WorldWideScience

Sample records for repeated toxicity tests

  1. Repeated dose 90-day oral toxicity test of G-7% NANA in rats: An application of new criterion for toxicity determination to test article-induced changes.

    Science.gov (United States)

    Heo, Hye Seon; An, MinJi; Lee, Ji Sun; Kim, Hee Kyong; Park, Yeong-Chul

    2018-06-01

    G-7% NANA is N-acetylneuraminic acid(NANA) containing 7% sialic acid isolated from glycomacropeptide (GMP), a compound of milk. Since NANA is likely to have immunotoxicity, the need to ensure safety for long-term administration has been raised. In this study, a 90-day repeated oral dose toxicity test was performed in rats using G-7% NANA in the dosages of 0, 1250, 2500 and 5000 mg/kg/day.A toxicity determination criterion based on the significant change caused by the administration of the substancewas developed for estimating NOEL, NOAEL and LOAELapplied to this study. When analyzing the immunological markers, no significant changes were observed, even if other significant changes were observed in the high dose group. In accordance with the toxicity determination criterion developed, the NOEL in male and female has been determined as 2500 mg/kg/day, and the NOAEL in females has been determined as 5000 mg/kg/day. The toxicity determination criterion, applied for the first time in the repeated dose toxicity tests, could provide a basis for distinguishing NOEL and NOAEL more clearly; nevertheless, the toxicity determination criterion needs to be supplemented by adding differentiating adverse effects and non-adverse effects based on more experiences of the repeated dose toxicity tests. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Study of four week repeated dose toxic test of Sweet Bee Venom in Beagle Dogs

    Directory of Open Access Journals (Sweden)

    Jae-Seuk Park

    2010-12-01

    Full Text Available Objectives: This study was performed to analyse four week repeated dose toxicity of Sweet Bee Venom(Sweet BV extracted from the bee venom in Beagle dogs. Methods: All experiments were conducted under the regulations of Good Laboratory Practice (GLP at Biotoxtech Company, a non-clinical study authorized institution. Male and female Beagle dogs of 5-6 months old were chosen for the pilot study of four week repeated dose toxicity of Sweet BV which was administered at the level of 0.56㎎/㎏ body weight which is eighty times higher than the clinical application dosage as the high dosage, followed by 0.28 and 0.14㎎/㎏ as midium and low dosage, respectively. Equal amount of excipient(normal saline to the Sweet BV experiment groups was administered as the control group every day for four weeks. Results: 1. No mortality was witnessed in all of the experiment groups. 2. All experiment groups were appealed pain sense in the treating time compared to the control group, and hyperemia and movement disorder were observed around the area of administration in all experiment groups, and higher occurrence in the higher dosage treatment. 3. For weight measurement, Neither male nor female groups showed significant changes. 4. In the urine analysis, CBC and biochemistry didn't show any significant changes in the experiment groups compared with control group. 5. For weight measurement of organs, experiment groups didn't show any significant changes compared with control group. 6. To verify abnormalities of organs and tissues, thigh muscle which treated with Sweet BV, cerebrum, liver, lung, kidney, and spinal cords were removed and conducted histologocal observation with H-E staining. In the histologocal observation of thigh muscle, cell infiltration, inflammatory, degeneration, necrosis of muscle fiber, and fibrosis were found in both thigh tissue. And the changes were depend on the dose of Sweet BV. But another organs were not detected in any abnormalities. 7

  3. The ToxBank Data Warehouse: Supporting the Replacement of In Vivo Repeated Dose Systemic Toxicity Testing.

    Science.gov (United States)

    Kohonen, Pekka; Benfenati, Emilio; Bower, David; Ceder, Rebecca; Crump, Michael; Cross, Kevin; Grafström, Roland C; Healy, Lyn; Helma, Christoph; Jeliazkova, Nina; Jeliazkov, Vedrin; Maggioni, Silvia; Miller, Scott; Myatt, Glenn; Rautenberg, Michael; Stacey, Glyn; Willighagen, Egon; Wiseman, Jeff; Hardy, Barry

    2013-01-01

    The aim of the SEURAT-1 (Safety Evaluation Ultimately Replacing Animal Testing-1) research cluster, comprised of seven EU FP7 Health projects co-financed by Cosmetics Europe, is to generate a proof-of-concept to show how the latest technologies, systems toxicology and toxicogenomics can be combined to deliver a test replacement for repeated dose systemic toxicity testing on animals. The SEURAT-1 strategy is to adopt a mode-of-action framework to describe repeated dose toxicity, combining in vitro and in silico methods to derive predictions of in vivo toxicity responses. ToxBank is the cross-cluster infrastructure project whose activities include the development of a data warehouse to provide a web-accessible shared repository of research data and protocols, a physical compounds repository, reference or "gold compounds" for use across the cluster (available via wiki.toxbank.net), and a reference resource for biomaterials. Core technologies used in the data warehouse include the ISA-Tab universal data exchange format, REpresentational State Transfer (REST) web services, the W3C Resource Description Framework (RDF) and the OpenTox standards. We describe the design of the data warehouse based on cluster requirements, the implementation based on open standards, and finally the underlying concepts and initial results of a data analysis utilizing public data related to the gold compounds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Study on a 4-Week Recovery Test of Sweet Bee Venom after a 13-Week, Repeated, Intramuscular Dose Toxicity Test in Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Chungsan Lim

    2014-06-01

    Full Text Available Objectives:This study was performed to check for reversibility in the changes induced by a 13-week, repeated, dose toxicity test of Sweet Bee Venom (SBV in Sprague-Dawley (SD rats. Methods:Fifteen male and 15 female SD rats were treated with 0.28 mg/kg of SBV (high-dosage group and the same numbers of male and female SD rats were treated with 0.2 mL/kg of normal saline (control group for 13 weeks. We selected five male and five female SD rats from the high-dosage group and the same numbers of male and female SD rats from the control group, and we observed these rats for four weeks. We conducted body-weight measurements, ophthalmic examinations, urinalyses and hematology, biochemistry, histology tests. Results:(1 Hyperemia and movement disorder were observed in the 13-week, repeated, dose toxicity test, but these symptoms were not observed during the recovery period. (2 The rats in the high-dose group showed no significant changes in weight compared to the control group. (3 No significant differences in the ophthalmic parameters, urine analyses, complete blood cell counts (CBCs, and biochemistry were observed among the recovery groups. (4 No changes in organ weights were observed during the recovery period. (5 Histological examination of the thigh muscle indicated cell infiltration, inflammation, degeneration, necrosis of muscle fiber, and fibrosis during the treatment period, but these changes were not observed during the recovery period. The fatty liver change that was observed during the toxicity test was not observed during the recovery period. No other organ abnormalities were observed. Conclusion:The changes that occurred during the 13-week, repeated, dose toxicity test are reversible, and SBV can be safely used as a treatment modality.

  5. Study of four weeks repeated-dose toxic test of Sweet Bee Venom in rats Original Articles

    Directory of Open Access Journals (Sweden)

    Kwon Hae-Yon

    2011-03-01

    Full Text Available Objectives: This study was performed to analyse four weeks repeated -dose toxicity of Sweet Bee Venom (SBV-pure melittin, the major component of honey bee venom in rats. Methods: All experiments were conducted under the regulations of Good Laboratory Practice (GLPat Biotoxtech Company, a non-clinical study authorized institution. Male and female rats of 5 weeks old were chosen for the pilot study of four weeks repeated-dose toxicity and was injected at the level of 0.56 mg/kg body weight (eighty times higher than the clinical application dosage as the high dosage, followed by 0.28 and 0.14 mg/kg as midium and low dosage, respectively. Equal amount of normal saline was injected as the control group every day for four weeks. Results: 1. No mortality was witnessed in all of the experiment groups. 2. All experiment groups appealed pain sense in the treating time compared to the control group, and side effects such as hyperemia and movement disorder were observed around the area of injection in all experiment groups, and the higher dosage in treatment, the higher occurrence in side effects. 3. Concerning weight measurement, neither male nor female groups showed significant changes compared to the control group. 4. Concerning to the CBC and biochemistry, all experiment groups didn't show any significant changes compared to the control group. 5. Concerning weight measurement of organs, experiment groups didn't show any significant changes compared to the control group. 6. To verify abnormalities of organs and tissues, those such as cerebellum, cerebrum, liver, lung, kidney,and spinal cords were removed and we conducted histologocal observation with H-E staining.Concerning the histologocal observation of liver tissues, some fatty changes were observed around portal vein in 0.56 mg/kg experiment group. But another organs were not detected in any abnormalities. 7. The proper high dosage of SBV for the thirteen weeks repeated test in rats may be 0.28 mg

  6. Repeated Intramuscular-dose Toxicity Test of Water-soluble Carthami Flos (WCF Pharmacopuncture in Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Yoo-min Choi

    2015-03-01

    Full Text Available Objectives: Water-soluble carthami flos (WCF is a new mixture of Carthami flos (CF pharmacopuncture. We conducted a 4-week toxicity test of repeated intramuscular injections of WCF in Sprague-Dawley rats. Methods: Forty male and 40 female rats were divided into 4 groups of 10 male and 10 female SD rats: The control group received 0.5 mL/animal/day of normal saline whereas the three experimental groups received WCF at doses of 0.125, 0.25, and 0.5 mL/animal/day, respectively. For 4 weeks, the solutions were injected into the femoral muscle of the rats alternating from side to side. Clinical signs, body weights, and food consumption were observed; opthalmological examinations and urinalyses were performed. On day 29, blood samples were taken for hematological and clinical chemistry analyses. Then, necropsy was conducted in all animals to observe weights and external and histopathological changes in the bodily organs. All data were tested using a statistical analysis system (SAS. Results: No deaths were observed. Temporary irregular respiration was observed in male rats of the experimental group for the first 10 days. Body weights, food consumptions, opthalmological examinations, urinalyses, clinical chemistry analyses, organ weights and necropsy produced no findings with toxicological meaning. In the hematological analysis, delay of prothrombin time (PT was observed in male rats of the 0.25- and the 0.5-mL/animal/day groups. In the histopathological test, a dose-dependent inflammatory cell infiltration into the fascia and panniculitis in perimuscular tissues was observed in all animals of the experimental groups. However, those symptoms were limited to local injection points. No toxicological meanings, except localized changes, were noted. Conclusion: WCF solution has no significant toxicological meaning, but does produce localized symptoms. No observed adverse effect level (NOAEL of WCF in male and female rats is expected for doses over 0.5 mL/animal/day.

  7. [Toxicity studies of landiolol hydrochloride (ONO-1101) (2). 4-week repeated dose intravenous toxicity study in rats with 4-week recovery test].

    Science.gov (United States)

    Yamaguchi, K; Yanagi, H; Shimizu, K; Sakai, M; Nishibata, K; Oida, H; Shinomiya, K; Suzuki, Y; Yonezawa, H; Fujita, T

    1997-12-01

    4-week repeated dose toxicity study with 4-week recovery test of landiolol hydrochloride (ONO-1101), a novel ultra short acting beta-blocker, was conducted in Sprague-Dawley (SD) rats. ONO-1101 was administered intravenously to rats of both sexes at a dose level of 0 (control), 12.5, 25, 50 or 100 mg/kg/day. In the 100 mg/kg/day group, bradypnea or dyspnea was seen in all animals, pale in ear, eye and foot, tremor, reddish lacrimation and loss of righting reflex were also observed in some animals right after administration, and then those signs disappeared within 1 min after administration. During the treatment period, 3/20 animals of each sex in the 100 mg/kg/day showed clonic convulsion and died within 2 min after administration. No clinical changes were seen in the 50 mg/kg/day group or lower. Histopathological findings showed atrophy of the submaxillary gland in females and vessel-wall thickening and perivascular fibrosis of the injection site (tail) in both sexes at 100 mg/kg/day, however those changes were reversible. ONO-1101 did not effect on body weight, food consumption, ophthalmology, urinalysis, hematology, blood chemistry, organ weights or necropsy at any doses. These results indicate that the no-adverse-effect level of ONO-1101 in rats is 50 mg/kg/day for both sexes in this study.

  8. Study of a 13-weeks, Repeated, Intramuscular Dose, Toxicity Test of Sweet Bee Venom in Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Hyunmin Kang

    2014-06-01

    Full Text Available Objectives:This study was performed to analyze a 13-week repeated dose toxicity test of Sweet Bee Venom (SBV extracted from bee venom and administered in Sprague-Dawley (SD rats. Methods:Male and female 5-week-old SD rats were treated once daily with SBV (high-dosage group: 0.28 mg/kg; medium-dosage group: 0.14 mg/kg; or low-dosage group: 0.07 mg/kg for 13 weeks. Normal saline was administered to the control group in a similar manner (0.2 mL/kg. We conducted clinical observations, body weight measurements, ophthalmic examinations, urinalyses, hematology and biochemistry tests, and histological observations using hematoxylin and eosin (H&E staining to identify any abnormalities caused by the SBV treatment. Results:During this study, no mortality was observed in any of the experimental groups. Hyperemia and a movement disorder were observed around the area of in all groups that received SBV treatment, with a higher occurrence in rats treated with a higher dosage. Male rats receiving in the high-dosage group showed a significant decrease in weight during the treatment period. Compared to the control group, no significant changes in the ophthalmic parameters, the urine analyses, the complete blood cell count (CBC, and the biochemistry in the groups treated with SBV. Compared to the control group, some changes in organ weights were observed in the medium-and the high-dosage groups, but the low-dosage group showed no significant changes. Histological examination of thigh muscle indicated cell infiltration, inflammation, degeneration, and necrosis of muscle fiber, as well as fibrosis, in both the medium- and the high-dosage groups. Fatty liver change was observed in the periportal area of rats receiving medium and high dosages of SBV. No other organ abnormalities were observed. Conclusion:Our findings suggest that the No Observed Adverse Effect Level (NOAEL of SBV is approximately 0.07 mg/kg in male and female SD rats.

  9. Portable, accurate toxicity testing

    International Nuclear Information System (INIS)

    Sabate, R.W.; Stiffey, A.V.; Dewailly, E.L.; Hinds, A.A.; Vieaux, G.J.

    1994-01-01

    Ever tightening environmental regulations, severe penalties for non-compliance, and expensive remediation costs have stimulated development of methods to detect and measure toxins. Most of these methods are bioassays that must be performed in the laboratory; none previously devised has been truly portable. The US Army, through the Small Business Innovative Research program, has developed a hand-held, field deployable unit for testing toxicity of battlefield water supplies. This patented system employs the measurable quenching, in the presence of toxins, of the natural bioluminescence produced by the marine dinoflagellate alga Pyrocystis lunula. The procedure's inventor used it for years to measure toxicity concentrations of chemical warfare agents actually, their simulants, primarily in the form of pesticides and herbicides plus assorted toxic reagents, waterbottom samples, drilling fluids, even blood. While the procedure is more precise, cheaper, and faster than most bioassays, until recently it was immobile. Now it is deployable in the field. The laboratory apparatus has been proven to be sensitive to toxins in concentrations as low as a few parts per billion, repeatable within a variation of 10% or less, and unlike some other bioassays effective in turbid or colored media. The laboratory apparatus and the hand-held tester have been calibrated with the EPA protocol that uses the shrimplike Mysidopsis bahia. The test organism tolerates transportation well, but must be rested a few hours at the test site for regeneration of its light-producing powers. Toxicity now can be measured confidently in soils, water columns, discharge points, and many other media in situ. Most significant to the oil industry is that drilling fluids can be monitored continuously on the rig

  10. Repeated 28-day oral toxicity study of vinclozolin in rats based on the draft protocol for the "Enhanced OECD Test Guideline No. 407" to detect endocrine effects.

    Science.gov (United States)

    Shin, Jae-Ho; Moon, Hyun Ju; Kim, Tae Sung; Kang, Il Hyun; Ki, Ho Yeon; Choi, Kwang Sik; Han, Soon Young

    2006-09-01

    We performed a 28-day repeated-dose toxicity study of vinclozolin, a widely used fungicide, based on the draft protocol of the "Enhanced OECD Test Guideline 407" (Enhanced TG407) to investigate whether vinclozolin has endocrine-mediated properties according to this assay. Seven-week-old SD rats were administered with vinclozolin daily by oral gavage at dose rates of 0, 3.125, 12.5, 50 and 200 mg/kg/day for at least 28 days. The vinclozolin-treated male rats showed a reduction of epididymis and accessory sex organ weights and an alteration of hormonal patterns. A slight prolongation of the estrous cycle and changes in the estrogen/testosterone ratio and luteinizing hormone level were observed in vinclozolin-treated female rats. Thyroxin concentrations were decreased and thyroid-stimulating hormone concentrations were increased in both sexes; however, there were no compound-related microscopic lesions in the thyroid gland or changes in the thyroid weight. The endocrine-related effects of vinclozolin could be detected by the parameters examined in the present study based on the OECD protocol, suggesting the Enhanced TG407 protocol should be a suitable screening test for the detection of endocrine-mediated effects of chemicals.

  11. Linear Synchronous Motor Repeatability Tests

    International Nuclear Information System (INIS)

    Ward, C.R.

    2002-01-01

    A cart system using linear synchronous motors was being considered for the Plutonium Immobilization Plant (PIP). One of the applications in the PIP was the movement of a stack of furnace trays, filled with the waste form (pucks) from a stacking/unstacking station to several bottom loaded furnaces. A system was ordered to perform this function in the PIP Ceramic Prototype Test Facility (CPTF). This system was installed and started up in SRTC prior to being installed in the CPTF. The PIP was suspended and then canceled after the linear synchronous motor system was started up. This system was used to determine repeatability of a linear synchronous motor cart system for the Modern Pit Facility

  12. Toxicity Estimation Software Tool (TEST)

    Science.gov (United States)

    The Toxicity Estimation Software Tool (TEST) was developed to allow users to easily estimate the toxicity of chemicals using Quantitative Structure Activity Relationships (QSARs) methodologies. QSARs are mathematical models used to predict measures of toxicity from the physical c...

  13. A Miniscale Algal Toxicity Test

    DEFF Research Database (Denmark)

    Arensberg, Pia; Hemmingsen, Vicky H.; Nyholm, Niels

    1995-01-01

    A simple miniscale (approx. 1 - 2.5 ml) toxicity test procedure with the freshwater green algaSelenastrum capricornutum is described. The procedure fulfils the validity criteria of the ISO (International Association for Standardization) standard test protocol. Practically identical concentration-...... days to 2 days (minitest as well as larger volume tests) in order to avoid excessive biomass growth. Shortening tests to 2 days appears necessary if light intensity and temperature are near the upper limits of the intervals stated in the ISO standard.......A simple miniscale (approx. 1 - 2.5 ml) toxicity test procedure with the freshwater green algaSelenastrum capricornutum is described. The procedure fulfils the validity criteria of the ISO (International Association for Standardization) standard test protocol. Practically identical concentration......-response curves were obtained with the ISO standard test and the minitest for potassium dichromate and 3,5-dichlorophenol. The minitest is conveniently carried out using 2.5 ml test volume in 20 ml glass scintillation vials, placed on a microplate shaker or on an ordinary shaking table, but smaller containers...

