoduck clams, Panopea generosa, and static solid phase bioassays using the phoxocephalid amphipod, Rhepoxynius abronius, developing embryos and gametes of the purple sea urchin, Strongylocentrotus purpuratus, and the larvae of the Pacific oyster Crassostrea gigas. When the results of the biological tests were evaluated under PSDDA guidelines, it was found that all the tested sediment treatments from Olympia Harbor are suitable for unconfined open-water disposal. 14 refs., 12 figs., 3 tabs.

  2. Detection of marine microalgal biotoxins using bioassays based on functional expression of tunicate xenobiotic receptors in yeast.

    Science.gov (United States)

    Richter, Ingrid; Fidler, Andrew E

    2015-03-01

    Marine microalgae can produce biotoxins that cause widespread poisoning in marine ecosystems and may also affect human health. While established microalgal biotoxins are detectable using chemical methods, a need remains for robust, inexpensive bioassays. Ligand-binding domains (LBDs) from a tunicate nuclear receptor, VDR/PXRα, which is orthologous to both the vertebrate pregnane X receptor (PXR) and the vitamin D receptor (VDR), can be activated by microalgal biotoxins when expressed in mammalian cell lines. Building on this observation, we developed a generic recombinant yeast bioassay platform that expresses chimeric proteins containing tunicate VDR/PXRα LBDs which mediate ligand-dependent transcription of a reporter gene (lacZ) encoding an easily assayed enzyme (β-galactosidase). Recombinant yeast strains expressing VDR/PXRα LBDs from two tunicate species, Ciona intestinalis and Botryllus schlosseri, were exposed to both synthetic and natural toxins. Structurally simple synthetic chemicals (n-butyl-p-aminobenzoate, carbamazepine, p-aminobenzoic acid, and bisphenol-A) generated EC50 values in the μM range, while more structurally complex marine biotoxins (okadaic acid, pectenotoxin-11, and portimine) activated the assays in the nM range. Given the large number of tunicate species, we propose that tunicate VDR/PXR LBDs may be used as 'sensor elements' in similar yeast-based high-throughput bioassays for detection of established microalgal biotoxins and uncharacterised marine bioactive compounds. PMID:25549942

  3. Plant bioassays to assess toxicity of textile sludge compost Bioensaios vegetais na avaliação da toxidade do composto de lodo têxtil

    OpenAIRE

    Ademir Sérgio Ferreira de Araújo; Regina Teresa Rosim Monteiro

    2005-01-01

    Composting of industrial wastes is increasing because of recycling requirements set on organic wastes. The evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. The toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. Compost samples were mixed with water (seed germination bioassay) or nutrient solution (plant growth b...

  4. Cell bioassay for paralytic shellfish poisoning (PSP): comparison with postcolumn derivatization liquid chromatographic analysis and application to the monitoring of PSP in shellfish.

    Science.gov (United States)

    Hayashi, Rumiko; Saito, Hiroshi; Okumura, Masanao; Kondo, Fumio

    2006-01-25

    We performed a neuroblastoma cell (Neuro2a) culture assay modified slightly from a method reported previously to provide a simple and sensitive evaluation of paralytic shellfish poisoning (PSP) toxicity in shellfish. The cell bioassay was just as sensitive for C-toxins as for gonyautoxins. The sensitivity of our cell bioassay was 4 times that of the current standard mouse bioassay. Using the cell bioassay, we evaluated PSP toxicity in 361 shellfish samples collected from Mikawa Bay and Ise Bay, Aichi Prefecture, Japan, from April 1999-March 2002. The results were compared with those obtained in a postcolumn derivatization liquid chromatographic analysis. PSP toxins were detected in 236/361 samples by both assays, and there was a fairly good correlation (r = 0.9001, n = 236, p < 0.001) between the results from the two assays. We applied this cell bioassay when short-necked clams in the bay turned poisonous in 2001. The chronological changes in PSP toxicity in the short-necked clams were analyzed and compared with those of the cell density of poisonous plankton (Alexandrium tamarense) occurring in the bay. The PSP toxicity in shellfish peaked 2 weeks after the cell density reached a maximum. We recommend using the cell bioassay for routine monitoring of PSP toxicity in shellfish living in natural marine environments. PMID:16417278

  5. Use of a chemically induced-colon carcinogenesis-prone Apc-mutant rat in a chemotherapeutic bioassay

    International Nuclear Information System (INIS)

    Chemotherapeutic bioassay for colorectal cancer (CRC) with a rat model bearing chemically-induced CRCs plays an important role in the development of new anti-tumor drugs and regimens. Although several protocols to induce CRCs have been developed, the incidence and number of CRCs are not much enough for the efficient bioassay. Recently, we established the very efficient system to induce CRCs with a chemically induced-colon carcinogenesis-prone Apc-mutant rat, Kyoto Apc Delta (KAD) rat. Here, we applied the KAD rat to the chemotherapeutic bioassay for CRC and showed the utility of the KAD rat. The KAD rat has been developed by the ENU mutagenesis and carries a homozygous nonsense mutation in the Apc gene (S2523X). Male KAD rats were given a single subcutaneous injection of AOM (20 mg/kg body weight) at 5 weeks of age. Starting at 1 week after the AOM injection, they were given 2% DSS in drinking water for 7 days. Tumor-bearing KAD rats were divided into experimental and control groups on the basis of the number of tumors observed by endoscopy at week 8. The 5-fluorouracil (5-FU) was administrated intravenously a dose of 50 or 75 mg/kg weekly at week 9, 10, and 11. After one-week interval, the 5-FU was given again at week 13, 14, and 15. At week 16, animals were sacrificed and tumor number and volume were measured macroscopically and microscopically. In total 48 tumors were observed in 27 KAD rats with a 100% incidence at week 8. The maximum tolerated dose for the KAD rat was 50 mg/kg of 5-FU. Macroscopically, the number or volume of tumors in the 5-FU treated rats was not significantly different from the control. Microscopically, the number of adenocarcinoma in the 5-FU treated rats was not significantly different (p < 0.02) from that of the control. However, the volume of adenocarcinomas was significantly lower than in the control. Anticancer effect of the 5-FU could be obtained only after the 16 weeks of experimental period. The use of the AOM/DSS-treated tumor

  6. Chemically induced immunotoxicity in a medium-term multiorgan bioassay for carcinogenesis with Wistar rats

    International Nuclear Information System (INIS)

    A variety of chemicals can adversely affect the immune system and influence tumor development. The modifying potential of chemical carcinogens on the lymphoid organs and cytokine production of rats submitted to a medium-term initiation-promotion bioassay for carcinogenesis was investigated. Male Wistar rats were sequentially initiated with N-nitrosodiethylamine (DEN), N-methyl-N-nitrosourea (MNU), N-butyl-N-(4hydroxybutyl)nitrosamine (BBN), dihydroxy-di-n-propylnitrosamine (DHPN), and 1,2-dimethylhydrazine (DMH) during 4 weeks. Two initiated groups received phenobarbital (PB) or 2-acetylaminofluorene (2-AAF) for 25 weeks and two noninitiated groups received only PB or 2-AAF. A nontreated group was used as control. Lymphohematopoietic organs, liver, kidneys, lung, intestines, and Zymbal's gland were removed for histological analysis. Interleukin (IL)-2, IL-12, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-10, and transforming growth factor beta1 (TGF-β1) levels were determined by ELISA in spleen cell culture supernatants. At the fourth week, exposure to the initiating carcinogens resulted in cell depletion of the thymus, spleen and bone marrow, and impairment of IL-2, IL-12, and IFN-γ production. However, at the 30th week, no important alterations were observed both in lymphoid organs and cytokine production in the different groups. The results indicate that the initiating carcinogens used in the present protocol exert toxic effects on the lymphoid organs and affect the production of cytokines at the initiation step of carcinogenesis. This early and reversible depression of the immune surveillance may contribute to the survival of initiated cells facilitating the development of future neoplasia

  7. Bioassay analysis of efficacy of phytoremediation in decontamination of coal mine effluent.

    Science.gov (United States)

    Bharti, Sandhya; Banerjee, Tarun Kumar

    2013-06-01

    Phytoremediation efficacy of Lemna minor and Azolla pinnata in decontaminating metals from coal mine effluent (CME) was analyzed using bioassays. Catfish Heteropneustes fossilis were exposed to both the phytoremediated CMEs for the metal bioaccumulation analysis and biochemical alteration in seven vital tissues. Gross concentration of metals accumulated in liver, kidneys, air breathing organs (ABO), skin and muscle were greater in fish exposed to A. pinnata remediated CME (AP-CME) than those exposed to L. minor remediated CME (LP-CME). Total protein concentrations of all the tissues were greater in fish exposed to LP-CME than to AP-CME. Glycogen concentrations were greater in muscle, brain, ABO and skin of LP-CME exposed fish. In remaining tissues (liver, kidneys and gills) concentrations of glycogen were more in AP-CME exposed ones. Total lipid and total DNA concentrations were greater in most of the tissues of fish exposed to LP-CME than to AP-CME. The total RNA concentrations were elevated only in muscle, liver, kidneys and brain of LP-CME exposed fish; in rest of the tissues (gills, ABO and skin) it was greater in AP-CME exposed fish. The values of condition factor (K) and organosomatic index (OSI) of fish exposed to LP-CME and AP-CME were insignificant to those of wild fish. However, the improvements in the biomolecules concentration of tissues of fish exposed to either of the phytoremediated effluent were not equivalent to their concentration in the wild fish. Thus, decontamination of CME by either of these macrophytes was not complete and prolonged exposure of even phytoremediated CMEs exerts deleterious effects on the fish. PMID:23566881

  8. Thioglucose-stabilized gold nanoparticles as a novel platform for colorimetric bioassay based on nanoparticle aggregation.

    Science.gov (United States)

    Watanabe, Shigeru; Yoshida, Kazuma; Shinkawa, Keitarou; Kumagawa, Daisuke; Seguchi, Hideki

    2010-12-01

    Gold nanoparticles stabilized with thioglucose (TGlu-AuNPs), which have carboxyl groups on the particle surface as anchoring sites for covalent immobilization of biomolecules, were prepared by the chemical reduction of HAuCl4 using 1-thio-β-D-glucose as a reducing and stabilizing agent, and their application to colorimetric bioassay was demonstrated using the carbohydrate-lectin system. p-Aminophenyl α-D-mannose (Man-NH2) was covalently attached by a conventional method to the activated carboxyl groups on the TGlu-AuNPs. On addition of Con A to the Man-AuNPs, multiple binding events occurred between Con A and the mannoses immobilized on the particle surface. This Con A-induced aggregation resulted in a significant red shift in local surface plasmon resonance. The binding isotherm showed a sigmoidal curve, indicating cooperativity in the binding of Con A and the Man-AuNPs. In addition, Hill plots showed two nonequivalent binding modes, with the Kd values for high- and low-affinity binding of 11.3 and 66.5 pM, respectively, which was significantly lower than that for methyl-α-D-mannose binding to Con A. The enhanced binding affinity between Man-AuNPs and Con A involves the cluster effect of the carbohydrate groups on the AuNPs. A linear correlation curve was obtained in the range 10-100 nM (R2=0.983). The limit of detection (LOD) for Con A was 9.0 nM in aqueous buffer, which is comparable to that of other conventional methods such as ELISA. PMID:20801619

  9. Calibration of in vitro bioassay methodology for determination “1”3”1I urine

    International Nuclear Information System (INIS)

    The use of unsealed radioactive sources in institutions practicing nuclear medicine poses a significant risk of internal exposure of workers. In this context, handling of “1”3”1I plays an important role in relation to other radionuclides due to its wide application, particularly in medical diagnosis and therapy of diseases related to the thyroid gland. Given the increasing number of services using “1”3”1I in their examination protocols, the probability of accidental incorporation of this radionuclide has increased. The present study aimed to implement methodologies for in vitro bioassay at the Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN), Recife, Brazil, for internal monitoring of individuals occupationally exposed to “1”3”1I. For in vitro system calibration, a coaxial HPGe detector model GC1018 and a standard “1”3”3Ba source were used. Upon obtaining the calibration factor, it was possible to determine the minimum detectable activities (MDA) for the system by using direct measurements of distilled water simulating urine (in vitro). Then, by using the biokinetic models provided by the International Commission on Radiological Protection, edited with the AIDE software version 6.0, it was possible to estimate the Minimum Detectable Effective Dose (MDED). MDED values obtained were compared to the record level of 1 mSv recommended by the International Atomic Energy Agency in the urine compartment 24 h. The values found were lower than the record level of 1 mSv in all simulated incorporation scenarios: inhalation of vapor and particles with AMAD of 1 μ and 5 μ, type F compound, and ingestion. The results of this work show that the implemented technique is suitable for conducting internal monitoring of workers to “1”3”1I. It is intended to continue the work aiming the monitoring of occupationally exposed individuals from Nuclear Medicine Services in Recife, Brazil. (authors)

  10. Occupational monitoring programme of uranium concentrate unit in Caetite, Brazil: Bioassay programme

    International Nuclear Information System (INIS)

    Full text: The principal aim of the bioassay monitoring program in the Uranium Concentrate Unity in Caetite is the maintenance of acceptable safe and satisfactory working conditions, according to national and international norms. Specifically, the objective is to interpret measurements in terms of intake of uranium and committed effective dose, so that the results can be used to demonstrate compliance with the system of dose limitation and, mainly, the optimization of radiation protection. The employed technique is the measurement of uranium in excreta from workers in mine, crushing and uranium concentrate production areas. The present work also aims at reporting the analysis results of incorporation of natural uranium, from bio analyses of urine on routine for class y insoluble uranium (ore dust) and operational monitoring for class D solubility uranium (Ammonium Diuranate), and committed effective dose estimates of workers occupationally exposed. In conclusion, workers from the mining and crushing areas should be monitored by the routine program; urine and feces samples should be analysed by mass spectrometry, with ICPMS. The operational monitoring program should be carried out in workers from the uranium concentrate production area; urine and feces samples may be analysed by less expensive techniques. For routine monitoring, based on the Mann-whitney Test, data from baseline monitoring were considered statistically equal to data from routine monitoring. Only three of out 24 workers showed results higher than the baseline, generating calculation of committed effective dose. However, none of them reached values bigger than those allowed to workers in Brazilian regulations. For operational monitoring the same behavior described above is repeated, with baseline data considered statistically equal to operational monitoring, and only three out of 18 workers showed higher values in the operational monitoring. Once again values were within the limits established in

  11. Interlaboratory comparisons of receptor binding assay with mouse bioassay as screening method for shellfish toxicity

    International Nuclear Information System (INIS)

    The Receptor-binding Assay (RBA) is an isotope-based technique using tritium-labeled saxitoxin (STX) as a tracer. Its response is based on the competition between the labeled and unlabeled saxitoxin to specifically interact with its receptor, sodium (Na+) channel. RBA is locally established at PNRI and now being routinely used for research purposes. RBA results were compared with the standard mouse bioassay method (MBA) as a part of screening program for shellfish toxins. The Microplate RBA is shown to have a sensitivity of 0.40 μg Saxitoxin equiv/100 g shellfish meat. A good agreement at low levels (40-50 μg Saxitoxin equiv/100 g shellfish meat) in the preliminary assays was obtained between the methods. With this, RBA method shows potential in the routine monitoring of shellfish PSP toxicity. Assay interlaboratory comparisons among Asia-Pacific Region laboratories were also performed. The RBA, in microplate and traditional formats, shown to have a sensitivity of 0.30 and 0.25 μg STX equiv/100 g shellfish meat respectively. The inter-and intra-assay variation for RBA is within 5-11%, which met the <30% criterion. The quality control check is within 6.3%, which validates day-to-day analyses. The results are highly comparable and consistent with expected values, with an RSD value <20%, as expected for good variability among the samples. RBA results were highly correlated and exhibited close quantitative agreement with MBA. It provides a reliable means of rapidly assessing PSP toxicity in laboratory and field samples. Thus, RBA can be effective screening tool in responding to suspected cases of PSP intoxication. (author)

  12. Facile synthesis of methotrexate intercalated layered double hydroxides: particle control, structure and bioassay explore.

    Science.gov (United States)

    Tian, De-Ying; Liu, Zhen-Lei; Li, Shu-Ping; Li, Xiao-Dong

    2014-12-01

    To study the influence of particle size on drug efficacy and other properties, a series of methotrexate intercalated layered double hydroxides (MTX/LDHs) were synthesized through the traditional coprecipitation method, using a mixture of water and polyethylene glycol (PEG-400) as the solvent. To adjust the particle size of MTX/LDHs, the dropping way, the volume ratio of water to PEG-400 and different hydrothermal treatment time changed accordingly, and the results indicate that the particle size can be controlled between 90 and 140 nm. Elemental C/H/N and inductive coupled plasma (ICP) analysis indicated that different synthesis conditions almost have no effect on the compositions of the nanohybrids. X-ray diffraction (XRD) patterns manifested the successful intercalation of MTX anions into the LDH interlayers, and it's also found out that different volume ratios of water to PEG-400 and variable dropping way can affect the crystallinity of the final samples, i.e., the volume ratio of 3:1 and pH decreasing are proved to be optimum conditions. Furthermore, both antiparallel monolayer and bilayers adopting different orientations are suggested for four samples from XRD results. Fourier transform infrared spectroscopy (FTIR) investigations proved the coexistence of CO3(2-) and MTX anions in the interlayer of the nanohybrids. MTX/LDH particles exhibited hexagonal platelet morphology with round corner and different dropping ways can affect the morphology greatly. Moreover, a DSC study indicated that longer time treatment can weaken the bond between the MTX anions and LDH layers. The kinetic release profiles told us that larger MTX/LDH particles have enhanced the ability of LDH layers to protect interlayer molecules. At last, the bioassay study indicated that the nanohybrids with larger diameters have higher tumor suppression efficiency. PMID:25491832

  13. Properties of coatings on RFID p-Chips that support plasmonic fluorescence enhancement in bioassays

    Science.gov (United States)

    Rich, Ryan; Li, Ji; Fudala, Rafal; Gryczynski, Zygmunt; Gryczynski, Ignacy; Mandecki, Wlodek

    2012-01-01

    Microtransponders (RFID p-Chips) derivatized with silver island film (SIF) have previously seen success as a platform for the quantification of low-abundance biomolecules in nucleic acid-based assays and immunoassays. In this study, we further characterized the morphology of the SIF as well as the polymer matrix enveloping it by scanning electron microscopy (SEM). The polymer was a two-layer silane-based matrix engulfing the p-Chip and SIF. Through a series of SEM and confocal fluorescence microscopy experiments we found the depth of the polymer matrix to be 1–2 µm. The radiative effects of the SIF/polymer layer were assessed by fluorescence lifetime imaging (FLIM) of p-Chips coated with the polymer to which a fluorophore (Alexa Fluor 555) was conjugated. FLIM images showed an 8.7-fold increase in fluorescence intensity and an increased rate of radiative decay, the latter of which is associated with improved photostability and both of which are linked to plasmonic enhancement by the SIF. Plasmonic enhancement was found to extend uniformly across the p-Chip and, interestingly, to a depth of about 1.2 µm. The substantial depth of enhancement suggests that the SIF/polymer layer constitutes a three-dimensional matrix that is accessible to solvent and small molecules such as fluorescent dyes. Finally, we confirmed that no surface-enhanced Raman scattering (SERS) is seen from the SIF/polymer combination. The analysis provides a possible mechanism by which the SIF/polymer-coated p-Chips allow a highly sensitive immunoassay and, as a result, leads to an improved bioassay platform. PMID:22960796

  14. Bioassay alpha spectrometry: energy resolution as a function of sample source preparation and counting geometry

    International Nuclear Information System (INIS)

    Alpha particle counting is based on the response of an electronic counting system to an incident alpha particle. Alpha spectrometry is used in our employee surveillance bioassay program to measure the concentration of isotopes of Am, Pu and U contained on sample source preparations. Nuclides of Am, Pu and U are separated from the sample matrix by anion exchange and are electroplated on a stainless steel disc. The plated source diameter is 12.7 mm. A tracer is added to the sample before anion exchange as a quality control procedure to provide a measure of chemical yield. Tracer alpha-particle emissions are recorded in a preassigned calibrated area of the energy spectrum and chemical recovery is calculated by the ratio of tracer counts per second divided by the tracer activity in becquerels (Bq). Percent tracer recovery may also be calculated by introducing the average counting efficiency factor in the denominator. Tracer yield is then used to provide a reliable estimate of the sample's analyte counts that are recorded in other preassigned energy dependent areas of the spectrum. The tracer spectrum in the presence or absence of other nuclides also provides evidence of the performance characteristics of the alpha spectrometer, for example, chamber vacuum and electronics. Electroplated samples are counted in any one of 96 detectors. The backgrounds of these detectors are maintained at less than 3 counts per 70,000 s over a 190 keV energy window to provide a limit of detection of less than 0.37 mBq per sample at the 95% confidence level. In this paper, resolution of the photopeak is shown to be a function of the source to detector distance and a function of degraded alpha energies due to Fe or other extraneous materials on the plated surface

  15. Chip-Scale Bioassays Based on Surface-Enhanced Raman Scattering: Fundamentals and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hye-Young Park

    2005-12-17

    This work explores the development and application of chip-scale bioassays based on surface-enhanced Raman scattering (SERS) for high throughput and high sensitivity analysis of biomolecules. The size effect of gold nanoparticles on the intensity of SERS is first presented. A sandwich immunoassay was performed using Raman-labeled immunogold nanoparticles with various sizes. The SERS responses were correlated to particle densities, which were obtained by atomic force microscopy (AFM). The response of individual particles was also investigated using Raman-microscope and an array of gold islands on a silicon substrate. The location and the size of individual particles were mapped using AFM. The next study describes a low-level detection of Escherichia coli 0157:H7 and simulants of biological warfare agents in a sandwich immunoassay format using SERS labels, which have been termed Extrinsic Raman labels (ERLs). A new ERL scheme based on a mixed monolayer is also introduced. The mixed monolayer ERLs were created by covering the gold nanoparticles with a mixture of two thiolates, one thiolate for covalently binding antibody to the particle and the other thiolate for producing a strong Raman signal. An assay platform based on mixed self-assembled monolayers (SAMs) on gold is then presented. The mixed SAMs were prepared from dithiobis(succinimidyl undecanoate) (DSU) to covalently bind antibodies on gold substrate and oligo(ethylene glycol)-terminated thiol to prevent nonspecific adsorption of antibodies. After the mixed SAMs surfaces, formed from various mole fraction of DSU were incubated with antibodies, AFM was used to image individual antibodies on the surface. The final study presents a collaborative work on the single molecule adsorption of YOYO-I labeled {lambda}-DNA at compositionally patterned SAMs using total internal reflection fluorescence microscopy. The role of solution pH, {lambda}-DNA concentration, and domain size was investigated. This work also revealed

  16. Screening for unicellular algae as possible bioassay organisms for monitoring marine water samples.

    Science.gov (United States)

    Millán de Kuhn, Rosmary; Streb, Christine; Breiter, Roman; Richter, Peter; Neesse, Thomas; Häder, Donat-Peter

    2006-08-01

    ECOTOX is an automatic early warning system to monitor potential pollution of freshwater, municipal or industrial waste waters or aquatic ecosystems. It is based on a real time image analysis of the motility and orientation parameters of the unicellular, photosynthetic flagellate Euglena gracilis. In order to widen the use of the device to marine habitats and saline waters nine marine flagellates were evaluated as putative bioassay organisms, viz. Dunaliella salina, Dunaliella viridis, Dunaliella bardawil, Prorocentrum minimum Kattegat, P. minimum Lissabon, Tetraselmis suecica, Heterocapsa triquetra, Gyrodinium dorsum and Cryptomonas maculata. Because of their slow growth the last three strains were excluded from further evaluation. Selection criteria were ease of culture, density of cell suspension, stability of motility and gravitactic orientation. The sensitivity toward toxins was tested using copper(II) ions. The instrument allows the user to automatically determine effect-concentration (EC) curves from which the EC(50) values can be calculated. For the interpretation of the EC curves a sigmoid logistic model was proposed which proved to be satisfactory for all tested strains. The inhibition of the motility was considered as the most appropriate movement parameter as an endpoint. The Dunaliella species had the lowest sensitivity to copper with EC(50) values of 220, 198 and 176 mg/L for D. salina, D. bardawil and D. viridis, respectively, followed by T. suecica with an EC(50) value of 40 mg/L. The Prorocentrum species were found to be the most sensitive with an EC(50) value of 13.5 mg/L for P. minimum Lissabon and 7.5 mg/L for P. minimum Kattegat. PMID:16806394

  17. Application of a canine {sup 238}Pu dosimetry model to human bioassay data

    Energy Technology Data Exchange (ETDEWEB)

    Hickman, A.W. Jr. [Florida Univ., Gainesville, FL (United States)

    1991-08-01

    Associated with the use of 2{sup 238}Pu in thermoelectric power sources for space probes and power supplies for cardiac devices is the potential for human exposure to {sup 238}Pu, primarily by inhalation. In the event of human internal exposure, a means is needed for assessing the level of intake and calculating radiation doses. Several bioassay/dosimetry models have been developed for {sup 239}Pu. However, results from studies with laboratory animals have indicated that the biokinetics, and therefore the descriptive models, of {sup 238}Pu are significantly different from those for {sup 239}Pu. A canine model accounting for these differences has been applied in this work to urinary excretion data from seven humans occupationally exposed to low levels of an insoluble {sup 238}Pu compound. The modified model provides a good description of the urinary excretion kinetics observed in the exposed humans. The modified model was also used to provide estimates of the initial intakes of {sup 238}Pu for the seven individuals; these estimates ranged from 4.5 nCi (170 Bq) to 87 nCi (3200 Bq). Autopsy data on the amount and distribution of {sup 238}Pu retained in the organs may be used in the future to validate or refute both these estimates and the assumptions used to formulate the human model. Modification of the human model to simulate an injection exposure to {sup 239}Pu gave patterns of retention in the organs and urinary excretion comparable to those seen previously in humans; further modification of the model using fecal data (unavailable for the subjects of this study) is indicated.

  18. Allelopathy in a leguminous mangrove plant, Derris indica: protoplast co-culture bioassay and rotenone effect.

    Science.gov (United States)

    Inoue, Aya; Mori, Daisuke; Minagawa, Reiko; Fujii, Yoshiharu; Sasamoto, Hamako

    2015-05-01

    To investigate allelopathic activity of a leguminous mangrove plant, Derris indica, the 'Protoplasts Co-culture Method' for bioassay of allelopathy was developed using suspension culture. A suspension culture was induced from immature seed and sub-cultured in Murashige and Skoog's (MS) basal medium containing 10 μM each of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine (BA). The protoplasts were isolated using the separate wells method with 2% each of Cellulase RS, Driselase 20 and Macerozyme R10 in 0.4 M mannitol solution. Protoplast cultures of D. indica revealed that high concentrations of cytokinins, BA and thidiazuron, were effective for cell divisions. The co-cultures of D. indica protoplasts with recipient lettuce protoplasts using 96 multi-well culture plates were performed in MS basal medium containing 0.4 M mannitol solution and 1 μM 2,4-D and 0.1 μM BA. The protoplast density of D. indica used in co-culturing varied from 6 x 10(3) - 10(5) / mL. Very strong inhibitory allelopathic effects of D. indica protoplasts on lettuce protoplast growth were found. A similar strong inhibitory allelopathic activity of dried young leaves on lettuce seedling growth was also observed by using the sandwich method. Rotenone, which is a component of Derris root, dissolved in DMSO, was highly inhibitory on the growth of lettuce protoplasts in culture and this could be one of the causes of the strong allelopathic activity of D. indica. PMID:26058149

  19. The sensitivity of an hydroponic lettuce root elongation bioassay to metals, phenol and wastewaters.

    Science.gov (United States)

    Park, Jihae; Yoon, Jeong-hyun; Depuydt, Stephen; Oh, Jung-Woo; Jo, Youn-min; Kim, Kyungtae; Brown, Murray T; Han, Taejun

    2016-04-01

    The root elongation bioassay is one of the most straightforward test methods used for environmental monitoring in terms of simplicity, rapidity and economy since it merely requires filter paper, distilled water and Petri dishes. However, filter paper as a support material is known to be problematic as it can reduce the sensitivity of the test. The newly developed hydroponic method reported here differs from the conventional root elongation method (US EPA filter paper method) in that no support material is used and the exposure time is shorter (48 h in this test versus 120 h in the US EPA test). For metals, the hydroponic test method was 3.3 (for Hg) to 57 (for Cu) times more sensitive than the US EPA method with the rank orders of sensitivity, estimated from EC50 values, being Cu≥Cd>Ni≥Zn≥Hg for the former and Hg≥Cu≥Ni≥Cd≥Zn for the latter methods. For phenol, the results did not differ significantly; EC50 values were 124 mg L(-1) and 108-180 mg L(-1) for the hydroponic and filter paper methods, respectively. Lettuce was less sensitive than daphnids to wastewaters, but the root elongation response appears to be wastewater-specific and is especially sensitive for detecting the presence of fluorine. The new hydroponic test thus provides many practical advantages, especially in terms of cost and time-effectiveness requiring only a well plate, a small volume of distilled water and short exposure period; furthermore, no specialist expertise is required. The method is simpler than the conventional EPA technique in not using filter paper which can influence the sensitivity of the test. Additionally, plant seeds have a long shelf-life and require little or no maintenance. PMID:26748376

  20. A reliable bioassay procedure to evaluate per os toxicity of Bacillus thuringiensis strains against the rice delphacid, Tagosodes orizicolus (Homoptera: Delphacidae).

    Science.gov (United States)

    Mora, Rebeca; Ibarra, Jorge E; Espinoza, Ana M

    2007-06-01

    A reliable bioassay procedure was developed to test ingested Bacillus thuringiensis (Bt) toxins on the rice delphacid Tagosodes orizicolus. Initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. For the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. Insects were fed through Parafilm membranes on sugar (10 % sucrose) and honey bee (1:48 vol/vol) solutions, observing a natural mortality of 10-15 % and 0-5 %, respectively. Results were reproducible under controlled conditions during the assay (18+/-0.1 degrees C at night and 28+/-0.1 degrees C during the day, 80 % RH and a 12:12 day:light photoperiod). In addition, natural mortality was quantified on insect colonies, collected from three different geographic areas of Costa Rica, with no significant differences between colonies under controlled conditions. Finally, bioassays were performed to evaluate the toxicity of a Bt collection on T. orizicolus. A preliminary sample of twenty-seven Bt strains was evaluated on coarse bioassays using three loops of sporulated colonies in 9 ml of liquid diet, the strains that exhibited higher percentages of T. orizicolus mortality were further analyzed in bioassays using lyophilized spores and crystals (1 mg/ml). As a result, strains 26-O-to, 40-X-m, 43-S-d and 23-O-to isolated from homopteran insects showed mortalities of 74, 96, 44 and 82% respectively while HD-137, HD-1 and Bti showed 19, 83 and 95% mortalities. Controls showed mortalities between 0 and 10% in all bioassays. This is the first report of a reliable bioassay procedure to evaluate per os toxicity for a homopteran species using Bacillus thuringiensis strains. PMID:19069752

  1. Androgenic and estrogenic response of green mussel extracts from Singapore's coastal environment using a human cell-based bioassay.