  14. Reproductive toxicity testing of vaccines

    International Nuclear Information System (INIS)

    Verdier, Francois; Barrow, Paul C.; Burge, Joeelle

    2003-01-01

    Vaccines play a major role in the prevention of human birth defects by protecting the pregnant woman from teratogenic or otherwise harmful infections. Until now, it has not been common practice to perform preclinical developmental toxicity tests for new vaccines. Despite the excellent safety record of vaccines, increased attention is now being given to the feasibility of screening new vaccines for developmental hazards in animals before their use in humans. Contrary to previous assumptions, many vaccines are now given to potentially pregnant women. Any new components of the vaccine formulation (adjuvants, excipients, stabilisers, preservatives, etc...) could also be tested for influences on development, although based on past experience the risks are limited by the very low dosages used. The conferred immunity following vaccination lasts for several years. Therefore, the developing conceptus may theoretically be exposed to the induced antibodies and/or sensitised T-cells, even if the pregnant woman was last vaccinated during childhood (particularly if she encounters the antigen during pregnancy through exposure to infection). However, it should be kept in mind that viral or bacterial infections represent a higher risk for a pregnant woman than the potential adverse effects related to vaccination or the associated immune response. Non-clinical safety studies may be employed as an aid for hazard identification. In these studies interactions of the vaccine with the maternal immune system or with the developmental systems of the offspring are considered. Post-natal examinations are necessary to detect all possible manifestations of developmental toxicity, such as effects on the immune system. Species selection for the preclinical studies is based on immunogenicity to the vaccine and the relative timing and rate of transfer of maternal antibodies to the offspring. A single study design is proposed for the pre- and post-natal developmental assessments of vaccines in

  15. Repeatability study of replicate crash tests: A signal analysis approach.

    Science.gov (United States)

    Seppi, Jeremy; Toczyski, Jacek; Crandall, Jeff R; Kerrigan, Jason

    2017-10-03

    To provide an objective basis on which to evaluate the repeatability of vehicle crash test methods, a recently developed signal analysis method was used to evaluate correlation of sensor time history data between replicate vehicle crash tests. The goal of this study was to evaluate the repeatability of rollover crash tests performed with the Dynamic Rollover Test System (DRoTS) relative to other vehicle crash test methods. Test data from DRoTS tests, deceleration rollover sled (DRS) tests, frontal crash tests, frontal offset crash tests, small overlap crash tests, small overlap impact (SOI) crash tests, and oblique crash tests were obtained from the literature and publicly available databases (the NHTSA vehicle database and the Insurance Institute for Highway Safety TechData) to examine crash test repeatability. Signal analysis of the DRoTS tests showed that force and deformation time histories had good to excellent repeatability, whereas vehicle kinematics showed only fair repeatability due to the vehicle mounting method for one pair of tests and slightly dissimilar mass properties (2.2%) in a second pair of tests. Relative to the DRS, the DRoTS tests showed very similar or higher levels of repeatability in nearly all vehicle kinematic data signals with the exception of global X' (road direction of travel) velocity and displacement due to the functionality of the DRoTS fixture. Based on the average overall scoring metric of the dominant acceleration, DRoTS was found to be as repeatable as all other crash tests analyzed. Vertical force measures showed good repeatability and were on par with frontal crash barrier forces. Dynamic deformation measures showed good to excellent repeatability as opposed to poor repeatability seen in SOI and oblique deformation measures. Using the signal analysis method as outlined in this article, the DRoTS was shown to have the same or better repeatability of crash test methods used in government regulatory and consumer evaluation test

  16. Acute toxicity and the 28-day repeated dose study of a Siddha medicine Nuna Kadugu in rats

    Directory of Open Access Journals (Sweden)

    Ramaswamy Ramaswamy

    2012-10-01

    Full Text Available Abstract Background Nuna Kadugu (NK, a Siddha medicine prepared from leaves and fruits of Morinda Pubescens, used for the treatment of various skin diseases. Though NK has been widely used for several decades, no scientific report was available on its safety. Present study was undertaken to demonstrate the oral toxicity of NK in Sprague Dawley rats. Methods Acute and 28-day repeated oral toxicity studies were performed following OECD test guidelines 423 and 407, respectively, with minor modifications. In acute oral toxicity study, NK was administered at 2000mg/kg b.wt., p.o and animals were observed for toxic signs at 0, 0.5, 1, 4, 24 h and for next 14 days. Gross pathology was performed at the end of the study. In repeated dose, the 28- day oral toxicity study, NK was administered at 300, 600 and 900 mg/kg b.wt./p.o/day. Two satellite groups (control and high dose were also maintained to determine the delayed onset toxicity of NK. Animals were observed for mortality, morbidity, body weight changes, feed and water intake. Haematology, clinical biochemistry, electrolytes, gross pathology, relative organ weight and histopathological examination were performed. Results In acute toxicity study, no treatment related death or toxic signs were observed with NK administration. In the repeated dose study, no significant differences in body weight changes, food / water intake, haematology, clinical biochemistry and electrolytes content were observed between control and NK groups. No gross pathological findings and difference in relative organ weights were observed between control and NK treated rats. Histopathological examination revealed no abnormalities with NK treatment. Conclusion Acute study reveals that the LD50 of NK is greater than 2000mg/kg, b.wt. in fasted female rats and can be classified as Category 5. 28-day repeated oral toxicity demonstrates that the No Observed Adverse Effect Level of NK is greater than 900 mg/kg b.wt./day, p.o in rats

  17. Impact of Inclusion or Exclusion of Repeaters on Test Equating

    Science.gov (United States)

    Puhan, Gautam

    2011-01-01

    This study examined the effect of including or excluding repeaters on the equating process and results. New forms of two tests were equated to their respective old forms using either all examinees or only the first timer examinees in the new form sample. Results showed that for both tests used in this study, including or excluding repeaters in the…

  18. A study on the repeatability of ultrasonic testing data

    International Nuclear Information System (INIS)

    Yoshimura, Seiichi; Fukumoto, Hiroshi

    1980-01-01

    Reliability improvement of ultrasonic testing data is strongly desired in ultrasonic testing working of nuclear power plants. This paper deals with the problems of the testing by the manual and the remote control apparatus, and with the factors which influence the repeatability of ultrasonic testing data. Following results are found in it. (1) In the testing by the manual, working time and posture influence the repeatability of testing data. (2) Glycerin in suitable for the couplant in the respect of the repeatability of testing data. In the case of using machine oil, the pressure to the probe necessitates to be over 0.2 kg/cm 2 . (3) In the testing by the remote control apparatus, working time, working environment and defect position does not influence the repeatability of testing data. (author)

  19. Local toxicity of benzalkonium chloride in ophthalmic solutions following repeated applications.

    Science.gov (United States)

    Okahara, Akihiko; Kawazu, Kouichi

    2013-01-01

    We performed repeated toxicity studies of benzalkonium chloride (BAK)-containing vehicles of ophthalmic solutions in monkeys and rabbits to assess the local toxicity of BAK after repeated applications on the ocular surface. Local toxicity of BAK was evaluated by toxicity studies in which a 0.01% BAK-containing vehicle was applied twice/day for 52 weeks, 4 times/day for 39 weeks, or 6 times/day for 13 weeks, or in which a 0.005% BAK-containing vehicle was applied 6 times/day for 52 weeks or twice/day for 4 weeks in monkeys. Local toxicity of BAK was also evaluated where a 0.01% BAK-containing vehicle was applied 6 times/day for 6 weeks, or a 0.005% BAK-containing vehicle was applied twice/day for 39 weeks or 8 times/day for 4 weeks in rabbits. These doses were chosen because BAK is generally used at concentrations up to 0.01% in ophthalmic solutions. The BAK-containing vehicle did not cause ophthalmological changes suggestive of irritation, allergy, or corneal damage. We also did not observe any histopathological changes in the eyeball, eyelid, lacrimal gland, and nasal cavity, with repeated applications of BAK for up to 52 weeks, up to 8 times/day, or at concentrations up to 0.01%, in monkeys and rabbits. Our results suggest that BAK in concentrations up to 0.01% in ophthalmic solution is non-toxic to the eyeball, its accessory organs, and the nasal cavity after long repeated applications.

  20. Rethinking developmental toxicity testing: Evolution or revolution?

    NARCIS (Netherlands)

    Scialli, Anthony R; Daston, George; Chen, Connie; Coder, Prägati S; Euling, Susan Y; Foreman, Jennifer; Hoberman, Alan M; Hui, Julia; Knudsen, Thomas; Makris, Susan L; Morford, LaRonda; Piersma, Aldert H; Stanislaus, Dinesh; Thompson, Kary E

    2018-01-01

    Current developmental toxicity testing adheres largely to protocols suggested in 1966 involving the administration of test compound to pregnant laboratory animals. After more than 50 years of embryo-fetal development testing, are we ready to consider a different approach to human developmental

  1. A flow-cytometric NK-cytotoxicity assay adapted for use in rat repeated dose toxicity studies

    International Nuclear Information System (INIS)

    Marcusson-Staahl, Maritha; Cederbrant, Karin

    2003-01-01

    A recent regulatory document for immunotoxicity testing of new pharmaceutical drugs includes cytotoxic natural killer (NK)-cell function as a required parameter in repeated dose toxicity studies. The classical 51 Cr-release assay is the conventional test for cytotoxicity testing but several drawbacks with this assay has increased the demand for new reliable test systems. Here, we describe the optimisation of a flow-cytometric cytotoxicity assay especially adapted for regulatory rat studies in drug development. The test principle is based on target cell labelling with 5-(6)-carboxy-fluorescein succinimidyl ester (CFSE) and subsequent DNA-labelling with propidium iodide (PI) for identification of target cells with compromised cell membranes. The results are expressed as percentage of dead targets on a cell-to-cell basis. The final format of the assay includes 0.5 ml peripheral blood, 1.25x10 5 effector cells per sample, and collection of 500 target events by flow-cytometry. When NKR-P1+ cells were removed from the effector cell population by magnetic depletion the relative proportion decreased from 6 to 0.08%. The corresponding cytotoxic activity decreased from 68 to 8%. Also, the cytotoxic activity showed a significant and positive correlation with the proportion of NK-cells present in the effector cell suspension. Thus, the cytotoxicity measured is almost exclusively exerted by NK-cells. The current flow-cytometric test benefits from using peripheral blood as a source for effector cells since it will not conflict with the use of spleen for histopathological investigations in repeated dose toxicity studies. Additionally, since only a minimal number of effector cells are required per sample repeated testing of the same animal is enabled

  2. Animal alternatives for whole effluent toxicity testing ...

    Science.gov (United States)

    Since the 1940s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that toxicity based effluent assessments and subsequent discharge controls became globally important, when it was recognized that physical and chemical measurements alone did not protect the environment from potential impacts. Consequently, various strategies using different toxicity tests, whole effluent assessment techniques (incorporating bioaccumulation potential and persistence) plus supporting analytical tools have been developed over 30 years of practice. Numerous workshops and meetings have focused on effluent risk assessment through ASTM, SETAC, OSPAR, UK competent authorities, and EU specific country rules. Concurrent with this drive to improve effluent quality using toxicity tests, interest in reducing animal use has risen. The Health and Environmental Sciences Institute (HESI) organized and facilitated an international workshop in March 2016 to evaluate strategies for concepts, tools, and effluent assessments and update the toolbox of for effluent testing methods. The workshop objectives were to identify opportunities to use a suite of strategies for effluents, and to identify opportunities to reduce the reliance on animal tests and to determine barriers to implementation of new methodologie

  3. The effect of repeated testing vs repeated practice on skills learning in undergraduate dental education.

    Science.gov (United States)

    Sennhenn-Kirchner, S; Goerlich, Y; Kirchner, B; Notbohm, M; Schiekirka, S; Simmenroth, A; Raupach, T

    2018-02-01

    Recent studies in undergraduate medical education have demonstrated the advantage of repeated testing over repeated practice with regard to knowledge and skills retention. The aim of this study was to investigate whether this "testing effect" also applies to skills retention in undergraduate dental education. In this prospective, randomised controlled trial, fourth-year dental students at Göttingen University Medical Centre participated in a training session on surgical suturing in winter term 2014/2015. Following this, they were either assigned to two sessions of additional skills training (group A) or two sessions of skills assessment with feedback (group B). These sessions were spaced over a period of 4 weeks. Skills retention was assessed in a summative objective structured clinical examination (OSCE) at the end of term, that is 6 months after the initial teaching session. A total of 32 students completed the study. With regard to suturing, OSCE performance was significantly better in group B than group A (81.9±13.1% vs 63.0±15.4%; P=0.001; Cohen's d=1.33). There was no significant OSCE performance difference in the two groups with regard to other learning objectives that were addressed in the end-of-term examination. Thus, the group difference was specific to suturing skills. This is the first study to demonstrate that in dental education, repeated testing produces more favourable skills retention than repeated practice. Test-enhanced learning might be a viable concept for skills retention in undergraduate dentistry education. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Oral repeated-dose systemic and reproductive toxicity of 6:2 fluorotelomer alcohol in mice

    Directory of Open Access Journals (Sweden)

    Pushkor Mukerji

    2015-01-01

    Full Text Available 6:2 fluorotelomer alcohol (6:2 FTOH was evaluated for potential systemic repeated-dose and reproductive toxicity in mice. 6:2 FTOH was administered by oral gavage to CD-1 mice as a suspension in 0.5% aqueous methylcellulose with 0.1% Tween-80 at dosages of 1, 5, 25, or 100 mg/kg/day. The no-observed-adverse-effect level (NOAEL for systemic toxicity was 25 mg/kg/day (males and 5 mg/kg/day (females, based on effects at higher doses on mortality, clinical observations, body weight, nutritional parameters, hematology (red and white blood cell, clinical chemistry (liver-related, liver weights, and histopathology (liver, teeth, reproductive tract, and mammary gland. However, 6:2 FTOH was not a selective reproductive toxicant. The NOAEL for reproductive toxicity was >100 mg/kg/day; no effects on reproductive outcome were observed at any dosage. The NOAEL for viability and growth of the offspring was 25 mg/kg/day, based on clinical signs of delayed maturation in pups, and reductions in pup survival and pup body weight during lactation at 100 mg/kg/day. While the severity of the effects was generally greater in mice than previously reported in CD rats, the overall NOAELs were identical in both species, 5 mg/kg/day for systemic toxicity and 25 mg/kg/day for offspring viability/growth. 6:2 FTOH was not a selective reproductive toxicant in either species; no effects on reproductive outcome occurred at any dose level, and any effects observed in offspring occurred at dose levels that induced mortality and severe toxicity in maternal animals.

  5. Mollusc reproductive toxicity tests - Development and validation of test guidelines

    DEFF Research Database (Denmark)

    Ducrot, Virginie; Holbech, Henrik; Kinnberg, Karin Lund

    . Draft standard operating procedures (SOPs) have been designed based upon literature and expert knowledge from project partners. Pre-validation studies have been implemented to validate the proposed test conditions and identify issues in performing the SOPs and analyzing test results. Pre-validation work......The Organisation for Economic Cooperation and Development is promoting the development and validation of mollusc toxicity tests within its test guidelines programme, eventually aiming for the standardization of mollusc apical toxicity tests. Through collaborative work between academia, industry...... and stakeholders, this study aims to develop innovative partial life-cycle tests on the reproduction of the freshwater gastropods Potamopyrgus antipodarum and Lymnaea stagnalis, which are relevant candidate species for the standardization of mollusc apical toxicity tests assessing reprotoxic effects of chemicals...

  6. Estimation of toxicity using the Toxicity Estimation Software Tool (TEST)

    Science.gov (United States)

    Tens of thousands of chemicals are currently in commerce, and hundreds more are introduced every year. Since experimental measurements of toxicity are extremely time consuming and expensive, it is imperative that alternative methods to estimate toxicity are developed.

  7. A 4-Week Repeated-Dose Oral Toxicity Study of Bojungikgi-Tang in Crl:CD Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    Sae-Rom Yoo

    2017-01-01

    Full Text Available Traditional herbal medicines have been used for centuries in Asian countries. However, recent studies have led to increasing concerns about the safety and toxicity of herbal prescriptions. Bojungikgi-tang (BJIGT, a herbal decoction, has been used in Korea to improve physical strength. To establish the safety information, BJIGT water extract was evaluated in a 4-week repeated-dose oral toxicity test in Crl:CD Sprague Dawley rats. BJIGT was orally administered in daily doses of 0, 500, 1000, and 2000 mg/kg/day for 4 weeks via oral gavage in male and female rats. We examined the mortality, clinical signs, body weight change, food intake, organ weights, hematology, serum biochemistry, and urinalysis parameters. No significant changes were observed in mortality, clinical sings, body weight, food intake, organ weights, hematology, serum biochemistry, and urinalysis parameters between the control group and the BJIGT-treated groups in the rats of both sexes. The results indicate that BJIGT did not induce toxic effects at a dose level up to 2000 mg/kg in rats. Thus, this concentration is considered the nonobservable effect dose in rats and is appropriate for a 13-week subchronic toxicity study.

  8. Test systems to identify reproductive toxicants.

    Science.gov (United States)

    Riecke, K; Stahlmann, R

    2000-09-01

    Experience with drugs and other xenobiotics indicates that both animal testing and epidemiological studies are necessary to provide adequate data for an estimation of risks that might be associated with exposure to a chemical substance. In this review, the pros and cons of test systems for reproductive toxicity are discussed. Usually, several studies are performed to cover the different phases of the reproductive cycle. In the preclinical development of drugs, the three so-called 'segment testing protocols' have been used for several decades now. More recently, new testing concepts have been accepted internationally which include more flexibility in implementation. Several examples of compounds with the potential for reproductive toxicity are presented in more detail in a discussion of some pitfalls of the tests for fertility (phthalates and fluoroquinolones), teratogenicity (acyclovir and protease inhibitors) and postnatal developmental toxicity (fluoroquinolones). In addition, important aspects of kinetics and metabolism as a prerequisite for a rational interpretation of results from toxicological studies are briefly discussed. In vitro assays are useful for supplementing the routinely used in vivo approaches or for studying an expected or defined effect, but they are not suitable for revealing an unknown effect of a chemical on the complex reproductive process.

  9. Development of QSAR models using artificial neural network analysis for risk assessment of repeated-dose, reproductive, and developmental toxicities of cosmetic ingredients.

    Science.gov (United States)

    Hisaki, Tomoka; Aiba Née Kaneko, Maki; Yamaguchi, Masahiko; Sasa, Hitoshi; Kouzuki, Hirokazu

    2015-04-01

    Use of laboratory animals for systemic toxicity testing is subject to strong ethical and regulatory constraints, but few alternatives are yet available. One possible approach to predict systemic toxicity of chemicals in the absence of experimental data is quantitative structure-activity relationship (QSAR) analysis. Here, we present QSAR models for prediction of maximum "no observed effect level" (NOEL) for repeated-dose, developmental and reproductive toxicities. NOEL values of 421 chemicals for repeated-dose toxicity, 315 for reproductive toxicity, and 156 for developmental toxicity were collected from Japan Existing Chemical Data Base (JECDB). Descriptors to predict toxicity were selected based on molecular orbital (MO) calculations, and QSAR models employing multiple independent descriptors as the input layer of an artificial neural network (ANN) were constructed to predict NOEL values. Robustness of the models was indicated by the root-mean-square (RMS) errors after 10-fold cross-validation (0.529 for repeated-dose, 0.508 for reproductive, and 0.558 for developmental toxicity). Evaluation of the models in terms of the percentages of predicted NOELs falling within factors of 2, 5 and 10 of the in-vivo-determined NOELs suggested that the model is applicable to both general chemicals and the subset of chemicals listed in International Nomenclature of Cosmetic Ingredients (INCI). Our results indicate that ANN models using in silico parameters have useful predictive performance, and should contribute to integrated risk assessment of systemic toxicity using a weight-of-evidence approach. Availability of predicted NOELs will allow calculation of the margin of safety, as recommended by the Scientific Committee on Consumer Safety (SCCS).