    Science.gov (United States)

    Bayen, Stéphane; Gong, Yinhan; Chin, Hong Soon; Lee, Hian Kee; Leong, Yong Eu; Obbard, Jeffrey Philip

    2004-11-01

    In the last decade, evidence of endocrine disruption in biota exposed to environmental pollutants has raised serious concern. Human cell-based bioassays have been developed to evaluate induced androgenic and estrogenic activities of chemical compounds. However, bioassays have been sparsely applied to environmental samples. In this study we present data on sex hormone activities in the green mussel, Perna viridis, in Singapore's coastal waters. P.viridis is a common bioindicator of marine contamination, and this study is a follow-up to an earlier investigation that reported the presence of sex hormone activities in seawater samples from Singapore's coastal environment. Specimens were collected from eight locations around the Singapore coastline and analyzed for persistent organic pollutants (POPs) and heavy metals. Tissue extracts were then screened for activities on androgen receptors (ARs) and estrogen receptors (ER-alpha and ER-beta) using a reporter gene bioassay based on a HeLa human cell line. Mussel extracts alone did not exhibit AR activity, but in the presence of the reference androgenic hormone dihydrotestosterone (DHT), activities were up to 340% higher than those observed for DHT alone. Peak activities were observed in locations adjacent to industrial and shipping activities. Estrogenic activities of the mussel extract both alone and in the presence of reference hormone were positive. Correlations were statistically investigated between sex hormone activities, levels of pollutants in the mussel tissues, and various biological parameters (specimen size, sex ratio, lipid and moisture content). Significant correlations exist between AR activities, in the presence of DHT, and total concentration of POPs (r= 0.725, p < 0.05). PMID:15531429

  2. Antihyperglycemic Effect of Orthosiphon Stamineus Benth Leaves Extract and Its Bioassay-Guided Fractions

    Directory of Open Access Journals (Sweden)

    Elsnoussi Ali Hussin Mohamed

    2011-05-01

    Full Text Available Preliminary investigations were carried out to evaluate the antidiabetic effects of the leaves of O. stamineus extracted serially with solvents of increasing polarity (petroleum ether, chloroform, methanol and water; bioassay-guided purification of plant extracts using the subcutaneous glucose tolerance test (SbGTT was also carried out. Only the chloroform extract, given at 1 g/kg body weight (b.w., significantly reduced (P < 0.05 the blood glucose level of rats loaded subcutaneously with 150 mg/kg (b.w. glucose. The active chloroform extract of O. stamineus was separated into five fractions using a dry flash column chromatography method. Out of the five fractions tested, only chloroform fraction 2 (Cƒ2, at the dose of 1 g/kg (b.w. significantly inhibited (P < 0.05 blood glucose levels in SbGTT. Active Cƒ2 was split into two sub-fractions Cƒ2-A and Cƒ2-B, using a dry flash column chromatography method. The activities Cƒ2-A and Cƒ2-B were investigated using SbGTT, and the active sub-fraction was then further studied for anti-diabetic effects in a streptozotocin-induced diabetic rat model. The results clearly indicate that Cƒ2-B fraction exhibited a blood glucose lowering effect in fasted treated normal rats after glucose-loading of 150 mg/kg (b.w.. In the acute streptozotocin-induced diabetic rat model, Cƒ2-B did not exhibit a hypoglycemic effect on blood glucose levels up to 7 hours after treatment. Thus, it appears that Cƒ2-B functions similarly to metformin, which has no hypoglycemic effect but demonstrates an antihyperglycemic effect only in normogycemic models. The effect of Cƒ2-B may have no direct stimulatory effects on insulin secretion or on blood glucose levels in diabetic animal models. Verification of the active compound(s within the active fraction (Cƒ2-B indicated the presence of terpenoids and, flavonoids, including sinensitin.

  3. Efficient screening of dioxins in food and feed using shape-selective pressurized liquid extraction and cell based bioassay analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nording, M. [Swedish Defence Research Agency, Umea (Sweden)]|[Umea Univ. (Sweden). Environmental Chemistry, Dept. of Chemistry; Sporring, S.; Bjoerklund, E. [Lund Univ. (Sweden). Dept. of Analytical Chemistry; Wiberg, K.; Haglund, P. [Umea Univ. (Sweden). Environmental Chemistry, Dept. of Chemistry

    2004-09-15

    Cell based bioassays with enhanced green fluorescent protein (EGFP) detection are potential screening methods for determination of aryl hydrocarbon receptor (AhR) ligands, such as dioxins and similar compounds, in environmental samples. With this technique, it is possible to detect dioxins at levels normally found in food and feed, i.e. pg toxic equivalents (TEQ)/g. Since the signal from the bioassay might be caused by compounds other than dioxins binding to the AhR, determination of the dioxin TEQ generally involve extraction with organic solvents or solvent mixtures, e.g. using a Soxhlet apparatus, followed by clean-up with sulphuric acid or sulphuric acid impregnated silica gel and carbon fractionation in order to exclude possible interferences from the extracts. Until now, sample preparation has been time consuming and labour intensive, but alternatives to traditional methods have recently been developed, with the benefits of shorter analysis times and reduced organic solvent consumption. Pressurized liquid extraction (PLE) may, for instance, be used with a fat retainer in the PLE cell to selectively extract PCBs from food, feed, and biota matrices. In order to further streamline the sample preparation, new assemblies have been developed to fit into a commercially available PLE-equipment. The assemblies are packed with an activated carbon/celite mixture and the sample. In the subsequent extraction, the pollutants are fractionated into three fractions according to their planarity (shape-selective extraction). In the first fraction (I) bulk lipids and PCBs are eluted, in the second fraction (II) the majority of planar (non-ortho) PCBs, and in the third fraction (III), which is back-flushed, the dioxins are recovered. In this way, a pure dioxin fraction may be isolated and analysed separately with the cell based bioassay described above. This study was conducted to meet the imperative demands for dioxin monitoring. The aim was to develop a comprehensive method for

  4. Bioassay case study applying the maximin D-optimal design algorithm to the four-parameter logistic model.

    Science.gov (United States)

    Coffey, Todd

    2015-01-01

    Cell-based potency assays play an important role in the characterization of biopharmaceuticals but they can be challenging to develop in part because of greater inherent variability than other analytical methods. Our objective is to select concentrations on a dose-response curve that will enhance assay robustness. We apply the maximin D-optimal design concept to the four-parameter logistic (4 PL) model and then derive and compute the maximin D-optimal design for a challenging bioassay using curves representative of assay variation. The selected concentration points from this 'best worst case' design adequately fit a variety of 4 PL shapes and demonstrate improved robustness. PMID:26235135

  5. Development and characterization of a green fluorescent protein-based rat cell bioassay system for detection of AH receptor ligands

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Bin; Denison, M. [California Univ., Davis, CA (United States). Dept. of Environmental Toxicology

    2004-09-15

    Proper epidemiological, risk assessment and exposure analysis of TCDD and related HAHs requires accurate measurements of these chemicals both in the species of interest and in various exposure matrices (i.e. biological, environmental, food and feed). While high-resolution instrumental analysis techniques are established for these chemicals, these procedures are very costly, time-consuming and are impractical for large scale sampling studies. Accordingly, numerous bioanalytical methods have been developed for the detection of these chemicals in extracts from a variety of matrices, the majority of which take the advantage of the ability of these chemicals to activate one or more aspects of the AhR-dependent mechanism of action. One of the most sensitive bioassay systems developed to date is the so-called CALUX (Chemically Activated Luciferase Expression) assay, which is based on novel recombinant cell lines that contain a stably transfected dioxin (AhR)-responsive firefly luciferase gene. Treatment of these cells with TCDD and related HAHs and polycyclic aromatic hydrocarbons (PAHs), as well as other AhR ligands, results in induction of reporter gene expression in a time-, dose-, AhR-, and chemical-specific manner. The level of reporter gene expression correlates with the total concentration of the TCDD-like AhR inducers (agonists) present in the sample. Although the firefly luciferase reporter gene contributes to the high degree of sensitivity of the assay, it also has limitations with respect to our need for a rapid and inexpensive bioassay for high-throughput screening analysis. Accordingly, we previously developed a stably transfected murine cell line containing an AhRresponsive enhanced green fluorescent protein (EGFP) reporter gene. This cell line provided us with a high-throughput cell bioassay system for identification and characterization of AhR agonists and antagonists. Here we have extended these studies and describe the development, optimization, and

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

    International Nuclear Information System (INIS)

    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. - In situ bioassays with Chironomus riparius larvae can be a suitable tool to monitor restoration efficiency after a long time of metallic sediment contamination

  7. Characterization of the environmental quality of sediments from two estuarine systems based on different in-vitro bioassays.

    Science.gov (United States)

    Fernandes, Denise; Pujol, Silvia; Pérez-Albaladejo, Elisabet; Tauler, Romà; Bebianno, Maria João; Porte, Cinta

    2014-05-01

    This study characterizes the environmental quality of sediments from the Arade and Guadiana estuaries using different in-vitro bioassays: a) fish hepatoma cell line (PLHC-1) to determine cytotoxicity and presence of CYP1A and oxidative stress inducing agents; b) gonad subcellular fractions from sea bass (Dicentrarchus labrax) to detect compounds that are likely to act as endocrine disrupters by interfering with the synthesis of androgens (CYP17, CYP11β) and estrogens (CYP19). Approximately 60% of extracts from the Arade estuary were cytotoxic when tested at 60 mg eQsed/mL, while only one sample from Guadiana showed cytotoxicity. Sediments from Arade collected close to harbours and waste water effluents were enriched with CYP1A inducing agents, while those from the upper Guadiana induced oxidative stress in PLHC-1 cells. On the other hand, several extracts from both estuaries were able to significantly inhibit CYP17, CYP11β and CYP19 activities in gonad subcellular fractions of sea bass, which indicates the presence of endocrine disrupters, particularly in several sites from the Arade estuary. Overall, the study highlights the usefulness of in-vitro bioassays to identify those sediments that could pose risk to aquatic organisms and that require further action to improve their environmental quality. PMID:24140013

  8. Selection of a bioassay battery to assess toxicity in the affluents and effluents of three water-treatment plants

    Directory of Open Access Journals (Sweden)

    Paola Bohórquez-Echeverry

    2012-08-01

    Full Text Available The assessment of water quality includes the analysis of both physical-chemical and microbiological parameters. However,none of these evaluates the biological effect that can be generated in ecosystems or humans. In order to define the most suitable organismsto evaluate the toxicity in the affluent and effluent of three drinking-water treatment plants, five acute toxicity bioassays were used,incorporating three taxonomic groups of the food chain. Materials and methods. The bioassays used were Daphnia magna and Hydraattenuata as animal models, Lactuca sativa and Pseudokirchneriella subcapitata as plant models, and Photobacterium leioghnathi asbacterial model. To meet this objective, selection criteria of the organisms evaluated and cluster analysis were used to identify the mostsensitive in the affluent and effluent of each plant. Results. All organisms are potentially useful in the assessment of water quality bymeeting four essential requirements and 17 desirable requirements equivalent to 100% acceptability, except P. leioghnathi which doesnot meet two essential requirements that are the IC50 for the toxic reference and the confidence interval. The animal, plant and bacterialmodels showed different levels of sensitivity at the entrance and exit of the water treatment systems. Conclusions. H. attenuata, P.subcapitata and P. leioghnathi were the most effective organisms in detecting toxicity levels in the affluents and D. magna, P. subcapitataand P. leioghnathi in the effluents.

  9. Bioassay-Guided Fractionation of a Leaf Extract from Combretum mucronatum with Anthelmintic Activity: Oligomeric Procyanidins as the Active Principle

    Directory of Open Access Journals (Sweden)

    Verena Spiegler

    2015-08-01

    Full Text Available Combretum mucronatum Schumach. & Thonn. is a medicinal plant widely used in West African traditional medicine for wound healing and the treatment of helminth infections. The present study aimed at a phytochemical characterization of a hydroalcoholic leaf extract of this plant and the identification of the anthelmintic compounds by bioassay-guided fractionation. An EtOH-H2O (1:1 extract from defatted leaves was partitioned between EtOAc and H2O. Further fractionation was performed by fast centrifugal partition chromatography, RP18-MPLC and HPLC. Epicatechin (1, oligomeric proanthocyanidins (OPC 2 to 10 (mainly procyanidins and flavonoids 11 to 13 were identified as main components of the extract. The hydroalcoholic extract, fractions and purified compounds were tested in vitro for their anthelmintic activity using the model nematode Caenorhabditis elegans. The bioassay-guided fractionation led to the identification of OPCs as the active compounds with a dose-dependent anthelmintic activity ranging from 1 to 1000 μM. Using OPC-clusters with a defined degree of polymerization (DP revealed that a DP ≥ 3 is necessary for an anthelmintic activity, whereas a DP > 4 does not lead to a further increased inhibitory effect against the helminths. In summary, the findings rationalize the traditional use of C. mucronatum and provide further insight into the anthelmintic activity of condensed tannins.

  10. Bioassay-guided extraction of crude fucose-containing sulphated polysaccharides from Sargassum fusiforme with response surface methodology

    Science.gov (United States)

    Fu, Zhifei; Li, Haihua; Liu, Hongbing; Hu, Shuman; Li, Yueying; Wang, Mengxue; Guan, Huashi

    2016-06-01

    The response surface methodology (RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides (cFCSP) from Sargassum fusiforme. The central composite design (CCD) was used with four variables, five levels, and four responses. The four variables were pH value of hydrochloric acid solution, extraction temperature (°C), ratio of liquid to raw material (mL g-1), and extraction time (h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of cFCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the pH value of hydrochloric acid solution was 3.50; the extraction temperature was 100°C; the ratio of liquid to raw material was 15.00 mL g-1 and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, cFCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.

  11. Comparative surfactant reactivity of canine and human stratum corneum: a plea for the use of the corneosurfametry bioassay.

    Science.gov (United States)

    Goffin, V; Fontaine, J; Piérard, G E

    1999-01-01

    Comparative dermatology has paid little attention to the physiopathology of the stratum corneum. In this study, we investigated the responses of human and canine horny layers to marketed animal wash products by using the corneosurfametry bioassay. Previous work has shown that, with increasing surfactant aggressiveness to the stratum corneum, the colorimetric index of mildness (CIM) decreases, while both the corneosurfametry index (CSMI) and the overall difference in corneosurfametry (ODC) increase. In the present study, stratum corneum reactivity to wash products and inter-individual variability were significantly higher in humans than in dogs. For the three corneosurfametry variables, linear correlations were found between data gathered in the two panel groups. In conclusion, this pilot study suggests that mean stratum corneum reactivity to surfactants is stronger in humans than in dogs. Inter-individual variation, indicative of sensitive skin, also appears to be broader in humans. As a consequence, data gathered from dogs by using the corneosurfametry bioassay cannot be extrapolated to humans. Such variation between species could be important in the assessment of product safety and in supporting claims for mildness. PMID:25423404

  12. Assessment of the potential toxicity of a linear alkylbenzene sulfonate (LAS) to freshwater animal life by means of cladoceran bioassays.

    Science.gov (United States)

    Coelho, Katiuscia da Silva; Rocha, Odete

    2010-04-01

    The acute and chronic toxic effects of LAS on the cladocerans Daphnia similis, Ceriodaphnia dubia and Ceriodaphnia silvestrii were tested. Both types of toxicity bioassays and the methods of culture and stock maintenance of the test organisms conformed to the recommendations of ABNT (Brazilian Society of Technical Standards), which closely follow the standard methods of USEPA. The results obtained for EC(50) (48 h) were: 14.17 mg L(-1) for D. similis, 11.84 mg L(-1) for C. dubia and 13.52 mg L(-1) for C. silvestrii. In the chronic toxicity tests performed on C. dubia and C. silvestrii, there was a significant decrease in the fecundity of the exposed animals; the value of NOEC for C. dubia and C. silvestrii were 1.00 mg L(-1) and 2.50 mg L(-1), respectively. Cladoceran bioassays provided evidence that LAS concentration as low as 1.00 mg L(-1) can damage invertebrate animal life in freshwaters, concentrations that can be found in many eutrophic rivers and reservoirs. PMID:20091119

  13. Bioassay technique for Plutella xylostella: Leaf-dip method%小菜蛾抗药性监测方法——叶片药膜法

    Institute of Scientific and Technical Information of China (English)

    郭磊; 边全乐; 张宏军; 高希武; 梁沛

    2013-01-01

    The diamondback moth, Plutella xylostella ( L. ) , is a notorious pest insect of cruciferous vegetables. Bioassays are an important technique for insecticide resistance monitoring and for screening the effectiveness of insecticides. This paper describes in detail the extensively used leaf dipping method in the DBM bioassay so as to provide a standard bioassay method for DBM and other lepidopterous pest insects.%小菜蛾Plutella xylostella(L.)是重要的十字花科蔬菜害虫.生物测定是进行害虫抗药性监测及筛选有效防治药剂的重要技术.本文对小菜蛾的生物测定技术进行了详细总结,以期为小菜蛾等鳞翅目害虫幼虫生物测定方法的规范提供依据.

  14. Current and emerging challenges in toxicopathology: Carcinogenic threshold of phenobarbital and proof of arsenic carcinogenicity using rat medium-term bioassays for carcinogens

    International Nuclear Information System (INIS)

    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 the 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

  15. Investigations on sediment toxicity of German rivers applying a standardized bioassay battery.

    Science.gov (United States)

    Hafner, Christoph; Gartiser, Stefan; Garcia-Käufer, Manuel; Schiwy, Sabrina; Hercher, Christoph; Meyer, Wiebke; Achten, Christine; Larsson, Maria; Engwall, Magnus; Keiter, Steffen; Hollert, Henner

    2015-11-01

    River sediments may contain a huge variety of environmental contaminants and play a key role in the ecological status of aquatic ecosystems. Contaminants adsorbed to sediments and suspended solids may contribute directly or after remobilization to an adverse ecological and chemical status of surface water. In this subproject of the joint research project DanTox, acetonic Soxhlet extracts from three German river sediments from the River Rhine (Altrip and Ehrenbreitstein with moderate contamination) and River Elbe (Veringkanal Hamburg heavily contaminated) were prepared and redissolved in dimethyl sulfoxide (DMSO). These extracts were analyzed with a standard bioassay battery with organisms from different trophic levels (bacteria, algae, Daphnia, fish) as well as in the Ames test and the umuC test for bacterial mutagenicity and genotoxicity according to the respective OECD and ISO guidelines. In total, 0.01% (standard) up to 0.25% (only fish embryo test) of the DMSO sediment extract was dosed to the test systems resulting in maximum sediment equivalent concentrations (SEQ) of 2 up to 50 g l(-1). The sediment of Veringkanal near Hamburg harbor was significantly more toxic in most tests compared to the sediment extracts from Altrip and Ehrenbreitstein from the River Rhine. The most toxic effect found for Veringkanal was in the algae test with an ErC50 (72 h) of 0.00226 g l(-1) SEQ. Ehrenbreitstein and Altrip samples were about factor 1,000 less toxic. In the Daphnia, Lemna, and acute fish toxicity tests, no toxicity at all was found at 2 g l(-1) SEQ. corresponding to 0.01% DMSO. Only when increasing the DMSO concentration the fish embryo test showed a 22-fold higher toxicity for Veringkanal than for Ehrenbreitstein and Altrip samples, while the toxicity difference was less evident for the Daphnia test due to the overlaying solvent toxicity above 0.05% dimethyl sulfoxide (DMSO). The higher toxicities observed with the Veringkanal sample are supported by the PAH and PCB

  16. Development of bioassay for pathogenecity testing of Ureaplasma urealyticum as part of host-pathogen communication

    Directory of Open Access Journals (Sweden)

    Purnomo Soeharso

    2005-12-01

    Full Text Available Bioassay of Ureaplasma urealyticum is necessary for detection as well as determination of pathogenic factors in order to understand the pathogenesis of diseases associate with ureaplasma infection. Cultivation and verification of ureaplasma is the first step of this study in the purpose of discovering sensitive method for ureaplasma detection. Cultivation of ureaplasma either in liquid or in solid media are able to detect the existence of ureaplasma in samples analyzed. However, application of PCR using specific primers to be compatible with urease gene (ure would confirm the presence of ureaplasma. The pathogenicity of ureaplasma is potentially monitored using reporter gene as a marker for gene expression. IceC was chosen as reporter gene for ureaplasma pathogenic determination as the gene has great sensitivity, easily detectable and quantitated in simple method of ice nucleation assay. Transposon 916 (Tn916 was selected as a vector for iceC gene to transform ureaplasma. The application of recombinant Tn916-iceC which is considered as pUI, allow detection of ureaplasma activities when transform ureaplasma is tested by ice nucleation assay. It was expected that ureaplasma transformation is the manifestation of mutagenesis which interfere genes responsible for bacterial pathogenicity, in order pathogenesis of bacterial infection to be analyzed accurately. IgA1 protease is considered to be an important factor for ureaplasma pathogenicity as the enzyme is required for successful colonization. Identification of iga gene and  determination of IgA1 protease activity are important for understanding the pathogenesis of ureaplasma infection. Putative iga gene of Mycoplasma genitalium was used as a reference to identify the presence of iga nucleotide sequence in U. urealyticum. Convincing evidence were obtained after PCR amplification of ureaplasma DNA using primers designed to be compatible with putative iga gene of M. genitalium followed by the

  17. Resolutions of ICRP models with BIOKMOD: Application for the bioassays evaluation; Resolucion de los Modelos de la ICRP con BIOKMOD: Aplicacion a la evaluacion de bioensayos

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez, G.

    2005-07-01

    Biokmod is a tool box developed using Mathematic for solving compartmental modes. It gives analytic and numeric solutions. Biokmod solves the current ICRP models including Acute, constant, continuous variable, multi-inputs and random intakes. All parameters (deposition factors, rate transfer coefficients, fractional rate of absorption, etc.) can be modified by users. It can be also applied for evaluating unknown intakes fitting bioassay experimental data and for evacuating uncertainties in the ICRP models. There is a web version (BiokmodWeb) at http://www3.enusa.es//webMathematica/public/biokmode.html. In this article we describe the application of Biokmod for evaluating Bioassays. (Author) 8 refs.

  18. PET/CT Imaging of c-Myc Transgenic Mice Identifies the Genotoxic N-Nitroso-Diethylamine as Carcinogen in a Short-Term Cancer Bioassay

    OpenAIRE

    Katja Hueper; Mahmoud Elalfy; Florian Laenger; Roman Halter; Thomas Rodt; Michael Galanski; Juergen Borlak

    2012-01-01

    BACKGROUND: More than 100,000 chemicals are in use but have not been tested for their safety. To overcome limitations in the cancer bioassay several alternative testing strategies are explored. The inability to monitor non-invasively onset and progression of disease limits, however, the value of current testing strategies. Here, we report the application of in vivo imaging to a c-Myc transgenic mouse model of liver cancer for the development of a short-term cancer bioassay. METHODOLOGY/PRINCI...

  19. Multilaboratory evaluation of 15 bioassays for (eco)toxicity screening and hazard ranking of engineered nanomaterials: FP7 project NANOVALID.

    Science.gov (United States)

    Bondarenko, Olesja M; Heinlaan, Margit; Sihtmäe, Mariliis; Ivask, Angela; Kurvet, Imbi; Joonas, Elise; Jemec, Anita; Mannerström, Marika; Heinonen, Tuula; Rekulapelly, Rohit; Singh, Shashi; Zou, Jing; Pyykkö, Ilmari; Drobne, Damjana; Kahru, Anne

    2016-11-01

    Within EU FP7 project NANOVALID, the (eco)toxicity of 7 well-characterized engineered nanomaterials (NMs) was evaluated by 15 bioassays in 4 laboratories. The highest tested nominal concentration of NMs was 100 mg/l. The panel of the bioassays yielded the following toxicity order: Ag > ZnO > CuO > TiO2 > MWCNTs > SiO2 > Au. Ag, ZnO and CuO proved very toxic in the majority of assays, assumingly due to dissolution. The latter was supported by the parallel analysis of the toxicity of respective soluble metal salts. The most sensitive tests/species were Daphnia magna (towards Ag NMs, 24-h EC50 = 0.003 mg Ag/l), algae Raphidocelis subcapitata (ZnO and CuO, 72-h EC50 = 0.14 mg Zn/l and 0.7 mg Cu/l, respectively) and murine fibroblasts BALB/3T3 (CuO, 48-h EC50 = 0.7 mg Cu/l). MWCNTs showed toxicity only towards rat alveolar macrophages (EC50 = 15.3 mg/l) assumingly due to high aspect ratio and TiO2 towards R. subcapitata (EC50 = 6.8 mg Ti/l) due to agglomeration of TiO2 and entrapment of algal cells. Finally, we constructed a decision tree to select the bioassays for hazard ranking of NMs. For NM testing, we recommend a multitrophic suite of 4 in vitro (eco)toxicity assays: 48-h D. magna immobilization (OECD202), 72-h R. subcapitata growth inhibition (OECD201), 30-min Vibrio fischeri bioluminescence inhibition (ISO2010) and 48-h murine fibroblast BALB/3T3 neutral red uptake in vitro (OECD129) representing crustaceans, algae, bacteria and mammalian cells, respectively. Notably, our results showed that these assays, standardized for toxicity evaluation of "regular" chemicals, proved efficient also for shortlisting of hazardous NMs. Additional assays are recommended for immunotoxicity evaluation of high aspect ratio NMs (such as MWCNTs). PMID:27259032

  20. Assessment of sediment toxicity in the Lagoon of Venice (Italy) using a multi-species set of bioassays.

    Science.gov (United States)

    Picone, Marco; Bergamin, Martina; Losso, Chiara; Delaney, Eugenia; Arizzi Novelli, Alessandra; Ghirardini, Annamaria Volpi

    2016-01-01

    Within the framework of a Weight of Evidence (WoE) approach, a set of four toxicity bioassays involving the amphipod Corophium volutator (10 d lethality test on whole sediment), the sea urchin Paracentrotus lividus (fertilization and embryo toxicity tests on elutriate) and the pacific oyster Crassostrea gigas (embryo toxicity test on elutriate) was applied to sediments from 10 sampling sites of the Venice Lagoon (Italy). Sediments were collected during three campaigns carried out in May 2004 (spring campaign), October 2004 (autumn campaign) and February 2005 (winter campaign). Toxicity tests were performed on all sediment samples. Sediment grain-size and chemistry were measured during spring and autumn campaigns. This research investigated (i) the ability of toxicity tests in discriminating among sites with different contamination level, (ii) the occurrence of a gradient of effect among sampling sites, (iii) the possible correlation among toxicity tests, sediment chemistry, grain size and organic carbon, and (iv) the possible occurrence of toxicity seasonal variability. Sediment contamination levels were from low to moderate. No acute toxicity toward amphipods was observed, while sea urchin fertilization was affected only in few sites in just a single campaign. Short-term effects on larval development of sea urchin and oyster evidenced a clear spatial trend among sites, with increasing effects along the axis connecting the sea-inlets with the industrial area. The set of bioassays allowed the identification of a spatial gradient of effect, with decreasing toxicity from the industrial area toward the sea-inlets. Multivariate data analysis showed that the malformations of oyster embryos were significantly correlated to the industrial contamination (metals, polynuclear aromatic hydrocarbons, hexachlorobenzene and polychlorinated biphenyls), while sea urchin development to sediment concentrations of As, Cr and organic carbon. Both embryo toxicity tests were

  1. Phytotoxicity and Cytotoxicity of Essential Oil from Leaves of Plectranthus amboinicus, Carvacrol, and Thymol in Plant Bioassays.

    Science.gov (United States)

    Pinheiro, Patrícia Fontes; Costa, Adilson Vidal; Alves, Thammyres de Assis; Galter, Iasmini Nicoli; Pinheiro, Carlos Alexandre; Pereira, Alexandre Fontes; Oliveira, Carlos Magno Ramos; Fontes, Milene Miranda Praça

    2015-10-21

    The essential oil of Plectranthus amboinicus and its chemotypes, carvacrol and thymol, were evaluated on the germination and root and aerial growth of Lactuca sativa and Sorghum bicolor and in acting on the cell cycle of meristematic root cells of L. sativa. The main component found in the oil by analysis in gas chromatography-mass spectrometry and gas chromatography flame ionization detection was carvacrol (88.61% in area). At a concentration of 0.120% (w v(-1)), the oil and its chemotypes retarded or inhibited the germination and decreased root and aerial growth in monocot and dicot species used in the bioassays. In addition, all substances caused changes in the cell cycle of the meristematic cells of L. sativa, with chromosomal alterations occurring from the 0.015% (w v(-1)) concentration. The essential oil of P. amboinicus, carvacrol, and thymol have potential for use as bioherbicides. PMID:26416575

  2. Confirmatory sediment analyses and solid and suspended particulate phase bioassays on sediment from Oakland Inner Harbor, San Francisco, California

    Energy Technology Data Exchange (ETDEWEB)

    Word, J.Q.; Ward, J.A.; Apts, C.W.; Woodruff, D.L.; Barrows, M.E.; Cullinan, V.I.; Hyland, J.L.; Campbell, J.F.

    1988-12-01

    The US Army Corps of Engineers (USACE), San Francisco District, was authorized by the US Congress to deepen the navigation channels of Inner and Outer Oakland Harbor, California. During review of the environmental impact statement required for this dredging and disposal project, a panel of national experts approved the open-water disposal of dredged sediment from selected areas within the Inner Harbor, subject to results of confirmatory solid phase bioassays. The San Francisco District of the Corps requested the Battle/Marine Sciences Laboratory (MSL) to conduct these confirmatory studies. The studies provided technical data for an evaluation of the potential environmental impact of this project. Within extremely narrow time constraints, these studies provided chemical and biological information required by ocean dumping regulations to determine suitability of the Oakland Inner Harbor and turning basin sediment for ocean disposal. 23 refs., 18 figs., 45 tabs.

  3. Analysis of carcinogenic activity of some pesticides in a medium-term liver bioassay in the rat.

    Science.gov (United States)

    Hakoi, K; Cabral, R; Hoshiya, T; Hasegawa, R; Shirai, T; Ito, N

    1992-01-01

    Eight pesticides were tested in a medium-term bioassay based upon the induction of preneoplastic lesions in the liver. Rats were initially given diethylnitrosamine intraperitoneally at a dose of 200 mg/kg body weight and 2 weeks later were treated with the pesticides for 6 weeks and then killed; all rats had a partial hepatectomy at week 3. Hepatocarcinogenic potential was assessed by comparing the number and area of glutathione S-transferase placental form positive foci in the liver with those of controls given diethylnitrosamine (DEN) alone. Positive results were seen with p,p-DDT and Triadimefon. Permethrin (mixture of 39% cis form and 61% trans form) showed borderline results. Permethrin (25/75), Deltamethrin, Cypermethrin (52/48), while Trimorphamide and Propineb gave negative results. Our findings provide experimental evidence to indicate that compounds active in this assay have a potential for liver carcinogenicity in rodents. PMID:1363965

  4. Rapid yeast estrogen bioassays stably expressing human estrogen receptors alpha and beta, and green fluorescent protein: a comparison of different compounds on both receptor types

    NARCIS (Netherlands)

    Bovee, T.F.H.; Helsdingen, J.R.; Rietjens, I.M.C.M.; Keijer, J.; Hoogenboom, L.A.P.

    2004-01-01

    Previously, we described the construction of a rapid yeast bioassay stably expressing human estrogen receptor (hER) and yeast enhanced green fluorescent protein (yEGFP) in response to estrogens. In the present study, the properties of this assay were further studied by testing a series of estrogenic

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

    International Nuclear Information System (INIS)

    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

  6. A Choline Oxidase Amperometric Bioassay for the Detection of Mustard Agents Based on Screen-Printed Electrodes Modified with Prussian Blue Nanoparticles

    Directory of Open Access Journals (Sweden)

    Fabiana Arduini

    2015-02-01

    Full Text Available In this work a novel bioassay for mustard agent detection was proposed. The bioassay is based on the capability of these compounds to inhibit the enzyme choline oxidase. The enzymatic activity, which is correlated to the mustard agents, was electrochemically monitored measuring the enzymatic product, hydrogen peroxide, by means of a screen-printed electrode modified with Prussian Blue nanoparticles. Prussian Blue nanoparticles are able to electrocatalyse the hydrogen peroxide concentration reduction at low applied potential (−50 mV vs. Ag/AgCl, thus allowing the detection of the mustard agents with no electrochemical interferences. The suitability of this novel bioassay was tested with the nitrogen mustard simulant bis(2-chloroethylamine and the sulfur mustard simulants 2-chloroethyl ethyl sulfide and 2-chloroethyl phenyl sulfide. The bioassay proposed in this work allowed the detection of mustard agent simulants with good sensitivity and fast response, which are excellent premises for the development of a miniaturised sensor well suited for an alarm system in case of terrorist attacks.

  7. Predicting Field Control of Tarnished Plant Bug (Heteroptera: Miridae) Populations with Pyrethroid Insecticides by Use of Two Glass-Vial Bioassays

    Science.gov (United States)

    Tarnished plant bug, Lygus lineolaris (Palisot de beauvois), populations from 21 locations in the Mississippi River Delta of Arkansas and Mississippi were tested for resistance to permethrin in 2004 and 2005. Each population was tested using permethrin in a discriminating-dose bioassay to determine...

  8. The Vibrio harveyi bioassay used routinely to detect AI-2 quorum sensing inhibition is confounded by inconsistent normalization across marine matrices.

    Science.gov (United States)

    Blair, Walter M; Doucette, Gregory J

    2013-03-01

    The Vibrio harveyi autoinducer-2 (AI-2) bioassay is used routinely to screen for inhibition of the AI-2 quorum sensing system. The present study utilizes three well-described bacterial strains to demonstrate that inconsistent normalization across matrices undermines the assay's use in screening marine samples for AI-2 inhibition. PMID:23305926

  9. TOXICITY BIOASSAY AND ELUATE HEAVY METALS ANALYSIS RESULTS OF THE BENCH SCALE STABILIZATION STUDY OF SOILS FROM THE UNITED CHROME SUPERFUND NFL SITE CORVALLIS, OREGON

    Science.gov (United States)

    In support of Environmental Protection Agency Region 10 and their United Chrome studies the staff at Environmental Research Laboratory-Corvallis performed toxicity bioassays and selected chemical analyses. Direct toxicity tests (i.e. using soil as the medium) and indirect toxicit...

  10. WILL THE MOUSE BIOASSAY FOR ESTIMATING SENSORY IRRITANCY OF AIRBORNE CHEMICALS (ASTM E 981-84) BE USEFUL FOR EVALUATION OF INDOOR AIR CONTAMINANTS

    Science.gov (United States)

    For many toxic inhalants, sensory irritation is the first detectable response. tandardized bioassay, ASTM E 981-84, that quantitates irritancy as a reduction in breathing rate of the mouse during inhalation exposure, has been developed. he validation of this screen for detecting ...

  11. Screening for estrogen residues in calf urine: Comparison of a validated yeast estrogen bioassay and gas chromatography-tandem mass spectrometry

    NARCIS (Netherlands)

    Nielen, M.W.F.; Bovee, T.F.H.; Heskamp, H.H.; Lasaroms, J.J.P.; Sanders, M.B.; Rhijn, van J.A.; Groot, M.J.; Hoogenboom, L.A.P.

    2006-01-01

    Within the European Union, the control for residues of illegal hormones in food-producing animals is based on urine analysis for a few target analytes using gas chromatography/mass spectrometry and/or liquid chromatography¿tandem mass spectrometry. Recently, we developed a robust yeast bioassay scre

  12. Investigating the significance of dissolved organic contaminants in aquatic environments: coupling passive sampling with in vitro bioassays.

    Science.gov (United States)

    Emelogu, Emmanuel S; Pollard, Pat; Robinson, Craig D; Smedes, Foppe; Webster, Lynda; Oliver, Ian W; McKenzie, Craig; Seiler, T B; Hollert, Henner; Moffat, Colin F

    2013-01-01

    We investigated the feasibility of coupling passive sampling and in vitro bioassay techniques for both chemical and ecotoxicological assessment of complex mixtures of organic contaminants in water. Silicone rubber passive sampling devices (SR-PSDs) were deployed for 8-9 weeks in four streams and an estuary of an agricultural catchment in North East (NE) Scotland. Extracts from the SR-PSDs were analysed for freely dissolved hydrophobic organic contaminants (HOCs) and screened for wide range of pesticides. The total concentrations of dissolved PAHs (∑PAH(40), parent and branched) in the water column of the catchment varied from 38 to 69 ng L(-1), whilst PCBs (∑PCB(32)) ranged 0.02-0.06 ng L(-1). A number and level of pesticides and acid/urea herbicides of varying hydrophobicity (logK(OW)s ~2.25 to ~5.31) were also detected in the SR extracts, indicating their occurrence in the catchment. The acute toxicity and EROD induction potentials of SR extracts from the study sites were evaluated with rainbow trout liver (Oncorhynchus mykiss; RTL-W1) cell line. Acute cytotoxicity was not observed in cells following 48 h exposure to the SR extracts using neutral red uptake assay as endpoint. But, on a sublethal level, for every site, statistically significant EROD activity was observed to some degree following 72 h exposure to extracts, indicating the presence of compounds with dioxin-like effect that are bioavailable to aquatic organisms in the water bodies of the catchment. Importantly, only a small fraction of the EROD induction could be attributed to the PAHs and PCBs that were determined. This preliminary study demonstrates that the coupling of silicone rubber passive sampling techniques with in vitro bioassays is feasible and offers a cost effective early warning signal on water quality deterioration. PMID:22850278

  13. WE-E-BRE-03: Biological Validation of a Novel High-Throughput Irradiator for Predictive Radiation Sensitivity Bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, TL; Martin, JA; Shepard, AJ; Bailey, AM; Nickel, KP; Kimple, RJ; Bednarz, BP [University of Wisconsin, Madison, WI (United States)

    2014-06-15

    Purpose: The large dose-response variation in both tumor and normal cells between individual patients has led to the recent implementation of predictive bioassays of patient-specific radiation sensitivity in order to personalize radiation therapy. This exciting new clinical paradigm has led us to develop a novel high-throughput, variable dose-rate irradiator to accompany these efforts. Here we present the biological validation of this irradiator through the use of human cells as a relative dosimeter assessed by two metrics, DNA double-strand break repair pathway modulation and intercellular reactive oxygen species production. Methods: Immortalized human tonsilar epithelial cells were cultured in 96-well micro titer plates and irradiated in groups of eight wells to absorbed doses of 0, 0.5, 1, 2, 4, and 8 Gy. High-throughput immunofluorescent microscopy was used to detect γH2AX, a DNA double-strand break repair mechanism recruiter. The same analysis was performed with the cells stained with CM-H2DCFDA that produces a fluorescent adduct when exposed to reactive oxygen species during the irradiation cycle. Results: Irradiations of the immortalized human tonsilar epithelial cells at absorbed doses of 0, 0.5, 1, 2, 4, and 8 Gy produced excellent linearity in γH2AX and CM-H2DCFDA with R2 values of 0.9939 and 0.9595 respectively. Single cell gel electrophoresis experimentation for the detection of physical DNA double-strand breaks in ongoing. Conclusions: This work indicates significant potential for our high-throughput variable dose rate irradiator for patient-specific predictive radiation sensitivity bioassays. This irradiator provides a powerful tool by increasing the efficiency and number of assay techniques available to help personalize radiation therapy.

  14. Toxicity of sediment-bound pollutants in the Seine estuary, France, using a Eurytemora affinis larval bioassay.

    Science.gov (United States)

    Lesueur, Teddy; Boulangé-Lecomte, Céline; Restoux, Gwendal; Deloffre, Julien; Xuereb, Benoît; Le Menach, Karyn; Budzinski, Hélène; Petrucciani, Nathalie; Marie, Sabine; Petit, Fabienne; Forget-Leray, Joëlle

    2015-03-01

    Coastal urbanisation exposes surrounding estuarine environments to urban-related contaminants such as polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs) and pesticide mixtures. Hydrophobic contaminants can adsorb on estuarine sediments. They can subsequently be released on a massive scale in the aquatic environment due to artificial or natural phenomena (e.g. dredging, tides), thereby threatening living organisms. The contamination of sediment is a significant ecological issue in the Seine estuary, France. However, few relevant methods have been developed to assess sediment toxicity and its ecological impacts in a cost-effective way. In this context, we aimed to assess the toxicity of natural sediments from the Seine estuary on the development of the calanoid copepod Eurytemora affinis using a previously developed larval bioassay. This assay involves direct exposure of nauplii to elutriates of sediments for six days. Sediments were collected along the Seine estuary from six polluted sites and one reference site. Pollutants in this estuary included PAHs, PCBs and OCPs (organochlorine pesticides). Nauplius survival was significantly more affected by exposure to all contaminated sediment elutriates, than by exposure to sediment from Yville-sur-Seine (the reference site), whereas nauplius growth was significantly reduced after exposure to contaminated sediment elutriates from four of the six contaminated sites. We identified two distinct site clusters, one including both the sand-rich and the least polluted sediments (Oissel, Quillebeuf-sur-Seine, Caudebec-en-Caux) and the other including both the clay- and silt-rich, and the most polluted sediments (La Bouille, Poses, Pont de Normandie). As expected, survival was significantly more impacted after exposure to elutriates from the second cluster than from the first. This work enables (i) assessment of the toxicity of natural sediments in the Seine estuary and (ii) validation of the larval bioassay

  15. Genotoxicity of industrial wastewaters obtained from two different pollution sources in northern India: a comparison of three bioassays.

    Science.gov (United States)

    Fatima, Riffat A; Ahmad, Masood

    2006-10-10

    The genotoxicity of industrial wastewater samples from Aligarh and Ghaziabad cities was compared using the Ames plate incorporation test, the Ames fluctuation test and the Allium cepa test. While TA102 and TA104 strains exhibited the highest sensitivity against the Aligarh sample (AWW) in terms of the slope (m) of the dose-response curve in the plate incorporation assay, TA98 and TA97a were the most sensitive strains based on the induction factor, Mi(p). TA98 once again, was the most sensitive strain against the test sample from Ghaziabad (GWW) in terms of 'Mi(p)' while TA102 was the most sensitive strain on the basis of the slope (m). TA100 displayed the highest susceptibility towards the samples from Aligarh in the fluctuation test. However, TA102 and TA98 responded maximally to GWW in this bioassay. The mutagenicity of the test samples seemed to be partly mediated by reactive oxygen species (ROS) as evidenced by the use of free radical scavengers. Mannitol brought about the maximum decline in the number of revertants of TA102 by the Aligarh sample, whereas such a reduction in case of Ghaziabad sample was exhibited with superoxide dismutase. Both the test water samples induced various anaphase aberrations in the root cells of Allium cepa. Fragmentation of the chromosome was the predominant effect of the Aligarh water sample while the Ghaziabad sample induced chromosome stickiness. The crucial roles of heavy metals and pesticides in the genotoxicity of AWW and GWW, respectively, have been suggested. In view of the problem associated with the interpretations of data, we recommend that all the test bioassays should be carried out in the presence of ROS scavengers for the fool proof evaluation of the genotoxicity of water samples. PMID:16887378

  16. Enhancement of preneoplastic lesion yield by Chios Mastic Gum in a rat liver medium-term carcinogenesis bioassay

    International Nuclear Information System (INIS)

    The mastic (Pistacia lentiscus var. chia) tree is native throughout the Mediterranean region and has long proved a source of food additives and medical treatments. To investigate the modifying effects of Chios Mastic Gum on rat liver carcinogenesis, 6-week-old male F344 rats were subjected to the established rat liver medium-term carcinogenesis bioassay (Ito-test). At the commencement, rats (groups 1-4) were intraperitoneally injected with 200 mg/kg body weight of diethylnitrosamine (DEN). After two weeks, mastic was added to CRF (Charles River Formula)-1 powdered basal diet at doses of 0, 0.01, 0.1 and 1% in groups 1-4, respectively. At week 3, all rats were underwent two-thirds partial hepatectomy. The experiment was terminated at week 8. As results show, liver weights were significantly increased in a mastic dose-dependent manner among groups 1-4. The numbers (/cm2) and the areas (mm2/cm2) of glutathione S-transferase placental form (GST-P)-positive cell foci (≥ 0.2 mm in diameter) were significantly increased in the DEN-1% group compared to the DEN-alone group, along with the average areas per foci and larger-sized foci (≥ 0.4 mm). 5-Bromo-2'-deoxyuridine (BrdU) + GST-P double-immunohistochemistry showed the highest BrdU-labeling indices within GST-P foci in the DEN-1% group. 8-hydroxydeoxyguanosine (8-OHdG) levels in liver DNA did not vary, while real-time quantitative polymerase chain reaction (PCR) analysis of livers revealed many up- or down-regulated genes in the DEN-1% group. In conclusion, this is the first report to display a promotion potential of Chios Mastic Gum on the formation of preneoplastic lesions in the established rat liver medium-term carcinogenesis bioassay

  17. Optimization of an in vitro bioassay to monitor growth and formation of myotubes in real time.

    Science.gov (United States)

    Murphy, Sylvia M; Kiely, Maeve; Jakeman, Philip M; Kiely, Patrick A; Carson, Brian P

    2016-06-01

    The importance of growth and maintenance of skeletal muscle is vital for long term health and quality of life. Appropriate nutrition with specific bioactivities relevant to the functionalities of tissues such as skeletal muscle, can assist in maintaining and promoting adaptive responses to biological and environmental stresses which prevent muscle atrophy and promote hypertrophy. The aim of this investigation was to develop a novel in vitro cell-based electric impedance assay to study myoblast to myotube formation on the real time cell analysis (RTCA) platform (xCELLigence™, ACEA) and to validate the system by testing myotube responses to hypertrophic stimuli. C2C12 myoblasts were proliferated until 70% confluent in Dulbecco's Modified Eagles Medium (DMEM) (10% FBS) and subsequently differentiated to myotubes over 8 days in DMEM [2% horse serum (HS)]. Changes in cell behaviour and adhesion properties were monitored by measuring impedance via interdigitated microelectrodes in the base of E-16 cell culture dishes. To establish the suitability of this assay to monitor nutrient regulation of muscle hypertrophy, leucine, a known potent regulator of MPS was then supplemented to the fully formed myotubes in physiologically relevant conditions-0.20 mM, 0.40 mM, 0.6 mM, 0.8 mM and above 1.0 mM, 1.5 mM, 2.0 mM and impedance subsequently monitored. Parallel experiments highlighting alterations in myotube thickness, muscle protein synthesis (MPS) (mammalian target of rapamycin; mTOR) and differentiation (myogenin) were conducted to support RTCA bioassay findings. This in vitro bioassay can be used to monitor skeletal muscle behaviour and identify nutrient compounds with bioactivities promoting skeletal muscle hypertrophy, reducing muscle atrophy and thus inform the development of novel nutrient formulations for the maintenance of skeletal muscle. PMID:27009307

  18. Label-Free and Separation-Free Atomic Fluorescence Spectrometry-Based Bioassay: Sensitive Determination of Single-Strand DNA, Protein, and Double-Strand DNA.

    Science.gov (United States)

    Chen, Piaopiao; Wu, Peng; Chen, Junbo; Yang, Peng; Zhang, Xinfeng; Zheng, Chengbin; Hou, Xiandeng

    2016-02-16

    Based on selective and sensitive determination of Hg(2+) released from mercury complex by cold vapor generation (CVG) atomic fluorescence spectrometry (AFS) using SnCl2 as a reductant, a novel label-free and separation-free strategy was proposed for DNA and protein bioassay. To construct the DNA bioassay platform, an Hg(2+)-mediated molecular beacon (hairpin) without labeling but possessing several thymine (T) bases at both ends was employed as the probe. It is well-known that Hg(2+) could trigger the formation of the hairpin structure through T-Hg(2+)-T connection. In the presence of a specific target, the hairpin structure could be broken and the captured Hg(2+) was released. Interestingly, it was found that SnCl2 could selectively reduce only free Hg(2+) to Hg(0) vapor in the presence of T-Hg(2+)-T complex, which could be separated from sample matrices for sensitive AFS detection. Three different types of analyte, namely, single-strand DNA (ssDNA), protein, and double-strand DNA (dsDNA), were investigated as the target analytes. Under the optimized conditions, this bioassay provided high sensitivity for ssDNA, protein, and dsDNA determination with the limits of detection as low as 0.2, 0.08, and 0.3 nM and the linear dynamic ranges of 10-150, 5-175, and 1-250 nM, respectively. The analytical performance for these analytes compares favorably with those by previously reported methods, demonstrating the potential usefulness and versatility of this new AFS-based bioassay. Moreover, the bioassay retains advantages of simplicity, cost-effectiveness, and sensitivity compared to most of the conventional methods. PMID:26781421

  19. 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

    Energy Technology Data Exchange (ETDEWEB)

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

    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 particular bioassay system.

  20. Development of a bioassay to screen for chemicals mimicking the anti-aging effects of calorie restriction

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Takuya, E-mail: takuya@nagasaki-u.ac.jp [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Tsuchiya, Tomoshi [Division of Surgical Oncology, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501 (Japan); Komatsu, Toshimitsu; Mori, Ryoichi; Hayashi, Hiroko [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Shimano, Hitoshi [Department of Internal Medicine (Endocrinology and Metabolism), Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba Ibaraki 305-8575 (Japan); Spindler, Stephen R. [Department of Biochemistry, Room 5478, Boyce Hall, University of California - Riverside, Riverside, CA 92521 (United States); Shimokawa, Isao [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2010-10-15

    Research highlights: {yields} We identified four sequence motifs lying upstream of putative pro-longevity genes. {yields} One of these motifs binds to HNF-4{alpha}. {yields} HNF-4{alpha}/PGC-1{alpha} could up-regulate the transcription of a reporter gene linked to this motif. {yields} The reporter system described here could be used to screen candidate anti-aging molecules. -- Abstract: Suppression of the growth hormone/insulin-like growth factor-I pathway in Ames dwarf (DF) mice, and caloric restriction (CR) in normal mice extends lifespan and delays the onset of age-related disorders. In combination, these interventions have an additive effect on lifespan in Ames DF mice. Therefore, common signaling pathways regulated by DF and CR could have additive effects on longevity. In this study, we tried to identity the signaling mechanism and develop a system to assess pro-longevity status in cells and mice. We previously identified genes up-regulated in the liver of DF and CR mice by DNA microarray analysis. Motif analysis of the upstream sequences of those genes revealed four major consensus sequence motifs, which have been named dwarfism and calorie restriction-responsive elements (DFCR-REs). One of the synthesized sequences bound to hepatocyte nuclear factor-4{alpha} (HNF-4{alpha}), an important transcription factor involved in liver metabolism. Furthermore, using this sequence information, we developed a highly sensitive bioassay to identify chemicals mimicking the anti-aging effects of CR. When the reporter construct, containing an element upstream of a secreted alkaline phosphatase (SEAP) gene, was co-transfected with HNF-4{alpha} and its regulator peroxisome proliferator-activated receptor (PPAR) {gamma} coactivator-1{alpha} (PGC-1{alpha}), SEAP activity was increased compared with untransfected controls. Moreover, transient transgenic mice established using this construct showed increased SEAP activity in CR mice compared with ad libitum-fed mice. These data

  1. Polyvinyl polypyrrolidone attenuates genotoxicity of silver nanoparticles synthesized via green route, tested in Lathyrus sativus L. root bioassay.

    Science.gov (United States)

    Panda, Kamal K; Achary, V Mohan M; Phaomie, Ganngam; Sahu, Hrushi K; Parinandi, Narasimham L; Panda, Brahma B

    2016-08-01

    The silver nanoparticles (AgNPs) were synthesized extracellularly from silver nitrate (AgNO3) using kernel extract from ripe mango Mengifera indica L. under four different reaction conditions of the synthesis media such as the (i) absence of the reducing agent, trisodium citrate (AgNPI), (ii) presence of the reducing agent (AgNPII), (iii) presence of the cleansing agent, polyvinyl polypyrrolidone, PVPP (AgNPIII), and (iv) presence of the capping agent, polyvinyl pyrrolidone, PVP (AgNPIV). The synthesis of the AgNPs was monitored by UV-vis spectrophotometry. The AgNPs were characterised by the energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and small-angle X-ray scattering. Functional groups on the AgNPs were established by the Fourier transform infrared spectroscopy. The AgNPs (AgNPI, AgNPII, AgNPIII and AgNPIV) were spherical in shape with the diameters and size distribution-widths of 14.0±5.4, 19.2±6.6, 18.8±6.6 and 44.6±13.2nm, respectively. Genotoxicity of the AgNPs at concentrations ranging from 1 to 100mgL(-1) was determined by the Lathyrus sativus L. root bioassay and several endpoint assays including the generation of reactive oxygen species and cell death, lipid peroxidation, mitotic index, chromosome aberrations (CA), micronucleus formation (MN), and DNA damage as determined by the Comet assay. The dose-dependent induction of genotoxicity of the silver ion (Ag(+)) and AgNPs was in the order Ag(+)>AgNPII>AgNPI>AgNPIV>AgNPIII that corresponded with their relative potencies of induction of DNA damage and oxidative stress. Furthermore, the findings underscored the CA and MN endpoint-based genotoxicity assay which demonstrated the genotoxicity of AgNPs at concentrations (≤10mgL(-1)) lower than that (≥10mgL(-1)) tested in the Comet assay. This study demonstrated the protective action of PVPP against the genotoxicity of AgNPIII which was independent of the size of the AgNPs in the L. sativus L. root bioassay

  2. Single-step bioassays in serum and whole blood with a smartphone, quantum dots and paper-in-PDMS chips.

    Science.gov (United States)

    Petryayeva, Eleonora; Algar, W Russ

    2015-06-21

    The development of nanoparticle-based bioassays is an active and promising area of research, where point-of-care (POC) diagnostics are one of many prospective applications. Unfortunately, the majority of nanoparticle-based assays that have been developed to date have failed to address two important considerations for POC applications: use of instrumentation amenable to POC settings, and measurement of analytes in biological sample matrices such as serum and whole blood. To address these considerations, we present design criteria and demonstrate proof-of-concept for a semiconductor quantum dot (QD)-based assay format that utilizes smartphone readout for the single-step, Förster resonance energy transfer (FRET)-based detection of hydrolase activity in serum and whole blood, using thrombin as a model analyte. Important design criteria for assay development included (i) the size and emission wavelength of the QDs, which had to balance brightness for smartphone imaging, optical transmission through blood samples, and FRET efficiency for signaling; (ii) the wavelength of a light-emitting diode (LED) excitation source, which had to balance transmission through blood and the efficiency of excitation of QDs; and (iii) the use of an array of paper-in-polydimethylsiloxane (PDMS)-on-glass sample chips to reproducibly limit the optical path length through blood to ca. 250 μm and permit multiplexing. Ultimately, CdSe/CdS/ZnS QDs with peak emission at 630 nm were conjugated with Alexa Fluor 647-labeled peptide substrates for thrombin and immobilized on paper test strips inside the sample cells. This FRET system was sensitive to thrombin activity, where the recovery of QD emission with hydrolytic loss of FRET permitted kinetic assays in buffer, serum and whole blood. Quantitative results were obtained in less than 30 min with a limit of detection 18 NIH units mL(-1) of activity in 12 μL of whole blood. Proof-of-concept for a competitive binding assay was also demonstrated with

  3. Development of a bioassay to screen for chemicals mimicking the anti-aging effects of calorie restriction

    International Nuclear Information System (INIS)

    Research highlights: → We identified four sequence motifs lying upstream of putative pro-longevity genes. → One of these motifs binds to HNF-4α. → HNF-4α/PGC-1α could up-regulate the transcription of a reporter gene linked to this motif. → The reporter system described here could be used to screen candidate anti-aging molecules. -- Abstract: Suppression of the growth hormone/insulin-like growth factor-I pathway in Ames dwarf (DF) mice, and caloric restriction (CR) in normal mice extends lifespan and delays the onset of age-related disorders. In combination, these interventions have an additive effect on lifespan in Ames DF mice. Therefore, common signaling pathways regulated by DF and CR could have additive effects on longevity. In this study, we tried to identity the signaling mechanism and develop a system to assess pro-longevity status in cells and mice. We previously identified genes up-regulated in the liver of DF and CR mice by DNA microarray analysis. Motif analysis of the upstream sequences of those genes revealed four major consensus sequence motifs, which have been named dwarfism and calorie restriction-responsive elements (DFCR-REs). One of the synthesized sequences bound to hepatocyte nuclear factor-4α (HNF-4α), an important transcription factor involved in liver metabolism. Furthermore, using this sequence information, we developed a highly sensitive bioassay to identify chemicals mimicking the anti-aging effects of CR. When the reporter construct, containing an element upstream of a secreted alkaline phosphatase (SEAP) gene, was co-transfected with HNF-4α and its regulator peroxisome proliferator-activated receptor (PPAR) γ coactivator-1α (PGC-1α), SEAP activity was increased compared with untransfected controls. Moreover, transient transgenic mice established using this construct showed increased SEAP activity in CR mice compared with ad libitum-fed mice. These data suggest that because of its rapidity, ease of use, and specificity

  4. Are combined AOPs effective for toxicity reduction in receiving marine environment? Suitability of battery of bioassays for wastewater treatment plant (WWTP) effluent as an ecotoxicological assessment.

    Science.gov (United States)

    Díaz-Garduño, B; Rueda-Márquez, J J; Manzano, M A; Garrido-Pérez, C; Martín-Díaz, M L

    2016-03-01

    Ecotoxicological assessment of three different wastewater treatment plant (WWTP) effluents D1, D2 and D3 was performed before and after tertiary treatment using combination of advanced oxidation processes (AOPs). A multibarrier treatment (MBT) consisting of microfiltration (MF), hydrogen peroxide photolysis (H2O2/UVC) and catalytic wet peroxide oxidation (CWPO) was applied for all effluents. Sparus aurata, Paracentrotus lividus, Isochrysis galbana and Vibrio fischeri, representing different trophic levels, constituted the battery of bioassays. Different acute toxicity effects were observed in each WWTP effluents tested. The percentage of sea urchin larval development and mortality fish larvae were the most sensitive endpoints. Significant reduction (p effluent's toxicity was observed using a classification pT-method after MBT process. Base on obtained results, tested battery of bioassays in pT-method framework can be recommended for acute toxicity preliminary evaluation of WWTP effluents for the marine environment. PMID:26741736

  5. Anti-adipogenic activities of Alnus incana and Populus balsamifera bark extracts, part II: bioassay-guided identification of actives salicortin and oregonin.

    Science.gov (United States)

    Martineau, Louis C; Muhammad, Asim; Saleem, Ammar; Hervé, Jessica; Harris, Cory S; Arnason, John T; Haddad, Pierre S

    2010-10-01

    Among modern day metabolic diseases, obesity has reached epidemic proportions worldwide and novel therapeutic support strategies are urgently needed. Adipocytes are interesting targets in this context. Using ethnobotanical and bioassay screening techniques, we have identified two Boreal Forest plants used by the James Bay Cree that potently inhibit adipogenesis, namely ALNUS INCANA ssp. RUGOSA (Speckled Alder) and POPULUS BALSAMIFERA (Balsam Poplar). The mode of action of this inhibitory activity was reported in a companion paper. The current study report the results of a classical bioassay-guided fractionation approach aimed at identifying the active principles responsible for the inhibition of adipogenesis, as measured using triglyceride accumulation in the 3T3-L1 adipocyte model cell line. The glycosides oregonin and salicortin were isolated and identified as the respective active principles for ALNUS INCANA and POPULUS BALSAMIFERA. These compounds thus offer promise as novel agents to mitigate the incidence or the progression of obesity. PMID:20301058

  6. Utilizing an earthworm bioassay (Eisenia andrei) to assess a South African soil screening value with regards to effects from a copper manufacturing industry.