  10. Predictive acute toxicity tests with pesticides.

    Science.gov (United States)

    Brown, V K

    1983-01-01

    By definition pesticides are biocidal products and this implies a probability that pesticides may be acutely toxic to species other than the designated target species. The ways in which pesticides are manufactured, formulated, packaged, distributed and used necessitates a potential for the exposure of non-target species although the technology exists to minimize adventitious exposure. The occurrence of deliberate exposure of non-target species due to the misuse of pesticides is known to happen. The array of predictive acute toxicity tests carried out on pesticides and involving the use of laboratory animals can be justified as providing data on which hazard assessment can be based. This paper addresses the justification and rationale of this statement.

  11. Microfluidics for Antibiotic Susceptibility and Toxicity Testing

    Directory of Open Access Journals (Sweden)

    Jing Dai

    2016-10-01

    Full Text Available The recent emergence of antimicrobial resistance has become a major concern for worldwide policy makers as very few new antibiotics have been developed in the last twenty-five years. To prevent the death of millions of people worldwide, there is an urgent need for a cheap, fast and accurate set of tools and techniques that can help to discover and develop new antimicrobial drugs. In the past decade, microfluidic platforms have emerged as potential systems for conducting pharmacological studies. Recent studies have demonstrated that microfluidic platforms can perform rapid antibiotic susceptibility tests to evaluate antimicrobial drugs’ efficacy. In addition, the development of cell-on-a-chip and organ-on-a-chip platforms have enabled the early drug testing, providing more accurate insights into conventional cell cultures on the drug pharmacokinetics and toxicity, at the early and cheaper stage of drug development, i.e., prior to animal and human testing. In this review, we focus on the recent developments of microfluidic platforms for rapid antibiotics susceptibility testing, investigating bacterial persistence and non-growing but metabolically active (NGMA bacteria, evaluating antibiotic effectiveness on biofilms and combinatorial effect of antibiotics, as well as microfluidic platforms that can be used for in vitro antibiotic toxicity testing.

  12. The rise in carboxyhemoglobin from repeated pulmonary diffusing capacity tests.

    Science.gov (United States)

    Zavorsky, Gerald S

    2013-03-01

    The purpose of this study determined the rise in carboxyhemoglobin percentage (COHb) from repeated pulmonary diffusing capacity tests using 5 or 10s single breath-hold maneuvers. Five male and four female non-smokers [baseline COHb=1.2 (SD 0.5%)] performed repeated pulmonary diffusing capacity testing on two separate days. The days were randomized to either repeated 10s (0.28% CO), or 5s (0.28% CO, 55ppm NO) breath-hold maneuvers. Twenty-two 5s breath-hold maneuvers, each separated by 4min rest, raised COHb to 11.1 (1.4)% and minimally raised the methemoglobin percentage (METHb) by 0.3 (0.2)% to a value of 0.8 (0.2)%. After the 22nd test, pulmonary diffusing capacity for carbon monoxide (DLCO) was reduced by about 4mL/min/mmHg, equating to a 0.44% increase in COHb per 5s breath-hold maneuver and a concomitant 0.35mL/min/mmHg decrease in DLCO. Pulmonary diffusing capacity for nitric oxide (DLNO) was not altered after 22 tests. On another day, the 10s single breath-hold maneuver increased COHb by 0.64% per test, and reduced DLCO by 0.44mL/min/mmHg per test. In conclusion, 5s breath-hold maneuvers do not appreciably raise METHb or DLNO, and DLCO is only significantly reduced when COHb is at least 6%. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Toxicity of Uranium Adsorbent Materials using the Microtox Toxicity Test

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jiyeon [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jeters, Robert T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, Gary A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bonheyo, George T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-01

    The Marine Sciences Laboratory at the Pacific Northwest National Laboratory evaluated the toxicity of a diverse range of natural and synthetic materials used to extract uranium from seawater. The uranium adsorbent materials are being developed as part of the U. S. Department of Energy, Office of Nuclear Energy, Fuel Resources Program. The goal of this effort was to identify whether deployment of a farm of these materials into the marine environment would have any toxic effects on marine organisms.

  14. Screening of repeated dose toxicity data present in SCC(NF)P/SCCS safety evaluations of cosmetic ingredients.

    Science.gov (United States)

    Vinken, Mathieu; Pauwels, Marleen; Ates, Gamze; Vivier, Manon; Vanhaecke, Tamara; Rogiers, Vera

    2012-03-01

    Alternative methods, replacing animal testing, are urgently needed in view of the European regulatory changes in the field of cosmetic products and their ingredients. In this context, a joint research initiative called SEURAT was recently raised by the European Commission and COLIPA, representing the European cosmetics industry, with the overall goal of developing an animal-free repeated dose toxicity testing strategy for human safety assessment purposes. Although cosmetic ingredients are usually harmless for the consumer, one of the initial tasks of this research consortium included the identification of organs that could potentially be affected by cosmetic ingredients upon systemic exposure. The strategy that was followed hereof is described in the present paper and relies on the systematic evaluation, by using a self-generated electronic databank, of published reports issued by the scientific committee of DG SANCO responsible for the safety of cosmetic ingredients. By screening of the repeated dose toxicity studies present in these reports, it was found that the liver is potentially the most frequently targeted organ by cosmetic ingredients when orally administered to experimental animals, followed by the kidney and the spleen. Combined listing of altered morphological, histopathological, and biochemical parameters subsequently indicated the possible occurrence of hepatotoxicity, including steatosis and cholestasis, triggered by a limited number of cosmetic compounds. These findings are not only of relevance for the in vitro modeling efforts and choice of compounds to be tested in the SEURAT project cluster, but also demonstrate the importance of using previously generated toxicological data through an electronic databank for addressing specific questions regarding the safety evaluation of cosmetic ingredients.

  15. Repeatability and responsiveness of exercise tests in pulmonary arterial hypertension.

    Science.gov (United States)

    Mainguy, Vincent; Malenfant, Simon; Neyron, Anne-Sophie; Bonnet, Sébastien; Maltais, François; Saey, Didier; Provencher, Steeve

    2013-08-01

    Exercise tolerance in pulmonary arterial hypertension (PAH) is most commonly assessed by the 6-min walk test (6MWT). Whether endurance exercise tests are more responsive than the 6MWT remains unknown. 20 stable PAH patients (mean±sd age 53±15 years and mean pulmonary arterial pressure 44±16 mmHg) already on PAH monotherapy completed the 6MWT, the endurance shuttle walk test (ESWT) and the cycle endurance test (CET) before and after the addition of sildenafil citrate 20 mg three times daily or placebo for 28 days in a randomised double-blind crossover setting. Pre- or post-placebo tests were used to assess repeatability of each exercise test, whereas pre- or post-sildenafil citrate tests were used to assess their responsiveness. Sildenafil citrate led to placebo-corrected changes in exercise capacity of 18±25 m (p = 0.02), 58±235 s (p = 0.58) and 29±77 s (p = 0.09) for the 6MWT, the ESWT and the CET, respectively. The 6MWT was associated with a lower coefficient of variation between repeated measures (3% versus 18% versus 13%), resulting in a higher standardised response mean compared with endurance tests (0.72, 0.25 and 0.38 for the 6MWT, the ESWT and the CET, respectively). The 6MWT had the best ability to capture changes in exercise capacity when sildenafil citrate was combined with patients' baseline monotherapy, supporting its use as an outcome measure in PAH.

  16. Repeated exposure to iron oxide nanoparticles causes testicular toxicity in mice.

    Science.gov (United States)

    Sundarraj, Kiruthika; Manickam, Vijayprakash; Raghunath, Azhwar; Periyasamy, Madhivadhani; Viswanathan, Mangala Priya; Perumal, Ekambaram

    2017-02-01

    The aim of this study was to determine whether repeated exposure to iron oxide nanoparticles (Fe 2 O 3 -NPs) could be toxic to mice testis. Fe 2 O 3 -NPs (25 and 50 mg/kg) were intraperitoneally administered into mice once a week for 4 weeks. Our study showed that Fe 2 O 3 -NPs have the ability to cross the blood-testis barrier to get into the testis. The findings showed that exposure resulted in the accumulation of Fe 2 O 3 -NPs which was evidenced from the iron content and accumulation in the testis. Furthermore, 25 and 50 mg/kg Fe 2 O 3 -NPs administration increased the reactive oxygen species, lipid peroxidation, protein carbonyl content, glutathione peroxidase activity, and nitric oxide levels with a concomitant decrease in the levels of antioxidants-superoxide dismutase, catalase, glutathione, and vitamin C. Increased expression of Bax, cleaved-caspase-3, and cleaved-PARP confirms apoptosis. Serum testosterone levels increased with increased concentration of Fe 2 O 3 -NPs exposure. In addition, the histopathological lesions like vacuolization, detachment, and sloughing of germ cells were also observed in response to Fe 2 O 3 -NPs treatment. The data from our study entailed that testicular toxicity caused by Fe 2 O 3 -NPs exposure may be associated with Fe 2 O 3 -NPs accumulation leading to oxidative stress and apoptosis. Therefore, precautions should be taken in the safe use of Fe 2 O 3 -NPs to avoid complications in the fertility of males. Further research will unravel the possible molecular mechanisms on testicular toxicity of Fe 2 O 3 -NPs. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 594-608, 2017. © 2016 Wiley Periodicals, Inc.

  17. TEST (Toxicity Estimation Software Tool) Ver 4.1

    Science.gov (United States)

    The Toxicity Estimation Software Tool (T.E.S.T.) has been developed to allow users to easily estimate toxicity and physical properties using a variety of QSAR methodologies. T.E.S.T allows a user to estimate toxicity without requiring any external programs. Users can input a chem...

  18. 30 CFR 250.522 - When do I have to repeat casing diagnostic testing?

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to repeat casing diagnostic... Operations Casing Pressure Management § 250.522 When do I have to repeat casing diagnostic testing? Casing diagnostic testing must be repeated according to the following table: When * * * you must repeat diagnostic...

  19. Impact of repeated exposure on toxicity of perchloroethylene in Swiss Webster mice

    International Nuclear Information System (INIS)

    Philip, Binu K.; Mumtaz, Moiz M.; Latendresse, John R.; Mehendale, Harihara M.

    2007-01-01

    The aim was to study the subchronic toxicity of perchloroethylene (Perc) by measuring injury and repair in liver and kidney in relation to disposition of Perc and its major metabolites. Male SW mice (25-29 g) were given three dose levels of Perc (150, 500, and 1000 mg/kg day) via aqueous gavage for 30 days. Tissue injury was measured during the dosing regimen (0, 1, 7, 14, and 30 days) and over a time course of 24-96 h after the last dose (30 days). Perc produced significant liver injury (ALT) after single day exposure to all three doses. Liver injury was mild to moderate and regressed following repeated exposure for 30 days. Subchronic Perc exposure induced neither kidney injury nor dysfunction during the entire time course as evidenced by normal renal histology and BUN. TCA was the major metabolite detected in blood, liver, and kidney. Traces of DCA were also detected in blood at initial time points after single day exposure. With single day exposure, metabolism of Perc to TCA was saturated with all three doses. AUC/dose ratio for TCA was significantly decreased with a concomitant increase in AUC/dose of Perc levels in liver and kidney after 30 days as compared to 1 day exposures, indicating inhibition of metabolism upon repeated exposure to Perc. Hepatic CYP2E1 expression and activity were unchanged indicating that CYP2E1 is not the critical enzyme inhibited. Hepatic CYP4A expression, measured as a marker of peroxisome proliferation was increased transiently only on day 7 with the high dose, but was unchanged at later time points. Liver tissue repair peaked at 7 days, with all three doses and was sustained after medium and high dose exposure for 14 days. These data indicate that subchronic Perc exposure via aqueous gavage does not induce nephrotoxicity and sustained hepatotoxicity suggesting adaptive hepatic repair mechanisms. Enzymes other than CYP2E1, involved in the metabolism of Perc may play a critical role in the metabolism of Perc upon subchronic exposure

  20. Repeat Chlamydia trachomatis testing among heterosexual STI outpatient clinic visitors in the Netherlands: a longitudinal study.

    Science.gov (United States)

    Visser, Maartje; van Aar, Fleur; Koedijk, Femke D H; Kampman, Carolina J G; Heijne, Janneke C M

    2017-12-20

    Chlamydia infections are common in both men and women, are often asymptomatic and can cause serious complications. Repeat testing in high-risk groups is therefore indicated. In the Netherlands, guidelines on repeat chlamydia testing differ between testing facilities, and knowledge on repeat testing behaviour is limited. Here, we analyse the current repeat testing behaviour of heterosexual STI clinic visitors, and aim to identify groups for which repeat testing advice could be advantageous. Longitudinal surveillance data from all Dutch STI outpatient clinics were used, which included all STI clinic consultations carried out among heterosexual men and women between June 2014 and December 2015. Repeat testing was defined as returning to the same STI clinic between 35 days and 12 months after initial consultation. We calculated chlamydia positivity at repeat test stratified by initial test result and time between consultations. Logistic regression analyses were used to identify predictors of repeat testing, and predictors of having a chlamydia positive repeat test. In total, 140,486 consultations in 75,487 women and 46,286 men were available for analyses. Overall, 15.4% of women and 11.1% of men returned to the STI clinic within the study period. Highest chlamydia positivity at repeat test was seen 3-5 months after initial positive test. Among both women and men, repeat testing was associated with non-Western ethnicity, having had more than two sex partners in the past 6 months, reporting STI symptoms, having a history of STI, and having a chlamydia positive initial test. Among repeat testers, chlamydia positive repeat test was most strongly associated with younger age, followed by a chlamydia positive initial test. Repeat testing most often resulted in a positive test result among young heterosexuals (<25) and heterosexuals of any age with a chlamydia infection at the initial consultation. Further efforts are needed to determine optimal repeat testing strategies.

  1. 78 FR 66700 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2013-11-06

    ... additive for food Rat--Up-and-Down processing, and as Procedure. ingredient in aluminum Micronucleus Test... Toxicity to Fish; Acute Toxicity to Daphnia; Toxicity to Algae; Acute Toxicity to Mammals; Bacterial..., cold Study in Zebra Fish set, and sheet-fed (Brachydanio rerio). applications. Acute Toxicity Study in...

  2. Single, 14-Day, and 13-Week Repeated Dose Toxicity Studies of Daily Oral Gelidium elegans Extract Administration to Rats.

    Science.gov (United States)

    Choi, Jia; Ryu, Su-Jung; Kim, Kui-Jin; Kim, Hyung-Min; Chung, Hee-Chul; Lee, Boo-Yong

    2018-01-20

    Gelidium elegans extract (GEE) is derived from a red alga from the Asia-Pacific region, which has antioxidant, anti-adipogenic, and anti-hyperglycemic effects. However, detailed studies of the toxicology of GEE have not been performed. We evaluated the single oral dose toxicity of GEE in male and female Sprague-Dawley (CD) rats. GEE did not cause deaths or have toxic effects at dosages of 5000 mg/kg/day, although compound-colored stools and diarrhea were observed in both sexes, which lasted 5000 mg/kg. We next evaluated the repeated oral dose toxicity of GEE in CD rats over 14 days and 13 weeks. GEE did not induce any significant toxicological changes in either sex at 2000 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects, in terms of clinical signs, mortality, body mass, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy, organ masses, or histopathology, at dosages of 500, 1000, or 2000 mg/kg/day. The no observed adverse effect level (NOAEL) for GEE is thus likely to be >2000 mg/kg/day, and no pathology was identified in potential target organs. Therefore, this study indicates that repeated oral dosing with GEE is safe in CD rats.

  3. Single, 14-Day, and 13-Week Repeated Dose Toxicity Studies of Daily Oral Gelidium elegans Extract Administration to Rats

    Directory of Open Access Journals (Sweden)

    Jia Choi

    2018-01-01

    Full Text Available Gelidium elegans extract (GEE is derived from a red alga from the Asia–Pacific region, which has antioxidant, anti-adipogenic, and anti-hyperglycemic effects. However, detailed studies of the toxicology of GEE have not been performed. We evaluated the single oral dose toxicity of GEE in male and female Sprague-Dawley (CD rats. GEE did not cause deaths or have toxic effects at dosages of 5000 mg/kg/day, although compound-colored stools and diarrhea were observed in both sexes, which lasted <2 days. Therefore, the LD50 of GEE is likely to be >5000 mg/kg. We next evaluated the repeated oral dose toxicity of GEE in CD rats over 14 days and 13 weeks. GEE did not induce any significant toxicological changes in either sex at 2000 mg/kg/day. Repeated oral dose toxicity studies showed no adverse effects, in terms of clinical signs, mortality, body mass, food consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy, organ masses, or histopathology, at dosages of 500, 1000, or 2000 mg/kg/day. The no observed adverse effect level (NOAEL for GEE is thus likely to be >2000 mg/kg/day, and no pathology was identified in potential target organs. Therefore, this study indicates that repeated oral dosing with GEE is safe in CD rats.

  4. Unraveling the Role of RNA Mediated Toxicity of C9orf72 Repeats in C9-FTD/ALS

    Directory of Open Access Journals (Sweden)

    Vijay Kumar

    2017-12-01

    Full Text Available The most frequent genetic cause of amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD is intronic hexanucleotide (G4C2 repeat expansions (HRE in the C9orf72 gene. The non-exclusive pathogenic mechanisms by which C9orf72 repeat expansions contribute to these neurological disorders include loss of C9orf72 function and gain-of-function determined by toxic RNA molecules and dipeptides repeats protein toxicity. The expanded repeats are transcribed bidirectionally and forms RNA foci in the central nervous system, and sequester key RNA-binding proteins (RBPs leading to impairment in RNA processing events. Many studies report widespread transcriptome changes in ALS carrying a C9orf72 repeat expansion. Here we review the contribution of RNA foci interaction with RBPs as well as transcriptome changes involved in the pathogenesis of C9orf72- associated FTD/ALS. These informations are essential to elucidate the pathology and therapeutic intervention of ALS and/or FTD.

  5. Simple test guidelines for screening oilspill sorbents for toxicity

    International Nuclear Information System (INIS)

    Blenkinsopp, S.A.; Sergy, G.; Doe, K.; Jackman, P.; Huybers, A.