    Science.gov (United States)

    Maboeta, Mark; Fouché, Tanya

    2014-09-01

    Metal contamination of soil due to industrialization has become an increasingly important problem in South Africa. This study aimed to investigate the potential impact of a copper (CuSO4·5H2O) production company on the soil environment. Bioassays using Eisenia andrei were performed to assess changes in biomass, reproduction and a biomarker, neutral red retention time, over a 28 day period. Earthworms exposed to soils from the Cu production site differed significantly (p < 0.05) from those exposed to soils 500 m and 5 km away in terms of the measured endpoints. These findings are consistent with the results from the chemical analysis which showed an elevated soil Cu content for both sites closest to the chemical production company compared to the reference site. The results confirm the importance and predictive value of using bioassays in conjunction with chemical analysis during soil quality assessments. PMID:24875827

  7. Detection of endocrine active substances in the aquatic environment in southern Taiwan using bioassays and LC-MS/MS.

    Science.gov (United States)

    Chen, Kuang-Yu; Chou, Pei-Hsin

    2016-06-01

    Endocrine active substances, including naturally occurring hormones and various synthetic chemicals have received much concern owing to their endocrine disrupting potencies. It is essential to monitor their environmental occurrence since these compounds may pose potential threats to biota and human health. In this study, yeast-based reporter assays were carried out to investigate the presence of (anti-)androgenic, (anti-)estrogenic, and (anti-)thyroid compounds in the aquatic environment in southern Taiwan. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was also used to measure the environmental concentrations of selected endocrine active substances for assessing potential ecological risks and characterizing contributions to the endocrine disrupting activities. Bioassay results showed that anti-androgenic (ND-7489 μg L(-1) flutamide equivalent), estrogenic (ND-347 ng L(-1) 17β-estradiol equivalent), and anti-thyroid activities were detected in the dissolved and particulate phases of river water samples, while anti-estrogenic activities (ND-10 μg L(-1) 4-hydroxytamoxifen equivalent) were less often found. LC-MS/MS analysis revealed that anti-androgenic and estrogenic contaminants, such as bisphenol A, triclosan, and estrone were frequently detected in Taiwanese rivers. In addition, their risk quotient values were often higher than 1, suggesting that they may pose an ecological risk to the aquatic biota. Further identification of unknown anti-androgenic and estrogenic contaminants in Taiwanese rivers may be necessary to protect Taiwan's aquatic environment. PMID:26971174

  8. Evaluation of mixture effects in a crude extract of compost using the CALUX bioassay and HPLC fractionation

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, G.; Takigami, H.; Sakai, S.I. [National Inst. for Environmental Studies, Yatabe, Ibaraki (Japan). Research Center for Material Cycles and Waste Management; Kushi, Y. [Obihiro Univ. of Agriculture and Veternary Medicine (Japan). Dept. of Bioresource Science

    2004-09-15

    In general, crude extracts and polyaromatic hydrocarbon (PAC)-containing fractions of environmental samples show high activities in the AHR-based bioassay. Although many studies have tried to determine which compounds contribute to this activity based on additivity theory, these values are higher than the corresponding chemically calculated IEQs or TEQ values. These compounds in environmental samples exist as mixtures, and interactions between compounds must be considered in chemical risk assessments. In particular, if synergistic interactions occur in environmental samples, application of the additivity assessment would underestimate real chemical risk. In this study, we investigated mixture effects in an extract of an environmental sample. First we established a simple fractionation procedure for the sample, and then we examined the retention characteristics of PACs using RP-HPLC on an octadecylsilica (ODS) column. Then we applied HPLC fractionation and combined CALUX (DR-CALUX {sup registered}: Dioxin-Responsive Chemical- Activated Luciferase gene expression)/chemical analysis to a night soil sludge (NSS) compost extract to determine which compounds contributed to the CALUX-TEQ (2,3,7,8-TCDD equivalent) of the crude extract. Finally, to assess the mixture effects, we exposed the HPLC fractions to CALUX cells in the presence of 2,3,7,8-TCDD at concentration levels similar to those in the original compost sample and determined whether there was a synergistic interaction between the sample fraction and 2,3,7,8-TCDD in terms of CALUX activity.

  9. Re-evaluation of the kidney tumors and renal histopathology occurring in a 2-year rat carcinogenicity bioassay of quercetin.

    Science.gov (United States)

    Hard, Gordon C; Seely, John Curtis; Betz, Laura J; Hayashi, Shim-Mo

    2007-04-01

    Renal histopathology in the most recent 2-year carcinogenicity bioassay of quercetin, in Fischer 344 rats, was re-evaluated in an attempt to determine a mode of action underlying a small increase in renal tubule tumors reported in the males (). The re-evaluation confirmed the reported increase in renal tumors in mid- and high-dose males, including a single carcinoma in a high-dose male, as well as an exacerbation of spontaneous, chronic progressive nephropathy (CPN) in male rats only. The re-evaluation also showed that there were no cellular alterations in the kidney indicative of chemical toxicity at 6 months, 15 months, or 2 years. The evidence linked the occurrence of the predominant basophilic adenomas and foci of atypical tubule hyperplasia (ATH) with the exacerbation of CPN to advanced grades of severity, supporting a mode of action involving quercetin interaction with CPN. This mode of action represents a secondary mechanism for renal tumor development, with no relevance for extrapolation to humans. In addition, the single carcinoma present in the high-dose males, along with 4 other lesions ranging from ATH to adenoma in male and female groups, were considered to have a unique phenotype associated previously with neoplasms of spontaneous and familial origin. PMID:17156907

  10. Ovarian 32P uptake in the homoplastic hypophysectomized catfish, Heteropneustes fossilis as an end point for gonadotropin bioassay

    International Nuclear Information System (INIS)

    Ovarian 32P incorporation in hypophysectomized Heteropneustes fossilis in response to pituitary gland extract pooled from same species and mammalian gonadotropic preparations were studied. Maximum 32P uptake by ovary was obtained when a tracer dose of radiophosphorus was given 30 minutes after LH injection and fish were sacrificed 12 hours after the tracer shot. A log-dose response was observed between ovarian 32P uptake and gonadotropic content of pituitary extract or LH in hypophysectomized H. fossilis. This response was specific because FSH, TSH, prolactin and growth hormone injections failed to induce dose dependent and significant 32P uptake by ovary in similar assay recipients. However, FSH along with LH at higher dosage yielded an additive response. Also a parallelism of log-dose response was obtained between fish pituitary gonadotropin and ovine LH. Index of precision (Λ) was less than 0.214. Since donors and recipients were of the same species this bioassay of 12.5 hours for estimation of total gonadotropic potency seems to be rapid, reliable, sensitive and free from phylogenetic species specificity interaction between hormone and its receptor. (author)

  11. Multiple screening of medicinal plants from Oaxaca, Mexico: ethnobotany and bioassays as a basis for phytochemical investigation.

    Science.gov (United States)

    Frei, B; Heinrich, M; Bork, P M; Herrmann, D; Jaki, B; Kato, T; Kuhnt, M; Schmitt, J; Schühly, W; Volken, C; Sticher, O

    1998-05-01

    Based on ethnobotanical data collected among Zapotec Indians in Mexico, nine species traditionally applied to treat skin diseases and two species used to treat gastrointestinal disorders were subjected to several bioassays as further selection criteria for phytochemical investigation. Ten were active against at least one of the pathogenic and/or non-pathogenic bacteria and one against a non-pathogenic fungus in bioautographic TLC and agar diffusion tests. Cytotoxic/antitumor potential was found for one plant species with cell lines (KB, Caco-2) and for six with the brine shrimp assay. In the NF-κB- and the HET-CAM-test used to test for anti-inflammatory potential, two respectively one plant extract showed noteworthy activity. Furthermore, a potentially immunomodulating activity was investigated by evaluating the influence of extracts in various in vitro assays using murine and human lymphoid cells. In addition to the reported biological activities of the eleven plant species, comparisons of the ethnobotanical data and strategies for the selection for further phytochemical investigations are discussed. PMID:23195838

  12. Bioassay-Guided Isolation of DPP-4 Inhibitory Fractions from Extracts of Submerged Cultured of Inonotus obliquus

    Directory of Open Access Journals (Sweden)

    Jin-Song Shi

    2013-01-01

    Full Text Available Inonotus obliquus is a medicinal mushroom used in Russian and Eastern European folk medicine for the treatment of gastrointestinal cancer, cardiovascular disease and diabetes. Previous studies in our laboratory have demonstrated that the mycelium powders of I. obliquus possess significant antihyperglycemic effects in a mouse model of diabetic disease induced by alloxan. However, the active ingredients of mycelium powders responsible for the diabetes activity have not been identified. This study aims to identify the active ingredients of I. obliquus mycelium powders by a bioassay-guided fractionation approach and explore the mechanism of action of these active ingredients by using a well-established DPP-4 (an important enzyme as a new therapeutic target for diabetes inhibitory assay model. The results showed the chloroform extract of mycelium was potential inhibitory against DPP-4. Bioactivity guided fractionation led to the identification of 19 compounds using UPLC-Q-TOF-MS. Molecular docking between the compounds and DPP-4 revealed that compounds 5, 8, 9, 14, 15 may be the active components responsible for the DPP-4 inhibitory activity.

  13. Bioassay-guided isolation of DPP-4 inhibitory fractions from extracts of submerged cultured of Inonotus obliquus.

    Science.gov (United States)

    Geng, Yan; Lu, Zhen-Ming; Huang, Wei; Xu, Hong-Yu; Shi, Jin-Song; Xu, Zheng-Hong

    2013-01-01

    Inonotus obliquus is a medicinal mushroom used in Russian and Eastern European folk medicine for the treatment of gastrointestinal cancer, cardiovascular disease and diabetes. Previous studies in our laboratory have demonstrated that the mycelium powders of I. obliquus possess significant antihyperglycemic effects in a mouse model of diabetic disease induced by alloxan. However, the active ingredients of mycelium powders responsible for the diabetes activity have not been identified. This study aims to identify the active ingredients of I. obliquus mycelium powders by a bioassay-guided fractionation approach and explore the mechanism of action of these active ingredients by using a well-established DPP-4 (an important enzyme as a new therapeutic target for diabetes) inhibitory assay model. The results showed the chloroform extract of mycelium was potential inhibitory against DPP-4. Bioactivity guided fractionation led to the identification of 19 compounds using UPLC-Q-TOF-MS. Molecular docking between the compounds and DPP-4 revealed that compounds 5, 8, 9, 14, 15 may be the active components responsible for the DPP-4 inhibitory activity. PMID:23325103

  14. Evaluation of Membrane Stabilizing Activity, Total Phenolic Content, Brine Shrimp Lethality Bioassay, Thrombolytic and Antimicrobial Activities of Tagetes patula L.

    Directory of Open Access Journals (Sweden)

    Md. Ruhul Kuddus

    2012-11-01

    Full Text Available The methanol extract of leaf of Tagetes patula L. as well as its n-hexane, carbon tetrachloride, chloroform and aqueous soluble partitionates were subjected to screening for total phenolic content, brine shrimp lethality, membrane stabilizing, thrombolytic and antimicrobial activity. The membrane stabilizing activity was assessed by hypotonic solution-and heat-induced methods and was compared with acetyl salicylic acid. In the present studies, the n-hexane soluble fraction demonstrated strong membrane stabilizing activity in both hypotonic solution-and heat-induced methods with 44.48% and 42.68% inhibition of haemolysis, respectively. The total phenolic content was also determined and expressed in gallic acid equivalent. In brine shrimp bioassay, the crude methanol extract of leaf showed strong cytotoxic activity with LC50 value of 8.58 μg/ml compared to that of 0.451 μg/ml exhibited by standard vincristine sulphate. During assay for thrombolytic activity, the n-hexane soluble fraction revealed 43.7% lysis of clot while standard streptokinase and water, used as positive and negative controls, demonstrated 65.8% and 3.62% lysis of clot, respectively. In antimicrobial assay by disc diffusion method, all the samples exhibited moderate to significant antimicrobial activity (zone of inhibition = 9.0-22.0 mm against all the test organisms. Among all the samples, the carbon tetrachloride soluble fraction displayed strong antimicrobial activity against Escherichia coli (22.0 mm.

  15. Public Domain HTS Fingerprints: Design and Evaluation of Compound Bioactivity Profiles from PubChem's Bioassay Repository.

    Science.gov (United States)

    Helal, Kazi Yasin; Maciejewski, Mateusz; Gregori-Puigjané, Elisabet; Glick, Meir; Wassermann, Anne Mai

    2016-02-22

    Molecular profiling efforts aim at characterizing the biological actions of small molecules by screening them in hundreds of different biochemical and/or cell-based assays. Together, these assays yield a rich data landscape of target-based and phenotypic effects of the tested compounds. However, submitting an entire compound library to a molecular profiling panel can easily become cost-prohibitive. Here, we make use of historical screening assays to create comprehensive bioactivity profiles for more than 300 000 small molecules. These bioactivity profiles, termed PubChem high-throughput screening fingerprints (PubChem HTSFPs), report small molecule activities in 243 different PubChem bioassays. Although the assays originate from originally independently pursued drug or probe discovery projects, we demonstrate their value as molecular signatures when used in combination. We use these PubChem HTSFPs as molecular descriptors in hit expansion experiments for 33 different targets and phenotypes, showing that, on average, they lead to 27 times as many hits in a set of 1000 chosen molecules as a random screening subset of the same size (average ROC score: 0.82). Moreover, we demonstrate that PubChem HTSFPs retrieve hits that are structurally diverse and distinct from active compounds retrieved by chemical similarity-based hit expansion methods. PubChem HTSFPs are made freely available for the chemical biology research community. PMID:26898267

  16. Bioassay-guided isolation of proanthocyanidins with antioxidant activity from peanut (Arachis hypogaea) skin by combination of chromatography techniques.

    Science.gov (United States)

    Oldoni, Tatiane L C; Melo, Priscilla S; Massarioli, Adna P; Moreno, Ivani A M; Bezerra, Rosângela M N; Rosalen, Pedro L; da Silva, Gil V J; Nascimento, Andréa M; Alencar, Severino M

    2016-02-01

    Purification and bioassay-guided fractionation were employed to isolate proanthocyanidins with antioxidant activity from peanut skin (Arachis hypogaea Runner 886). The crude extract was prepared with acetone (60% v/v) and purified using chromatographic methods, including a semipreparative HPLC technique. As a result, two proanthocyanidins were isolated and identified using NMR, epicatechin-(2 β → O → 7, 4 β → 8)-catechin (proanthocyanidin A1) and epicatechin-(β → 2 O → 7, 4 β → 8)-epicatechin (proanthocyanidin A2). Despite the structural similarity, differences were observed in their antioxidant activity. Proanthocyanidin A1 proved to be more active, with EC50 value for DPPH radical scavenging of 18.25 μg/mL and reduction of Fe(3+)-TPTZ complex of 7.59 mmol/g, higher than that of synthetic antioxidant BHT. This compound evaluated by ABTS(+) was similar to that of natural quercetin. Therefore, peanut skin is an important source of bioactive compounds that may be used as a mild antioxidant for food preservation. PMID:26304352

  17. Preliminary characterization of extracellular allelochemicals of the toxic marine dinoflagellate Alexandrium tamarense using a Rhodomonas salina bioassay.

    Science.gov (United States)

    Ma, Haiyan; Krock, Bernd; Tillmann, Urban; Cembella, Allan

    2009-01-01

    Members of the marine dinoflagellate genus Alexandrium are known to exude allelochemicals, unrelated to well-known neurotoxins (PSP-toxins, spirolides), with negative effects on other phytoplankton and marine grazers. Physico/chemical characterization of extracellular lytic compounds of A. tamarense, quantified by Rhodomonas salina bioassay, showed that the lytic activity, and hence presumably the compounds were stable over wide ranges of temperatures and pH and were refractory to bacterial degradation. Two distinct lytic fractions were collected by reversed-phase solid-phase extraction. The more hydrophilic fraction accounted for about 2% of the whole lytic activity of the A. tamarense culture supernatant, while the less hydrophilic one accounted for about 98% of activity. Although temporal stability of the compounds is high, substantial losses were evident during purification. Lytic activity was best removed from aqueous phase with chloroform-methanol (3:1). A "pseudo-loss" of lytic activity in undisturbed and low-concentrated samples and high activity of an emulsion between aqueous and n-hexane phase after liquid-liquid partition are strong evidence for the presence of amphipathic compounds. Lytic activity in the early fraction of gel permeation chromatography and lack of activity after 5 kD ultrafiltration indicate that the lytic agents form large aggregates or macromolecular complexes. PMID:20098594

  18. Preliminary Characterization of Extracellular Allelochemicals of the Toxic Marine Dinoflagellate Alexandrium tamarense Using a Rhodomonas salina Bioassay

    Directory of Open Access Journals (Sweden)

    Allan Cembella

    2009-11-01

    Full Text Available Members of the marine dinoflagellate genus Alexandrium are known to exude allelochemicals, unrelated to well-known neurotoxins (PSP-toxins, spirolides, with negative effects on other phytoplankton and marine grazers. Physico/chemical characterization of extracellular lytic compounds of A. tamarense, quantified by Rhodomonas salina bioassay, showed that the lytic activity, and hence presumably the compounds were stable over wide ranges of temperatures and pH and were refractory to bacterial degradation. Two distinct lytic fractions were collected by reversed-phase solid-phase extraction. The more hydrophilic fraction accounted for about 2% of the whole lytic activity of the A. tamarense culture supernatant, while the less hydrophilic one accounted for about 98% of activity. Although temporal stability of the compounds is high, substantial losses were evident during purification. Lytic activity was best removed from aqueous phase with chloroform-methanol (3:1. A “pseudo-loss” of lytic activity in undisturbed and low-concentrated samples and high activity of an emulsion between aqueous and n-hexane phase after liquid-liquid partition are strong evidence for the presence of amphipathic compounds. Lytic activity in the early fraction of gel permeation chromatography and lack of activity after 5 kD ultrafiltration indicate that the lytic agents form large aggregates or macromolecular complexes.

  19. Determination of estrogenic activity in the river Chienti (Marche Region, Italy) by using in vivo and in vitro bioassays.

    Science.gov (United States)

    Cocci, Paolo; Palermo, Francesco Alessandro; Quassinti, Luana; Bramucci, Massimo; Miano, Antonino; Mosconi, Gilberto

    2016-05-01

    Environmental estrogen-like compounds (i.e. xenoestrogens) are a variety of pollutants, ranging from synthetic to natural occurring molecules, that are found in surface and waste waters over a wide range of concentrations. In aquatic environment, the overall estrogenic activity is often due to the presence of a mixture of chemicals and their degraded products which can induce synergistic effects. Current strategies for monitoring estrogen-like chemicals are based on the use of a battery of in vivo and in vitro ecotoxicological tests. In this regard, the aim of the present work was to carry out a bio-monitoring study for testing estrogenicity of the Chienti river (Marche Region, Italy) by using both an E-screen and a vitellogenin (Vtg) induction assay in juvenile goldfish. Three sites were used for analysis, localized at the mouth (sampling point 1), in the middle (sampling point 2) and at the origin (sampling point 3) of Chienti river. For most of the water samples (i.e. samples collected at sampling points 2 and 3), clear estrogenic activity was detected in the E-screen assay suggesting different proliferation activities in function of the collecting site. In contrast, the Vtg ELISA demonstrated that water samples collected from each sampling point were estrogenic. Overall, we showed for the first time that the estrogenic activities in water samples from the Chienti river were significant in both in vivo and in vitro; we also observed a different sensitivity between bioassays. PMID:27155408

  20. Evaluation of the Antiproliferative Activity of the Leaves from Arctium lappa by a Bioassay-Guided Fractionation

    Directory of Open Access Journals (Sweden)

    Celso Vataru Nakamura

    2012-02-01

    Full Text Available Arctium lappa L. (Asteraceae is used in folk medicine around the World, and shows several kinds of biological activity, particularly in vitro antitumor activity in different cell lines. This study evaluated the antiproliferative activity of the crude extract, semipurified fractions, and isolated compounds from the leaves of A. lappa, through bioassay-guided testing in Caco-2 cells. The crude extract was obtained with a 50% hydroethanolic extract and then partitioned with hexane, ethyl acetate, and n-butanol. The ethyl-acetate fraction (EAF showed antiproliferative activity. This fraction was subjected to sequential column chromatography over silica gel to afford onopordopicrin (1, mixtures of 1 with dehydromelitensin-8-(4'-hydroxymethacrylate (2, a mixture of 2 with dehydromelitensin (3, mixture of 1 with melitensin (4, dehydrovomifoliol (5, and loliolide (6. The compounds were identified by spectroscopic methods (NMR, MS and comparison with literature data. This is the first description of compounds 2–5 from this species. The compounds tested in Caco-2 cells showed the following CC50 (µg/mL values: 1: 19.7 ± 3.4, 1 with 2: 24.6 ± 1.5, 2 with 3: 27 ± 11.7, 1 with 4: 42 ± 13.1, 6 30 ± 6.2; compound 5 showed no activity.

  1. BIOASSAY-GUIDED FRACTIONATION AND ANTIHYPERTENSIVE PROPERTIES OF FRACTIONS AND CRUDE EXTRACTS OF PERISTROPHE BICALYCULATA (RETZ) NEES.

    Science.gov (United States)

    Abdulazeez, Mansurah A; Ibrahim, Sani; Ameh, Danladi A; Ameh, Danladi Amodu; Ayo, Joseph O; Carvalho, Luiz J C B; Manosroi, Jiradej; Ibrahim, Abdulrazak B

    2015-01-01

    Hypertension is an important public health issue in both developed and developing countries due to its high incidence and morbidity. This has motivated researchers especially in developing countries to search for strategies for the treatment using different plant parts. The use of the aqueous decoction of the leaves of Peristiophe bicalyculata in the treatment of hypertension has been documented. This study was designed to carry out a bioassay-guided isolation of the antihypertensive components of the leaves of Peristrophe bicalyculata in L-NAME hypertensive rats, determine the angiotensin-converting enzyme inhibitory activity of the extracts and fractions obtained and identify the constituent(s) present. From our results, L-NAME hypertensive rats given the cold water extract had significantly (p present work demonstrates the hypotensive effect of the cold water extract of Peiistiophe bicalyculata on L-NAME hypertensive rats, which further justifies the folkloric application of extracts of the plant in the management as well as treatment of hypertension. PMID:26642682

  2. Anti-bacterial activity and brine shrimp lethality bioassay of methanolic extracts of fourteen different edible vegetables from Bangladesh

    Institute of Scientific and Technical Information of China (English)

    MObayedUllah; MahmudaHaque; KanizFatimaUrmi; AbuHasanatMdZulfiker; ElicheaSynthiAnita; MomtajBegum; KaiserHamid

    2013-01-01

    Objective: To investigate the antibacterial and cytotoxic activity of fourteen different edible vegetables methanolic extract from Bangladesh. Methods: The antibacterial activity was evaluated using disc diffusion assay method against 12 bacteria (both gram positive and gram negative). The plant extracts were also screened for cytotoxic activity using the brine shrimp lethality bioassay method and the lethal concentrations (LC50) were determined at 95% confidence intervals by analyzing the data on a computer loaded with “Finney Programme”. Results: All the vegetable extracts showed low to elevated levels of antibacterial activity against most of the tested strains (zone of inhibition=5-28 mm). The most active extract against all bacterial strains was from Xanthium indicum which showed remarkable antibacterial activity having the diameter of growth inhibition zone ranging from 12 to 28 mm followed by Alternanthera sessilis (zone of inhibition=6-21 mm). All extracts exhibited considerable general toxicity towards brine shrimps. The LC50 value of the tested extracts was within the range of 8.447 to 60.323 µg/mL with respect to the positive control (vincristine sulphate) which was 0.91 µg/mL. Among all studied extracts, Xanthium indicum displayed the highest cytotoxic effect with LC50 value of 8.447 µg/mL. Conclusions: The results of the present investigation suggest that most of the studied plants are potentially good source of antibacterial and anticancer agents.

  3. Anti-bacterial activity and brine shrimp lethality bioassay of methanolic extracts of fourteen different edible vegetables from Bangladesh

    Institute of Scientific and Technical Information of China (English)

    M.Obayed; Ullah; Mahmuda; Haque; Kaniz; Fatima; Urmi; Abu; Hasanat; Md.Zulfiker; Elichea; Synthi; Anita; Momtaj; Begum; Kaiser; Hamid

    2013-01-01

    Objective:To investigate the antibacterial and cytotoxic activity of fourteen different edible vegetables methanolic extract from Bangladesh.Methods:The antibacterial activity was evaluated using disc diffusion assay method against 12 bacteria(both gram positive and gram negative).The plant extracts were also screened for cytotoxic activity using the brine shrimp lethality bioassay method and the lethal concentrations(LC50)were determined at confidence intervals by analyzing the data on a computer loaded with"Finney Programme??Results:All the vegetable extracts showed low to elevated levels of antibacterial activity against most of the tested strains(zone of inhibition=5-28 mm).The most active extract against all bacterial strains was from Xanthium indicum which showed remarkable antibacterial activity having the diameter of growth inhibition zone ranging from 12 to 28 mm followed by Alternanthera sessilis(zone of inhibition=6-21 mm).All extracts exhibited considerable general toxicity towards brine shrimps.The LC50value of the tested extracts was within the range of 8.447 to 60.323μg/mL with respect to the positive control(vincristine sulphate)which was 0.91μg/mL.Among all studied extracts,Xanthium indicum displayed the highest cytotoxic effect with LC50value of 8.447μg/mL.Conclusions:The results of the present investigation suggest that most of the studied plants are potentially good source of antibacterial and anticancer agents.

  4. Development of a chronic sublethal bioassay for evaluating contaminated sediment with the marine polychaete worm Nereis (Neanthes) arenaceodentata

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, T.M.; Moore, D.W.; Gibson, A.B. (Army Engineer Waterways Experiment Station, Vicksburg, MS (United States))

    1993-03-01

    Development of a chronic sublethal sediment bioassay with the polychaete Nereis (Neanthes) arenaceodentata is described. The sublethal test end point was estimated individual somatic growth rate. The test was initiated with two-to three-week-old post-emergent juvenile worms and continued for 28 d. The potential bias due to selected nontreatment factors on polychaete survival and growth was evaluated. For example, grain size has no significant effect, whereas the number of worms placed in each exposure vessel was critical. Direct transfer from 30[per thousand] seawater to salinites [<=] 15[per thousand] had a highly significant and adverse effect on survival and growth. Both survival and growth of juvenile worms may be adversely affected if test conditions involve exposures to [>=] 0.7 mg/L un-ionized ammonia or [>=] 5 mg/L hydrogen sulfide. Survival of juvenile worms to concentrations of the reference toxicant, cadmium chloride, approximating the 96-h LC50 (5 mg/L) was used as a quality control measure. Results are expressed in control chart format analogous to methods used in analytical chemistry.

  5. Development of a radioimmunoassay for Escherichia coli heat-stable enterotoxin: comparison with the suckling mouse bioassay

    International Nuclear Information System (INIS)

    Escherichia coli strains which produce heat-stable enterotoxin (ST) are usually identified by demonstrating the production of ST. At present, ST can be detected only by bioassay methods. Recently, we purified E. coli ST, which enabled us to develop a radioimmunoassay for ST. Radioiodination of ST was performed by the lactoperoxidase method, which resulted in a high specific activity and retained the biological activity of St. Anti-ST antisera were raised in goats by injecting the goats with pure ST coupled to bovine immunoglobin G. Antibody titers ranged from 1:8,000 to 1:40,000. Using these reagents, we examined assay conditions thoroughly and found that a 14- to 18-h incubation at 4 degrees C in sodium acetate buffer with an ionic strength of 120 mM (pH 6.2) gave maximal sensitivity and reproducibility. Free ST was separated from antibody-bound ST by dextran-coated charcoal. This radioimmunoassay accurately and reproducibly measured ST in the range from 50 to 500 pg of ST per tube and could quantitate ST accurately in complex bacteriological media. This assay was specific for STa, measured human and porcine STa equally well, and did not cross-react with STb, with several other enterotoxins, or with various gastrointestinal peptides. Intact disulfide bridges in the ST molecule were required for immunoreactive activity

  6. Radiomutagenesis and an in vitro conductimetric bioassay: it's application to avocado improvement for Phytophthora spp. resistance

    International Nuclear Information System (INIS)

    Avocado root-rot, caused by Phytophtora cinnamomi is among the main biotic stresses causing important economic losses to the crop. Therefore, development and identification of new genotypes resistant to the pathogen is important for an integrated disease management. However, limitations to avocado breeding and production are also related to the long juvenile period, large cultivation areas and extensive natural cross-pollination. In this sense, radiomutagenesis has proven to be a valuable tool to improve disease resistance in fruit trees. For this, the determination of mutagenic doses, combined with in vitro selection and conductimetric bioassays are necessary to accelerate the mutation breeding schemes. In avocado, the measurement of electrical conductivity, based on the release of microelectrolytes to the medium due to cell permeability damage, has been performed on inoculated roots and leaves. In the present work is showed a report of mutagenic doses against gamma rays (LD50 and LD20) determined for in vitro propagated zygotic embryos of three avocado cultivars. Additionally, electric conductivity was measured in leaf discs and root segments from zygotic embryos of Catalina cv. challenged with culture filtrates of isolates from different regions of the country. The results indicated a differential response of the genotype depending on the strain used. Also, differential response was observed, depending on tissue type

  7. Over-simplification and over-standardization in biological methods: Sperm bioassays in eco-toxicology as a case of study, and a proposal for their reformulation

    OpenAIRE

    Murado García, Miguel Anxo; Prieto, Miguel Ángel

    2014-01-01

    An interesting toxicological bioassay (fertilization inhibition in sea urchin) uses as assessment criterion a variable (fertilization ratio) whose variation with time creates two types of difficulties. First, it fails to distinguish between the toxic effect and the spontaneous decline in the sperm activity, causing some inconsistencies. Second, the sensitivity of the fertilization ratio to many other variables of the system requires a complex standardization, constraining the achievement of t...

  8. Potency determination of follitropin, lutropin And thyrotropin: a comparison between the quantification by reversed-phase high-performance liquid chromatography and in vivo bioassay

    International Nuclear Information System (INIS)

    With the intention of setting up physico-chemical methods as an alternative to in vivo bioassay for determining biological activity, the hFSH, hTSH and hLH content of native and recombinant preparations was determined by reversed-phase high-performance liquid chromatography (RP-HPLC) and compared with the data obtained by the classical mouse or rat in vivo bioassays (BA). A linear relationship between the two methods was found for these hormones: hFSH BAU= 0.9925 RP-HPLCU– 1.3165, r = 0.9371, p IU = 0.8771 RP-HPLCIU + 12.41, r = 0.9786, p < 0.01, n = 5. For nine other hFSH and eleven hTSH preparations, the mean difference ( ) between the bioactivity predicted from RP-HPLC data via these equations and the mean of the bioactivities obtained with the two methods was as follows. For hLH this difference could not be estimated due to lack of different samples. In the case of hFSH, ± SD = -2.11 ± 3.49% with a precision of 1.16% and in the case of hTSH, ± SD = -2.01 ± 5.56 %, with precision of 1.68%. Partly-degraded hFSH, hTSH and hLH samples presented different activity degrees that could be predicted by RP-HPLC, with an acceptable agreement with the in vivo bioassays. These results demonstrate that the employment of a non-animal physico-chemical assay, such as RP-HPLC, is a viable alternative to the use of an in vivo bioassay for hFSH and hTSH potency determination, thus reducing the number of animals currently used for assuring quality and efficacy of a pharmaceutical product. (author)

  9. Bioassay-Guided Fractionation of Extracts from Codiaeum variegatum against Entamoeba histolytica Discovers Compounds That Modify Expression of Ceramide Biosynthesis Related Genes

    OpenAIRE

    Emmanuel Mfotie Njoya; Christian Weber; Nora Adriana Hernandez-Cuevas; Chung-Chau Hon; Yves Janin; Kamini, Melanie F G; Moundipa, Paul F; Nancy Guillén

    2014-01-01

    International audience Leaves of Codiaeum variegatum ("garden croton") are used against bloody diarrhoea by local populations in Cameroon. This study aims to search for the active components from C. variegatum against Entamoeba histolytica, and thereby initiate the study of their mechanism of action. A bioassay-guided screening of the aqueous extracts from C. variegatum leaves and various fractions was carried out against trophozoites of E. histolytica axenic culture. We found that the ant...