    1998-01-01

    Environment Canada's Emergencies Science Division has established a program to develop a standard test method suitable for evaluating the toxicity of common sorbent materials. Sorbents are used to absorb or adsorb spilled oil and other hazardous materials. They vary widely in composition and packaging. They are often treated with oleophilic and hydrophobic compounds to improve performance and have been used in large quantities during oil spills. Until now, their potential toxicity has never been considered. Three tests have been evaluated to determine how appropriate they are in screening the toxicity of sorbents. Seven toxicity test recommendations for sorbents were presented. 7 refs., 3 tabs., 2 figs

  6. In Vitro Toxicity testing in the 21st Century

    Directory of Open Access Journals (Sweden)

    Erwin L Roggen

    2011-02-01

    Full Text Available The National Research Council (NRC article Toxicity Testing in the 21st Century: A vision and A Strategy (National Research Council, 2007 was written to bring attention to the application of scientific advances for use in toxicity tests so that chemicals can be tested in a more time and cost efficient manner while providing a more relevant and mechanistic insight into the toxic potential of a compound.Development of tools for in vitro toxicity testing constitutes an important activity of this vision and contributes to the provision of test systems as well as data that are essential for the development of computer modelling tools for e.g. system biology, physiologically-based modelling. This article intends to highlight some of the issues that have to be addressed in order to make in vitro toxicity testing a reality in the 21st century.

  7. A chronic toxicity test protocol using Caridina nilotica (Decapoda ...

    African Journals Online (AJOL)

    Salinization of freshwater resources is an increasing global problem, yet there is a paucity of chronic salinity tolerance data linked to very few chronic toxicity test protocols. This research aimed to generate a chronic toxicity test protocol and protective salinity tolerance data for the indigenous South African freshwater shrimp ...

  8. Mixture toxicity of wood preservative products in the fish embryo toxicity test.

    Science.gov (United States)

    Coors, Anja; Dobrick, Jan; Möder, Monika; Kehrer, Anja

    2012-06-01

    Wood preservative products are used globally to protect wood from fungal decay and insects. We investigated the aquatic toxicity of five commercial wood preservative products, the biocidal active substances and some formulation additives contained therein, as well as six generic binary mixtures of the active substances in the fish embryo toxicity test (FET). Median lethal concentrations (LC50) of the single substances, the mixtures, and the products were estimated from concentration-response curves and corrected for concentrations measured in the test medium. The comparison of the experimentally observed mixture toxicity with the toxicity predicted by the concept of concentration addition (CA) showed less than twofold deviation for all binary mixtures of the active substances and for three of the biocidal products. A more than 60-fold underestimation of the toxicity of the fourth product by the CA prediction was detected and could be explained fully by the toxicity of one formulation additive, which had been labeled as a hazardous substance. The reason for the 4.6-fold underestimation of toxicity of the fifth product could not be explained unambiguously. Overall, the FET was found to be a suitable screening tool to verify whether the toxicity of formulated wood preservatives can reliably be predicted by CA. Applied as a quick and simple nonanimal screening test, the FET may support approaches of applying component-based mixture toxicity predictions within the environmental risk assessment of biocidal products, which is required according to European regulations. Copyright © 2012 SETAC.

  9. Immunotoxicity, genotoxicity and epigenetic toxicity of nanomaterials: New strategies for toxicity testing?

    Science.gov (United States)

    Dusinska, Maria; Tulinska, Jana; El Yamani, Naouale; Kuricova, Miroslava; Liskova, Aurelia; Rollerova, Eva; Rundén-Pran, Elise; Smolkova, Bozena

    2017-11-01

    The unique properties of nanomaterials (NMs) are beneficial in numerous industrial and medical applications. However, they could also induce unintended effects. Thus, a proper strategy for toxicity testing is essential in human hazard and risk assessment. Toxicity can be tested in vivo and in vitro; in compliance with the 3Rs, alternative strategies for in vitro testing should be further developed for NMs. Robust, standardized methods are of great importance in nanotoxicology, with comprehensive material characterization and uptake as an integral part of the testing strategy. Oxidative stress has been shown to be an underlying mechanism of possible toxicity of NMs, causing both immunotoxicity and genotoxicity. For testing NMs in vitro, a battery of tests should be performed on cells of human origin, either cell lines or primary cells, in conditions as close as possible to an in vivo situation. Novel toxicity pathways, particularly epigenetic modification, should be assessed along with conventional toxicity testing methods. However, to initiate epigenetic toxicity screens for NM exposure, there is a need to better understand their adverse effects on the epigenome, to identify robust and reproducible causal links between exposure, epigenetic changes and adverse phenotypic endpoints, and to develop improved assays to monitor epigenetic toxicity. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Irritancy ranking of anionic detergents using one-time occlusive, repeated occlusive and repeated open tests

    NARCIS (Netherlands)

    Tupker, RA; Bunte, EE; Fidler, [No Value; Wiechers, JW; Coenraads, PJ

    Discrepancies between the one-time patch test and the wash test regarding the ranking of irritancy of detergents have been found in the literature. The aim of the present study was to investigate the concordance of irritancy rank order of 4 anionic detergents tested by 3 different exposure methods,

  11. Zinc oxide nanoparticles: a 90-day repeated-dose dermal toxicity study in rats

    Directory of Open Access Journals (Sweden)

    Ryu HJ

    2014-12-01

    Full Text Available Hwa Jung Ryu,1,* Mu Yeb Seo,2,* Sung Kyu Jung,1 Eun Ho Maeng,2 Seung-Young Lee,2 Dong-Hyouk Jang,2 Taek-Jin Lee,2 Ki-Yeon Jo,2 Yu-Ri Kim,3 Kyu-Bong Cho,4 Meyoung-Kon Kim,3 Beom Jun Lee,5 Sang Wook Son1 1Department of Dermatology, Korea University College of Medicine, Seoul, 2Korea Testing and Research Institute, Gyunggido, 3Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, 4Department of Clinical Laboratory Science, Shinheung College, Uijeongbu, 5College of Veterinary Medicine, Chungbuk National University, Cheongju, Republic of Korea *These authors contributed equally to this work and both should be considered first authors Abstract: Zinc oxide (ZnO works as a long-lasting, broad-spectrum physical sunblock, and can prevent skin cancer, sunburn, and photoaging. Nanosized ZnO particles are used often in sunscreens due to consumer preference over larger sizes, which appear opaque when dermally applied. Although the US Food and Drug Administration approved the use of nanoparticles (NPs in sunscreens in 1999, there are ongoing safety concerns. The aim of this study was to evaluate the subchronic toxicity of ZnO NPs after dermal application according to the Organization for Economic Cooperation and Development Test Guidelines 411 using Good Laboratory Practice. Sprague Dawley rats were randomly divided into eight (one control, one vehicle control, three experimental, and three recovery groups. Different concentrations of ZnO NPs were dermally applied to the rats in the experimental groups for 90 days. Clinical observations as well as weight and food consumption were measured and recorded daily. Hematology and biochemistry parameters were determined. Gross pathologic and histopathologic examinations were performed on selected tissues from all animals. Analyses of tissue were undertaken to determine target organ tissue distribution. There was no increased mortality in the experimental group. Although there

  12. Microcomputer-based tests for repeated-measures: Metric properties and predictive validities

    Science.gov (United States)

    Kennedy, Robert S.; Baltzley, Dennis R.; Dunlap, William P.; Wilkes, Robert L.; Kuntz, Lois-Ann

    1989-01-01

    A menu of psychomotor and mental acuity tests were refined. Field applications of such a battery are, for example, a study of the effects of toxic agents or exotic environments on performance readiness, or the determination of fitness for duty. The key requirement of these tasks is that they be suitable for repeated-measures applications, and so questions of stability and reliability are a continuing, central focus of this work. After the initial (practice) session, seven replications of 14 microcomputer-based performance tests (32 measures) were completed by 37 subjects. Each test in the battery had previously been shown to stabilize in less than five 90-second administrations and to possess retest reliabilities greater than r = 0.707 for three minutes of testing. However, all the tests had never been administered together as a battery and they had never been self-administered. In order to provide predictive validity for intelligence measurement, the Wechsler Adult Intelligence Scale-Revised and the Wonderlic Personnel Test were obtained on the same subjects.

  13. Repeated-dose toxicological studies of Tithonia diversifolia (Hemsl.) A. gray and identification of the toxic compounds.

    Science.gov (United States)

    Passoni, Flávia Donaire; Oliveira, Rejane Barbosa; Chagas-Paula, Daniela Aparecida; Gobbo-Neto, Leonardo; Da Costa, Fernando Batista

    2013-05-20

    Tithonia diversifolia (Hemsl.) A. Gray has been commonly used in folk medicine to treat abscesses, microbiological infections, snake bites, malaria and diabetes. Both anti-inflammatory and anti-malarial properties have been identified using appropriate assays, but the effective doses have demonstrated toxic effects for the experimental animals. Most of the pharmacological activities have been attributed to sesquiterpene lactones (STLs) and some chlorogenic acid derivatives (CAs) in the leaves of this species. This work aimed to evaluate the repeated-dose toxicity of an aqueous extract (AE) from Tithonia diversifolia leaves and to compare the results with an extract rich in STLs (LRE) and a polar extract (PE) without STLs but rich in CAs. The purpose of this work was to provide insights into the identity of the compounds responsible for the toxic effects of Tithonia diversifolia. The major classes of compounds were confirmed in each extract by IR spectra and HPLC-UV-DAD profiling using previously isolated or standard compounds. The toxicity of each extract was evaluated in a repeated-dose toxicity study in Wistar rats for 90 days. The AE is composed of both STLs and CAs, the LRE is rich in STLs, and the PE is rich in CAs. The AE caused alterations in haematological parameters but few alterations in biochemical parameters and was relatively safe at doses lower than 100mg/kg. However, the PE and LRE demonstrated several adverse effects by damaging the liver and kidneys, respectively. STLs and CAs can be toxic in prolonged use at higher doses in extracts prepared from Tithonia diversifolia by affecting the kidneys and liver. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Cholesterol reduction and lack of genotoxic or toxic effects in mice after repeated 21-day oral intake of lemongrass (Cymbopogon citratus) essential oil.

    Science.gov (United States)

    Costa, Celso A R A; Bidinotto, Lucas T; Takahira, Regina K; Salvadori, Daisy M F; Barbisan, Luís F; Costa, Mirtes

    2011-09-01

    Cymbopogon citratus (lemongrass) is currently used in traditional folk medicine. Although this species presents widespread use, there are no scientific data on its efficacy or safety after repeated treatments. Therefore, this work investigated the toxicity and genotoxicity of this lemongrass's essential oil (EO) in male Swiss mice. The single LD(50) based on a 24h acute oral toxicity study was found to be around 3500 mg/kg. In a repeated-dose 21-day oral toxicity study, mice were randomly assigned to two control groups, saline- or Tween 80 0.01%-treated groups, or one of the three experimental groups receiving lemongrass EO (1, 10 or 100mg/kg). No significant changes in gross pathology, body weight, absolute or relative organ weights, histology (brain, heart, kidneys, liver, lungs, stomach, spleen and urinary bladder), urinalysis or clinical biochemistry were observed in EO-treated mice relative to the control groups. Additionally, blood cholesterol was reduced after EO-treatment at the highest dose tested. Similarly, data from the comet assay in peripheral blood cells showed no genotoxic effect from the EO. In conclusion, our findings verified the safety of lemongrass intake at the doses used in folk medicine and indicated the beneficial effect of reducing the blood cholesterol level. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. The impact of repeat-testing of common chemistry analytes at critical concentrations.

    Science.gov (United States)

    Onyenekwu, Chinelo P; Hudson, Careen L; Zemlin, Annalise E; Erasmus, Rajiv T

    2014-12-01

    Early notification of critical values by the clinical laboratory to the treating physician is a requirement for accreditation and is essential for effective patient management. Many laboratories automatically repeat a critical value before reporting it to prevent possible misdiagnosis. Given today's advanced instrumentation and quality assurance practices, we questioned the validity of this approach. We performed an audit of repeat-testing in our laboratory to assess for significant differences between initial and repeated test results, estimate the delay caused by repeat-testing and to quantify the cost of repeating these assays. A retrospective audit of repeat-tests for sodium, potassium, calcium and magnesium in the first quarter of 2013 at Tygerberg Academic Laboratory was conducted. Data on the initial and repeat-test values and the time that they were performed was extracted from our laboratory information system. The Clinical Laboratory Improvement Amendment criteria for allowable error were employed to assess for significant difference between results. A total of 2308 repeated tests were studied. There was no significant difference in 2291 (99.3%) of the samples. The average delay ranged from 35 min for magnesium to 42 min for sodium and calcium. At least 2.9% of laboratory running costs for the analytes was spent on repeating them. The practice of repeating a critical test result appears unnecessary as it yields similar results, delays notification to the treating clinician and increases laboratory running costs.

  16. Acute oral toxicity test of chemical compounds in silkworms.

    Science.gov (United States)

    Usui, Kimihito; Nishida, Satoshi; Sugita, Takuya; Ueki, Takuro; Matsumoto, Yasuhiko; Okumura, Hidenobu; Sekimizu, Kazuhisa

    2016-02-01

    This study performed an acute oral toxicity test of 59 compounds in silkworms. These compounds are listed in OECD guidelines as standard substances for a cytotoxicity test, and median lethal dose (LD(50)) werecalculated for each compound. Acute oral LD(50) values in mammals are listed in OECD guidelines and acute oral LD(50) values in silkworms were determined in this study. R(2) for the correlation between LD(50) values in mammals and LD(50) values in silkworms was 0.66. In addition, the acute oral toxicity test in silkworms was performed by two different facilities, and test results from the facilities were highly reproducible. These findings suggest that an acute oral toxicity test in silkworms is a useful way to evaluate the toxicity of compounds in mammals.

  17. Repeat HIV testing during pregnancy and delivery: missed opportunities in a rural district hospital in Zambia

    NARCIS (Netherlands)

    Heemelaar, S.; Habets, N.; Makukula, Z.; van Roosmalen, J.; van den Akker, T.

    2015-01-01

    Objective: To assess coverage of repeat HIV testing among women who delivered in a Zambian hospital. HIV testing of pregnant women and repeat testing every 3 months during pregnancy and breastfeeding is the recommended policy in areas of high HIV prevalence. Methods: A prospective implementation

  18. Changes of lead speciation and microbial toxicity in soil treated with repeated Pb exposure in the presence of BDE209.

    Science.gov (United States)

    Zhang, Rong; Zhang, Wei; Liu, Gao; Lin, Kuangfei; Fu, Rongbing

    2016-03-01

    Lead (Pb) and decabromodiphenyl ether (BDE209) are main pollutants at electric waste (e-waste) recycling sites (EWRSs), and their joint toxicological effects have received extensive attention. Frequently, soil pollution at EWRSs usually results from the occurrence of repeated single or multiple pollution events, with continuous impacts on soil microorganisms. Therefore, a laboratory incubation study was conducted to determine Pb bioavailability and microbial toxicity in repeated Pb-polluted soil in the presence of BDE209 for the first time. We evaluated the impacts of repetitive exposure trials on chemical fractions of Pb, and the results showed that repeated single Pb pollution event resulted in an increase of carbonates fraction of Pb, which was different from one-off single Pb exposure. Moreover, one-off Pb-treated groups exhibited higher I R (reduced partition index) values on day 30 and all treatments remained the same I R level at the end of incubation period. The parameters of microbial toxicity were well reflected by soil enzymes. During the entire incubation, the dehydrogenase and urease activities were significantly inhibited by Pb (P soil enzymes were clearly observed (P < 0.05 or 0.01). Such observations would provide useful information for ecological effects of Pb and BDE209 at EWRSs.

  19. Utility of repeat testing of critical values: a Q-probes analysis of 86 clinical laboratories.

    Science.gov (United States)

    Lehman, Christopher M; Howanitz, Peter J; Souers, Rhona; Karcher, Donald S

    2014-06-01

    A common laboratory practice is to repeat critical values before reporting the test results to the clinical care provider. This may be an unnecessary step that delays the reporting of critical test results without adding value to the accuracy of the test result. To determine the proportions of repeated chemistry and hematology critical values that differ significantly from the original value as defined by the participating laboratory, to determine the threshold differences defined by the laboratory as clinically significant, and to determine the additional time required to analyze the repeat test. Participants prospectively reviewed critical test results for 4 laboratory tests: glucose, potassium, white blood cell count, and platelet count. Participants reported the following information: initial and repeated test result; time initial and repeat results were first known to laboratory staff; critical result notification time; if the repeat result was still a critical result; if the repeat result was significantly different from the initial result, as judged by the laboratory professional or policy; significant difference threshold, as defined by the laboratory; the make and model of the instrument used for primary and repeat testing. Routine, repeat analysis of critical values is a common practice. Most laboratories did not formally define a significant difference between repeat results. Repeated results were rarely considered significantly different. Median repeated times were at least 17 to 21 minutes for 10% of laboratories. Twenty percent of laboratories reported at least 1 incident in the last calendar year of delayed result reporting that clinicians indicated had adversely affected patient care. Routine repeat analysis of automated chemistry and hematology critical values is unlikely to be clinically useful and may adversely affect patient care.

  20. Evaluating the Zebrafish Embryo Toxicity Test for Pesticide ...

    Science.gov (United States)

    Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more resource-intensive, juvenile fish acute toxicity tests. However, there is also evidence that fish embryos are less sensitive than juvenile fish for certain types of chemicals, including neurotoxicants. The utility of fish embryos for pesticide hazard assessment was investigated by comparing published zebrafish embryo toxicity data from pesticides with median lethal concentration 50% (LC50) data for juveniles of 3 commonly tested fish species: rainbow trout, bluegill sunfish, and sheepshead minnow. A poor, albeit significant, relationship (r2 = 0.28; p embryo and juvenile fish toxicity when pesticides were considered as a single group, but a much better relationship (r2 = 0.64; p embryo toxicity test endpoints are particularly insensitive to neurotoxicants. These results indicate that it is still premature to replace juvenile fish toxicity tests with embryo-based tests such as the Organisation for Economic Co-op

  1. Biological assays for aquatic toxicity testing

    CSIR Research Space (South Africa)

    Slabbert, JL

    1999-10-01

    Full Text Available and management purposes of effluents. If receiving water is used for drinking water purposes, the Ames Salmonella mutagenicity and toad embryo teratogenicity tests should be included in the battery of tests. Some of the rapid microbiotests, the petrozoan oxygen...

  2. 40 CFR 797.1930 - Mysid shrimp acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... test organisms and eliminating loss of organisms in outflow water. (6) “Static system” means a test..., procedures, and mysids from the same population or culture container, except that none of the chemical is... in chronic toxicity tests should originate from laboratory cultures in order to ensure the...

  3. Organophosphorus insecticides: Toxic effects and bioanalytical tests for evaluating toxicity during degradation processes

    Directory of Open Access Journals (Sweden)

    Čolović Mirjana B.

    2013-01-01

    Full Text Available Organophosphorus insecticides have been the most applied group of insecticides for the last two decades. Their main toxic effects are related to irreversible inactivation of acetylcholinesterase (AChE. Actually, they covalently bind to serine OH group in the enzyme active site forming phosphorylated enzyme that cannot hydrolyze acetylcholine. Organophosphorus insecticides in the environment undergo the natural degradation pathway including mainly homogeneous and heterogeneous hydrolysis (especially at high pH generating non-inhibiting products. Additionally, thio organophosphates are easily oxidized by naturally present oxidants and UV light, forming more toxic and stable oxons. Thus, oxidative degradation procedures, generally referred as advanced oxidation processes (AOP, have been applied for their efficient removal from contaminated waters. The most applied bioassays to monitor the organophosphate toxicity i.e. the detoxification degree during AOP are Vibrio fischeri and AChE bioassays. Vibrio fischeri toxicity test exploits bioluminescence as the measure of luciferase activity of this marine bacterium, whereas AChE bioassay is based on AChE activity inhibition. Both bioanalytical techniques are rapid (several minutes, simple, sensitive and reproducible. Vibrio fischeri test seems to be a versatile indicator of toxic compounds generated in AOP for organophosphorus insecticides degradation. However, detection of neurotoxic AChE inhibitors, which can be formed in AOP of some organophosphates, requires AChE bioassays. Therefore, AChE toxicity test is more appropriate for monitoring the degradation processes of thio organophosphates, because more toxic oxo organophosphates might be formed and overlooked by Vibrio fischeri bioluminescence inhibition. In addition, during organophosphates removal by AOP, compounds with strong genotoxic potential may be formed, which cannot be detected by standard toxicity tests. For this reason, determination of

  4. Implications of Animal Welfare on Toxicity Testing

    DEFF Research Database (Denmark)

    Meyer, Otto A.