  10. Thyroid-stimulating immunoglobulins as measured in a reporter bioassay are not detected in patients with Hashimoto’s thyroiditis and ophthalmopathy or isolated upper eyelid retraction

    OpenAIRE

    Wall, Jack R; Lahooti, Hooshang; El Kochairi, Ilhem; Lytton, Simon D; Champion, Bernard

    2014-01-01

    Although ophthalmopathy is mainly associated with Graves’ hyperthyroidism, milder eye changes are also found in about 25% of patients with Hashimoto’s thyroiditis (HT). The recent finding of negative thyrotropin receptor (TSHR) antibodies, as measured in the Thyretain™ thyroid-stimulating immunoglobulin (TSI) reporter bioassay, in patients with euthyroid Graves’ disease raises the possibility that TSHR antibodies are not the cause of ophthalmopathy in all situations. Here, we have tested seru...

  11. Gamma-interferon bioassay for detection of bovine tuberculosis in cattle: kinetics of production and dose response in whole blood culture

    International Nuclear Information System (INIS)

    Stimulation with mycobacterium bovis PPD sensitised lymphocytes (whole blood or peripheral blood lymphocytes) results in release of gamma-interferon that can be detected by simple bioassay. The optimum concentration of bovine PPD was 20 μg ml and the optimum incubation period was 24 hr for maximum production of gamma-interferon in whole blood culture (128 units/ml) and peripheral blood culture (64 units/ml). (author)

  12. Bioassay-guided studies on the cytotoxic and in vitro trypanocidal activities of a sesquiterpene (Muzigadial) derived from a Ugandan medicinal plant (Warburgia ugandensis)

    OpenAIRE

    Olila, D; Opuda-Asibo, J; Olwa-Odyek,

    2001-01-01

    Trypanosomiasis is arguably the most important disease of man and his domesticated animals in the tropics. There are few compounds available for its treatment. This has exacerbated the development of drug resistance. There is therefore urgent need to search for newer compounds to treat this important disease. Medicinal plants represent a potential source of the drugs. This paper reports a bioassay-guided study to search for possible biological activity (cytotoxic and trypanocidal) in two Ugan...

  13. Bioassay-Guided Fractionation of Extracts from Codiaeum variegatum against Entamoeba histolytica Discovers Compounds That Modify Expression of Ceramide Biosynthesis Related Genes.

    OpenAIRE

    Mfotie Njoya, Emmanuel; Weber, Christian; Hernandez-Cuevas, Nora Adriana; Hon, Chung-Chau; Janin, Yves; Kamini, Melanie F G; Moundipa, Paul F.; Guillén, Nancy

    2014-01-01

    Leaves of Codiaeum variegatum ("garden croton") are used against bloody diarrhoea by local populations in Cameroon. This study aims to search for the active components from C. variegatum against Entamoeba histolytica, and thereby initiate the study of their mechanism of action. A bioassay-guided screening of the aqueous extracts from C. variegatum leaves and various fractions was carried out against trophozoites of E. histolytica axenic culture. We found that the anti-amoebic activity of extr...

  14. Comparative evaluation of acute toxicity by Vibrio fischeri and fern spore based bioassays in the follow-up of toxic chemicals degradation by photocatalysis.

    Science.gov (United States)

    Marugán, Javier; Bru, David; Pablos, Cristina; Catalá, Myriam

    2012-04-30

    The development of efficient bioassays is a necessary step for cost-effective environmental monitoring and evaluation of novel decontamination technologies. Marine Vibrio fischeri kits have demonstrated to be extremely sensitive but lack of ecological relevance, especially when assessing impacts on freshwater higher organisms. A novel riparian are fern spore microbioassay could merge higher ecological relevance and reduced costs. The aim of this work is the comparative evaluation of the V. fischeri and fern spore bioassays for the follow up of detoxification processes of water contaminated with cyanide and phenol by advanced oxidation technologies, using heterogeneous photocatalysis as example. In both cases, EC(50) values differed significantly for V. fischeri commercial kit, V. fischeri lab cultures and Polystichum setiferum fern spores (1.9, 16 and 101 mg cyanide L(-1) and 27.0, 49.3 and 1440 mg phenol L(-1), respectively). Whereas V. fischeri bioassays are extremely sensitive and dilution series must be prepared, toxicant solutions can be directly applied to spores. Spore microbioassay was also useful in the follow up of photoxidation processes of cyanide and phenol, also reflecting the formation of intermediate degradation by-products even more toxic than phenol. We conclude that this new microbioassay is a promising cost-effective tool for the follow up of decontamination processes. PMID:22341980

  15. The apoptosis-inducing activity towards leukemia and lymphoma cells in a cyanobacterial culture collection is not associated with mouse bioassay toxicity.

    Science.gov (United States)

    Oftedal, Linn; Skjærven, Kaja H; Coyne, Rosie T; Edvardsen, Bente; Rohrlack, Thomas; Skulberg, Olav M; Døskeland, Stein Ove; Herfindal, Lars

    2011-04-01

    Cyanobacteria (83 strains and seven natural populations) were screened for content of apoptosis (cell death)-inducing activity towards neoplastic cells of the immune (jurkat acute T-cell lymphoma) and hematopoetic (acute myelogenic leukemia) lineage. Apoptogenic activity was frequent, even in strains cultured for decades, and was unrelated to whether the cyanobacteria had been collected from polar, temperate, or tropic environments. The activity was more abundant in the genera Anabaena and Microcystis compared to Nostoc, Phormidium, Planktothrix, and Pseudanabaena. Whereas the T-cell lymphoma apoptogens were frequent in organic extracts, the cell death-inducing activity towards leukemia cells resided mainly in aqueous extracts. The cyanobacteria were from a culture collection established for public health purposes to detect toxic cyanobacterial blooms, and 54 of them were tested for toxicity by the mouse bioassay. We found no correlation between the apoptogenic activity in the cyanobacterial isolates with their content of microcystin, nor with their ability to elicit a positive standard mouse bioassay. Several strains produced more than one apoptogen, differing in biophysical or biological activity. In fact, two strains contained microcystin in addition to one apoptogen specific for the AML cells, and one apoptogen specific for the T-cell lymphoma. This study shows the potential of cyanobacterial culture collections as libraries for bioactive compounds, since strains kept in cultures for decades produced apoptogens unrelated to the mouse bioassay detectable bloom-associated toxins. PMID:20689978

  16. Calibrating Self-Reported Measures of Maternal Smoking in Pregnancy via Bioassays Using a Monte Carlo Approach

    Directory of Open Access Journals (Sweden)

    Lauren S. Wakschlag

    2009-06-01

    Full Text Available Maternal smoking during pregnancy is a major public health problem that has been associated with numerous short- and long-term adverse health outcomes in offspring. However, characterizing smoking exposure during pregnancy precisely has been rather difficult: self-reported measures of smoking often suffer from recall bias, deliberate misreporting, and selective non-disclosure, while single bioassay measures of nicotine metabolites only reflect recent smoking history and cannot capture the fluctuating and complex patterns of varying exposure of the fetus. Recently, Dukic et al. [1] have proposed a statistical method for combining information from both sources in order to increase the precision of the exposure measurement and power to detect more subtle effects of smoking. In this paper, we extend the Dukic et al. [1] method to incorporate individual variation of the metabolic parameters (such as clearance rates into the calibration model of smoking exposure during pregnancy. We apply the new method to the Family Health and Development Project (FHDP, a small convenience sample of 96 predominantly working-class white pregnant women oversampled for smoking. We find that, on average, misreporters smoke 7.5 cigarettes more than what they report to smoke, with about one third underreporting by 1.5, one third under-reporting by about 6.5, and one third underreporting by 8.5 cigarettes. Partly due to the limited demographic heterogeneity in the FHDP sample, the results are similar to those obtained by the deterministic calibration model, whose adjustments were slightly lower (by 0.5 cigarettes on average. The new results are also, as expected, less sensitive to assumed values of cotinine half-life.

  17. Identification of a Peripheral Nerve Neurite Growth-Promoting Activity by Development and Use of an in vitro Bioassay

    Science.gov (United States)

    Sandrock, Alfred W.; Matthew, William D.

    1987-10-01

    The effective regeneration of severed neuronal axons in the peripheral nerves of adult mammals may be explained by the presence of molecules in situ that promote the effective elongation of neurites. The absence of such molecules in the central nervous system of these animals may underlie the relative inability of axons to regenerate in this tissue after injury. In an effort to identify neurite growth-promoting molecules in tissues that support effective axonal regeneration, we have developed an in vitro bioassay that is sensitive to substrate-bound factors of peripheral nerve that influence the growth of neurites. In this assay, neonatal rat superior cervical ganglion explants are placed on longitudinal cryostat sections of fresh-frozen sciatic nerve, and the regrowing axons are visualized by catecholamine histofluorescence. Axons are found to regenerate effectively over sciatic nerve tissue sections. When ganglia are similarly explanted onto cryostat sections of adult rat central nervous system tissue, however, axonal regeneration is virtually absent. We have begun to identify the molecules in peripheral nerve that promote effective axonal regeneration by examining the effect of antibodies that interfere with the activity of previously described neurite growth-promoting factors. Axonal elongation over sciatic nerve tissue was found to be sensitive to the inhibitory effects of INO (for inhibitor of neurite outgrowth), a monoclonal antibody that recognizes and inhibits a neurite growth-promoting activity from PC-12 cell-conditioned medium. The INO antigen appears to be a molecular complex of laminin and heparan sulfate proteoglycan. In contrast, a rabbit antiserum that recognizes laminin purified from mouse Engelbreth-Holm-Swarm (EHS) sarcoma, stains the Schwann cell basal lamina of peripheral nerve, and inhibits neurite growth over purified laminin substrata has no detectable effect on the rate of axonal regeneration in our assay.

  18. Effect of iodination on human growth hormone and prolactin: characterized by bioassay, radioimmunoassay, radioreceptor assay, and electrophoresis

    International Nuclear Information System (INIS)

    Human GH (hGH) and PRL (hPRL) were iodinated using lactoperoxidase. The iodinated hormones were characterized by RIA, radioreceptor assay (RRA), and bioassay (BA) using the Nb2 Node lymphoma cell line. The proportion of tracer that could bind to rat liver membranes or rabbit antibodies was determined, and the distribution of iodinated hormones was examined using polyacrylamide gel electrophoresis. Excess antibody was capable of precipitating 87.9% of the radioactivity associated with the hGH tracer and 86.0% of the hPRL tracer. The maximal specific binding to a liver membrane preparation averaged 67.3% of the [125I]iodo-hGH radioactivity and 48.8% of the [125I]iodo-hPRL radioactivity. The respective BA and RRA activity estimates for [125]iodo-hGH averaged 90% and 114% of the activity measured by the RIA. For [125I]iodo-hPRL, the values were 75% by BA and 68% by RRA. The bioactivity profiles of iodinated hGH and hPRL shifted anodally on polyacrylamide gel electrophoresis in comparison to the bioactivity distribution of the respective uniodinated hormones. Iodine incorporation rather than oxidation appeared to be responsible for the shift. After electrophoresis, all eluates which contained significant radioactivity were active in the BA and RIA. Furthermore, specific activities calculated from the bioactive hormone and radioactivity in each electrophoretic segment agreed well with the average specific activity estimated from the amount of iodine incorporated into the protein peak upon gel filtration. These data suggest that hGH and hPRL to a major degree retain biological integrity after iodination

  19. Expression Patterns of Cancer Stem Cell Markers During Specific Celecoxib Therapy in Multistep Rat Colon Carcinogenesis Bioassays.

    Science.gov (United States)

    Salim, Elsayed I; Hegazi, Mona M; Kang, Jin Seok; Helmy, Hager M

    2016-01-01

    The purpose of this study was to investigate the role of colon cancer stem cells (CSCs) during chemicallyinduced rat multi-step colon carcinogenesis with or without the treatment with a specific cyclooxygenase-2 inhibitor drug (celecoxib). Two experiments were performed, the first, a short term 12 week colon carcinogenesis bioassay in which only surrogate markers for colon cancer, aberrant crypt foci (ACF) lesions, were formed. The other experiment was a medium term colon cancer rat assay in which tumors had developed after 32 weeks. Treatment with celecoxib lowered the numbers of ACF, as well as the tumor volumes and multiplicities after 32 weeks. Immunohistochemical proliferating cell nuclear antigen (PCNA) labeling indexes LI (%) were downregulated after treatment by celecoxib. Also different cell surface antigens known to associate with CSCs such as the epithelial cell adhesion molecule (EpCAM), CD44 and CD133 were compared between the two experiments and showed differential expression patterns depending on the stage of carcinogenesis and treatment with celecoxib. Flow cytometric analysis demonstrated that the numbers of CD133 cells were increased in the colonic epithelium after 12 weeks while those of CD44 but not CD133 cells were increased after 32 weeks. Moreover, aldehyde dehydrogenase-1 activity levels in the colonic epithelium (a known CSC marker) detected by ELISA assay were found down-regulated after 12 weeks, but were up-regulated after 32 weeks. The data have also shown that the protective effect of celecoxib on these specific markers and populations of CSCs and on other molecular processes such as apoptosis targeted by this drug may vary depending on the genetic and phenotypic stages of carcinogenesis. Therefore, uncovering these distinction roles of CSCs during different phases of carcinogenesis and during specific treatment could be useful for targeted therapy. PMID:27039721

  20. Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

    Science.gov (United States)

    Manríquez, Patricio H; Llanos-Rivera, Alejandra; Galaz, Sylvana; Camaño, Andrés

    2013-12-01

    The Chilean abalone or "loco" (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. PMID:24099753

  1. Formalization, annotation and analysis of diverse drug and probe screening assay datasets using the BioAssay Ontology (BAO.

    Directory of Open Access Journals (Sweden)

    Uma D Vempati

    Full Text Available Huge amounts of high-throughput screening (HTS data for probe and drug development projects are being generated in the pharmaceutical industry and more recently in the public sector. The resulting experimental datasets are increasingly being disseminated via publically accessible repositories. However, existing repositories lack sufficient metadata to describe the experiments and are often difficult to navigate by non-experts. The lack of standardized descriptions and semantics of biological assays and screening results hinder targeted data retrieval, integration, aggregation, and analyses across different HTS datasets, for example to infer mechanisms of action of small molecule perturbagens. To address these limitations, we created the BioAssay Ontology (BAO. BAO has been developed with a focus on data integration and analysis enabling the classification of assays and screening results by concepts that relate to format, assay design, technology, target, and endpoint. Previously, we reported on the higher-level design of BAO and on the semantic querying capabilities offered by the ontology-indexed triple store of HTS data. Here, we report on our detailed design, annotation pipeline, substantially enlarged annotation knowledgebase, and analysis results. We used BAO to annotate assays from the largest public HTS data repository, PubChem, and demonstrate its utility to categorize and analyze diverse HTS results from numerous experiments. BAO is publically available from the NCBO BioPortal at http://bioportal.bioontology.org/ontologies/1533. BAO provides controlled terminology and uniform scope to report probe and drug discovery screening assays and results. BAO leverages description logic to formalize the domain knowledge and facilitate the semantic integration with diverse other resources. As a consequence, BAO offers the potential to infer new knowledge from a corpus of assay results, for example molecular mechanisms of action of perturbagens.

  2. Use of plant bioassays in homeopathic basic research – a systematic review

    Directory of Open Access Journals (Sweden)

    Ursula Wolf

    2012-09-01

    Full Text Available Background: Experimental research on the effects of treatments with homeopathic preparations on plants was last reviewed in 1990. Aims: The objective was to compile a systematic literature review on plant bioassays in homeopathic basic research using predefined criteria. Methods: Literature search was carried out on publications that reported experiments with homeopathic preparations on whole plants, seeds, plant parts or cells from 1920 to 2010, in healthy, abiotically or biotically stressed conditions. Outcomes had to be measured by established state-of-the-art procedures and statistically evaluated. Using a Manuscript Information Score (MIS those publications were identified that provided sufficient information for proper interpretation (MIS > 5. Further evaluation focused on the use of adequate controls to investigate specific effects of homeopathic preparations and on the use of systematic negative control experiments to ensure proper system performance. Results: A total of 157 publications with plants were identified [1–3]. The 157 publications described a total of 167 experimental studies. 84 studies included statistics and 48 had a MIS > 5 allowing proper interpretation. 29 studies were identified with adequate controls to identify specific effects of homeopathic preparations, reporting significant effects of decimal and centesimal homeopathic potencies, including dilution levels beyond Avogadro’s number. Studies that tested series of consecutive potency levels reported a non-linear and discontinuous relation between effect and potency level. There were many individual studies with diverse methods and very few replication trials. 10 studies reported use of systematic negative control experiments, yielding evidence for the stability of the experimental set-up. Conclusions: Plant models appear to be a useful approach to investigate basic research questions on

  3. Bioassay-guided discovery of antibacterial agents: in vitro screening of Peperomia vulcanica, Peperomia fernandopoioana and Scleria striatinux

    Directory of Open Access Journals (Sweden)

    Mbah James A

    2012-05-01

    Full Text Available Abstract Background The global burden of bacterial infections is high and has been further aggravated by increasing resistance to antibiotics. In the search for novel antibacterials, three medicinal plants: Peperomia vulcanica, Peperomia fernandopoioana (Piperaceae and Scleria striatinux (Cyperaceae, were investigated for antibacterial activity and toxicity. Methods Crude extracts of these plants were tested by the disc diffusion method against six bacterial test organisms followed by bio-assay guided fractionation, isolation and testing of pure compounds. The minimum inhibitory (MIC and minimum bactericidal (MBC concentrations were measured by the microdilution method. The acute toxicity of the active extracts and cytotoxicity of the active compound were performed in mice and mammalian cells, respectively. Results The diameter of the zones of inhibition (DZI of the extracts ranged from 7–13 mm on Escherichia coli and Staphylococcus aureus of which the methylene chloride:methanol [1:1] extract of Scleria striatinux recorded the highest activity (DZI = 13 mm. Twenty-nine pure compounds were screened and one, Okundoperoxide, isolated from S. striatinux, recorded a DZI ranging from 10–19 mm on S. aureus. The MICs and MBCs indicated that the Peperomias had broad-spectrum bacteriostatic activity. Toxicity tests showed that Okundoperoxide may have a low risk of toxicity with an LC50 of 46.88 μg/mL. Conclusions The antibacterial activity of these plants supports their use in traditional medicine. The pure compound, Okundoperoxide, may yield new antibacterial lead compounds following medicinal chemistry exploration.

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

    Science.gov (United States)

    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. PMID:26845705

  5. Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, N. [New York Univ. Medical Center, Tuxedo, NY (United States). Dept. of Environmental Medicine

    1989-03-15

    A Polonium metabolic model was derived and incorporated into a Fortran algorithm which estimates the systemic radiation dose from {sup 210}Po when applied to occupational urine bioassay data. The significance of the doses estimated are examined by defining the degree of uncertainty attached to them through comprehensive statistical testing procedures. Many parameters necessary for dosimetry calculations (such as organ partition coefficients and excretion fractions), were evaluated from metabolic studies of {sup 210}Po in non-human primates. Two tamarins and six baboons were injected intravenously with {sup 210}Po citrate. Excreta and blood samples were collected. Five of the baboons were sacrificed at times ranging from 1 day to 3 months post exposure. Complete necropsies were performed and all excreta and the majority of all skeletal and tissue samples were analyzed radiochemically for their {sup 210}Po content. The {sup 210}Po excretion rate in the baboon was more rapid than in the tamarin. The biological half-time of {sup 210}Po excretion in the baboon was approximately 15 days while in the tamarin, the {sup 210}Po excretion rate was in close agreement with the 50 day biological half-time predicted by ICRP 30. Excretion fractions of {sup 210}Po in the non-human primates were found to be markedly different from data reported elsewhere in other species, including man. A thorough review of the Po urinalysis procedure showed that significant recovery losses resulted when metabolized {sup 210}Po was deposited out of raw urine. Polonium-210 was found throughout the soft tissues of the baboon but not with the partition coefficients for liver, kidneys, and spleen that are predicted by the ICRP 30 metabolic model. A fractional distribution of 0.29 for liver, 0.07 for kidneys, and 0.006 for spleen was determined. Retention times for {sup 210}Po in tissues are described by single exponential functions with biological half-times ranging from 15 to 50 days.

  6. Laboratory Bioassay of Iranian Isolates of Entomopathogenic Fungus Metarhizium anisopliae (Metsch. Sorokin (Ascomycota: Hypocreales against two Species of Storage Pest

    Directory of Open Access Journals (Sweden)

    Hamid Sakenin Chelav

    2013-03-01

    Full Text Available The susceptibility of adults of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae and Oryzaephilus surinamensis L. (Coleoptera: Silvanidae to three Iranian Isolates of the entomopathogenic fungi Metarhizium anisopliae (Metsch. Sorokin was evaluated through bioassays with direct immersion under laboratory conditions. For each isolates, five aqueous suspensions were prepared in a logarithmic series in Tween 80 (0.05% v/v. Results showed that adult of both species were susceptible to all isolates of M. anisopliae. For all three isolates, mortality percentage of the two species increased with increasing conidial concentration and significant difference was observed between concentrations. The corrected cumulative mortality of adult of O. surinamensis 10 days after immersion ranged from 12.38 to 85.84%, 18.6 to 62.83% and 10.63 to 77.87% for different concentrations of DEMI001, IRAN 715C and IRAN 1018C, respectively. These amounts for T. castaneum varied from 31.07 to 74.78%, 26.02 to 75.61% and 23.33 to 89.99% for different concentrations of DEMI001, IRAN 715C and IRAN 1018C, respectively. The parameters of probit analysis demonstrated non-overlap of 95% confidence limits of LC50 and LC95 and significant difference was observed among three isolates tested against each insect. The lowest and the highest LC50 and LC95 values were observed in the isolates DEMI001 for O. surinamensis (3/1×105 and 1/5×108 and IRAN 715C for T. castaneum (6.2×108 and 6.9×1014, respectively. This observation highlights the importance and need of screening for more virulent isolates against storage pests for use in the management of these pests.

  7. Low cost quantitative digital imaging as an alternative to qualitative in vivo bioassays for analysis of active aflatoxin B1.

    Science.gov (United States)

    Rasooly, Reuven; Do, Paula M; Hernlem, Bradley J

    2016-06-15

    Aflatoxin B1 (AFB1) producing fungi contaminate food and feed and are a major health concern. To minimize the sources and incidence of AFB1 illness there is a need to develop affordable, sensitive mobile devices for detection of active AFB1. In the present study we used a low cost fluorescence detector and describe two quantitative assays for detection of detoxified and active AFB1 demonstrating that AFB1 concentration can be measured as intensity of fluorescence. When the assay plate containing increasing concentrations of AFB1 is illuminated with a 366nm ultraviolet lamp, AFB1 molecules absorb photons and emit blue light with peak wavelength of 432nm. The fluorescence intensity increased in dose dependent manner. However, this method cannot distinguish between active AFB1 which poses a threat to health, and the detoxified AFB1 which exhibits no toxicity. To measure the toxin activity, we used a cell based assay that makes quantification more robust and is capable of detecting multiple samples simultaneously. It is an alternative to the qualitative duckling bioassay which is the "gold-standard" assay currently being used for quantitative analysis of active AFB1. AFB1 was incubated with transduced Vero cells expressing the green fluorescence protein (GFP) gene. After excitation with blue light at 475nm, cells emitted green light with emission peak at 509nm. The result shows that AFB1 inhibits protein expression in a concentration dependent manner resulting in proportionately less GFP fluorescence in cells exposed to AFB1. The result also indicates strong positive linear relationship with R(2)=0.90 between the low cost CCD camera and a fluorometer, which costs 100 times more than a CCD camera. This new analytical method for measuring active AFB1 is low in cost and combined with in vitro assay, is quantitative. It also does not require the use of animals and may be useful especially for laboratories in regions with limited resources. PMID:26874107

  8. Thyroid disruption in male goldfish (Carassius auratus) exposed to leachate from a municipal waste treatment plant: Assessment combining chemical analysis and in vivo bioassay.

    Science.gov (United States)

    Gong, Yufeng; Tian, Hua; Dong, Yifei; Zhang, Xiaona; Wang, Jun; Wang, Wei; Ru, Shaoguo

    2016-06-01

    Several classes of thyroid-disrupting chemicals (TDCs) have been found in refuse leachate, but the potential impacts of leachate on the thyroid cascade of aquatic organisms are yet not known. In this study, we chemically analyzed frequently reported TDCs, as well as conducted a bioassay, to evaluate the potential thyroid-disrupting effects of leachate. We used radioimmunoassay to determine the effects of leachate exposure on plasma 3,3',5-triiodo-l-thyronine (T3), 3,3',5,5'-l-thyroxine (T4), and thyroid-stimulating hormone (TSH) levels in adult male goldfish (Carassius auratus). We also investigated the impacts of leachate treatment on hepatic and gonadal deiodinases [types I (D1), II (D2), and III (D3)] and gonadal thyroid receptor (TRα-1 and TRβ) mRNA expressions by using real-time polymerase chain reaction. The results indicated the presence of five TDCs (bisphenol A, 4-t-octylphenol, di-n-butyl phthalate, di-n-octyl phthalate, and diethylhexyl phthalate); their mean concentrations in the leachate were 18.11, 2.76, 4.86, 0.21, and 9.16μg/L, respectively. Leachate exposure induced plasma T3 and TSH levels in male fish, without influencing the plasma T4 levels. The highly elevated D2 mRNA levels in the liver were speculated to be the primary reason for the induction of plasma T3 levels. Disruption of thyroid functions by leachate was also suggested by the up-regulation of D1 and D2 as well as TRα-1 mRNA levels in the gonads. Prominent thyroid disruptions despite the very low TDC concentrations in the exposure media used in the bioassay strongly indicated the existence of unidentified TDCs in the leachate. Our study indicated the necessity of conducting in vivo bioassays to detect thyroid dysfunctions caused by leachate. PMID:26950620

  9. Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans via fish consumption and dioxin-like activity in fish determined by H4IIE-luc bioassay

    International Nuclear Information System (INIS)

    Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) via fish consumption in two major electronic (e) waste sites: Guiyu (GY), Guangdong Province and Taizhou (TZ), Zhejiang Province, and dioxin-like activity in fish determined by H4IIE-luc bioassay. In the present study, all fish were below EU's maximum allowable concentration in muscle of fish (4 pg WHO-TEQ/g wet wt), except crucian (4.28 pg WHO-TEQ/g wet wt) and silver carps (7.49 pg WHO-TEQ/g wet wt) collected from GY rivers. Moreover, the residual concentration in bighead carp collected from GY (2.15 pg WHO-TEQ/g wet wt) was close to the EU's action level (3 pg WHO-TEQ/g wet wt) which gives “early warning” to the competent authorities and operators to take measures to eliminate contamination. In addition, results indicated that the maximum human intake of PCDD/Fs via freshwater fish consumption in GY was 4.31 pg WHO-TEQ/kg bw/day, which exceeds the higher end of the tolerable daily intake recommended by the WHO, EC-SCF and JECFA (1–4, 2 and 2.3 pg WHO-TEQ/kg bw/day respectively). Furthermore, H4IIE-luc cell bioassay provides a very sensitive and cost-efficient screening tool for assessing the overall dioxin-like toxicity in the study, and is therefore valuable for high-throughput environmental monitoring studies. - Highlights: ► Freshwater fish are contaminated by PCDD/F at 2 e-waste sites in China. ► Guiyu residents are exposed to unsafe levels of PCDD/Fs through dietary exposure. ► H4IIE-luc cell bioassay provides a very sensitive screening tool for PCDD/Fs

  10. Scenario-targeted toxicity assessment through multiple endpoint bioassays in a soil posing unacceptable environmental risk according to regulatory screening values.

    Science.gov (United States)

    Rodriguez-Ruiz, A; Etxebarria, J; Boatti, L; Marigómez, I

    2015-09-01

    Lanestosa is a chronically polluted site (derelict mine) where the soil (Lanestosa (LA) soil) exceeds screening values (SVs) of regulatory policies in force (Basque Country; Europe) for Zn, Pb and Cd. A scenario-targeted toxicity assessment was carried out on the basis of a multi-endpoint bioassay approach. Acute and chronic toxicity bioassays were conducted with selected test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates and with bioaccumulation studies in earthworms. Besides, the toxicity profile was compared with that of the mine runoff (RO) soil and of a fresh artificially polluted soil (LAAPS) resembling LA soil pollutant profile. Extractability studies in LA soil revealed that Pb, Zn and Cd were highly available for exchange and/or release into the environment. Indeed, Pb and Zn were accumulated in earthworms and LA soil resulted to be toxic. Soil respiration, V. fischeri, vegetative and developmental cycles of D. discoideum and survival and juvenile production of E. fetida were severely affected. These results confirmed that LA soil had unacceptable environmental risk and demanded intervention. In contrast, although Pb and Zn concentrations in RO soil revealed also unacceptable risk, both metal extractability and toxicity were much lower than in LA soil. Thus, within the polluted site, the need for intervention varied between areas that posed dissimilar risk. Besides, since LAAPS, with a high exchangeable metal fraction, was the most toxic, ageing under in situ natural conditions seemingly contributed to attenuate LA soil risk. As a whole, combining multi-endpoint bioassays with scenario-targeted analysis (including leaching and ageing) provides reliable risk assessment in soils posing unacceptable environmental risk according to SVs, which is useful to optimise the required intervention measures. PMID:25940475

  11. Analysis of PCDD/Fs and dioxin-like PCBs in atmospheric deposition samples from the Flemish measurement network: Optimization and validation of a new CALUX bioassay method.

    Science.gov (United States)

    Croes, K; Van Langenhove, K; Elskens, M; Desmedt, M; Roekens, E; Kotz, A; Denison, M S; Baeyens, W

    2011-01-01

    Since the CALUX (Chemically Activated LUciferase gene eXpression) bioassay is a fast, sensitive and inexpensive tool for the analysis of a high number of samples, validation of new methods is urgently needed. In this study, a new method for the analysis of PCDD/Fs and dioxin-like PCBs in atmospheric deposition samples with the CALUX bioassay was developed, optimized and validated. The method consists of 4 steps: filtration, extraction, clean up and bioassay analysis. To avoid the use of large amounts of toxic solvents, new techniques were used for filtration and extraction: a C18 filter was used instead of a liquid/liquid extraction and an Accelerated Solvent Extractor (ASE) was used instead of the traditional soxhlet extraction. After pre-oxidation of the sample extract, clean up was done using a multi-layer silica gel column coupled to a carbon column. The PCDD/F and PCB fractions were finally analyzed with the H1L7.5c1 and/or the H1L6.1c3 mouse hepatoma cell lines. The limit of quantification was 1.4pg CALUX-BEQm(-2)d(-1) for the PCBs and 5.6pgCALUX-BEQm(-2)d(-1) for the PCDD/Fs, when using the new sensitive H1L7.5c1 cell line. The GC-HRMS recovery for all PCDD/F congeners was between 55% and 112%, with a mean recovery of 90%. CALUX recoveries of spiked procedural blanks were between the accepted ranges of 80-120%. Repeatability and reproducibility were satisfactory and no interferences from metals were detected. The first results from the Flemish measurement program showed good correlation between CALUX and GC-HRMS. PMID:21094512

  12. PET/CT imaging of c-Myc transgenic mice identifies the genotoxic N-nitroso-diethylamine as carcinogen in a short-term cancer bioassay.

    Directory of Open Access Journals (Sweden)

    Katja Hueper

    Full Text Available BACKGROUND: More than 100,000 chemicals are in use but have not been tested for their safety. To overcome limitations in the cancer bioassay several alternative testing strategies are explored. The inability to monitor non-invasively onset and progression of disease limits, however, the value of current testing strategies. Here, we report the application of in vivo imaging to a c-Myc transgenic mouse model of liver cancer for the development of a short-term cancer bioassay. METHODOLOGY/PRINCIPAL FINDINGS: μCT and ¹⁸F-FDG μPET were used to detect and quantify tumor lesions after treatment with the genotoxic carcinogen NDEA, the tumor promoting agent BHT or the hepatotoxin paracetamol. Tumor growth was investigated between the ages of 4 to 8.5 months and contrast-enhanced μCT imaging detected liver lesions as well as metastatic spread with high sensitivity and accuracy as confirmed by histopathology. Significant differences in the onset of tumor growth, tumor load and glucose metabolism were observed when the NDEA treatment group was compared with any of the other treatment groups. NDEA treatment of c-Myc transgenic mice significantly accelerated tumor growth and caused metastatic spread of HCC in to lung but this treatment also induced primary lung cancer growth. In contrast, BHT and paracetamol did not promote hepatocarcinogenesis. CONCLUSIONS/SIGNIFICANCE: The present study evidences the accuracy of in vivo imaging in defining tumor growth, tumor load, lesion number and metastatic spread. Consequently, the application of in vivo imaging techniques to transgenic animal models may possibly enable short-term cancer bioassays to significantly improve hazard identification and follow-up examinations of different organs by non-invasive methods.

  13. A novel marine algal toxicity bioassay based on sporulation inhibition in the green macroalga Ulva pertusa (Chlorophyta)

    International Nuclear Information System (INIS)

    A 5-day aquatic toxicity test based on sporulation inhibition of the green macroalga Ulva pertusa Kjellman has been developed. Optimal test conditions determined for photon irradiance, salinity and temperature were 60-200 μmol photons m-2 s-1, 25-35%o and 15-20 deg C, respectively. Tests were conducted by exposing U. pertusa thallus disks to a reference toxicant (sodium dodecyl sulfate; SDS), metals (Cd2+, Cu2+, Zn2+, Pb2+) and elutriates of sludge collected from nine different locations. The EC50 values for SDS was 5.35 mg L-1. When four heavy metals were assayed, the NOECs were highest for lead (0.625 mg L-1) and lowest for copper (0.031 mg L-1). The EC50 values showed the following toxicity rankings: Cu2+ (0.061 mg L-1) > Cd2+ (0.326 mg L-1) > Zn2+ (0.738 mg L-1) > Pb2+ (0.877 mg L-1). The bioassay indicated also that the sporulation endpoint could be a sensitive indicator of toxicity effects of elutriates of sludge as reflected from the NOEC values equal to or lower than the lowest concentration employed (6.25%). Sporulation was significantly inhibitied in all elutriates with the greatest and least effects observed in elutriates of sludge from industrial waste (EC50 6.78%) and filtration bed (EC50 15.0%), respectively. The results of the Spearman rank correlation analysis for EC50 data versus the concentrations of toxicants in the sludge presented a significant correlation between toxicity and four heavy metals (Cd2+, Cu2+, Pb2+, Zn2+). Introduction of the concept of toxicity unit (TU) showed that these metals were the main cause of toxicity in elutriates of at least four out of nine sludge samples. Members of the order Ulvales show a wide geographic distribution and have similar reproductive characteristics, thus making it possible to apply the present test method to other algae of this taxa, elsewhere. This novel method will be a useful tool for assessing the aquatic toxicity of a wide range of toxicants, once the respective sensitivities are demonstrated

  14. Assessing the ecological long-term impact of wastewater irrigation on soil and water based on bioassays and chemical analyses.

    Science.gov (United States)

    Richter, Elisabeth; Hecht, Fabian; Schnellbacher, Nadine; Ternes, Thomas A; Wick, Arne; Wode, Florian; Coors, Anja

    2015-11-01

    The reuse of treated wastewater for irrigation and groundwater recharge can counteract water scarcity and reduce pollution of surface waters, but assessing its environmental risk should likewise consider effects associated to the soil. The present study therefore aimed at determining the impact of wastewater irrigation on the habitat quality of water after soil passage and of soil after percolation by applying bioassays and chemical analysis. Lab-scale columns of four different soils encompassing standard European soil and three field soils of varying characteristics and pre-contamination were continuously percolated with treated wastewater to simulate long-term irrigation. Wastewater and its percolates were tested for immobilization of Daphnia magna and growth inhibition of green algae (Pseudokirchneriella subcapitata) and water lentils (Lemna minor). The observed phytotoxicity of the treated wastewater was mostly reduced by soil passage, but in some percolates also increased for green algae. Chemical analysis covering an extensive set of wastewater-born organic pollutants demonstrated that many of them were considerably reduced by soil passage, particularly through peaty soils. Taken together, these results indicated that wastewater-born phytotoxic substances may be removed by soil passage, while existing soil pollutants (e.g. metals) may leach and impair percolate quality. Soils with and without wastewater irrigation were tested for growth of plants (Avena sativa, Brassica napus) and soil bacteria (Arthrobacter globiformis) and reproduction of collembolans (Folsomia candida) and oligochaetes (Enchytraeus crypticus, Eisenia fetida). The habitat quality of the standard and two field soils appeared to be deteriorated by wastewater percolation for at least one organism (enchytraeids, plants or bacteria), while for two pre-contaminated field soils it also was improved (for plants and/or enchytraeids). Wastewater percolation did not seem to raise soil concentrations

  15. Effects of cysteamine on pituitary, MTTW15 tumor, and serum prolactin levels measured by rat lymphoma cell bioassay and radioimmunoassay

    International Nuclear Information System (INIS)

    Cysteamine (CSH), a sulfhydryl compound, reduces both serum and anterior pituitary (AP) PRL measured by RIA. We have used the Nb2 lymphoma cell bioassay (BIO) for PRL to evaluate possible CSH-related changes in PRL levels in sera and tissues of male and MtTW15 mammosomatotropic tumor-bearing female rats. Experimental animals received a single sc injection of CSH (300 mg/kg), and samples were collected 0.5-24 h later. Since CSH and serum from CSH rats were toxic in BIO, samples were dialyzed before assay. All samples were evaluated for PRL and GH by RIA as well. A significant decrease (P less than 0.05) in BIO serum PRL was evident in male rats 0.5 h after CSH; levels remained low for 24 h. Serum PRL by RIA was significantly depressed at 4 h but not at 0.5 h or 24 h. PRL in AP extracts was decreased (60-90%) at all times by BIO and RIA. Significant decreases of BIO- and RIA-detectable PRL were recorded in serum and tissues (AP and tumors) at 4 h in tumor rats. Sequentially bled (0.5-4 h) CSH-treated tumor-bearing rats showed 50% and 80% reductions in serum PRL at 1 and 4 h by both BIO and RIA. CSH had no effect on GH levels in sera and tissues of any animal studied at any time interval. Our results substantiate earlier reports on CSH-induced decreases in RIA-detectable PRL. They show that such changes cannot be attributed to assay effects alone, as significant decreases in circulating and stored PRL (both AP and tumor) were evident by BIO. Results with tissue extracts were the most dramatic. They suggest an action of CSH or a metabolic intermediate with stored PRL which reduces both extractable PRL and hormone release. Such an effect of CSH on PRL extraction has been suggested by others. Whatever the mechanism, it appears to be relatively specific, since GH cells were not affected

  16. Laboratory Bioassay of Iranian Isolates of Entomopathogenic Fungus Metarhizium anisopliae (Metsch. Sorokin (Ascomycota: Hypocreales against two Species of Storage Pest

    Directory of Open Access Journals (Sweden)

    Adel Khashaveh

    2013-03-01

    Full Text Available M-B 12.00 Normal 0 false false false EN-US X-NONE FA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} The susceptibility of adults of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae and Oryzaephilus surinamensis L. (Coleoptera: Silvanidae to three Iranian Isolates of the entomopathogenic fungi Metarhizium anisopliae (Metsch. Sorokin was evaluated through bioassays with direct immersion under laboratory conditions. For each isolates, five aqueous suspensions were prepared in a logarithmic series in Tween 80 (0.05% v/v. Results showed that adult of both species were susceptible to all isolates of M. anisopliae. For all three isolates, mortality percentage of the two species increased with increasing conidial concentration and significant difference was observed between concentrations. The corrected cumulative mortality of adult of O. surinamensis 10 days after immersion ranged from 12.38 to 85.84%, 18.6 to 62.83% and 10.63 to 77.87% for different concentrations of DEMI001, IRAN 715C and IRAN 1018C, respectively. These amounts for T. castaneum varied from 31.07 to 74.78%, 26.02 to 75.61% and 23.33 to 89.99% for different concentrations of DEMI001, IRAN 715C and IRAN 1018C, respectively. The parameters of probit analysis demonstrated non-overlap of 95% confidence limits of LC50 and LC95 and significant difference was observed among three isolates tested against each insect. The lowest and the highest LC50 and LC95 values were observed in the isolates DEMI001 for O. surinamensis (3/1×105 and 1/5×108 and IRAN 715C for T. castaneum (6.2×108 and 6.9×1014, respectively. This

  17. A suitability study of the fission product phantom and the bottle manikin absorption phantom for calibration of in vivo bioassay equipment for the DOELAP accreditation testing program

    International Nuclear Information System (INIS)

    Pacific Northwest laboratory (PNL) conducted an intercomparison study of the Fission Product phantom and the bottle manikin absorption (BOMAB) phantom for the US Department of Energy (DOE) to determine the consistency of calibration response of the two phantoms and their suitability for certification and use under a planned bioassay laboratory accreditation program. The study was initiated to determine calibration factors for both types of phantoms and to evaluate the suitability of their use in DOE Laboratory Accreditation Program (DOELAP) round-robin testing. The BOMAB was found to be more appropriate for the DOELAP testing program. 9 refs., 9 figs., 9 tabs

  18. Synthesis and Characterization of N1-Phenylhydrazine-1,2-bis(carbothioamide) and Its Evaluation for Antimicrobial, Antioxidant, and Brine Shrimp Lethality Bioassay

    OpenAIRE

    G. M. Golzar Hossain; Md. Mainul Abedin; Bachar, Sitesh C

    2012-01-01

    The compound N1-phenylhydrazine-1,2-bis(carbothioamide) was synthesised from phenylisothiocyanate reacting with thiosemicarbazide refluxing the mixture in ethanol. The new compound obtained was characterised by various spectral and elemental analyses. It was subjected to antibacterial, antioxidant and brine shrimp lethality bioassay. The compound showed brine shrimp lethality with LC50 value of 12.79 μg which was comparable to vincristine with LC50 value of 0.33 μg. The compound did not exhib...

  19. Chemical and biological profiles of sediments as indicators of sources of contamination in Hamilton Harbour. Part II: bioassay-directed fractionation using the Ames Salmonella/microsome assay

    Energy Technology Data Exchange (ETDEWEB)

    Marvin, C.H.; McCarry, B.E.; Villella, J.; Allan, L.W.; Bryant, D.W. [McMaster University, Hamilton, ON (Canada). Dept. of Chemistry

    2000-07-01

    Bottom sediment and suspended sediment samples from Hamilton Harbour (western Lake Ontario) and from a major tributary were profiled using a bioassay-directed fractionation approach. Fractions which exhibited mutagenic activity contained PAH with molecular masses of 252, 276 and 278 amu; these fractions contained over 80% of the genotoxicity attributable to PAH. Suspended sediments collected near areas known to contain high levels of coal tar-contamination in the bottom sediments contained higher levels of genotoxic PAH than suspended sediments collected from other areas of the harbour.

  20. Evaluation of Toxic, Cytotoxic, Mutagenic, and Antimutagenic Activities of Natural and Technical Cashew Nut Shell Liquids Using the Allium cepa and Artemia salina Bioassays

    OpenAIRE

    Aracelli de Sousa Leite; Alisson Ferreira Dantas; George Laylson da Silva Oliveira; Gomes Júnior, Antonio L.; Sidney Gonçalo de Lima; Antônia Maria das Graças Lopes Citó; de Freitas, Rivelilson M.; Melo-Cavalcante, Ana Amélia de C.; José Arimateia Dantas Lopes

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems’ root of Allium cepa. Effects of the damage induced by CuS...

  1. Assessment of Cytotoxic Activity of Agave cantula Using Brine Shrimp (Artemia salina) Lethality Bioassay

    OpenAIRE

    M D Dhanaraju; B. Heera; K.V. Gowthami; M.VamsiKrishna; Ramachandran, S.

    2011-01-01

    The essence of the present study is to focus on the cytotoxicity of the aqueous and alcoholic extracts of the Indian medicinal plant Agave cantula belonging to the family Agavaceae. Brine shrimp lethality bioassay method was established for the present study and the cytotoxicity was reported in terms of lethality concentration (LC50). The shrimps were hatched and active shrimps were collected and used for the assay, 10 active shrimps were added to the 0.5 mL diluted test solution and the surv...

  2. Plant bioassays to assess toxicity of textile sludge compost Bioensaios vegetais na avaliação da toxidade do composto de lodo têxtil

    Directory of Open Access Journals (Sweden)

    Ademir Sérgio Ferreira Araújo

    2005-06-01

    Full Text Available Composting of industrial wastes is increasing because of recycling requirements set on organic wastes. The evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. The toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. Compost samples were mixed with water (seed germination bioassay or nutrient solution (plant growth bioassay at concentrations of 0, 19, 38, 76 and 152 g L-1. No negative effects were observed after five days of compost water-extract in relation to soybean and wheat seed germination. After fifteen days, under a hydroponics system, plant growth had harmful effects of the compost at concentrations above 38 g L-1. Textile sludge compost presented great phytotoxicity under hydroponics condition and the soybean and wheat were sensitive for evaluation of organic wastes in plant growth bioassays.A compostagem de resíduos industriais tem aumentado devido à pressão para reciclar os resíduos orgânicos. A avaliação da toxicidade destes resíduos por testes biológicos é extremamente importante para selecionar resíduos apropriados para aplicação no solo. A toxicidade do composto de lodo têxtil foi investigada utilizando bioensaios de germinação de sementes e crescimento vegetal em soja e trigo. Amostra do composto foi misturada com água (bioensaio de germinação de sementes ou solução nutritiva (bioensaio de crescimento de plantas em concentrações de 0, 19, 38, 76 e 152 g L-1. Não foram observados efeitos negativos, após cinco dias, do extrato aquoso do composto para a germinação de sementes da soja e do trigo. Após quinze dias em sistema hidropônico, houve efeitos deletérios do composto em concentrações acima de 38 g L-1. O composto de lodo têxtil mostrou maior fitotoxicidade em condições hidropônicas e a soja e o trigo são esp

  3. Lung Carcinogenic Bioassay of CuO and TiO2 Nanoparticles with Intratracheal Instillation Using F344 Male Rats

    OpenAIRE

    YOKOHIRA, MASANAO; Hashimoto, Nozomi; YAMAKAWA, KEIKO; Suzuki, Satoshi; Saoo, Kousuke; KUNO, TOSHIYA; Imaida, Katsumi

    2009-01-01

    Toxicity assessment of nanoparticles, now widespread in our environment, is an important issue. We have focused attention on the carcinogenic potential of copper oxide (CuO) and titanium dioxide (TiO2). In experiment 1, a sequential pilot study, the effectiveness of a carcinogenic bioassay featuring intraperitoneal injection (i.p.) of 20 mg 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) or 0.1% N-bis(2-hydroxypropyl)nitrosamine (DHPN) in drinking water for 2 weeks was examined. Based on...

  4. An entomopathogenic strain of Beauveria bassiana against Frankliniella occidentalis with no detrimental effect on the predatory mite Neoseiulus barkeri: evidence from laboratory bioassay and scanning electron microscopic observation.

    Directory of Open Access Journals (Sweden)

    Shengyong Wu

    Full Text Available Among 28 isolates of Beauveria bassiana tested for virulence against F. occidentalis in laboratory bioassays, we found strain SZ-26 as the most potent, causing 96% mortality in adults at 1×10(7 mL(-1conidia after 4 days. The effect of the strain SZ-26 on survival, longevity and fecundity of the predatory mite Neoseiulus (Amblyseius barkeri Hughes were studied under laboratory conditions. The bioassay results showed that the corrected mortalities were less than 4 and 8% at 10 days following inoculation of the adult and the larvae of the predator, respectively, with 1×10(7 conidia mL(-1 of SZ-26. Furthermore, no fungal hyphae were found in dead predators. The oviposition and postoviposition durations, longevity, and fecundity displayed no significant differences after inoculation with SZ-26 using first-instar larvae of F. occidentalis as prey in comparison with untreated predator. In contrast, the preoviposition durations were significantly longer. Observations with a scanning electron microscope, revealed that many conidia were attached to the cuticles of F. occidentalis at 2 h after treatment with germ tubes oriented toward cuticle at 24 h, penetration of the insect cuticle at 36 h, and finally, fungal colonization of the whole insect body at 60 h. In contrast, we never observed penetration of the predator's cuticle and conidia were shed gradually from the body, further demonstrating that B. bassiana strain SZ-26 show high toxicity against F. occidentalis but no pathogenicity to predatory mite.

  5. Toxicity study of the oil dispersant Corexit 9527 on Macrobrachium rosenbergii (de Man) egg hatchability by using a flow-through bioassay technique.

    Science.gov (United States)

    Law, A T

    1995-01-01

    The effect of the oil-spill dispersant Corexit 9527 on egg-hatching rate of Macrobrachium rosenbergii (de Man) was studied by using an innovated flow-through bioassay technique. This bioassay method relies on the fact that M. rosenbergii fertilized eggs when detached from the mother prawn were able to hatch artificially. The flow-through system generated a stable and good water quality environment for hatching the eggs successfully. The Corexit 9527 had a pronounced effect on hatching rate of the M. rosenbergii eggs. In the control, the hatching rate of the eggs was 95.55% +/- 1.74%. However, it was reduced drastically with increasing concentrations of Corexit 9527. A 100% inhibition of egg hatchability was found when the level of Corexit 9527 was higher than 250 mg litre(-1). The EC(50) and the EC(95) values estimated by the probit method were 80.4 +/- 5.5 mg litre(-1) and 193.5 +/- 39.9 mg litre(-1) respectively (P = 0.05). The recommended safety level of Corexit 9527 for M. rosenbergii in Malaysian estuarine waters is below 40 mg litre(-1). PMID:15091547

  6. 3,3',5-Triiodo-L-thyronine-like activity in effluents from domestic sewage treatment plants detected by in vitro and in vivo bioassays

    International Nuclear Information System (INIS)

    Thyroid system-disrupting activity in effluents from municipal domestic sewage treatment plants was detected using three in vitro assays and one in vivo assay. Contaminants in the effluents were extracted by solid-phase extraction (SPE) and eluted stepwise with different organic solvents. The majority of the thyroid system-disrupting activity was detected in the dichloromethane/methanol (1/1) fraction after SPE in all three in vitro assays: competitive assays of 3,3',5-[125I]triiodo-L-thyronine ([125I]T3) binding to the plasma protein transthyretin (TTR assay) and thyroid hormone receptor (TR assay) and T3-dependent luciferase assay (Luc assay). Subsequent reverse-phase high-performance liquid chromatography (RP-HPLC) of the dichloromethane/methanol (1/1) fraction separated contaminants potent in the TR and Luc assays from those potent in the TTR assay. The contaminants potent in the TR and Luc assays were also potent in an in vivo short-term gene expression assay in Xenopus laevis (Tadpole assay). The present study demonstrated that the effluents from domestic sewage treatment plants contain contaminants with T3-like activity of ∼ 10-10 M T3-equivalent concentration (T3EQ) and that the TR and Luc assays are powerful in vitro bioassays for detecting thyroid system-disrupting activity in effluents. The availability and applicability of these bioassays for screening contaminants with thyroid system-disrupting activity in the water environment are discussed

  7. Light-Addressed Electrodeposition of Enzyme-Entrapped Chitosan Membranes for Multiplexed Enzyme-Based Bioassays Using a Digital Micromirror Device

    Directory of Open Access Journals (Sweden)

    Yeu-Long Jiang

    2013-08-01

    Full Text Available This paper describes a light-addressed electrolytic system used to perform an electrodeposition of enzyme-entrapped chitosan membranes for multiplexed enzyme-based bioassays using a digital micromirror device (DMD. In this system, a patterned light illumination is projected onto a photoconductive substrate serving as a photo-cathode to electrolytically produce hydroxide ions, which leads to an increased pH gradient. The high pH generated at the cathode can cause a local gelation of chitosan through sol-gel transition. By controlling the illumination pattern on the DMD, a light-addressed electrodeposition of chitosan membranes with different shapes and sizes, as well as multiplexed micropatterning, was performed. The effect of the illumination time of the light pattern on the dimensional resolution of chitosan membrane formation was examined experimentally. Moreover, multiplexed enzyme-based bioassay of enzyme-entrapped chitosan membranes was also successfully demonstrated through the electrodeposition of the chitosan membranes with various shapes/sizes and entrapping different enzymes. As a model experiment, glucose and ethanol were simultaneously detected in a single detection chamber without cross-talk using shape-coded chitosan membranes entrapped with glucose oxidase (GOX, peroxidase (POD, and Amplex Red (AmR or alcohol oxidase (AOX, POD, and AmR by using same fluorescence indicator (AmR.

  8. The use of a brine shrimp (Artemia salina) bioassay to assess the water quality in Hangzhou section of Beijing-Hangzhou Grand Canal.

    Science.gov (United States)

    Lu, Yin; Xu, Xiaolu; Li, Tian; Xu, Yifei; Wu, Xu

    2012-03-01

    As physical and chemical tests alone are not sufficient enough for the assessment of potential effects on aquatic organisms, bioassays are required for the integrated evaluation of water pollution. In this study, invertebrate crustacean Artemia salina (brine shrimp) was applied as an indicator to assess the water quality of Hangzhou Section of Beijing-Hangzhou Grand Canal. The percentage mortality of brine shrimp was recorded after 24-h exposure to the Canal water. The water samples were collected from five typical sites during October 2008 and April 2009. It exhibited 11% ± 8.3%, 26.7% ± 17%, 31.7% ± 8.5%, 28.0% ± 11.7%, and 4% ± 4.3% percentage mortality for the sample from Tangxi Bridge, Yi Bridge, Gongchen Bridge, Maiyu Bridge, and Gujia Bridge in 2008, respectively. And it exhibited 5.7% ± 4.2%, 10.3% ± 8.2%, 24.3% ± 12.3%, 16.0% ± 12.3%, and 0%, percentage mortality in 2009, respectively. According to the results, a relative improvement in water quality was observed, although the results were not significantly different at the p water toxicity when alternative bioassays were unavailable. PMID:22187021

  9. Analysis of Bioactive Components of Oilseed Cakes by High-Performance Thin-Layer Chromatography-(Bioassay Combined with Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Sue-Siang Teh

    2015-03-01

    Full Text Available Hemp, flax and canola seed cakes are byproducts of the plant oil extraction industry that have not received much attention in terms of their potential use for human food instead of animal feed. Thus, the bioactivity profiling of these oilseed cakes is of interest. For their effect-directed analysis, planar chromatography was combined with several (bioassays, namely 2,2-diphenyl-1-picrylhydrazyl scavenging, acetylcholine esterase inhibition, planar yeast estrogen screen, antimicrobial Bacillus subtilis and Aliivibrio fischeri assays. The streamlined high-performance thin-layer chromatography (HPTLC-bioassay method allowed the discovery of previously unknown bioactive compounds present in these oilseed cake extracts. In contrast to target analysis, the direct link to the effective compounds allowed comprehensive information with regard to selected effects. HPTLC-electrospray ionization-mass spectrometry via the elution-head based TLC-MS Interface was used for a first characterization of the unknown effective compounds. The demonstrated bioactivity profiling on the feed/food intake side may guide the isolation of active compounds for production of functional food or for justified motivation of functional feed/food supplements.

  10. Genotoxicity of Water Contaminants from the Basin of Lake Sevan, Armenia Evaluated by the Comet Assay in Gibel Carp (Carassius auratus gibelio) and Tradescantia Bioassays.

    Science.gov (United States)

    Simonyan, Anna; Gabrielyan, Barduch; Minasyan, Seyran; Hovhannisyan, Galina; Aroutiounian, Rouben

    2016-03-01

    Combination of bioassays and chemical analysis was applied to determine the genotoxic/mutagenic contamination in four different sites of the basin of Lake Sevan in Armenia. Water genotoxicity was evaluated using the single cell gel electrophoresis technique (comet assay) in erythrocytes of gibel carp (Carassius auratus gibelio), Tradescantia micronucleus (Trad-MCN) and Tradescantia stamen hair mutation (Trad-SHM) assays. Significant inter-site differences in the levels of water genotoxicity according to fish and Trad-MCN bioassays have been revealed. Two groups of locations with lower (south-southwest of the village Shorzha and Peninsula of Lake Sevan) and higher (estuaries of Gavaraget and Dzknaget rivers) levels of water genotoxicity were distinguished. Correlation analysis support the hypothesis that the observed genetic alterations in fish and plant may be a manifestation of the effects of water contamination by nitrate ions, Si, Al, Fe, Mn and Cu. Increase of DNA damage in fish also correlated with content of total phosphorus. PMID:26739952

  11. Development of an edema factor-mediated cAMP-induction bioassay for detecting antibody-mediated neutralization of anthrax protective antigen.

    Science.gov (United States)

    Zmuda, Jonathan F; Zhang, Linyi; Richards, Terri; Pham, Quyen; Zukauskas, David; Pierre, Jennifer L; Laird, Michael W; Askins, Janine; Choi, Gil H

    2005-03-01

    Intoxication of mammalian cells by Bacillus anthracis requires the coordinate activity of three distinct bacterial proteins: protective antigen (PA), edema factor (EF), and lethal factor (LF). Among these proteins, PA has become the major focus of work on monoclonal antibodies and vaccines designed to treat or prevent anthrax infection since neither EF nor LF is capable of inducing cellular toxicity in its absence. Here, we present the development of a sensitive, precise, and biologically relevant bioassay platform capable of quantifying antibody-mediated PA neutralization. This bioassay is based on the ability of PA to bind and shuttle EF, a bacterial adenylate cyclase, into mammalian cells leading to an increase in cAMP that can be quantified using a sensitive chemiluminescent ELISA. The results of this study indicate that the cAMP-induction assay possesses the necessary performance characteristics for use as both a potency-indicating release assay in a quality control setting and as a surrogate pharmacodynamic marker for ensuring the continued bioactivity of therapeutic antibodies against PA during clinical trials. PMID:15847796

  12. Unusual non-fluorescent broad spectrum siderophore activity (SID EGYII) by Pseudomonas aeruginosa strain EGYII DSM 101801 and a new insight towards simple siderophore bioassay.

    Science.gov (United States)

    Embaby, Amira M; Heshmat, Yasmin; Hussein, Ahmed

    2016-03-01

    Present study highlights an unusual non-fluorescent hydroxamate broad spectrum siderophore (SID EGYII) activity from Pseudomonas aeruginosa strain EGYII DSM 101801, a soil bacterial isolate, along with simple low cost effective siderophore bioassay. Detection of SID EGYII activity qualitatively was proved by masking this activity against Erwinia amylovora strain EGY1 DSM 101800, an indicator strain, in well-cut diffusion assay containing 100 µM FeCl3. SID EGYII activity was expressed quantitatively as arbitrary units [Siderophore arbitrary units (SAU)] 380 SAU/mL against E. amylovora strain EGY1 DSM 101800. Maximal SID EGYII activity was achieved upon growing P. aeruginosa strain EGYII DSM 101801 in PYB broth at 180 rpm for 24 h. SID EGYII displayed a broad spectrum antimicrobial activity against some human pathogens (i.e., Gram-positive bacteria, Gram-negative bacteria and yeasts) and a fireblight plant pathogen. Interestingly, transformants of Escherichia coli JM109 (DE3)pSID/EGYII harboring P. aeruginosa strain EGYII DSM 101801 plasmid demonstrated a perceivable antimicrobial activity against E. amylovora strain EGY1 DSM 101800. The broad spectrum antimicrobial activity of the unusual non-fluorescent SID EGYII would underpin its high potential in targeting bacterial pathogens posing probable threats to human health and agricultural economy. The present simple low cost effective bioassay is a new insight towards an alternative to the expensive cumbersome siderophore Chrome Azurol S assay. PMID:27015845

  13. Bioassay-Guided Chemical Study of the Anti-Inflammatory Effect of Senna villosa (Miller H.S. Irwin & Barneby (Leguminosae in TPA-Induced Ear Edema

    Directory of Open Access Journals (Sweden)

    Ana del Carmen Susunaga-Notario

    2014-07-01

    Full Text Available Senna villosa (Miller is a plant that grows in México. In traditional Mexican medicine, it is used topically to treat skin infections, pustules and eruptions and to heal wounds by scar formation. However, studies of its potential anti-inflammatory effects have not been performed. The aim of the present study was to determine the anti-inflammatory effect of extracts from the leaves of Senna villosa and to perform a bioassay-guided chemical study of the extract with major activity in a model of ear edema induced by 12-O-tetradecanoylphorbol 13-acetate (TPA. The results reveal that the chloroform extract from Senna villosa leaves has anti-inflammatory and anti-proliferative properties. Nine fractions were obtained from the bioassay-guided chemical study, including a white precipitate from fractions 2 and 3. Although none of the nine fractions presented anti-inflammatory activity, the white precipitate exhibited pharmacological activity. It was chemically characterized using mass spectrometry and infrared and nuclear magnetic resonance spectroscopy, resulting in a mixture of three aliphatic esters, which were identified as the principal constituents: hexyl tetradecanoate (C20H40O2, heptyl tetradecanoate (C21H42O2 and octyl tetradecanoate (C22H44O2. This research provides, for the first time, evidence of the anti-inflammatory and anti-proliferative properties of compounds isolated from Senna villosa.