    1993-01-01

    The testing strategy for chemical substances is discussed with regard to obtaining improved quality of data for health assessment while respecting the ethical responsibility for consideration of the welfare of the animals involved. Ensuring animal welfare without indulging too much in anthropomor......The testing strategy for chemical substances is discussed with regard to obtaining improved quality of data for health assessment while respecting the ethical responsibility for consideration of the welfare of the animals involved. Ensuring animal welfare without indulging too much...

  5. Evaluation of metals, metalloids, and ash mixture toxicity using sediment toxicity testing.

    Science.gov (United States)

    Stojak, Amber; Bonnevie, Nancy L; Jones, Daniel S

    2015-01-01

    In December 2008, a release of 4.1 million m(3) of coal ash from the Tennessee Valley Authority Kingston Fossil Plant occurred. Ash washed into the Emory River and migrated downstream into the Clinch and Tennessee Rivers. A Baseline Ecological Risk Assessment evaluated risks to ecological receptors from ash in the river system post-dredging. This article describes the approach used and results from sediment toxicity tests, discussing any causal relationships between ash, metals, and toxicity. Literature is limited in the realm of aquatic coal combustion residue (CCR) exposures and the potential magnitude of effects on benthic invertebrates. Sediment samples along a spectrum of ash content were used in a tiered toxicity testing approach and included a combination of 10 day sediment toxicity acute tests and longer-term, partial life cycle "definitive" tests with 2 species (Hyalella azteca and Chironomus dilutus). Arsenic, and to a lesser extent Se, in the ash was the most likely toxicant causing observed effects in the laboratory toxicity tests. Sites in the Emory River with the greatest statistical and biologically significant effects had As concentrations in sediments twice the probable effects concentration of 33 mg/kg. These sites contained greater than 50% ash. Sites with less than approximately 50% ash in sediments exhibited fewer significant toxic responses relative to the reference sediment in the laboratory. The results discussed here present useful evidence of only limited effects occurring from a worst-case exposure pathway. These results provided a valuable line of evidence for the overall assessment of risks to benthic invertebrates and to other ecological receptors, and were crucial to risk management and development of project remediation goals. © 2014 SETAC.

  6. Repeated dose oral toxicity of inorganic mercury in wistar rats: biochemical and morphological alterations

    Directory of Open Access Journals (Sweden)

    M. D. Jegoda

    2013-06-01

    Full Text Available Aim: The study was conducted to find out the possible toxic effect of mercuric chloride (HgCl2 at the histological, biochemical, and haematological levels in the wistar rats for 28 days. Materials and Methods: The biochemical and hematological alteration were estimated in four groups of rat (each group contain ten animals, which were treated with 0 (control, 2, 4, and 8 mg/kg body weight of HgCl2 through oral gavage. At the end of study all rats were sacrificed and subjected for histopathology. Result: A significantly (P < 0.05 higher level of serum alanine amino transferase (ALT, gamma Glutamyle Transferase, and creatinine were recorded in treatment groups, while the level of alkaline phosphtase (ALP was significantly decreased as compared to the control group. The toxic effect on hematoclogical parameter was characterized by significant decrease in hemoglobin, packed cell volume, total erythrocytes count, and total leukocyte count. Gross morphological changes include congestion, severe haemorrhage, necrosis, degenerative changes in kidneys, depletion of lymphocyte in spleen, decrease in concentration of mature spermatocyte, and edema in testis. It was notable that kidney was the most affected organ. Conclusion: Mercuric chloride (HgCl caused dose-dependent toxic effects on blood parameters and kidney. [Vet World 2013; 6(8.000: 563-567

  7. Study on irradiation of freshening ginseng and toxicity test

    International Nuclear Information System (INIS)

    Wang Ziwen; Xu Dechun; Yang Wanqi

    1991-01-01

    The ginsengs irradiated by 1 or 2 kGy of γ-rays have been stored for 6 months under room temperature. Its freshening rates was 86.67% and 88.33% respectively. The saponin content was maintained. The irradiated ginsengs had the vigour of sap fully and beautiful colour. Therefore they can be stored much longer for sell. The toxicity test showed that there was no toxicity for irradiated ginsengs

  8. The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test

    International Nuclear Information System (INIS)

    Davies, N.A.Nicola A.; Hodson, M.E.Mark E.; Black, S.Stuart

    2003-01-01

    Timing of lead addition and worms to soil affects the response of the worms to soil affects the response of the worms to lead. - Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC 50 s for 14 and 28 days were 5311 and 5395 μg Pb g -1 soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 μg Pb g -1 soil . The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 μg g -1 soil accumulated lead at a faster rate (3.16 μg Pb g -1 tissue day -1 ) than those in the 3000 μg g -1 soil (2.21 μg Pb g -1 tissue day -1 ). The third experiment was a timed experiment with worms cultivated in soil containing 7000 μg Pb g -1 soil . Soil and lead nitrate solution were mixed and stored at 20 deg. C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration

  9. Results of repeat tracer tests at Ohaaki, NZ

    International Nuclear Information System (INIS)

    McCabe, W.J.; Morris, C.

    1995-01-01

    During 20 years of tracer testing at Ohaaki a number of wells have been used more than once as tracer injection sites. In studying the various responses obtained it has been necessary to consider variations in the experimental test conditions before making comparisons which relate to field conditions. Some very significant changes have occurred in the field hydrology in recent years and water flow speeds as high as those encountered at Wairakei have been demonstrated. (author). 4 refs., 2 tabs., 10 figs

  10. Metal availability and soil toxicity after repeated croppings of Thlaspi caerulescens in metal contaminated soils

    International Nuclear Information System (INIS)

    Keller, Catherine; Hammer, Daniel

    2004-01-01

    Metal phytoextraction with hyperaccumulating plants could be a useful method to decontaminate soils, but it is not fully validated yet. In order to quantify the efficiency of Cd and Zn extraction from a calcareous soil with and without Fe amendment and an acidic soil, we performed a pot experiment with three successive croppings of Thlaspi caerulescens followed by 3 months without plant and 7 weeks with lettuce. We used a combined approach to assess total extraction efficiency (2 M HNO 3 -extractable metals), changes in metal bio/availability (0.1 M NaNO 3 -extractable metals and lettuce uptake) and toxicity (lettuce biomass and the BIOMETreg] biosensor). The soil solution was monitored over the whole experiment. In the calcareous soil large Cu concentrations were probably responsible for chlorosis symptoms observed on T. caerulescens. When this soil was treated with Fe, the amount of extracted metal by T. caerulescens increased and metal availability and soil toxicity decreased when compared to the untreated soil. In the acidic soil, T. caerulescens was most efficient: Cd and Zn concentrations in plants were in the range of hyperaccumulation and HNO 3 -extractable Cd and Zn, metal bio/availability, soil toxicity, and Cd and Zn concentrations in the soil solution decreased significantly. However, a reduced Cd concentration measured in the third T. caerulescens cropping indicated a decrease in metal availability below a critical threshold, whereas the increase of dissolved Cd and Zn concentrations after the third cropping may be the early sign of soil re-equilibration. This indicates that phytoextraction efficiency must be assessed by different approaches in order not to overlook any potential hazard and that an efficient phytoextraction scheme will have to take into account the different dynamics of the soil-plant system

  11. THE ROLE OF INORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING

    Science.gov (United States)

    Effluent toxicity testing methods have been well defined, but to a large part have not attempted to segregate the effects of active ionic concentrations and ion imbalances upon test and species performances. The role that various total dissolved solids in effluents have on regula...

  12. 40 CFR 797.1950 - Mysid shrimp chronic toxicity test.

    Science.gov (United States)

    2010-07-01

    ... on the chronic toxicity of chemical substances and mixtures (“chemicals”) subject to environmental... with the test design into retention chambers within the test and the control chambers. Mysids in the... and experimental history. Mysids used for establishing laboratory cultures may be purchased...

  13. Consensus report on the future of animal-free systemic toxicity testing.

    Science.gov (United States)

    Leist, Marcel; Hasiwa, Nina; Rovida, Costanza; Daneshian, Mardas; Basketter, David; Kimber, Ian; Clewell, Harvey; Gocht, Tilman; Goldberg, Alan; Busquet, Francois; Rossi, Anna-Maria; Schwarz, Michael; Stephens, Martin; Taalman, Rob; Knudsen, Thomas B; McKim, James; Harris, Georgina; Pamies, David; Hartung, Thomas

    2014-01-01

    Since March 2013, animal use for cosmetics testing for the European market has been banned. This requires a renewed view on risk assessment in this field. However, in other fields as well, traditional animal experimentation does not always satisfy requirements in safety testing, as the need for human-relevant information is ever increasing. A general strategy for animal-free test approaches was outlined by the US National Research Council`s vision document for Toxicity Testing in the 21st Century in 2007. It is now possible to provide a more defined roadmap on how to implement this vision for the four principal areas of systemic toxicity evaluation: repeat dose organ toxicity, carcinogenicity, reproductive toxicity and allergy induction (skin sensitization), as well as for the evaluation of toxicant metabolism (toxicokinetics) (Fig. 1). CAAT-Europe assembled experts from Europe, America and Asia to design a scientific roadmap for future risk assessment approaches and the outcome was then further discussed and refined in two consensus meetings with over 200 stakeholders. The key recommendations include: focusing on improving existing methods rather than favoring de novo design; combining hazard testing with toxicokinetics predictions; developing integrated test strategies; incorporating new high content endpoints to classical assays; evolving test validation procedures; promoting collaboration and data-sharing of different industrial sectors; integrating new disciplines, such as systems biology and high throughput screening; and involving regulators early on in the test development process. A focus on data quality, combined with increased attention to the scientific background of a test method, will be important drivers. Information from each test system should be mapped along adverse outcome pathways. Finally, quantitative information on all factors and key events will be fed into systems biology models that allow a probabilistic risk assessment with flexible

  14. Repeated sub-chronic oral toxicity study of xylooligosaccharides (XOS) in dogs.

    Science.gov (United States)

    Gao, Yonglin; Wang, Yunzhi; Li, Yanshen; Han, Rui; Li, Chunmei; Xiao, Lin; Cho, Susan; Ma, Yukui; Fang, Chao; Lee, Albert W

    2017-06-01

    In this study, Beagle dogs were administered xylooligosaccharide (XOS, CAS # 87099-0) at doses of 0, 1250, 2500, and 5000 mg/kg/day by oral gavage for 26 weeks. A 4-week recovery period was added to observe delayed or reversible toxicity. Measurements included body weight, food consumption, clinical observations, temperature, electrocardiogram (ECG), urinalysis, blood chemistry, hematology, organ weight, gross necropsy, and histopathological examination. Except for transient diarrhea or vomiting, no treatment-related adverse effects were noted. In the mid-dose groups, transitional diarrhea was observed in the initial 1-2 weeks. In the high-dose groups, diarrhea and/or vomiting were observed episodically over the duration of treatment. However, they disappeared after XOS was withdrawn in the recovery period. Although there was a tendency toward less weight gain in the high-dose group animal group, this is typical in animals and humans fed non-digestible carbohydrates. This chronic toxicity study demonstrated that the no observed adverse effect level (NOAEL) of XOS is 2500 mg/kg body weight (BW)/day. Based on body surface area (conversion factor of 0.54 for dogs to human), this corresponds to daily doses of 1350 mg/kg BW or 81-108 g XOS in human adults weighing 60-80 kg. Copyright © 2017. Published by Elsevier Inc.

  15. Toxicity of compounds with endocrine activity in the OECD 421 reproductive toxicity screening test

    NARCIS (Netherlands)

    Piersma AH; Verhoef A; Elvers LH; Wester PW; LEO; LPI

    1998-01-01

    The issue of endocrine disruption has, in view of human risk assessment, raised the question on whether more sensitive test methods are needed to detect the reproductive toxic properties of xenobiotic compounds with endocrine properties. We studied six known and alleged endocrine disruptors in an

  16. Functional toxicology: tools to advance the future of toxicity testing

    Science.gov (United States)

    Gaytán, Brandon D.; Vulpe, Chris D.

    2014-01-01

    The increased presence of chemical contaminants in the environment is an undeniable concern to human health and ecosystems. Historically, by relying heavily upon costly and laborious animal-based toxicity assays, the field of toxicology has often neglected examinations of the cellular and molecular mechanisms of toxicity for the majority of compounds—information that, if available, would strengthen risk assessment analyses. Functional toxicology, where cells or organisms with gene deletions or depleted proteins are used to assess genetic requirements for chemical tolerance, can advance the field of toxicity testing by contributing data regarding chemical mechanisms of toxicity. Functional toxicology can be accomplished using available genetic tools in yeasts, other fungi and bacteria, and eukaryotes of increased complexity, including zebrafish, fruit flies, rodents, and human cell lines. Underscored is the value of using less complex systems such as yeasts to direct further studies in more complex systems such as human cell lines. Functional techniques can yield (1) novel insights into chemical toxicity; (2) pathways and mechanisms deserving of further study; and (3) candidate human toxicant susceptibility or resistance genes. PMID:24847352

  17. Comparison of distribution and toxicity following repeated oral dosing of different vanadium oxide nanoparticles in mice

    Energy Technology Data Exchange (ETDEWEB)

    Park, Eun-Jung, E-mail: pejtoxic@hanmail.net [Myunggok Eye Research Institute, Konyang University, Daejeon 302-718 (Korea, Republic of); Lee, Gwang-Hee [School of Civil, Environmental, and Architectural Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Yoon, Cheolho [Seoul Center, Korea Basic Science Institute, Seoul 126-16 (Korea, Republic of); Kim, Dong-Wan, E-mail: dwkim1@korea.ac.kr [School of Civil, Environmental, and Architectural Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2016-10-15

    Vanadium is an important ultra-trace element derived from fuel product combustion. With the development of nanotechnology, vanadium oxide nanoparticles (VO NPs) have been considered for application in various fields, thus the possibility of release into the environment and human exposure is also increasing. Considering that verification of bioaccumulation and relevant biological responses are essential for safe application of products, in this study, we aimed to identify the physicochemical properties that determine their health effects by comparing the biological effects and tissue distribution of different types of VO NPs in mice. For this, we prepared five types of VO NPs, commercial (C)-VO{sub 2} and -V{sub 2}O{sub 5} NPs and synthetic (S)-VO{sub 2}, -V{sub 2}O{sub 3,} and -V{sub 2}O{sub 5} NPs. While the hydrodynamic diameter of the two types of C-VO NPs was irregular and impossible to measure, those of the three types of S-VO NPs was in the range of 125–170 nm. The S- and C-V{sub 2}O{sub 5} NPs showed higher dissolution rates compared to other VO NPs. We orally dosed the five types of VO NPs (70 and 210 μg/mouse, approximately 2 and 6 mg/kg) to mice for 28 days and compared their biodistribution and toxic effects. We found that S-V{sub 2}O{sub 5} and S-V{sub 2}O{sub 3} NPs more accumulated in tissues compared to other three types of VO NPs, and the accumulated level was in order of heart>liver>kidney>spleen. Additionally, tissue levels of redox reaction-related elements and electrolytes (Na{sup +}, K{sup +}, and Ca{sup 2+}) were most clearly altered in the heart of treated mice. Notably, all S- and C-VO NPs decreased the number of WBCs at the higher dose, while total protein and albumin levels were reduced at the higher dose of S-V{sub 2}O{sub 5} and S-V{sub 2}O{sub 3} NPs. Taken together, we conclude that the biodistribution and toxic effects of VO NPs depend on their dissolution rates and size (surface area). Additionally, we suggest that further studies

  18. Evaluating the Zebrafish Embryo Toxicity Test for Pesticide Hazard Screening

    Science.gov (United States)

    Given the numerous chemicals used in society, it is critical to develop tools for accurate and efficient evaluation of potential risks to human and ecological receptors. Fish embryo acute toxicity tests are 1 tool that has been shown to be highly predictive of standard, more reso...

  19. Review of the use of Ceramium tenuicorne growth inhibition test for testing toxicity of substances, effluents, products sediment and soil

    Science.gov (United States)

    Eklund, Britta

    2017-08-01

    A growth inhibition test has been developed based on two clones of the red macroalga Ceramium tenuicorne, one originating from 7 PSU and the other from 20 PSU. The species can be adapted to different salinities and the test can be carried out between 4 and 32 PSU. This test became an ISO standard in 2010 (ISO 107 10) for testing of chemicals and water effluents. In this study new and published data has been compiled on toxicity of single substances, waste waters from pulp mills, leachates from antifouling paints, harbour sediments and soil used for maintenance of leisure boats. The results show that the alga is sensitive to both metals and organic compounds and to biocides used in antifouling paints. By testing leachates from antifouling paints these could be ranked according to their toxicity. Similarly, the toxicity of waste waters from pulp mills was determined and the efficiency of secondary treatment evaluated. Further, the test method proved useful to test the toxicity in sediment samples. Sediments from small town harbours and ship lanes were shown to be harmful and compounds originating from antifouling paints were responsible for a large part of the inhibiting effect. The alga proved to be sensitive to contaminants leaking from boat yard soil. The growth inhibition test is a robust test that has high repeatability and reproducibility and easily can be applied on water, soil and sediment samples without being too costly. The species is found worl-wide in temperate waters, which makes the results relevant for large areas. In the Baltic Sea C. tenuicorne is the most common red alga species and is thus particularly relevant for this area. The overall results show that contaminants from boat activities and the use of antifouling paints in particular pose a threat to the environment.

  20. Single and 2-week repeated intravenous dose toxicity studies of disodium mercaptoundecahydro-closo-dodecaborate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Fumio; Yabuuchi, Kazuya; Ohno, Kouji; Muraoka, Yoshihiro [Shionogi and Co. Ltd., Toyonaka, Osaka (Japan). Developmental Research Lab.; Ikeuchi, Isao

    1998-10-01

    Disodium mercaptoundecahydro-closo-dodecaborate (BSH) is a boron compound used in Boron Neutron Capture Therapy for malignant brain tumors. Intravenous single and 2-week repeated dose toxicity studies of BSH were performed in Sprague-Dawley rats. In the single-dose study, BSH was administered at doses of 100, 300 or 600 mg/kg. Death occurred within 10 min (acute type) or from 5 hr to 2 days (delayed type) after dosing in the 600 mg/kg group. No differences in mortality by sex and dosing speed were observed. Major causes of death were considered to be circulatory disorder in acute death and renal injury in delayed death. The renal injury was observed in the 300 and 600 mg/kg groups. In the 2-week repeated dose study, BSH was administered at doses of 30, 100 or 300 mg/kg/day for 14 days. Body weight gain was suppressed in the 100 and 300 mg/kg groups. One male in the 300 mg/kg group died due to renal and pulmonary lesions at day 8. Slight anemia was observed in the 300 mg/kg group. Pathologically, the kidney showed tubular regeneration with increase of weight in the 300 mg/kg. From these results, the NOAEL of BSH is 30 mg/kg/day. (author)

  1. 40 CFR 799.9305 - TSCA Repeated dose 28-day oral toxicity study in rodents.

    Science.gov (United States)

    2010-07-01

    ... considered necessary. The limit test applies except when human exposure indicates the need for a higher dose..., stereotypies (e.g., excessive grooming, repetitive circling) or bizarre behaviour (e.g., self-mutilation...

  2. Improvement in Shrimp Hatchery Procedures for Toxicity Tests

    International Nuclear Information System (INIS)

    Nor Azizah Marsiddi; Fazliana Mohd Saaya; Anee Suryani Sued

    2015-01-01

    Toxicity testing of brine shrimp Artemia salina Brine shrimp lethality assay is a screening test to determine half the dose mortality (LC50) for its shrimp given certain herbal extract at a concentration tested. The shrimp child mortality half a dose indicator to determine level of toxicity before further testing done on animal cell culture and animal experiments also on the mouse. The use of new hardware, namely Artemio 1 has increased its shrimp production at a rate that more and faster than the use of the black box hatching previously taken from the method by Solis, 1993. brine shrimp eggs from Artemio mix also easier to use because it contains egg and sea salt have been ready mixed for use in experiments. In conclusion, this method improvements help increase the number of offspring produced shrimp and produce experimental method easier than previous methods. (author)

  3. Repeat HIV Testing at Voluntary Testing and Counseling Centers in Croatia: Successful HIV Prevention or Failure to Modify Risk Behaviors?

    Science.gov (United States)

    Matković Puljić, Vlatka; Kosanović Ličina, Mirjana Lana; Kavić, Marija; Nemeth Blažić, Tatjana

    2014-01-01

    HIV testing plays a critical role in preventing the spread of the virus and identifying infected individuals in need of care. Voluntary counseling and testing centers (VCTs) not only conduct testing but they also provide counseling. Since a proportion of people who test negative for HIV on their previous visit will return for retesting, the frequency of retesting and the characteristics of those who retest may provide insights into the efficacy of testing and counseling strategies. In this cross-sectional, retrospective study of 1,482 VCT clients in Croatia in 2010, 44.3% had been tested for HIV before. The rate of repeat HIV testing is lower in Croatia than in other countries. Men who have sex with men (MSM) clients, those with three or more sexual partners in the last 12 months, consistent condom users with steady partners, and intravenous drug users were more likely to be repeat testers. This finding suggests that clients presenting for repeat HIV testing are those who self-identify as being at a higher risk of infection. Our data showed that testing positive for HIV was not associated with repeat testing. However, the effects of repeat testing on HIV epidemiology needs to be explored. PMID:24705595

  4. Collaborative work on evaluation of ovarian toxicity. 13) Two- or four-week repeated dose studies and fertility study of PPAR alpha/gamma dual agonist in female rats.

    Science.gov (United States)

    Sato, Norihiro; Uchida, Keisuke; Nakajima, Mikio; Watanabe, Atsushi; Kohira, Terutomo

    2009-01-01

    The main focus of this study was to determine the optimal dosing period in a repeated dose toxicity study based on toxic effects as assessed by ovarian morphological changes. To assess morphological and functional changes induced in the ovary by a peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, the compound was administered to female rats at dose levels of 0, 4, 20, and 100 mg/kg/day in a repeated dose toxicity study for 2 or 4 weeks, and from 2 weeks prior to mating to Day 7 of pregnancy in a female fertility study. In the repeated dose toxicity study, an increase in atresia of large follicles, a decrease in corpora lutea, and an increase in stromal cells were observed in the treated groups. In addition, the granulosa cell exfoliations into antrum of large follicles and corpora lutea with retained oocyte are morphological characteristics induced by this compound, and they might be related with abnormal condition of ovulation. In the female fertility study, the pregnancy rate tended to decrease in the 100 mg/kg/day group. At necropsy, decreases in the number of corpora lutea, implantations and live embryos were noted in the 20 and 100 mg/kg/day group. No changes were observed in animals given 4 mg/kg/day. These findings indicated that histopathological changes in the ovary are important endpoints for evaluation of drugs inducing ovarian damage. In conclusion, a 2-week administration period is sufficient to detect ovarian toxicity of this test compound in the repeated dose toxicity study.

  5. Repeated patch testing to nickel during childhood do not induce nickel sensitization

    DEFF Research Database (Denmark)

    Søgaard Christiansen, Elisabeth

    2014-01-01

    Background: Previously, patch test reactivity to nickel sulphate in a cohort of unselected infants tested repeatedly at 3-72 months of age has been reported. A reproducible positive reaction at 12 and 18 months was selected as a sign of nickel sensitivity, provided a patch test with an empty Finn...

  6. Indicators of Ceriodaphnia dubia chronic toxicity test performance and sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Rosebrock, M.M.; Bedwell, N.J.; Ausley, L.W. [North Carolina Division of Environmental Management, Raleigh, NC (United States)

    1994-12-31

    The North Carolina Division of Environmental Management has begun evaluation of the sensitivity of test results used for measuring chronic whole effluent toxicity in North Carolina wastewater discharges. Approximately 67% of 565 facilities required to monitor toxicity by an NPDES permit perform a Ceriodaphnia dubia chronic, single effluent concentration (pass/fail) analysis. Data from valid Ceriodaphnia dubia chronic pass/fail tests performed by approximately 20 certified biological laboratories and submitted by North Carolina NPDES permittees were recorded beginning January 1992. Control and treatment reproduction data from over 2,500 tests submitted since 1992 were analyzed to determine the minimum significant difference (MSD) at a 99% confidence level for each test and the percent reduction from the control mean that the MSD represents (%MSD) for each certified laboratory. Initial results for the 20 laboratories indicate that the average intralaboratory percent MSD ranges 12.72% (n = 367) to 34.91% (n = 7) with an average of 23.08%. Additionally, over 3,800 tests were analyzed to determine the coefficient of variation (CV) for control reproduction for each test and the average for each certified biological laboratory. Preliminary review indicates that average interlaboratory control reproduction CV values range from 10.59% (n = 367) to 31.08% (n = 572) with a mean of 20.35%. The statistics investigated are indicators of intra/interlaboratory performance and sensitivity of Ceriodaphnia chronic toxicity analyses.

  7. An evaluation of the whole effluent toxicity test method

    International Nuclear Information System (INIS)

    Osteen, D.V.

    1999-01-01

    Whole effluent toxicity (WET) testing has become increasingly more important to the Environmental Protection Agency (EPA) and the States in the permitting of wastewater discharges from industry and municipalities. The primary purpose of the WET test is to protect aquatic life by predicting the effect of an effluent on the receiving stream. However, there are both scientific and regulatory concerns that using WET tests to regulate industrial effluents may result in either false positives and/or false negatives. In order to realistically predict the effect of an effluent on the receiving stream, the test should be as representative as possible of the conditions in the receiving stream. Studies (Rand and Petrocelli 1985) suggested several criteria for an ideal aquatic toxicity test organism, one of which is that the organism be indigenous to, or representative of, the ecosystem receiving the effluent. The other component needed in the development of a predictive test is the use of the receiving stream water or similar synthetic water as the control and dilution water in the test method. Use of an indigenous species and receiving water in the test should help reduce the variability in the method and allow the test to predict the effect of the effluent on the receiving stream. The experience with toxicity testing at the Savannah River Site (SRS) has yielded inconclusive data because of the inconsistency and unreliability of the results. The SRS contention is that the WET method in its present form does not adequately mimic actual biological/chemical conditions of the receiving streams and is neither reasonable nor accurate. This paper discusses the rationale for such a position by SRS on toxicity testing in terms of historical permitting requirements, outfall effluent test results, standard test method evaluation, scientific review of alternate test species, and concerns over the test method expressed by other organizations. This paper presents the Savannah River Site

  8. In vitro pyrogen test for toxic or immunomodulatory drugs

    OpenAIRE

    Daneshian, Mardas; Guenther, Armin; Wendel, Albrecht; Hartung, Thomas; Aulock, Sonja von

    2006-01-01

    Pyrogenic contaminations of some classes of injectable drugs, e.g. toxic or immunomodulatory as well as false-positive drugs, represent a major risk which cannot yet be excluded due to the limitations of current tests. Here we describe a modification of the In vitro Pyrogen Test termed AWIPT (Adsorb, Wash, In vitro Pyrogen Test), which addresses this problem by introducing a pre-incubation step in which pyrogenic contaminations in the test sample are adsorbed to albumin-coated beads. After ri...

  9. Lesser Neural Pattern Similarity across Repeated Tests Is Associated with Better Long-Term Memory Retention.

    Science.gov (United States)

    Karlsson Wirebring, Linnea; Wiklund-Hörnqvist, Carola; Eriksson, Johan; Andersson, Micael; Jonsson, Bert; Nyberg, Lars

    2015-07-01

    Encoding and retrieval processes enhance long-term memory performance. The efficiency of encoding processes has recently been linked to representational consistency: the reactivation of a representation that gets more specific each time an item is further studied. Here we examined the complementary hypothesis of whether the efficiency of retrieval processes also is linked to representational consistency. Alternatively, recurrent retrieval might foster representational variability--the altering or adding of underlying memory representations. Human participants studied 60 Swahili-Swedish word pairs before being scanned with fMRI the same day and 1 week later. On Day 1, participants were tested three times on each word pair, and on Day 7 each pair was tested once. A BOLD signal change in right superior parietal cortex was associated with subsequent memory on Day 1 and with successful long-term retention on Day 7. A representational similarity analysis in this parietal region revealed that beneficial recurrent retrieval was associated with representational variability, such that the pattern similarity on Day 1 was lower for retrieved words subsequently remembered compared with those subsequently forgotten. This was mirrored by a monotonically decreased BOLD signal change in dorsolateral prefrontal cortex on Day 1 as a function of repeated successful retrieval for words subsequently remembered, but not for words subsequently forgotten. This reduction in prefrontal response could reflect reduced demands on cognitive control. Collectively, the results offer novel insights into why memory retention benefits from repeated retrieval, and they suggest fundamental differences between repeated study and repeated testing. Repeated testing is known to produce superior long-term retention of the to-be-learned material compared with repeated encoding and other learning techniques, much because it fosters repeated memory retrieval. This study demonstrates that repeated memory

  10. Non-animal Replacements for Acute Toxicity Testing.

    Science.gov (United States)

    Barker-Treasure, Carol; Coll, Kevin; Belot, Nathalie; Longmore, Chris; Bygrave, Karl; Avey, Suzanne; Clothier, Richard

    2015-07-01

    Current approaches to predicting adverse effects in humans from acute toxic exposure to cosmetic ingredients still heavily necessitate the use of animals under EU legislation, particularly in the context of the REACH system, when cosmetic ingredients are also destined for use in other industries. These include the LD50 test, the Up-and-Down Procedure and the Fixed Dose Procedure, which are regarded as having notable scientific deficiencies and low transferability to humans. By expanding on previous in vitro tests, such as the animal cell-based 3T3 Neutral Red Uptake (NRU) assay, this project aims to develop a truly animal-free predictive test for the acute toxicity of cosmetic ingredients in humans, by using human-derived cells and a prediction model that does not rely on animal data. The project, funded by Innovate UK, will incorporate the NRU assay with human dermal fibroblasts in animal product-free culture, to generate an in vitro protocol that can be validated as an accepted replacement for the currently available in vivo tests. To date, the project has successfully completed an assessment of the robustness and reproducibility of the method, by using sodium lauryl sulphate (SLS) as a positive control, and displaying analogous results to those of the original studies with mouse 3T3 cells. Currently, the testing of five known ingredients from key groups (a surfactant, a preservative, a fragrance, a colour and an emulsifier) is under way. The testing consists of initial range-finding runs followed by three valid runs of a main experiment with the appropriate concentration ranges, to generate IC50 values. Expanded blind trials of 20 ingredients will follow. Early results indicate that this human cell-based test holds the potential to replace aspects of in vivo animal acute toxicity testing, particularly with reference to cosmetic ingredients. 2015 FRAME.

  11. Undetected Toxicity Risk in Pharmacogenetic Testing for Dihydropyrimidine Dehydrogenase

    Directory of Open Access Journals (Sweden)

    Felicia Stefania Falvella

    2015-04-01

    Full Text Available Fluoropyrimidines, the mainstay agents for the treatment of colorectal cancer, alone or as a part of combination therapies, cause severe adverse reactions in about 10%–30% of patients. Dihydropyrimidine dehydrogenase (DPD, a key enzyme in the catabolism of 5-fluorouracil, has been intensively investigated in relation to fluoropyrimidine toxicity, and several DPD gene (DPYD polymorphisms are associated with decreased enzyme activity and increased risk of fluoropyrimidine-related toxicity. In patients carrying non-functional DPYD variants (c.1905+1G>A, c.1679T>G, c.2846A>T, fluoropyrimidines should be avoided or reduced according to the patients’ homozygous or heterozygous status, respectively. For other common DPYD variants (c.496A>G, c.1129-5923C>G, c.1896T>C, conflicting data are reported and their use in clinical practice still needs to be validated. The high frequency of DPYD polymorphism and the lack of large prospective trials may explain differences in studies’ results. The epigenetic regulation of DPD expression has been recently investigated to explain the variable activity of the enzyme. DPYD promoter methylation and its regulation by microRNAs may affect the toxicity risk of fluoropyrimidines. The studies we reviewed indicate that pharmacogenetic testing is promising to direct personalised dosing of fluoropyrimidines, although further investigations are needed to establish the role of DPD in severe toxicity in patients treated for colorectal cancer.

  12. Toxicity tests, antioxidant activity, and antimicrobial activity of chitosan

    Science.gov (United States)

    Kurniasih, M.; Purwati; Dewi, R. S.

    2018-04-01

    Chitosan is a naturally occurring cationic biopolymer, obtained by alkaline deacetylation of chitin. This research aims to investigate the toxicity, antioxidant activity and antibacterial activity of chitosan from shrimp chitin. In this study, chitin extracted from shrimp waste material. Chitin is then deacetylation with 60% NaOH so that chitosan produced. Degrees of deacetylation, molecular weight, toxicity test, antioxidant activity and antimicrobial activity of chitosan then evaluated. Toxicity test using Brine Shrimp Lethality Test. The antioxidant analysis was performed using DPPH method (2, 2-diphenyl-1-picrylhydrazyl) and FTC method (ferric thiocyanate) in which the radical formed will reduce Ferro to Ferri resulting in a complex with thiocyanate. To determine the antibacterial activity of Staphylococcus aureus, antifungal in Candida albicans and Aspergillus niger by measuring antimicrobial effects and minimum inhibitory concentrations (MIC). Based on the result of research, the value of degrees of deacetylation, molecular weight, and LC50 values of chitosan synthesis was 94,32, 1052.93 g/mol and 1364.41 ppm, respectively. In general, the antioxidative activities increased as the concentration of chitosan increased. MIC value of chitosan against S. aureus, C. albicans, and A. niger was 10 ppm, 15.6 ppm, and 5 ppm, respectively.

  13. Studying the effect of CO2-induced acidification on sediment toxicity using acute amphipod toxicity test.

    Science.gov (United States)

    Basallote, M Dolores; De Orte, Manoela R; DelValls, T Ángel; Riba, Inmaculada

    2014-01-01

    Carbon capture and storage is increasingly being considered one of the most efficient approaches to mitigate the increase of CO2 in the atmosphere associated with anthropogenic emissions. However, the environmental effects of potential CO2 leaks remain largely unknown. The amphipod Ampelisca brevicornis was exposed to environmental sediments collected in different areas of the Gulf of Cádiz and subjected to several pH treatments to study the effects of CO2-induced acidification on sediment toxicity. After 10 days of exposure, the results obtained indicated that high lethal effects were associated with the lowest pH treatments, except for the Ría of Huelva sediment test. The mobility of metals from sediment to the overlying seawater was correlated to a pH decrease. The data obtained revealed that CO2-related acidification would lead to lethal effects on amphipods as well as the mobility of metals, which could increase sediment toxicity.

  14. Long-term repeatability of the skin prick test is high when supported by history or allergen-sensitivity tests

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Jacobsen, C R; Poulsen, L K

    2003-01-01

    subjects. An SPT was positive when > or =3 mm, and repeatable if either persistently positive or negative. Clinical sensitivity to birch pollen was used as model for inhalation allergy, and was investigated at inclusion and at study termination by challenge tests, intradermal test, titrated SPT and Ig......E measurements. Birch pollen symptoms were confirmed in diaries. RESULTS: The repeatability of a positive SPT was 67%, increasing significantly to 100% when supported by the history. When not supported by history, the presence of specific IgE was significantly associated with a repeatable SPT. Allergen....... CONCLUSION: SPT changes are clinically relevant. Further studies using other allergens are needed. Long-term repeatability of SPT is high in the presence of a supportive history....

  15. Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment

    NARCIS (Netherlands)

    Chaudhari, U.; Nemade, H.; Wagh, V.; Ellis, J.K.; Srinivasan, S.; Louisse, J.

    2016-01-01

    The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the

  16. New and emerging technologies for genetic toxicity testing.

    Science.gov (United States)

    Lynch, Anthony M; Sasaki, Jennifer C; Elespuru, Rosalie; Jacobson-Kram, David; Thybaud, Véronique; De Boeck, Marlies; Aardema, Marilyn J; Aubrecht, Jiri; Benz, R Daniel; Dertinger, Stephen D; Douglas, George R; White, Paul A; Escobar, Patricia A; Fornace, Albert; Honma, Masamitsu; Naven, Russell T; Rusling, James F; Schiestl, Robert H; Walmsley, Richard M; Yamamura, Eiji; van Benthem, Jan; Kim, James H

    2011-04-01

    The International Life Sciences Institute (ILSI) Health and Environmental Sciences Institute (HESI) Project Committee on the Relevance and Follow-up of Positive Results in In Vitro Genetic Toxicity (IVGT) Testing established an Emerging Technologies and New Strategies Workgroup to review the current State of the Art in genetic toxicology testing. The aim of the workgroup was to identify promising technologies that will improve genotoxicity testing and assessment of in vivo hazard and risk, and that have the potential to help meet the objectives of the IVGT. As part of this initiative, HESI convened a workshop in Washington, DC in May 2008 to discuss mature, maturing, and emerging technologies in genetic toxicology. This article collates the abstracts of the New and Emerging Technologies Workshop together with some additional technologies subsequently considered by the workgroup. Each abstract (available in the online version of the article) includes a section addressed specifically to the strengths, weaknesses, opportunities, and threats associated with the respective technology. Importantly, an overview of the technologies and an indication of how their use might be aligned with the objectives of IVGT are presented. In particular, consideration was given with regard to follow-up testing of positive results in the standard IVGT tests (i.e., Salmonella Ames test, chromosome aberration assay, and mouse lymphoma assay) to add weight of evidence and/or provide mechanism of action for improved genetic toxicity risk assessments in humans. Copyright © 2010 Wiley-Liss, Inc.