  14. Novel bioassay for the discovery of inhibitors of the 2-C-methyl-D-erythritol 4-phosphate (MEP and terpenoid pathways leading to carotenoid biosynthesis.

    Directory of Open Access Journals (Sweden)

    Natália Corniani

    Full Text Available The 2-C-methyl-D-erythritol 4-phosphate (MEP pathway leads to the synthesis of isopentenyl diphosphate in plastids. It is a major branch point providing precursors for the synthesis of carotenoids, tocopherols, plastoquinone and the phytyl chain of chlorophylls, as well as the hormones abscisic acid and gibberellins. Consequently, disruption of this pathway is harmful to plants. We developed an in vivo bioassay that can measure the carbon flow through the carotenoid pathway. Leaf cuttings are incubated in the presence of a phytoene desaturase inhibitor to induce phytoene accumulation. Any compound reducing the level of phytoene accumulation is likely to interfere with either one of the steps in the MEP pathway or the synthesis of geranylgeranyl diphosphate. This concept was tested with known inhibitors of steps of the MEP pathway. The specificity of this in vivo bioassay was also verified by testing representative herbicides known to target processes outside of the MEP and carotenoid pathways. This assay enables the rapid screen of new inhibitors of enzymes preceding the synthesis of phytoene, though there are some limitations related to the non-specific effect of some inhibitors on this assay.

  15. Synthesis and Characterization of N1-Phenylhydrazine-1,2-bis(carbothioamide and Its Evaluation for Antimicrobial, Antioxidant, and Brine Shrimp Lethality Bioassay

    Directory of Open Access Journals (Sweden)

    G. M. Golzar Hossain

    2012-01-01

    Full Text Available The compound N1-phenylhydrazine-1,2-bis(carbothioamide was synthesised from phenylisothiocyanate reacting with thiosemicarbazide refluxing the mixture in ethanol. The new compound obtained was characterised by various spectral and elemental analyses. It was subjected to antibacterial, antioxidant and brine shrimp lethality bioassay. The compound showed brine shrimp lethality with LC50 value of 12.79 μg which was comparable to vincristine with LC50 value of 0.33 μg. The compound did not exhibit any antimicrobial activity against Gram +ve and Gram −ve organisms, as well as against the tested fungal strains. But very good free radical scavenging activity was observed at concentration range of 0.185–100 μg with IC50 values of 1.43 μg in comparison to reference standard butylated hydroxytoluene (BHT with IC50 value 16.46 μg.

  16. Probabilistic risk assessment of diuron and prometryn in the Gwydir River catchment, Australia, with the input of a novel bioassay based on algal growth.

    Science.gov (United States)

    Shi, Yajuan; Burns, Mitchell; Ritchie, Raymond J; Crossan, Angus; Kennedy, Ivan R

    2014-08-01

    A probabilistic risk assessment of the selected herbicides (diuron and prometryn) in the Gwydir River catchment was conducted, with the input of the EC₅₀ values derived from both literature and a novel bioassay. Laboratory test based on growth of algae exposed to herbicides assayed with a microplate reader was used to examine the toxicity of diuron and prometryn on the growth of Chlorella vulgaris. Both herbicides showed concentration dependent toxicity in inhibiting the growth of Chlorella during the exposure period of 18-72 h. Diuron caused more toxicity as judged by growth rates than prometryn. Thalaba Creek at Merrywinebone was identified as the 'hotspot' for diuron and prometryn risk in the Gwydir catchment. The use of microplate assays coupled with probabilistic risk assessment is recommended for rapid assessment of ecotoxicity of indigenous species, allowing identification of locations in river catchments requiring environmental management. PMID:24859706

  17. Identification of Lilial as a fragrance sensitizer in a perfume by bioassay-guided chemical fractionation and structure-activity relationships

    DEFF Research Database (Denmark)

    Arnau, E G; Andersen, Klaus Ejner; Bruze, M;

    2000-01-01

    Fragrance materials are among the most common causes of allergic contact dermatitis. The aim of this study was to identify in a perfume fragrance allergens not included in the fragrance mix, by use of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships...... (SARs). The basis for the investigation was a 45-year-old woman allergic to her own perfume. She had a negative patch test to the fragrance mix and agreed to participate in the study. Chemical fractionation of the perfume concentrate was used for repeated patch testing and/or repeated open application...... chemical structure, indicating an ability to modify skin proteins and thus behave as a skin sensitizer, were tested on the patient. The patient reacted positively to the synthetic fragrance p-t-butyl-alpha-methylhydrocinnamic aldehyde (Lilial), a widely used fragrance compound not present in the fragrance...

  18. Results of bulk sediment analysis and bioassay testing on selected sediments from Oakland Inner Harbor and Alcatraz disposal site, San Francisco, California

    Energy Technology Data Exchange (ETDEWEB)

    Word, J Q; Ward, J A; Woodruff, D L

    1990-09-01

    The Battelle/Marine Sciences Laboratory (MSL) was contracted by the US Army Corps of Engineers, San Francisco District, to perform bulk sediment analysis and oyster larvae bioassays (elutriate) on sediments from Inner Oakland Harbor, California. Analysis of sediment characteristics by MSL indicated elevated priority pollutants, PAHs, pesticides, metals, organotins, and oil and grease concentrations, when compared to Alcatraz Island Dredged Material Disposal Site sediment concentrations. Larvae of the Pacific oyster, Crassostrea gigas, were exposed to seawater collected from the Alcatraz Island Site water, and a series of controls using water and sediments collected from Sequim Bay, Washington. Exposure of larvae to the Alcatraz seawater and the 50% and 100% elutriate concentrations from each Oakland sediment resulted in low survival and a high proportion of abnormal larvae compared to Sequim Bay control exposures. MSL identified that field sample collection, preservation, and storage protocols used by Port of Oakland contractors were inconsistent with standard accepted practices. 23 refs., 10 figs., 40 tabs.

  19. A sensitive crude oil bioassay indicates that oil spills potentially induce a change of major nitrifying prokaryotes from the Archaea to the Bacteria

    International Nuclear Information System (INIS)

    The sensitivity of nitrifiers to crude oil released by the BP Deepwater Horizon oil spill in Gulf of Mexico was examined using characterized ammonia-oxidizing bacteria and archaea to develop a bioassay and to gain further insight into the ecological response of these two groups of microorganisms to marine oil spills. Inhibition of nitrite production was observed among all the tested ammonia-oxidizing organisms at 100 ppb crude oil. Nitrosopumilus maritimus, a cultured representative of the abundant Marine Group I Archaea, showed 20% inhibition at 1 ppb, a much greater degree of sensitivity to petroleum than the tested ammonia-oxidizing and heterotrophic bacteria. The differing susceptibility may have ecological significance since a shift to bacterial dominance in response to an oil spill could potentially persist and alter trophic interactions influenced by availability of different nitrogen species. - Oil spills potentially induce a change of major nitrifying prokaryotes from the archaea to the bacteria.

  20. Results of bulk sediment analysis and bioassay testing on selected sediments from Oakland Inner Harbor and Alcatraz disposal site, San Francisco, California

    International Nuclear Information System (INIS)

    The Battelle/Marine Sciences Laboratory (MSL) was contracted by the US Army Corps of Engineers, San Francisco District, to perform bulk sediment analysis and oyster larvae bioassays (elutriate) on sediments from Inner Oakland Harbor, California. Analysis of sediment characteristics by MSL indicated elevated priority pollutants, PAHs, pesticides, metals, organotins, and oil and grease concentrations, when compared to Alcatraz Island Dredged Material Disposal Site sediment concentrations. Larvae of the Pacific oyster, Crassostrea gigas, were exposed to seawater collected from the Alcatraz Island Site water, and a series of controls using water and sediments collected from Sequim Bay, Washington. Exposure of larvae to the Alcatraz seawater and the 50% and 100% elutriate concentrations from each Oakland sediment resulted in low survival and a high proportion of abnormal larvae compared to Sequim Bay control exposures. MSL identified that field sample collection, preservation, and storage protocols used by Port of Oakland contractors were inconsistent with standard accepted practices. 23 refs., 10 figs., 40 tabs

  1. Development, validation and routine application of the in vitro REA and DR-CALUX reporter gene bioassays for the screening of estrogenic compounds and dioxins in food and feed

    NARCIS (Netherlands)

    Bovee, T.F.H.

    2006-01-01

    A dedicated cell-line was developed by the Department of Toxicology of Wageningen University in a joined project with the University of California in Davis and the RIKILT-WUR - Institute of Food Safety in Wageningen. This DR-CALUX ® bioassay was tested, optimised and validated for its use

  2. Estudo fitoquímico de Unonopsis lindmanii - Annonaceae, biomonitorado pelo ensaio de toxicidade sobre a Artemia salina leach Activity - guided isolation of constituents of Unonopsis lindmanii - Annonaceae, based on the brine shrimp lethality bioassay

    OpenAIRE

    João Máximo de Siqueira; Mauro Dionei Bomm; Núbia Fernanda Gomes Pereira; Walmir Silva Garcez; Maria Amélia Diamantino Boaventura

    1998-01-01

    Extracts obtained from leaves, seeds and bark of Unonopsis lindmanii were evaluated by means of Brine Shrimp Lethality test (BSL). Through bioassay-guided chromatographic fractionation, liriodenine, an oxoaporphine alkaloid, was isolated from the bark extracts as the bioactive compound. Two additional inactive known alkaloids, unonopsine and lysicamine were also isolated from the bark extracts.

  3. 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.

    Science.gov (United States)

    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

  4. 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

    Directory of Open Access Journals (Sweden)

    Young-Joon Ahn

    2013-05-01

    Full Text Available 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.

  5. Transfer modelling and toxicity evaluation of the effluent from an installation of cleansing and uranium recovery using a battery of bioassays.

    Science.gov (United States)

    Gagnaire, Béatrice; Boyer, Patrick; Bonzom, Jean-Marc; Lecomte-Pradines, Catherine; Simon, Olivier; Gilbin, Rodolphe

    2011-01-01

    On July 7, 2008, a leak of effluent from an Installation of Cleansing and Uranium Recovery (Tricastin, France) led to the spillage of uranium in a stream. The acute toxicity of the effluent was evaluated, and compared to the toxicity of uranium nitrate in bioassays using several organisms: Chlamydomonas reinhardtii, Daphnia magna, Chironomus riparius and Danio rerio. A sediment bioassay was also performed on C. riparius using water and sediment sampled along the river. Results showed that effluent EC(50) 72 h was 0.65 mg U/l for algae and LC(50) 48 h was 1.67 mg U/l for daphnia, while values obtained for uranium nitrate were higher. The LC(50) 96 h of effluent to C. riparius was 22.7 mg U/l, similar to value for uranium nitrate; the sediment collected was not toxic to C. riparius larvae. The LOEC of effluent and uranium nitrate on HT(50) of D. rerio were similar (0.03 mg U/l), but larvae were more sensitive to uranium nitrate than to effluent. Our results suggest that other substances contained in the effluent could potentially be toxic to wildlife in association with uranium. In parallel, the modelling of the transfers based on uranium measurements in the surface water was used to fill data gaps and assess the impact along the river. These results provided an estimate of exposure conditions that occurred along the river. This approach allowed us to see that the risk to ecosystem during this incident was certainly low and concerned a short period of time, but it could have existed at least for some species. PMID:21107686

  6. Using the dioxin receptor-CALUX in vitro bioassay to screen marine harbor sediments for compounds with a dioxin-like mode of action.

    Science.gov (United States)

    Stronkhorst, Joost; Leonards, Pim; Murk, Albertinka J

    2002-12-01

    The presence of dioxin-like compounds in sediments from harbors and reference sites along the Dutch coast was investigated using the dioxin receptor-chemically activated luciferase gene expression (DR-CALUX) bioassay. The DR-CALUX response varied between 0.2 and 136 ng/kg dry weight expressed in units of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalency quotients (TEQ). The highest CALUX-TEQ values (> 50 ng TEQ/kg dry wt) were found in sediments from the center of the Port of Rotterdam and from the North Sea canal near Amsterdam. The DR-CALUX activity of harbor sediments was classified by setting guideline values. None of the 257 harbor sediment samples investigated exceeded the maximum value of 1,000 ng TEQ/ kg, while 94% of the samples fail the target value of 2 ng TEQ/kg. Threshold values (25 and 50 ng TEQ/kg) are intended as pass/ fail criteria for offshore disposal of dredged material and were exceeded in 12 and 3% of the samples, respectively. DR-CALUX response did not always match with contamination of polychlorinated biphenyls (PCBs) as determined in bulk sediments (sigma7-PCB ranging from < 1 to 456 microg/kg dry wt). Concentrations of planar PCBs, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated-dibenzofuranes (PCDFs), polybrominated biphenyls (PBBs), and polybrominated-diphenylethers (PBDEs) were determined in 20 selected sediment extracts. On average, PCDD/Fs explained 50% of the DR-CALUX activity and planar PCBs 6%. Further research is needed to elucidate the unexplained part of the DR-CALUX response. The DR-CALUX is a highly sensitive and reproducible bioassay that can usefully complement standard PCB analysis, improving the hazard assessment of the disposal of dredged material in the North Sea. PMID:12463548

  7. Acute toxicity over Ceriodaphnia silvestrii and Daphnia magna: Bioassays with water samples from a dam under the influence of uranium mine and with manganese

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Carla R.; Nascimento, Heliana de Azevedo Franco do; Silverio, Emilia Gabriela Costa; Bruschi, Armando Luis; Roque, Claudio Vitor; Nascimento, Marcos Roberto L.; Bonifacio, Rodrigo Leandro, E-mail: carlarolimferrari@yahoo.com.br, E-mail: hazevedo@cnen.gov.br, E-mail: emiliagcsilverio@hotmail.com, E-mail: abruschi@cnen.gov.br, E-mail: cvroque@cnen.gov.br, E-mail: pmarcos@cnen.gov.br, E-mail: rodrigo@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Rodgher, Suzelei [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sao Jose dos Campos, SP (Brazil). Dep. de Engenharia Ambiental

    2015-07-01

    Treated effluents from uranium mine with acid mine drainage can impact receiving water bodies. AMD is relevant from the environmental view due to the large volume of effluents generated, known to affect aquatic biota. Studies show that one of the main problems of treated effluents released by UTM/INB on the catchment basin of Ribeirao das Antas is associated to high Mn values in water samples. In this context, acute 48-h toxicity tests with Mn were conducted with Ceriodaphnia silvestrii and Daphnia magna to determine the No Observed Effect Concentration (NOEC) and the Observed Effect Concentration (OEC) in laboratory bioassays and to verify the potential toxicity of the Mn in face of concentrations found in water samples from the Antas Dam, which receives treated effluents from UTM/INB. In this study, preliminary results of acute toxicity for C. silvestrii indicated OEC values between 9.0 and 10.0 mg Mn/L and NOEC < 3.0 mg Mn/L. For D. magna, OEC and NOEC concentrations were ≥ 30 mg Mn/L and ≤ 80 mg Mn/L, respectively. It was verified that Mn concentrations determined in environmental samples registered the highest value at 1.75 mg Mn/L, below the OEC concentrations recorded for both species. Since manganese occurs in the composition of the effluent that may contain other stable and radioactive elements, complementary ecotoxicological tests must be conducted, aiming at the assessment of synergistic and antagonistic effects of the chemical mixture that makes up the radioactive effluents that are treated and released at the Antas Dam. Such bioassays are underway in the Radioecology Laboratory at LAPOC/CNEN. (author)

  8. Bioassay-guided isolation, identification and molecular ligand-target insight of lipoxygenase inhibitors from leaves of Anisomeles malabarica R.Br.

    Directory of Open Access Journals (Sweden)

    A Sudha

    2014-01-01

    Full Text Available Background: Anisomeles malabarica R. Br. (Lamiaceae is extensively used in traditional medicine in major parts of India for several medicinal purposes, including their use in rheumatism. Materials and Methods: The air-dried leaves of A. malabarica were extracted with ethanol, defatted with n-hexane and then successively partitioned into chloroform and n-butanol fractions. Bioassay-guided fractionation and purification of chloroform fraction from A. malabarica lead to the isolation of lipoxygenase (LOX inhibitors. The structures of isolated compounds were elucidated by ultraviolet, infrared, 1 H nuclear magnetic resonance (NMR, 13 C NMR and mass spectrometry spectroscopic techniques and assessed further by in vitro soybean lipoxygenase (sLOX assay. In addition, the enzyme type inhibition was evaluated through molecular docking technique as a part of computational study. Results: The bioactive compounds 3, 4 dihydroxy benzoic acid (1 and 4′, 5, 7-trihydroxyflavone (2 were isolated from chloroform fraction of A. malabarica, whose bioactivity was observed to be dose-dependent compared to n-butanol fraction. Among the compounds, 3, 4 dihydroxy benzoic acid showed significant sLOX inhibitory activity with 74.04% ±2.6% followed by 4′, 5, 7-trihydroxyflavone (34.68% ±1.9%. The computational analysis of compounds showed their molecular interaction with important amino acid residues and nonheme iron atom in the catalytic site of LOX by enlightening their potential binding mode at molecular level. Conclusions: The LOX inhibitory constituents were identified from A. malabarica by means of bioassay-guided fractionation process. The results derived from in vitro and computational experiments confirm the potential of the isolated compounds and provide additional evidence for its traditional use in inflammatory disorders.

  9. Bioassay of Estrogenic Activity of Effluent and Influent in a Farm Wastewater Treatment Plant Using an in vitro Recombinant Assay with Yeast Cells

    Institute of Scientific and Technical Information of China (English)

    XIANG-MING LI; FANG-NI LUO; GuI-XIA LIU; PING-TING ZHU

    2008-01-01

    Objective Environmental estrogens at an elevated concentration are known to produce adverse effects on human and animal life. However, the majority of researches have been focused on ndustrial discharges, while the impact of livestock wastes as a source of endocrine disrupters in aquatic environments has been rarely elucidated. In order to investigate the contribution of environmental estrogens from livestock, the estrogenic activity in water samples from a farm wastewater treatment plant was analyzed by a recombinant yeast screening method. Methods The extracts prepared from 15 selected water samples from the farm wastewater treatment plant, among which 6 samples were from pre-treatment section (influents) and 9 from post-treatment section (effluents), were analyzed for estrogenic activity by cellar bioassay. Yeast cells transfected with the expression plasmid of human estrogen receptor and the Lac Z reporter plasmid encoding β-galactossidase, were used to measure the estrogen-like compounds in the farm wastewater treatment plant. Results The wastewater samples from influents showed a higher estrogenic potency than the effluent samples showing a low induction of β-galactossidase relative to solvent control condition. By comparison with a standard curve for 1713-estradiol (E2), estrogenic potency in water samples from the influents was calculated as E2-equivalent and ranged from 0.1 to 150 pM E2-equivalent. The estrogenic potency in water samples from the effluents was significantly lower than that in the influents, and 7 water samples had less detectable limit in the total of 9 samples. Conclusion Yeast bioassay of estrogenic activity in most of the samples from the farm wastewater after disposal by traditional sewage treatment showed negative results.

  10. A new in vitro screening bioassay for the ecotoxicological evaluation of the estrogenic responses of environmental chemicals using roach (Rutilus rutilus) liver explant culture.

    Science.gov (United States)

    Gerbron, Marie; Geraudie, Perrine; Rotchell, Jeanette; Minier, Christophe

    2010-10-01

    There is growing evidence that many chemicals released in the environment are able to disturb the normal endocrinology of organisms affecting the structure and function of their reproductive system. This has prompted the scientific community to develop appropriate testing methods to identify active compounds and elucidate mechanisms of action. Of particular interest are in vitro screening methods that can document the effects of these endocrine disrupting compounds on fish. In this study, an in vitro bioassay was developed in the roach (Rutilus rutilus) for evaluating the estrogenicity or antiestrogenicity potency of environmental pollutants by measuring vitellogenin (VTG) induction in cultured liver explants. The cell viability was assessed by the measurement of nonspecific esterase activity using a fluorescein diacetate hydrolysis assay. Results showed that explants could be cultured for 72 h without any significant loss of activity. Dose-dependent responses have been measured with estrogenic model compounds such as 17-β-estradiol (E2) and 17-α-ethynylestradiol (EE2) or antiestrogenic compounds such as tamoxifen. Lowest observable effective concentrations were 1 nM for E2, 1 nM for EE2, and 100 nM for tamoxifen, showing a good sensitivity of the test system. Estrogenicity of butyl 4-hydroxybenzoate, 4-nonylphenol, and bisphenol A was tested. bisphenol A (100 μM) or butylparaben induced a twofold increase in VTG production when compared with 100 nM E2, whereas this production was only 20% with 100 μM 4-nonylphenol. Overall, this study shows that the bioassay could provide valuable information on endocrine disrupting chemicals including metabolites and mixtures of compounds. PMID:20549626

  11. Modified hydra bioassay to evaluate the toxicity of multiple mycotoxins and predict the detoxification efficacy of a clay-based sorbent.

    Science.gov (United States)

    Brown, K A; Mays, T; Romoser, A; Marroquin-Cardona, A; Mitchell, N J; Elmore, S E; Phillips, T D

    2014-01-01

    Food shortages and a lack of food supply regulation in developing countries often leads to chronic exposure of vulnerable populations to hazardous mixtures of mycotoxins, including aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)). A refined calcium montmorillonite clay [i.e. uniform particle size NovaSil (UPSN)] has been reported to tightly bind these toxins, thereby decreasing bioavailability in humans and animals. Hence, our objectives in the present study were to examine the ability of UPSN to bind mixtures of AFB(1) and FB(1) at gastrointestinally relevant pH in vitro, and to utilize a rapid in vivo bioassay to evaluate AFB(1) and FB(1) toxicity and UPSN efficacy. Isothermal sorption data indicated tight AFB(1) binding to UPSN surfaces at both pH 2.0 and 6.5, but substantially more FB(1) bound at pH 2.0 than 6.5. Site-specific competition occurred between the toxins when exposed to UPSN in combination. Importantly, treatment with UPSN resulted in significant protection to mycotoxin-exposed hydra maintained at pH 6.9-7.0. Hydra were exposed to FB(1), AFB(1) and FB(1) /AFB(1) combinations with and without UPSN. A toxic response over 92 h was rated based on morphology and mortality. Hydra assay results indicated a minimum effective concentration (MEC) of 20 µg ml(-1) for AFB(1), whereas the MEC for FB(1) was not reached. The MEC for co-exposure was 400 µg ml(-1) FB(1) + 10 µg ml(-1) AFB(1). This study demonstrates that UPSN sorbs both mycotoxins tightly at physiologically relevant pH levels, resulting in decreased bioavailability, and that a modified hydra bioassay can be used as an initial screen in vivo to predict efficacy of toxin-binding agents. PMID:23047854

  12. Assessment of dissolved nutrients dispersal derived from offshore fish-farm using nitrogen stable isotope ratios (δ 15N) in macroalgal bioassays

    Science.gov (United States)

    García-Sanz, T.; Ruiz, J. M.; Pérez, M.; Ruiz, M.

    2011-02-01

    In this study, the dispersal of wastes from offshore fish farms was evaluated by analyzing nitrogen stable isotope ratios (δ 15N) in macroalgae incubated in the water column at sites located at an increasing distance from the fish cages. Bioassays were performed at three fish farms situated in separate localities with different nutritional conditions (Canary Islands, Murcia and Catalonia) and varying in size, species of fish reared and annual production. Macroalgal bioassays were carried out in two different directions (DI and DII) and they were replicated at each distance in order to evaluate the effect of small-scale variability on the spatial extent of fish farm wastes. The results obtained with δ 15N contribute to a better understanding of the application of nitrogen stable isotopes ratios in macroalgae as an effective bioindicator for tracing the dispersion of offshore fish farm wastes, and demonstrate that fish farm wastes can be traced even over distances of some km from the pollution source. In the Canary Islands, the maximum distance obtained for detection of fish farm wastes was between 450 and 700 m. Of the three installations studied, Murcia presented the greatest distance for detection of fish farm waste influence, ranging from between 1550 and 2450 m, whilst in Catalonia this distance was less than 120 m. In Catalonia, the results were masked by the influence of other sources of nitrogen, and thus fish farm wastes were detected at more reduced distances than expected. These results confirm that fish farm wastes can be traced using the nitrogen stable isotope ratios of macroalgae and that this method can also be useful for identifying areas of potential risk to some sensitive ecosystems, and as an early signal that changes in the community structure might occur.

  13. Acute toxicity over Ceriodaphnia silvestrii and Daphnia magna: Bioassays with water samples from a dam under the influence of uranium mine and with manganese

    International Nuclear Information System (INIS)

    Treated effluents from uranium mine with acid mine drainage can impact receiving water bodies. AMD is relevant from the environmental view due to the large volume of effluents generated, known to affect aquatic biota. Studies show that one of the main problems of treated effluents released by UTM/INB on the catchment basin of Ribeirao das Antas is associated to high Mn values in water samples. In this context, acute 48-h toxicity tests with Mn were conducted with Ceriodaphnia silvestrii and Daphnia magna to determine the No Observed Effect Concentration (NOEC) and the Observed Effect Concentration (OEC) in laboratory bioassays and to verify the potential toxicity of the Mn in face of concentrations found in water samples from the Antas Dam, which receives treated effluents from UTM/INB. In this study, preliminary results of acute toxicity for C. silvestrii indicated OEC values between 9.0 and 10.0 mg Mn/L and NOEC < 3.0 mg Mn/L. For D. magna, OEC and NOEC concentrations were ≥ 30 mg Mn/L and ≤ 80 mg Mn/L, respectively. It was verified that Mn concentrations determined in environmental samples registered the highest value at 1.75 mg Mn/L, below the OEC concentrations recorded for both species. Since manganese occurs in the composition of the effluent that may contain other stable and radioactive elements, complementary ecotoxicological tests must be conducted, aiming at the assessment of synergistic and antagonistic effects of the chemical mixture that makes up the radioactive effluents that are treated and released at the Antas Dam. Such bioassays are underway in the Radioecology Laboratory at LAPOC/CNEN. (author)

  14. Body weight considerations in the B6C3F1 mouse and the use of dietary control to standardize background tumor incidence in chronic bioassays

    International Nuclear Information System (INIS)

    In B6C3F1 mice, the rate of body growth influences susceptibility to liver neoplasia and large variations in body weight can complicate the interpretation of bioassay data. The relationship between body weight and liver tumor incidence was calculated for historical control populations of male and female ad libitum-fed mice (approx. 2750 and 2300 animals, respectively) and in populations of male and female mice which had been subjected to forced body weight reduction due to either dietary restriction or exposure to noncarcinogenic chemicals (approx. 1600 and 1700, respectively). Resulting tumor risk data were then used to construct idealized weight curves for male and female B6C3F1 mice; these curves predict a terminal background liver tumor incidence of 15-20%. Use of dietary control to manipulate body growth of male B6C3F1 mice to fit the idealized weight curve was evaluated in a 2-year bioassay of chloral hydrate. Cohorts of mice were successfully maintained at weights approximating their idealized target weights throughout the study. These mice exhibited less body weight variation than their ad libitum-fed counterparts (e.g., standard deviations of body weight were 1.4 and 3.4 g for respective control groups at 36 weeks). Historical control body weight and tumor risk data from the two male mouse populations were utilized to predict background liver tumor rates for each experimental group of the chloral hydrate study. The predicted background tumor rates closely matched the observed rates for both the dietary controlled and ad libitum-fed chloral hydrate control groups when each mouse was evaluated according to either its weekly food consumption or its weekly change in body weight

  15. 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

    Energy Technology Data Exchange (ETDEWEB)

    Hoflack, J-C.; Mueller, L., E-mail: Lutz.Mueller@roche.com; Fowler, S.; Braendli-Baiocco, A.; Flint, N.; Kuhlmann, O.; Singer, T.; Roth, A.