  17. Development and validation of OECD test guidelines on mollusc reproductive toxicity tests

    DEFF Research Database (Denmark)

    Lagadic, Laurent; Holbech, Henrik; hutchinson, tom

    the comparison of endpoints relevant for reproduction in invertebrates often shows a much higher sensitivity in molluscs vs. e.g. daphnids. The OECD test guideline programme has thus been extended to cover reproduction effects of chemicals in molluscs. Existing mollusc toxicity test protocols have been reviewed...... in an OECD Detailed Review Paper that identifies two relevant candidate species for developing freshwater tests: Potamopyrgus antipodarum and Lymnaea stagnalis. However, this review did not clarify which toxicity test design/conditions are the most appropriate for chemicals assessment. Therefore, a mollusc...... reproduction test guideline will be developed describing partial- and full- life-cycle test protocols in these species, so as to propose a balanced suite of apical mollusc toxicity tests applicable for the assessment of any type of chemical, including endocrine disruptors, as level 4 and 5 assays of the EDTA...

  18. Collection and cultivation methods of Acartia tonsa for toxicity testing

    International Nuclear Information System (INIS)

    Hood, C.A.; Mayo, R.R.

    1995-01-01

    Acartia tonsa were located and collected from Galveston Bay, Texas in June 1995, using plankton nets and transported to the laboratory for culture. After literature searching and laboratory experimentation. A simple reliable method was designed to culture A. tonsa. This method requires a minimum of glassware and supplies. Adult A. tonsa are placed in one gallon bell jars filled with natural seawater. The jars are then maintained in a water bath at a constant temperature. Water changes are conducted twice weekly and organisms are fed daily with a mixture of algae, Skeletonema costatum, isocrysis galbana, and Thalassiosira sp. Gravid females are then isolated in generators for 24 hours to obtain known age neonates. The neonates are maintained up to a specific age and then are used in toxicity tests such as the ''Determination of the Acute Lethal Toxicity to Marine Copepods,'' required in the United Kingdom for all chemicals used for offshore drilling fluid applications

  19. Subjective and objective screening tests for hydroxychloroquine toxicity.

    Science.gov (United States)

    Cukras, Catherine; Huynh, Nancy; Vitale, Susan; Wong, Wai T; Ferris, Fredrick L; Sieving, Paul A

    2015-02-01

    To compare subjective and objective clinical tests used in the screening for hydroxychloroquine retinal toxicity to multifocal electroretinography (mfERG) reference testing. Prospective, single-center, case control study. Fifty-seven patients with a previous or current history of hydroxychloroquine treatment of more than 5 years' duration. Participants were evaluated with a detailed medical history, dilated ophthalmologic examination, color fundus photography, fundus autofluorescence (FAF) imaging, spectral-domain (SD) optical coherence tomography (OCT), automated visual field testing (10-2 visual field mean deviation [VFMD]), and mfERG testing. We used mfERG test parameters as a gold standard to divide participants into 2 groups: those affected by hydroxychloroquine-induced retinal toxicity and those unaffected. We assessed the association of various imaging and psychophysical variables in the affected versus the unaffected group. Fifty-seven study participants (91.2% female; mean age, 55.7±10.4 years; mean duration of hydroxychloroquine treatment, 15.0±7.5 years) were divided into affected (n = 19) and unaffected (n = 38) groups based on mfERG criteria. Mean age and duration of hydroxychloroquine treatment did not differ statistically between groups. Mean OCT retinal thickness measurements in all 9 macular subfields were significantly lower (<40 μm) in the affected group (P < 0.01 for all comparisons) compared with those in the unaffected group. Mean VFMD was 11 dB lower in the affected group (P < 0.0001). Clinical features indicative of retinal toxicity were scored for the 2 groups and were detected in 68.4% versus 0.0% using color fundus photographs, 73.3% versus 9.1% using FAF images, and 84.2% versus 0.0% on the scoring for the perifoveal loss of the photoreceptor ellipsoid zone on SD-OCT for affected and unaffected participants, respectively. Using a polynomial modeling approach, OCT inner ring retinal thickness measurements and Humphrey 10-2 VFMD were

  20. Tracking pyrethroid toxicity in surface water samples: Exposure dynamics and toxicity identification tools for laboratory tests with Hyalella azteca (Amphipoda).

    Science.gov (United States)

    Deanovic, Linda A; Stillway, Marie; Hammock, Bruce G; Fong, Stephanie; Werner, Inge

    2018-02-01

    Pyrethroid insecticides are commonly used in pest control and are present at toxic concentrations in surface waters of agricultural and urban areas worldwide. Monitoring is challenging as a result of their high hydrophobicity and low toxicity thresholds, which often fall below the analytical methods detection limits (MDLs). Standard daphnid bioassays used in surface water monitoring are not sensitive enough to protect more susceptible invertebrate species such as the amphipod Hyalella azteca and chemical loss during toxicity testing is of concern. In the present study, we quantified toxicity loss during storage and testing, using both natural and synthetic water, and presented a tool to enhance toxic signal strength for improved sensitivity of H. azteca toxicity tests. The average half-life during storage in low-density polyethylene (LDPE) cubitainers (Fisher Scientific) at 4 °C of 5 pyrethroids (permethrin, bifenthrin, lambda-cyhalothrin, cyfluthrin, and esfenvalerate) and one organophosphate (chlorpyrifos; used as reference) was 1.4 d, and piperonyl butoxide (PBO) proved an effective tool to potentiate toxicity. We conclude that toxicity tests on ambient water samples containing these hydrophobic insecticides are likely to underestimate toxicity present in the field, and mimic short pulse rather than continuous exposures. Where these chemicals are of concern, the addition of PBO during testing can yield valuable information on their presence or absence. Environ Toxicol Chem 2018;37:462-472. © 2017 SETAC. © 2017 SETAC.

  1. Computational systems biology and dose-response modeling in relation to new directions in toxicity testing.

    Science.gov (United States)

    Zhang, Qiang; Bhattacharya, Sudin; Andersen, Melvin E; Conolly, Rory B

    2010-02-01

    The new paradigm envisioned for toxicity testing in the 21st century advocates shifting from the current animal-based testing process to a combination of in vitro cell-based studies, high-throughput techniques, and in silico modeling. A strategic component of the vision is the adoption of the systems biology approach to acquire, analyze, and interpret toxicity pathway data. As key toxicity pathways are identified and their wiring details elucidated using traditional and high-throughput techniques, there is a pressing need to understand their qualitative and quantitative behaviors in response to perturbation by both physiological signals and exogenous stressors. The complexity of these molecular networks makes the task of understanding cellular responses merely by human intuition challenging, if not impossible. This process can be aided by mathematical modeling and computer simulation of the networks and their dynamic behaviors. A number of theoretical frameworks were developed in the last century for understanding dynamical systems in science and engineering disciplines. These frameworks, which include metabolic control analysis, biochemical systems theory, nonlinear dynamics, and control theory, can greatly facilitate the process of organizing, analyzing, and understanding toxicity pathways. Such analysis will require a comprehensive examination of the dynamic properties of "network motifs"--the basic building blocks of molecular circuits. Network motifs like feedback and feedforward loops appear repeatedly in various molecular circuits across cell types and enable vital cellular functions like homeostasis, all-or-none response, memory, and biological rhythm. These functional motifs and associated qualitative and quantitative properties are the predominant source of nonlinearities observed in cellular dose response data. Complex response behaviors can arise from toxicity pathways built upon combinations of network motifs. While the field of computational cell

  2. Development of a REBCO HTS magnet for Maglev - repeated bending tests of HTS pancake coils -

    Science.gov (United States)

    Sugino, Motohikoa; Mizuno, Katsutoshi; Tanaka, Minoru; Ogata, Masafumi

    2018-01-01

    In the past study, two manufacturing methods were developed that can manufacture pancake coils by using REBCO coated conductors. It was confirmed that the conductors have no electric degradation that caused by the manufacturing method. The durability evaluation tests of the pancake coils were conducted as the final evaluation of the coil manufacturing method in this study. The repeated bending deformation was applied to manufactured pancake coils in the tests. As the results of these tests, it was confirmed that the pancake coils that were manufactured by two methods had the durability for the repeated bending deformation and the coils maintained the appropriate mechanical performance and electric performance. We adopted the fusion bonding method as the coil manufacturing method of the HTS magnet Furthermore, using the prototype pancake coil that was manufactured by the fusion bonding method as a test sample, the repeated bending test under the exited condition was conducted. Thus it was confirmed that the coil manufactured by the fusion bonding method has no degradation of the electricity performance and the mechanical properties even if the repeated bending deformation was applied under the exited condition.

  3. OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing

    NARCIS (Netherlands)

    Busquet, F.; Strecker, R.; Rawlings, J.M.; Belanger, S.E.; Braunbeck, T.; Carr, G.J.; Cenijn, P.H.; Fochtman, P.; Gourmelon, A.; Hübler, N.; Kleensang, A.; Knöbel, M.; Kussatz, C.; Legler, J.; Lillicrap, A.; Martínez-Jerónimo, F.; Polleichtner, C.; Rzodeczko, H.; Salinas, E.; Schneider, K.E.; Scholz, S.; van den Brandhof, E.J.; van der Ven, L.T.; Walter-Rohde, S.; Weigt, S.; Witters, H.; Halder, M.

    2014-01-01

    A The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were

  4. A REVIEW OF SINGLE SPECIES TOXICITY TESTS: ARE THE TESTS RELIABLE PREDICTORS OF AQUATIC ECOSYSTEM COMMUNITY RESPONSES?

    Science.gov (United States)

    This document provides a comprehensive review to evaluate the reliability of indicator species toxicity test results in predicting aquatic ecosystem impacts, also called the ecological relevance of laboratory single species toxicity tests.

  5. Combinatorial QSAR modeling of chemical toxicants tested against Tetrahymena pyriformis.

    Science.gov (United States)

    Zhu, Hao; Tropsha, Alexander; Fourches, Denis; Varnek, Alexandre; Papa, Ester; Gramatica, Paola; Oberg, Tomas; Dao, Phuong; Cherkasov, Artem; Tetko, Igor V

    2008-04-01

    Selecting most rigorous quantitative structure-activity relationship (QSAR) approaches is of great importance in the development of robust and predictive models of chemical toxicity. To address this issue in a systematic way, we have formed an international virtual collaboratory consisting of six independent groups with shared interests in computational chemical toxicology. We have compiled an aqueous toxicity data set containing 983 unique compounds tested in the same laboratory over a decade against Tetrahymena pyriformis. A modeling set including 644 compounds was selected randomly from the original set and distributed to all groups that used their own QSAR tools for model development. The remaining 339 compounds in the original set (external set I) as well as 110 additional compounds (external set II) published recently by the same laboratory (after this computational study was already in progress) were used as two independent validation sets to assess the external predictive power of individual models. In total, our virtual collaboratory has developed 15 different types of QSAR models of aquatic toxicity for the training set. The internal prediction accuracy for the modeling set ranged from 0.76 to 0.93 as measured by the leave-one-out cross-validation correlation coefficient ( Q abs2). The prediction accuracy for the external validation sets I and II ranged from 0.71 to 0.85 (linear regression coefficient R absI2) and from 0.38 to 0.83 (linear regression coefficient R absII2), respectively. The use of an applicability domain threshold implemented in most models generally improved the external prediction accuracy but at the same time led to a decrease in chemical space coverage. Finally, several consensus models were developed by averaging the predicted aquatic toxicity for every compound using all 15 models, with or without taking into account their respective applicability domains. We find that consensus models afford higher prediction accuracy for the

  6. Evaluation of Patients with an Apparent False Positive Stool DNA Test: The Role of Repeat Stool DNA Testing.

    Science.gov (United States)

    Cooper, Gregory S; Markowitz, Sanford D; Chen, Zhengyi; Tuck, Missy; Willis, Joseph E; Berger, Barry M; Brenner, Dean E; Li, Li

    2018-03-07

    There is uncertainty as to the appropriate follow-up of patients who test positive on multimarker stool DNA (sDNA) testing and have a colonoscopy without neoplasia. To determine the prevalence of missed colonic or occult upper gastrointestinal neoplasia in patients with an apparent false positive sDNA. We prospectively identified 30 patients who tested positive with a commercially available sDNA followed by colonoscopy without neoplastic lesions. Patients were invited to undergo repeat sDNA at 11-29 months after the initial test followed by repeat colonoscopy and upper endoscopy. We determined the presence of neoplastic lesions on repeat evaluation stratified by results of repeat sDNA. Twelve patients were restudied. Seven patients had a negative second sDNA test and a normal second colonoscopy and upper endoscopy. In contrast, 5 of 12 subjects had a persistently positive second sDNA test, and 3 had positive findings, including a 3-cm sessile transverse colon adenoma with high-grade dysplasia, a 2-cm right colon sessile serrated adenoma with dysplasia, and a nonadvanced colon adenoma (p = 0.045). These corresponded to a positive predictive value of 0.60 (95% CI 0.17-1.00) and a negative predictive value of 1.00 (95% CI 1.00-1.00) for the second sDNA test. In addition, the medical records of all 30 subjects with apparent false positive testing were reviewed and no documented cases of malignant tumors were recorded. Repeat positive sDNA testing may identify a subset of patients with missed or occult colorectal neoplasia after negative colonoscopy for an initially positive sDNA. High-quality colonoscopy with careful attention to the right colon in patients with positive sDNA is critically important and may avoid false negative colonoscopy.

  7. Guanicid and PHMG Toxicity Tests on Aquatic Organisms

    Directory of Open Access Journals (Sweden)

    Eva Poštulková

    2016-01-01

    Full Text Available The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG. The aim of the study was to identify toxic effects of Guanicid and PHMG on zebrafish (Danio rerio and green algae (Desmodesmus communis. We determined the acute toxicity in fish according to ČSN EN ISO 7346-1, and conducted the freshwater algae growth inhibition test according to ČSN ISO 8692 methodology. For inhibition tests with green algae we chose Guanicid and PHMG concentrations of 0.001, 0.005, and 0.010 ml/L. For fish short-term acute toxicity tests we chose Guanicid concentrations of 0.010, 0.050, 0.150, 0.200, 0.250, and 0.300 ml/L and PHMG concentrations of 0.010, 0.025, 0.050, 0.075, 0.100, and 0.125 ml/L. In case of zebrafish (Danio rerio, the LC50 value for Guanicid is 0.086 ml/L, while the LC50 value for PHMG is 0.043 ml/L. Effects of Guanicid on inhibition of green algae (Desmodesmus communis appear highly significant (p < 0.010 at a concentration of 0.010 ml/L. For PHMG, these effects are highly significant (p < 0.001 at concentrations of 0.005 and 0.010 ml/L in 48 hours.

  8. Tests for oil/dispersant toxicity: In situ laboratory assays

    International Nuclear Information System (INIS)

    Wright, D.A.; Coelho, G.M.; Aurand, D.V.

    1995-01-01

    As part of its readiness program in oil spill response, the Marine Pollution Control Unit (MPCU), Department of Transport, U.K. conducts annual field trials in the North Sea, approximately 30 nautical miles from the southeast coast of England. The trials take the form of controlled releases of crude oil or Medium Fuel/Gas Oil mix (MFO), with and without the application of Corexit 9527 dispersant. In 1994 and 1995 the authors conducted a series of in situ toxicity bioassays in association with these spills with included 48h LC50 tests for turbot (Scophthalmus maximus) and oyster (Crassostrea gigas) larvae, a 48 h oyster (C. gigas) embryonic development test and two full life-cycle assays using the copepods Acartia tonsa and Tisbe battagliai. Tests were also conducted in the Chesapeake Bay laboratory using estuarine species including the copepod Eurytemora affinis and the inland silverside Menidia beryllina. Here, the authors report on the results of these assays, together with 1996 in situ toxicity data resulting from Norwegian field trials in the northern North Sea

  9. A roadmap for the development of alternative (non-animal) methods for systemic toxicity testing - t4 report*.

    Science.gov (United States)

    Basketter, David A; Clewell, Harvey; Kimber, Ian; Rossi, Annamaria; Blaauboer, Bas; Burrier, Robert; Daneshian, Mardas; Eskes, Chantra; Goldberg, Alan; Hasiwa, Nina; Hoffmann, Sebastian; Jaworska, Joanna; Knudsen, Thomas B; Landsiedel, Robert; Leist, Marcel; Locke, Paul; Maxwell, Gavin; McKim, James; McVey, Emily A; Ouédraogo, Gladys; Patlewicz, Grace; Pelkonen, Olavi; Roggen, Erwin; Rovida, Costanza; Ruhdel, Irmela; Schwarz, Michael; Schepky, Andreas; Schoeters, Greet; Skinner, Nigel; Trentz, Kerstin; Turner, Marian; Vanparys, Philippe; Yager, James; Zurlo, Joanne; Hartung, Thomas

    2012-01-01

    Systemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new products (such as nanoparticles or cell therapies), the limited predictivity of traditional tests for human health effects, duration and costs of current approaches, and animal welfare considerations. The latter holds especially true in the context of the scheduled 2013 marketing ban on cosmetic ingredients tested for systemic toxicity. Based on a major analysis of the status of alternative methods (Adler et al., 2011) and its independent review (Hartung et al., 2011), the present report proposes a roadmap for how to overcome the acknowledged scientific gaps for the full replacement of systemic toxicity testing using animals. Five whitepapers were commissioned addressing toxicokinetics, skin sensitization, repeated-dose toxicity, carcinogenicity, and reproductive toxicity testing. An expert workshop of 35 participants from Europe and the US discussed and refined these whitepapers, which were subsequently compiled to form the present report. By prioritizing the many options to move the field forward, the expert group hopes to advance regulatory science.

  10. TOXICITY TESTING IN THE 21ST CENTURY: A VISION AND A STRATEGY

    DEFF Research Database (Denmark)

    Krewski, D.; Acosta, D.; Andersen, M.

    2010-01-01

    With the release of the landmark report Toxicity Testing in the 21st Century: A Vision and a Strategy, the U. S. National Academy of Sciences, in 2007, precipitated a major change in the way toxicity testing is conducted. It envisions increased efficiency in toxicity testing and decreased animal ...

  11. Relationships Among Two Repeated Activity Tests and Aerobic Fitness of Volleyball Players.

    Science.gov (United States)

    Meckel, Yoav; May-Rom, Moran; Ekshtien, Aya; Eisenstein, Tamir; Nemet, Dan; Eliakim, Alon

    2015-08-01

    The purpose of the study was to determine performance indices of a repeated sprint test (RST) and to examine their relationships with performance indices of a repeated jump test (RJT) and with aerobic fitness among trained volleyball players. Sixteen male volleyball players performed RST (6 × 30 m sprints), RJT (6 sets of 6 consecutive jumps), and an aerobic power test (20-m Shuttle Run Test). Performance indices for the RST and the RJT were (a) the ideal 30-m run time (IS), the total run time (TS) of the 6 sprints, and the performance decrement (PD) during the test and (b) the ideal jump height (IJ), the total jump height (TJ) of all the jumps, and the PD during the test, respectively. No significant correlations were found between performance indices of the RST and RJT. Significant correlations were found between PD, IS, and TS in the RST protocol and predicted peak V[Combining Dot Above]O2 (r = -0.60, -0.75, -0.77, respectively). No significant correlations were found between performance indices of the RJT (IJ, TJ, and PD) and peak V[Combining Dot Above]O2. The findings suggest that a selection of repeated activity test protocols should acknowledge the specific technique used in the sport, and that a distinct RJT, rather than the classic RST, is more appropriate for assessing the anaerobic capabilities of volleyball players. The findings also suggest that aerobic fitness plays only a minor role in performance maintenance throughout characteristic repeated jumping activity of a volleyball game.