    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 samples 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

  16. 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

    International Nuclear Information System (INIS)

    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 samples 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

  17. NTP Carcinogenesis Bioassay of Propyl Gallate (CAS No. 121-79-9) in F344/N Rats and B6C3F1 Mice (Feed Study).

    Science.gov (United States)

    1982-12-01

    Propyl gallate is a white to nearly white odorless powder having a slightly bitter taste. Solutions of propyl gallate turn dark in the presence of iron or iron salts. Propyl gallate has been used since 1948 as an antioxidant to stabilize cosmetics, food packaging materials, and foods containing fats. As an additive, it may be found in edible fats, oils, mayonnaise, shortening, baked goods, candy, dried meat, fresh pork sausage, and dried milk, and it is used in hair grooming products, pressure-sensitive adhesives, lubricating oil additives, and transforming oils. A NTP Carcinogenesis bioassay of propyl gallate was conducted by feeding diets containing 6,000 or 12,000 ppm propyl gallate to groups of 50 F344/N rats and 50 B6C3F1 mice of each sex for 103 weeks. Groups of 50 untreated rats and 50 untreated mice of each sex served as controls. Survival of rats and mice was not adversely affected by propyl gallate, but mean body weights of dosed rats and mice of each sex were lower than those of the controls. At 104 weeks, mean body weights of low-and high-dose rats were 4% and 8% lower than those of the controls for males and 11% and 19% lower than those of the controls for females. Similarly, mean body weights of low-and high-dose mice were 5% and 8% lower than those of the controls for males and 11% (both dose groups) lower than those of the controls for females. Thyroid follicular-cell adenomas or carcinomas (combined) occurred in male rats with a statistically significant (P<0.05) positive trend, but the incidences in the dosed groups were not statistically significant in direct comparisons with the control groups. Moreover, the incidence of high-dose male rats with follicular-cell tumors (3/50, 6%) was not statistically different from the historical control rate (14/584, 2.4%) for the laboratory that conducted this bioassay. Rare tumors (an astrocytoma or a glioma) were found in the brains of two low-dose female rats. The incidence of all brain tumors in the

  18. Use of Bioassay test for the environmental evaluation of mining residues and their leachates: the singular case of the Portman Bay (SE, Spain)

    Science.gov (United States)

    Martínez-Sánchez, Maria Jose; García-Lorenzo, Maria Luz; Pérez-Sirvent, Carmen; Molina, Jose; Tudela, Maria Luz; Hernández-Córdoba, Manuel

    2010-05-01

    The aim of the present study was to evaluate the toxicity of sediments and their pore-water extracts from sites contaminated by mining activities using two assays: bacteria and plants. The acute toxicity in pore-waters was determined using the Microtox® bioassay, which uses the naturally luminescent marine bacterium Vibrio fischeri. Phytotoxicity in soil samples was tested by way of the seed germination and root elongation technique in three plant species, Sorghum saccharatum, Sinapis alba and Lepidium sativum. The aim of applying these assays is to establish a method for evaluating the real risks within a risk analysis process, considering both present and future risks, bearing in mind that the uses to which soil is put (urban, recreational or industrial) may change. In the zone studied, mining activities have led to heavy metal contamination with the risk of runoff and wind dispersion of the contaminated material. For this study, 6 sediment samples were collected from Portman Bay (Murcia, SE Spain). The soil extract was prepared by saturation with distilled water and allowing it to stand for four hours. Then, the soil was subjected to a vacuum pressure to extract the soil solution through filter paper. The Zn and Fe content was determined by flame atomic absorption spectrometry (FAAS). The Pb, Cd and Cu content was determined by electrothermal atomization atomic absorption spectrometry (ETAAS). The As content was analysed by atomic fluorescence spectrometry using an automated continuous flow hydride generation (As-AFS) spectrometer. Total Pb concentration varied from 600 to 2500 ppm, with a mean value of 1200 ppm. The average content of Zn was 5300 ppm. The mean concentration of Cd and Cu was 23 and 59 ppm, respectively. Total As concentrations varied from 180 to 470 ppm, with an average value 280 ppm. Finally, the total Fe content ranged from 37% to 47%, with an average value of 40%. Pore-water samples showed neutral pH values and average electrical

  19. Assessment of estrogenic and anti-androgenic activities of the mycotoxin zearalenone and its metabolites using in vitro receptor-specific bioassays.

    Science.gov (United States)

    Molina-Molina, José-Manuel; Real, Macarena; Jimenez-Diaz, Inmaculada; Belhassen, Hidaya; Hedhili, Abderazzak; Torné, Pablo; Fernández, Mariana F; Olea, Nicolás

    2014-12-01

    Zearalenone (ZEN) is a well-known mycotoxin present in numerous agricultural products. Humans and animals are therefore at a risk of exposure to zearalenone through consumption of contaminated food. After intake, ZEN is reduced to α- and β-zearalenol (α-ZEL and β-ZEL), zearalanone (ZAN), and α- and β-zearalanol (α-ZAL and β-ZAL). Although their estrogenicity has been well characterized, much less is known about their interaction with other nuclear receptors. This study was undertaken to investigate interactions of ZEN and its five metabolites, with the human androgen receptor (hAR) and estrogen receptor alpha (hERα). Their ability to induce hAR-mediated reporter gene expression was examined in androgen-sensitive PALM cells, whereas the effects on hERα function were assessed in MCF-7 cells using the E-Screen bioassay. We confirm that ZEN and its metabolites are full agonists for hERα and demonstrate that all six compounds tested possess hAR-mediated antagonistic activity in PALM cells, in which ZAN, α-ZAL, and β-ZAL were the most effective hAR antagonists. Overall, the observed estrogenic and anti-androgenic potencies of ZEN and its metabolites suggest that these compounds may interfere with the endocrine system by various modes of action and that further investigation is warranted into their role as endocrine disrupters in animals and humans. PMID:25455890

  20. Reducing the infectivity and richness of ectomycorrhizal fungi in a calcareous Quercus ilex forest through soil preparations for truffle plantation establishment: A bioassay study.

    Science.gov (United States)

    Garcia-Barreda, Sergi; Molina-Grau, Sara; Reyna, Santiago

    2015-11-01

    In the early years of a black truffle plantation, the field proliferation of the nursery-inoculated fungi can be hampered by native ectomycorrhizal fungi colonising the seedling roots. Reducing the soil ectomycorrhizal infectivity in the planting hole before introducing the inoculated seedling could be an effective strategy to reduce this problem. Three bioassays were conducted to evaluate the impact of several soil preparations on the ectomycorrhizal infectivity and richness of a Quercus ilex soil in a truffle-producing region. Microwaves, quicklime, and acetic acid significantly decreased the percent root colonisation and morphotype richness of the native ectomycorrhizal fungi. However, they also decreased seedling survival or growth. Peracetic acid, hydrogen peroxide, and sodium hypochlorite did not show a significant negative effect on the soil ectomycorrhizal community. The results support the potential of soil preparation for reducing the ectomycorrhizal infectivity of forest soils, thus being a promising strategy to reduce the early colonisation by native fungi in truffle plantations. However, the indications of damage to the seedling development must be addressed. PMID:26466886

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

    Science.gov (United States)

    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. PMID:26550921

  2. An in vitro bioassay for the quantitative evaluation of mosquito repellents against Stegomyia aegypti (=Aedes aegypti) mosquitoes using a novel cocktail meal.

    Science.gov (United States)

    Huang, T-H; Tien, N-Y; Luo, Y-P

    2015-09-01

    To assess the efficacy of new insect repellents, an efficient and safe in vitro bioassay system using a multiple-membrane blood-feeding device and a cocktail meal was developed. The multiple-membrane blood-feeding device facilitates the identification of new insect repellents by the high-throughput screening of candidate chemicals. A cocktail meal was developed as a replacement for blood for feeding females of Stegomyia aegypti (=Aedes aegypti) (L.) (Diptera: Culicidae). The cocktail meal consisted of a mixture of salt, albumin and dextrose, to which adenosine triphosphate was added to induce engorging. Feeding rates of St. aegypti on the cocktail meal and pig blood, respectively, did not differ significantly, but were significantly higher than the feeding rate on citrate phosphate dextrose-adenine 1 (CPDA-1) solutions, which had been used to replace bloodmeals in previous repellent assays. Dose-dependent biting inhibition rates were analysed using probit analysis. The RD(50) (the dose producing 50% repellence of mosquito feeding) values of DEET, citronella, carvacrol, geraniol, eugenol and thymol were 1.62, 14.40, 22.51, 23.29, 23.83 and 68.05 µg/cm(2), respectively. PMID:25828787

  3. Repositioning organohalogen drugs: a case study for identification of potent B-Raf V600E inhibitors via docking and bioassay.

    Science.gov (United States)

    Li, Yisu; Guo, Binbin; Xu, Zhijian; Li, Bo; Cai, Tingting; Zhang, Xinben; Yu, Yuqi; Wang, Heyao; Shi, Jiye; Zhu, Weiliang

    2016-01-01

    Drug repositioning has been attracting increasingly attention for its advantages of reducing costs and risks. Statistics showed that around one quarter of the marketed drugs are organohalogens. However, no study has been reported, to the best of our knowledge, to aim at efficiently repositioning organohalogen drugs, which may be attributed to the lack of accurate halogen bonding scoring function. Here, we present a study to show that two organohalogen drugs were successfully repositioned as potent B-Raf V600E inhibitors via molecular docking with halogen bonding scoring function, namely D(3)DOCKxb developed in our lab, and bioassay. After virtual screening by D(3)DOCKxb against the database CMC (Comprehensive Medicinal Chemistry), 3 organohalogen drugs that were predicted to form strong halogen bonding with B-Raf V600E were purchased and tested with ELISA-based assay. In the end, 2 of them, rafoxanide and closantel, were identified as potent inhibitors with IC50 values of 0.07 μM and 1.90 μM, respectively, which are comparable to that of vemurafenib (IC50: 0.17 μM), a marketed drug targeting B-Raf V600E. Single point mutagenesis experiments confirmed the conformations predicted by D(3)DOCKxb. And comparison experiment revealed that halogen bonding scoring function is essential for repositioning those drugs with heavy halogen atoms in their molecular structures. PMID:27501852

  4. Combining passive samplers and biomonitors to evaluate endocrine disrupting compounds in a wastewater treatment plant by LC/MS/MS and bioassay analyses

    International Nuclear Information System (INIS)

    Two types of integrative sampling approaches (passive samplers and biomonitors) were tested for their sampling characteristics of selected endocrine disrupting compounds (EDCs). Chemical analyses (LC/MS/MS) were used to determine the amounts of five EDCs (nonylphenol, bisphenol A, estrone, 17β-estradiol and 17α-ethinylestradiol) in polar organic chemical integrative samplers (POCIS) and freshwater mussels (Unio pictorum); both had been deployed in the influent and effluent of a municipal wastewater treatment plant (WWTP) in Genoa, Italy. Estrogenicity of the POCIS samples was assessed using the yeast estrogen screen (YES). Estradiol equivalent values derived from the bioassay showed a positive correlation with estradiol equivalents calculated from chemical analyses data. As expected, the amount of estrogens and EEQ values in the effluent were lower than those in the influent. Passive sampling proved to be the preferred method for assessing the presence of these compounds since employing mussels had several disadvantages both in sampling efficiency and sample analyses. - Passive sampling and biomonitoring were used to determine the amounts of endocrine disrupting compounds in wastewaters.

  5. Combining passive samplers and biomonitors to evaluate endocrine disrupting compounds in a wastewater treatment plant by LC/MS/MS and bioassay analyses

    Energy Technology Data Exchange (ETDEWEB)

    Liscio, C. [Dipartimento di Chimica e Chimica Industriale, Universita di Genova, via Dodecaneso, 31, 16146 Genova (Italy); Magi, E., E-mail: magie@chimica.unige.i [Dipartimento di Chimica e Chimica Industriale, Universita di Genova, via Dodecaneso, 31, 16146 Genova (Italy); Di Carro, M. [Dipartimento di Chimica e Chimica Industriale, Universita di Genova, via Dodecaneso, 31, 16146 Genova (Italy); Suter, M.J.-F.; Vermeirssen, E.L.M. [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Uberlandstrasse 133, 8600 Duebendorf (Switzerland)

    2009-10-15

    Two types of integrative sampling approaches (passive samplers and biomonitors) were tested for their sampling characteristics of selected endocrine disrupting compounds (EDCs). Chemical analyses (LC/MS/MS) were used to determine the amounts of five EDCs (nonylphenol, bisphenol A, estrone, 17beta-estradiol and 17alpha-ethinylestradiol) in polar organic chemical integrative samplers (POCIS) and freshwater mussels (Unio pictorum); both had been deployed in the influent and effluent of a municipal wastewater treatment plant (WWTP) in Genoa, Italy. Estrogenicity of the POCIS samples was assessed using the yeast estrogen screen (YES). Estradiol equivalent values derived from the bioassay showed a positive correlation with estradiol equivalents calculated from chemical analyses data. As expected, the amount of estrogens and EEQ values in the effluent were lower than those in the influent. Passive sampling proved to be the preferred method for assessing the presence of these compounds since employing mussels had several disadvantages both in sampling efficiency and sample analyses. - Passive sampling and biomonitoring were used to determine the amounts of endocrine disrupting compounds in wastewaters.

  6. Environmental monitoring to the sources of atmospheric emission by the Trad-MCN bioassay and analysis of the accumulative potential for uranium and fluoride

    International Nuclear Information System (INIS)

    The biomonitoring of the atmospheric contamination constitutes important procedure for adoption of environmental control measures. Biological assays have been employed to evaluate genotoxic agents in the atmosphere. The Tradescantia-micronucleus (Trad-MCN) assay has been extensively used in environmental monitoring owing to its efficiency in the detection of chromosomic damages in cytological preparations of easy execution. In this study we tested the viability of use of Trad-MCN with Tradescantia pallida cv. Purpurea for environmental monitoring in the Experimental Center Aramar (CEA), in Ipero - SP and its leaf accumulation capacity. The plants were exposed in situ, in flower-beds or flowerpots, established close to the sources of atmospheric emission. The bioassay was accomplished according to the usual protocol. The micronucleus frequencies were compared using the variance Kruskal-Wallis test. The obtained results indicated that the biomonitoring model adopted was not the ideal for the CEA, considering that the plant suffered the influence of climatic condition. However the plant showed to have accumulative potential for uranium. (author)

  7. Evaluation of Baffle Fixes Film up Flow Sludge Blanket Filtration (BFUSBF System in Treatment of Wastewaters from Phenol and 2,4-Dinitrophenol Using Daphnia Magna Bioassay

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Ghannadzadeh

    2016-02-01

    Full Text Available Background: Phenol and nitrophenol are common compounds found in different types of industrial wastewater known as serious threats to human health and natural environment. In this study, Daphnia magna was used to evaluate the effectiveness of "baffle fixes film up flow sludge blanket filtration" (BFUSBF system in elimination of phenolic compounds from water. Methods: D. magna cultures were used as toxicity index of phenol and 2,4-DNP mixtures after treatment by a pilot BFUSBF system which consisted of baffle in anoxic section and biofilm in aerobic sections. Initial concentrations were 312 mg/L phenol and 288 mg/L 2,4-dinitrophenol (2,4-DNP. Results: Bioassay tests showed that D. magna was influenced by the toxicity of phenol and 2,4 DNP mixtures. The comparison between the toxicity of initial phenol and 2,4-DNP mixtures and the output toxic unit (TU derived from BFUSBF treatment system showed that the TU of the effluent from BFUSBF reactor was much lower than that of the solution that entered the reactor. Conclusion: Based on the acute toxicity test, BFUSBF process could reduce phenol and 2,4-DNP in aqueous solutions. Therefore, it is possible to use BFUSBF process as an appropriate treatment option for wastewaters containing phenolic compounds.

  8. The impact of sediment bioturbation by secondary organisms on metal bioavailability, bioaccumulation and toxicity to target organisms in benthic bioassays: Implications for sediment quality assessment.

    Science.gov (United States)

    Remaili, Timothy M; Simpson, Stuart L; Amato, Elvio D; Spadaro, David A; Jarolimek, Chad V; Jolley, Dianne F

    2016-01-01

    Bioturbation alters the properties of sediments and modifies contaminant bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53-100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment. PMID:26589100

  9. Evaluation of toxic, cytotoxic, mutagenic, and antimutagenic activities of natural and technical cashew nut shell liquids using the Allium cepa and Artemia salina bioassays.

    Science.gov (United States)

    Leite, Aracelli de Sousa; Dantas, Alisson Ferreira; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M; Melo-Cavalcante, Ana Amélia de C; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used. PMID:25861638

  10. Evaluation of Toxic, Cytotoxic, Mutagenic, and Antimutagenic Activities of Natural and Technical Cashew Nut Shell Liquids Using the Allium cepa and Artemia salina Bioassays

    Directory of Open Access Journals (Sweden)

    Aracelli de Sousa Leite

    2015-01-01

    Full Text Available The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL. There are both natural (iCNSL and technical (tCNSL cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O on the meristems’ root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-, during (co-, and after (post- treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used.

  11. Reproductive toxicity assessment of surface water of the Tai section of the Yangtze River, China by in vitro bioassays coupled with chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaoyi [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Jiangsu Academy of Environmental Science, Nanjing 210036 (China); Wu Jiang [Laboratory of Immunology and Reproductive Biology, School of Medicine, Nanjing University, Nanjing 210093 (China); Hao Yingqun [Environmental Monitoring Center of Jiangsu Province, Nanjing 210036 (China); Zhu Bingqing [State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); Shi Wei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Hu Guanjiu [Environmental Monitoring Center of Jiangsu Province, Nanjing 210036 (China); Han Xiaodong [Laboratory of Immunology and Reproductive Biology, School of Medicine, Nanjing University, Nanjing 210093 (China); Giesy, John P. [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan (Canada); Zoology Department, College of Science, King Saud University, Riyadh (Saudi Arabia); Yu Hongxia, E-mail: yuhx@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

    2011-10-15

    Reproductive toxicity of organic extracts of the surface water from the Tai section of the Yangtze River was assessed by in vitro cytotoxity assays and selected persistent organic pollutants including PCBs, OCPs and PAHs were quantified by instrumental analysis. Eleven of the US EPA priority PAHs were detected. Individual PAHs were found to range from 0.7 to 20 ng/L. Concentrations of BaP did not exceed the national drinking water source quality standard of China. However, a 286-fold concentrated organic extract induced significant reproductive toxicity in adult male rats. The morphology of cells, MTT assay and LDH release assay were all affected by exposure to the organic extracts of water. The results of the reproductive toxicity indicated that PAHs posed the greatest risk of the chemicals studied. The compounds present in the water could be bioconcentrated and result in adverse effects. - Highlights: > Only 11 PAHs of US EPA priority PAHs were detected in surface water the Yangtze River. > Level of BaP didn't exceed national drinking water source quality standard of China. > 286-fold concentrated organic extracts induced great reproductive toxicity in rats. > PAHs posed the greatest risk of the chemicals studied. > The compounds in the water could be bioconcentrated and result in adverse effects. - In vitro bioassay responses observed in Yangtze River source water extracts showed great reproductive toxicity, and PAHs were responsible.

  12. Environmental monitoring to the sources of atmospheric emission by the Trad-MCN bioassay and analysis of the accumulative potential for uranium and fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Alessandra C.F.E., E-mail: alessandra@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil). Div. de Monitoracao Ambiental; Ramos, Monique M.B., E-mail: monique@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil). Div. de Analise de Seguranca; Alves, Edenise S., E-mail: ealves@ibot.sp.gov.b [Instituto de Botanica de Sao Paulo, Sao Paulo, SP (Brazil). Secao de Anatomia

    2009-07-01

    The biomonitoring of the atmospheric contamination constitutes important procedure for adoption of environmental control measures. Biological assays have been employed to evaluate genotoxic agents in the atmosphere. The Tradescantia-micronucleus (Trad-MCN) assay has been extensively used in environmental monitoring owing to its efficiency in the detection of chromosomic damages in cytological preparations of easy execution. In this study we tested the viability of use of Trad-MCN with Tradescantia pallida cv. Purpurea for environmental monitoring in the Experimental Center Aramar (CEA), in Ipero - SP and its leaf accumulation capacity. The plants were exposed in situ, in flower-beds or flowerpots, established close to the sources of atmospheric emission. The bioassay was accomplished according to the usual protocol. The micronucleus frequencies were compared using the variance Kruskal-Wallis test. The obtained results indicated that the biomonitoring model adopted was not the ideal for the CEA, considering that the plant suffered the influence of climatic condition. However the plant showed to have accumulative potential for uranium. (author)

  13. Bioassay-guided fractionation of extracts from Codiaeum variegatum against Entamoeba histolytica discovers compounds that modify expression of ceramide biosynthesis related genes.

    Science.gov (United States)

    Mfotie Njoya, Emmanuel; Weber, Christian; Hernandez-Cuevas, Nora Adriana; Hon, Chung-Chau; Janin, Yves; Kamini, Melanie F G; Moundipa, Paul F; Guillén, Nancy

    2014-01-01

    Leaves of Codiaeum variegatum ("garden croton") are used against bloody diarrhoea by local populations in Cameroon. This study aims to search for the active components from C. variegatum against Entamoeba histolytica, and thereby initiate the study of their mechanism of action. A bioassay-guided screening of the aqueous extracts from C. variegatum leaves and various fractions was carried out against trophozoites of E. histolytica axenic culture. We found that the anti-amoebic activity of extracts changed with respect to the collection criteria of leaves. Thereby, optimal conditions were defined for leaves' collection to maximise the anti-amoebic activity of the extracts. A fractionation process was performed, and we identified several sub-fractions (or isolated compounds) with significantly higher anti-amoebic activity compared to the unfractionated aqueous extract. Anti-amoebic activity of the most potent fraction was confirmed with the morphological characteristics of induced death in trophozoites, including cell rounding and lysis. Differential gene expression analysis using high-throughput RNA sequencing implies the potential mechanism of its anti-amoebic activity by targeting ceramide, a bioactive lipid involved in disturbance of biochemical processes within the cell membrane including differentiation, proliferation, cell growth arrest and apoptosis. Regulation of ceramide biosynthesis pathway as a target for anti-amoebic compounds is a novel finding which could be an alternative for drug development against E. histolytica. PMID:24416462

  14. Bioassay-guided fractionation of extracts from Codiaeum variegatum against Entamoeba histolytica discovers compounds that modify expression of ceramide biosynthesis related genes.

    Directory of Open Access Journals (Sweden)

    Emmanuel Mfotie Njoya

    Full Text Available Leaves of Codiaeum variegatum ("garden croton" are used against bloody diarrhoea by local populations in Cameroon. This study aims to search for the active components from C. variegatum against Entamoeba histolytica, and thereby initiate the study of their mechanism of action. A bioassay-guided screening of the aqueous extracts from C. variegatum leaves and various fractions was carried out against trophozoites of E. histolytica axenic culture. We found that the anti-amoebic activity of extracts changed with respect to the collection criteria of leaves. Thereby, optimal conditions were defined for leaves' collection to maximise the anti-amoebic activity of the extracts. A fractionation process was performed, and we identified several sub-fractions (or isolated compounds with significantly higher anti-amoebic activity compared to the unfractionated aqueous extract. Anti-amoebic activity of the most potent fraction was confirmed with the morphological characteristics of induced death in trophozoites, including cell rounding and lysis. Differential gene expression analysis using high-throughput RNA sequencing implies the potential mechanism of its anti-amoebic activity by targeting ceramide, a bioactive lipid involved in disturbance of biochemical processes within the cell membrane including differentiation, proliferation, cell growth arrest and apoptosis. Regulation of ceramide biosynthesis pathway as a target for anti-amoebic compounds is a novel finding which could be an alternative for drug development against E. histolytica.

  15. Development of standardized bioassay protocols for the toxicity assessment of waste, manufactured products, and effluents in Latin America: Venezuela, a Case Study

    International Nuclear Information System (INIS)

    The present status of the toxicity assessment of industrial products in Latin America is well below North America/EC standards. As an example, most of Latin America regulatory laws regarding effluent discharge are still based upon concentration limits of certain major pollutants, and BOD/COD measurements; no reference is made to the necessity of aquatic bioassay toxicity data. Aware of this imperative need, the Venezuelan Petroleum Industry (PDVSA), through its R ampersand D Corporative branch (INTEVEP) gave priority to the development of standardized acute/sublethal toxicity test protocols as sound means of evaluating their products and wastes. Throughout this presentation, the Venezuelan case will be studied, showing strategies undertaken to accelerate protocol development. Results will show the assessment of 14 different protocols encompassing a variety of species of aquatic/terrestrial organisms, and a series of toxicity test endpoints including mortality, reproductive, biological and immunological measurements, most of which are currently in use or being developed. These protocols have already yielded useful results in numerous cases where toxicity assessment was required, including evaluations of effluent, oil dispersants, drilling fluids, toxic wastes, fossil fuels and newly developed products. The Venezuelan case demonstrates that the integration of Industry, Academia and Government, which is an essential part of SETAC's philosophy, is absolutely necessary for the successful advancement of environmental scientific/regulatory issues

  16. Bioassay and ultraperformance liquid chromatography/mass spectrometry guided isolation of apoptosis-inducing benzophenones and xanthone from the pericarp of Garcinia yunnanensis Hu.

    Science.gov (United States)

    Xu, Gang; Feng, Chao; Zhou, Yan; Han, Quan-Bin; Qiao, Chun-Feng; Huang, Sheng-Xiong; Chang, Donald C; Zhao, Qin-Shi; Luo, Kathy Q; Xu, Hong-Xi

    2008-12-10

    Bioassay and ultraperformance liquid chromatography/photodiode array/mass spectrometry (UPLC/PDA/MS) guided isolation of the apoptosis-inducing active metabolites on HeLa-C3 cells from the pericarp of Garcinia yunnanensis (Guttiferae) yielded five active compounds, including the new garciyunnanins A (1) and B (2). The structures of the compounds were elucidated by comprehensive nuclear magnetic resonance and mass spectrometry analysis. Garciyunnanin B (2), featured with a natural tetracyclic xanthone skeleton derived from a polyisoprenylated benzophenone, is structurally interesting since it can be seen as an evidence of the previously described cyclization of garcinol by 2,2-diphenyl-1-picrylhydrazyl (DPPH). Garciyunnanin A (1) contains a 3-monohydroxy benzophenone skeleton, which is rarely found in Garcinia species. Both new compounds induce HeLa-C3 cells into apoptosis after 72 h of incubation at 15 microM. It is noteworthy that oblongifolin C (4), the major constituent of this plant, has proved to be the most active one among the isolates for inducing apoptotic cell death in cervical cancer derived HeLa-C3 sensor cells. PMID:19007298

  17. Consistent increase in dimethyl sulphide (DMS in response to high CO2 in five shipboard bioassays from contrasting NW European waters

    Directory of Open Access Journals (Sweden)

    F. E. Hopkins

    2014-02-01

    Full Text Available The ubiquitous marine trace gas dimethyl sulphide (DMS comprises the greatest natural source of sulphur to the atmosphere and is a key player in atmospheric chemistry and climate. We explore the short term response of DMS and its algal precursor dimethyl sulphoniopropionate (DMSP production and cycling to elevated carbon dioxide (CO2 and ocean acidification (OA in five highly replicated 96 h shipboard bioassay experiments from contrasting sites in NW European shelf waters. In general, the response to OA throughout this region showed little variation, despite encompassing a range of biological and biogeochemical conditions. We observed consistent and marked increases in DMS concentrations relative to ambient controls, and decreases in DMSP concentrations. Quantification of rates of specific DMSP synthesis by phytoplankton and bacterial DMS gross production/consumption suggest algal processes dominated the CO2 response, likely due to a physiological response manifested as increases in direct cellular exudation of DMS and/or DMSP lyase enzyme activities. The variables and rates we report increase our understanding of the processes behind the response to OA. This could provide the opportunity to improve upon mesocosm-derived empirical modelling relationships, and move towards a mechanistic approach for predicting future DMS concentrations.

  18. Consistent increase in dimethyl sulphide (DMS) in response to high CO2 in five shipboard bioassays from contrasting NW European waters

    Science.gov (United States)

    Hopkins, F. E.; Archer, S. D.

    2014-02-01

    The ubiquitous marine trace gas dimethyl sulphide (DMS) comprises the greatest natural source of sulphur to the atmosphere and is a key player in atmospheric chemistry and climate. We explore the short term response of DMS and its algal precursor dimethyl sulphoniopropionate (DMSP) production and cycling to elevated carbon dioxide (CO2) and ocean acidification (OA) in five highly replicated 96 h shipboard bioassay experiments from contrasting sites in NW European shelf waters. In general, the response to OA throughout this region showed little variation, despite encompassing a range of biological and biogeochemical conditions. We observed consistent and marked increases in DMS concentrations relative to ambient controls, and decreases in DMSP concentrations. Quantification of rates of specific DMSP synthesis by phytoplankton and bacterial DMS gross production/consumption suggest algal processes dominated the CO2 response, likely due to a physiological response manifested as increases in direct cellular exudation of DMS and/or DMSP lyase enzyme activities. The variables and rates we report increase our understanding of the processes behind the response to OA. This could provide the opportunity to improve upon mesocosm-derived empirical modelling relationships, and move towards a mechanistic approach for predicting future DMS concentrations.

  19. Assessment of hormone-like activities in Ginkgo biloba, Elettaria cardamomum and Plantago ovata extracts using in vitro receptor-specific bioassays.

    Science.gov (United States)

    Real, Macarena; Molina-Molina, José-Manuel; Jimenez, Jesús; Diéguez, Horacio R; Fernández, Mariana F; Olea, Nicolás

    2015-01-01

    Medicinal plants are widely used for the treatment of diseases and for the development of new drugs. This study was designed to determine the presence of hormone-like activities dependent on the activation of human estrogen receptor alpha (hERa) and/or androgen receptor (hAR) in methanol extracts prepared from three medicinal plants historically and currently used for therapeutic purposes: Ginkgo biloba leaves (GBL), Elettaria cardamomum seeds (ECS) and Plantago ovata seeds (POS). After a solid-liquid extraction (SLE) step, their effects on hERa function were assessed in MCF-7 breast cancer cells using the E-Screen bioassay, and their ability to induce hAR-mediated reporter gene expression was evaluated using the androgen-sensitive stable prostatic PALM cell line. Unlike POS extracts, GBL and ECS extracts showed estrogenic (0.07 and 0.20 nM E2Eq mg(-1), respectively) and anti-estrogenic (0.01 and 0.02 μM ICI182780Eq mg(-1), respectively) activities. ECS extracts evidenced androgenic activity (0.30 nM R1881Eq mg(-1)) and POS extracts anti-androgenic activity (22.30 μM ProcEq mg(-1)). According to these findings, these plant extracts may interfere with the endocrine system via one or more hormonal receptors, and further investigation is warranted into their role as endocrine disrupters in humans. PMID:26161806

  20. Estimation of Median Lethal Concentration of Three Isolates of Beauveria bassiana for Control of Megacopta cribraria (Heteroptera: Plataspidae) Bioassayed on Solid Lygus spp. Diet.

    Science.gov (United States)

    Portilla, Maribel; Jones, Walker; Perera, Omaththage; Seiter, Nick; Greene, Jeremy; Luttrell, Randall

    2016-01-01

    The kudzu bug, Megacopta cribraria (F.), is an urban nuisance and significant agricultural pest. The median lethal concentrations of three strains of Beauveria bassiana (Balsamo), including the Mississippi Delta native strain (NI8) isolated from Lygus lineolaris (Palisot de Beauvois), the commercial strain BotaniGard(®) (GHA) (Victor, NY, USA), and the B. bassiana strain isolated from M. cribraria (KUDSC), were estimated on kudzu bug adults. A technique developed to evaluate B. bassiana against L. lineolaris was used. Younger adults (eight days after collection) were treated with NI8 and GHA and older adult (50 days after collection) were treated with NI8, GHA and KUDSC. Higher concentrations (n × 10⁶, n × 10⁷) of NI8 and GHA caused kudzu bug mortality two days after treatment in younger adults and similar concentrations of NI8, GHA, and KUDSC caused mortality one day after treatment in older adults. Lower concentrations (n × 10⁴, n × 10⁵) were not significantly different in mortality between strains. LS50 values of the KUDSC were significantly lower than NI8 and GHA values in older adults. This is the first available information on median lethal concentration of B. bassiana on kudzu bug adults bioassayed on artificial diet. It was determined that B. bassiana (KUDSC and NI8) are highly effective for young adults at very low doses (LC50 1.98-4.98 viable spores per mm²). PMID:27376335