  12. Prediction of toxicity and comparison of alternatives using WebTEST (Web-services Toxicity Estimation Software Tool)

    Science.gov (United States)

    A Java-based web service is being developed within the US EPA’s Chemistry Dashboard to provide real time estimates of toxicity values and physical properties. WebTEST can generate toxicity predictions directly from a simple URL which includes the endpoint, QSAR method, and ...

  13. Non-animal methodologies within biomedical research and toxicity testing.

    Science.gov (United States)

    Knight, Andrew

    2008-01-01

    Laboratory animal models are limited by scientific constraints on human applicability, and increasing regulatory restrictions, driven by social concerns. Reliance on laboratory animals also incurs marked - and in some cases, prohibitive - logistical challenges, within high-throughput chemical testing programmes, such as those currently underway within Europe and the US. However, a range of non-animal methodologies is available within biomedical research and toxicity testing. These include: mechanisms to enhance the sharing and assessment of existing data prior to conducting further studies, and physicochemical evaluation and computerised modelling, including the use of structure-activity relationships and expert systems. Minimally-sentient animals from lower phylogenetic orders or early developmental vertebral stages may be used, as well as microorganisms and higher plants. A variety of tissue cultures, including immortalised cell lines, embryonic and adult stem cells, and organotypic cultures, are also available. In vitro assays utilising bacterial, yeast, protozoal, mammalian or human cell cultures exist for a wide range of toxic and other endpoints. These may be static or perfused, and may be used individually, or combined within test batteries. Human hepatocyte cultures and metabolic activation systems offer potential assessment of metabolite activity and organ-organ interaction. Microarray technology may allow genetic expression profiling, increasing the speed of toxin detection, well prior to more invasive endpoints. Enhanced human clinical trials utilising micro- dosing, staggered dosing, and more representative study populations and durations, as well as surrogate human tissues, advanced imaging modalities and human epidemiological, sociological and psycho- logical studies, may increase our understanding of illness aetiology and pathogenesis, and facilitate the development of safe and effective pharmacologic interventions. Particularly when human tissues

  14. Repeatability of an automated Landolt C test, compared with the early treatment of diabetic retinopathy study (ETDRS) chart testing.

    Science.gov (United States)

    Ruamviboonsuk, Paisan; Tiensuwan, Montip; Kunawut, Catleya; Masayaanon, Patcharapim

    2003-10-01

    To evaluate the repeatability of visual acuity scores from the automated test and compare them with the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. Instrument validation study based on a model of repeatability study in two observations. SMETHODS: a prospective, clinic-based, comparative study. A total of 206 participants without ocular diseases and refractive errors in their right eyes were randomly enrolled in the automated group in which 107 participants performed the automated test and the ETDRS group in which 99 participants read the ETDRS chart. All participants were tested with only their right eyes without corrections at 4 meters and came back to have the same tests 1 week later. The automated test used the Landolt rings as optotypes and was conducted by a low-ended personal computer with a 15-inch monitor and a wireless keyboard. The "letter" score calculated by counting every correct response to optotypes, and the "threshold curve" score interpreted from the optotype size at the midpoint of a visual acuity threshold curve. The 95% confidence interval of test-retest of visual acuity scores from the automated test are comparable to the ETDRS chart (.143 compared with.125 for letter scores,.145 compared with.122 for threshold curve scores). The score repeatabilities, calculated from the standard deviations of test-retest, from the automated test are also comparable to the ETDRS chart (.201 compared with.177 for letter scores,.206 compared with.172 for threshold curve scores). All comparisons demonstrated no statistical difference (P >.05). The automated testing system in this study enables practical measuring visual acuity by the Landolt rings. The system's repeatability, which is comparable to the ETDRS chart, supports its role as an alternative tool for measuring outcome in new clinical research. Its ability to practically generate visual acuity threshold curves may also be useful in future clinical research studies.

  15. Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment.

    Science.gov (United States)

    Chaudhari, Umesh; Nemade, Harshal; Wagh, Vilas; Gaspar, John Antonydas; Ellis, James K; Srinivasan, Sureshkumar Perumal; Spitkovski, Dimitry; Nguemo, Filomain; Louisse, Jochem; Bremer, Susanne; Hescheler, Jürgen; Keun, Hector C; Hengstler, Jan G; Sachinidis, Agapios

    2016-11-01

    The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the identification of predictive genomics biomarkers of functional relevance for drug-induced cardiotoxicity in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). The hiPSC-CMs were incubated with 156 nM doxorubicin, which is a well-characterized cardiotoxicant, for 2 or 6 days followed by washout of the test compound and further incubation in compound-free culture medium until day 14 after the onset of exposure. An xCELLigence Real-Time Cell Analyser was used to monitor doxorubicin-induced cytotoxicity while also monitoring functional alterations of cardiomyocytes by counting of the beating frequency of cardiomyocytes. Unlike single exposure, repeated doxorubicin exposure resulted in long-term arrhythmic beating in hiPSC-CMs accompanied by significant cytotoxicity. Global gene expression changes were studied using microarrays and bioinformatics tools. Analysis of the transcriptomic data revealed early expression signatures of genes involved in formation of sarcomeric structures, regulation of ion homeostasis and induction of apoptosis. Eighty-four significantly deregulated genes related to cardiac functions, stress and apoptosis were validated using real-time PCR. The expression of the 84 genes was further studied by real-time PCR in hiPSC-CMs incubated with daunorubicin and mitoxantrone, further anthracycline family members that are also known to induce cardiotoxicity. A panel of 35 genes was deregulated by all three anthracycline family members and can therefore be expected to predict the cardiotoxicity of compounds acting by similar mechanisms as doxorubicin, daunorubicin or mitoxantrone. The identified gene panel can be applied in the safety

  16. Hysteresis analysis of graphene transistor under repeated test and gate voltage stress

    International Nuclear Information System (INIS)

    Yang Jie; Jia Kunpeng; Su Yajuan; Zhao Chao; Chen Yang

    2014-01-01

    The current transport characteristic is studied systematically based on a back-gate graphene field effect transistor, under repeated test and gate voltage stress. The interface trapped charges caused by the gate voltage sweep process screens the gate electric field, and results in the neutral point voltage shift between the forth and back sweep direction. In the repeated test process, the neutral point voltage keeps increasing with test times in both forth and back sweeps, which indicates the existence of interface trapped electrons residual and accumulation. In gate voltage stress experiment, the relative neutral point voltage significantly decreases with the reducing of stress voltage, especially in −40 V, which illustrates the driven-out phenomenon of trapped electrons under negative voltage stress. (semiconductor devices)

  17. Study of Optimal Perimetric Testing in Children (OPTIC: Feasibility, Reliability and Repeatability of Perimetry in Children.

    Directory of Open Access Journals (Sweden)

    Dipesh E Patel

    Full Text Available To investigate feasibility, reliability and repeatability of perimetry in children.A prospective, observational study recruiting 154 children aged 5-15 years, without an ophthalmic condition that affects the visual field (controls, identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24-2 FAST, Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability.Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests. Examiner rated reliability was 'good' in 125 (81.2% children for Goldmann, 100 (64.9% for Octopus and 98 (63.6% for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey, p<0.001. No significant differences were found for any of the three test strategies when examining initial and follow-up data outputs (Bland-Altman plots, n=43, suggesting good test repeatability, although the sample size may preclude detection of a small learning effect.Feasibility and reliability of formal perimetry in children improves with age. By the age of 9 years, all the strategies used here were highly feasible and reliable. Clinical assessment of the visual field is achievable in children as young as 5 years, and should be considered where visual field loss is suspected. Since Goldmann perimetry is the most effective strategy in children aged 5-8 years and this perimeter is no longer available, further

  18. Repeat HIV testing during pregnancy and delivery: missed opportunities in a rural district hospital in Zambia.

    Science.gov (United States)

    Heemelaar, Steffie; Habets, Nicole; Makukula, Ziche; van Roosmalen, Jos; van den Akker, Thomas

    2015-03-01

    To assess coverage of repeat HIV testing among women who delivered in a Zambian hospital. HIV testing of pregnant women and repeat testing every 3 months during pregnancy and breastfeeding is the recommended policy in areas of high HIV prevalence. A prospective implementation study in a second-level hospital in rural Zambia. Included were all pregnant women who delivered in hospital during May and June 2012. Data regarding antenatal visits and HIV testing were collected by two investigators using a standardised form. Of 401 women who delivered in hospital, sufficient antenatal data could be retrieved for 322 (80.3%) women. Of these 322 women, 301 (93.5%) had attended antenatal care (ANC) at least once. At the time of discharge after delivery in hospital, 171 (53.1%) had an unclear HIV status because their negative test result was more than 3 months ago or of an unknown date, or because they had not been tested at all during pregnancy or delivery. An updated HIV status was present for 151 (46.9%) women: 25 (7.8%) were HIV positive and 126 (39.1%) had tested negative within the last 3 months. In this last group, 79 (24.5%) had been tested twice or more during pregnancy. During the study period, none of the women was tested during admission for delivery. Despite high ANC coverage, opportunities for repeat HIV testing were missed in almost half of all women who delivered in this hospital in a high-prevalence HIV setting. © 2014 John Wiley & Sons Ltd.

  19. In vitro pyrogen test for toxic or immunomodulatory drugs.

    Science.gov (United States)

    Daneshian, Mardas; Guenther, Armin; Wendel, Albrecht; Hartung, Thomas; von Aulock, Sonja

    2006-06-30

    Pyrogenic contaminations of some classes of injectable drugs, e.g. toxic or immunomodulatory as well as false-positive drugs, represent a major risk which cannot yet be excluded due to the limitations of current tests. Here we describe a modification of the In vitro Pyrogen Test termed AWIPT (Adsorb, Wash, In vitro Pyrogen Test), which addresses this problem by introducing a pre-incubation step in which pyrogenic contaminations in the test sample are adsorbed to albumin-coated beads. After rinsing, the beads are incubated with human whole blood and the release of the endogenous pyrogen interleukin-1beta is measured as a marker of pyrogenic activity. Intentional contaminations with lipopolysaccharide were retrieved from the chemotherapeutic agents paclitaxel, cisplatin and liposomal daunorubicin, the antibiotic gentamicin, the antifungal agent liposomal amphotericin B, and the corticosteroid prednisolone at lower dilutions than in the standard in vitro pyrogen test. This represents a promising new approach for the detection of pyrogenic contamination in drugs or in drugs containing interfering additives and should lead to improved safety levels.

  20. Repeated dose intramuscular injection of the CIMAvax-EGF vaccine in Sprague Dawley rats induces local and systemic toxicity.

    Science.gov (United States)

    Mancebo, A; Casacó, A; González, B; Ledón, N; Sorlozabal, J; León, A; Gómez, D; González, Y; Bada, A M; González, C; Arteaga, M E; Ramírez, H; Fuentes, D

    2012-05-09

    CIMAvax-EGF consists of a human recombinant epidermal growth factor (EGF), coupled to P64k, a recombinant carrier protein from N. meningitis, and Montanide ISA 51 as adjuvant. The vaccine immunization induces a specific antibody production, inhibiting the EGF/EGF-R interaction through EGF deprivation. The objective of this study was to assess the CIMAvax-EGF toxicity in Sprague Dawley rats after intramuscular administration of repeated doses (6 months) and at the same time to determine if rat is a relevant species for studying CIMAvax-EGF vaccine. Rats were randomly distributed into four groups: control, Montanide ISA 51, treated with 1× and 15× of human total dose of the antigen. Animals were immunized weekly during 9 weeks, plus 9 immunizations every 14 days. Rats were inspected daily for clinical signs. Body weight, food consumption, and rectal temperature were measured during the administration of doses. Blood samples were collected for hematological, serum biochemical determinations and EGF titles at the beginning, three months and at the end of experimentation. Gross necropsy and histological examination of tissues were performed on animals at the end of the assay. Vaccine provoked the apparition of antibodies against EGF in the rats, demonstrating rat species relevance in these studies. Body weight gain, food and water consumption were not affected. CIMAvax-EGF and Montanide ISA 51 produced local damage at the administration site, showing multiple cysts and granulomas. Both vaccine-treated groups showed neutrophil elevation, besides an AST increase probably related to the damage at the administration site. Rectal temperature was found to be significantly higher in 15× treated group after immunizations, probably induced by the inflammatory process at the injection site. In summary, the clinical pathology findings together with the body temperature results, appear to be caused by the inflammatory reaction at the administration site of the vaccine, mainly

  1. Role of omics techniques in the toxicity testing of nanoparticles

    Directory of Open Access Journals (Sweden)

    Eleonore Fröhlich

    2017-11-01

    Full Text Available Abstract Nanotechnology is regarded as a key technology of the twenty-first century. Despite the many advantages of nanotechnology it is also known that engineered nanoparticles (NPs may cause adverse health effects in humans. Reports on toxic effects of NPs relay mainly on conventional (phenotypic testing but studies of changes in epigenome, transcriptome, proteome, and metabolome induced by NPs have also been performed. NPs most relevant for human exposure in consumer, health and food products are metal, metal oxide and carbon-based NPs. They were also studied quite frequently with omics technologies and an overview of the study results can serve to answer the question if screening for established targets of nanotoxicity (e.g. cell death, proliferation, oxidative stress, and inflammation is sufficient or if omics techniques are needed to reveal new targets. Regulated pathways identified by omics techniques were confirmed by phenotypic assays performed in the same study and comparison of particle types and cells by the same group indicated a more cell/organ-specific than particle specific regulation pattern. Between different studies moderate overlap of the regulated pathways was observed and cell-specific regulation is less obvious. The lack of standardization in particle exposure, in omics technologies, difficulties to translate mechanistic data to phenotypes and comparison with human in vivo data currently limit the use of these technologies in the prediction of toxic effects by NPs.

  2. A maximal cycle test with good validity and high repeatability in adults of all ages

    DEFF Research Database (Denmark)

    Eriksen, L; Tolstrup, J S; Larsen, Steen

    2014-01-01

    indirectly in both tests and measured directly in one test. Agreement between the direct measurement and the indirect estimate of VO2max and repeatability of the indirect estimates of VO2max were examined by Bland-Altman plots, limits of agreement (LOA) and coefficient of repeatability (CR). The indirect...... method (mean VO2max=3 132 ml · min(-1)) underestimated VO2max as compared to the direct method (mean VO2max=3 190 ml · min(-1)) in men (bias: 58 ml · min(-1) (95% LOA-450 and 565)) and overestimated VO2max in women (mean VO2max=2 328 vs. 2 258 ml · min(-1), bias: - 70 ml · min(-1) (95% LOA-468 and 328...

  3. Implementation of repeat HIV testing during pregnancy in Kenya: a qualitative study.

    Science.gov (United States)

    Rogers, Anna Joy; Weke, Elly; Kwena, Zachary; Bukusi, Elizabeth A; Oyaro, Patrick; Cohen, Craig R; Turan, Janet M

    2016-07-11

    Repeat HIV testing in late pregnancy has the potential to decrease rates of mother-to-child transmission of HIV by identifying mothers who seroconvert after having tested negative for HIV in early pregnancy. Despite being national policy in Kenya, the available data suggest that implementation rates are low. We conducted 20 in-depth semi-structured interviews with healthcare providers and managers to explore barriers and enablers to implementation of repeat HIV testing guidelines for pregnant women. Participants were from the Nyanza region of Kenya and were purposively selected to provide variation in socio-demographics and job characteristics. Interview transcripts were coded and analyzed in Dedoose software using a thematic analysis approach. Four themes were identified a priori using Ferlie and Shortell's Framework for Change and additional themes were allowed to emerge from the data. Participants identified barriers and enablers at the client, provider, facility, and health system levels. Key barriers at the client level from the perspective of providers included late initial presentation to antenatal care and low proportions of women completing the recommended four antenatal visits. Barriers to offering repeat HIV testing for providers included heavy workloads, time limitations, and failing to remember to check for retest eligibility. At the facility level, inconsistent volume of clients and lack of space required for confidential HIV retesting were cited as barriers. Finally, at the health system level, there were challenges relating to the HIV test kit supply chain and the design of nationally standardized antenatal patient registers. Enablers to improving the implementation of repeat HIV testing included client dissemination of the benefits of antenatal care through word-of-mouth, provider cooperation and task shifting, and it was suggested that use of an electronic health record system could provide automatic reminders for retest eligibility. This study

  4. Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

    Directory of Open Access Journals (Sweden)

    Amin Daneshfar

    2018-04-01

    Full Text Available The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m multi-directional repeated sprint ability test (RSM in elite young team handball (TH players. Participants were members of the Iranian national team (n = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%. The validity of RSM was tested against a 10 × (15 + 15 m repeated sprint ability test (RSA, Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1, squat jump (SJ and countermovement jump (CMJ. To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT, best time (BT, and weakest time (WT. The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA (r = −0.57, p ≤ 0.05 and RSM (r = −0.76, p ≤ 0.01. There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI in RSA test (r = −0.64, p ≤ 0.01 and in RSM test (r = −0.53, p ≤ 0.05. BT, WT, and TT of RSA was largely-to-very largely correlated with BT (r = 0.58, p ≤ 0.01, WT (r = 0.62, p ≤ 0.01, and TT (r = 0.65, p ≤ 0.01 of RSM. BT in RSM was also correlated with FI in RSM (r = 0.88, p ≤ 0.01. In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players.

  5. Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

    Science.gov (United States)

    Daneshfar, Amin; Gahreman, Daniel E.; Koozehchian, Majid S.; Amani Shalamzari, Sadegh; Hassanzadeh Sablouei, Mozhgan; Rosemann, Thomas; Knechtle, Beat; Nikolaidis, Pantelis T.

    2018-01-01

    The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m) multi-directional repeated sprint ability test (RSM) in elite young team handball (TH) players. Participants were members of the Iranian national team (n = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%). The validity of RSM was tested against a 10 × (15 + 15 m) repeated sprint ability test (RSA), Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1), squat jump (SJ) and countermovement jump (CMJ). To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT), best time (BT), and weakest time (WT). The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA (r = −0.57, p ≤ 0.05) and RSM (r = −0.76, p ≤ 0.01). There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI) in RSA test (r = −0.64, p ≤ 0.01) and in RSM test (r = −0.53, p ≤ 0.05). BT, WT, and TT of RSA was largely-to-very largely correlated with BT (r = 0.58, p ≤ 0.01), WT (r = 0.62, p ≤ 0.01), and TT (r = 0.65, p ≤ 0.01) of RSM. BT in RSM was also correlated with FI in RSM (r = 0.88, p ≤ 0.01). In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players. PMID:29670536

  6. Acute Toxicity Tests Of Brewery Effluent on the Ostracoda ...

    African Journals Online (AJOL)

    Mortality also varied with the concentrations. The toxic effect of brewery effluent on ostracoda, which plays an important role in the aquatic food chain and the possibility that they may be accumulating some of these toxic components, is a matter for concern. Keywords: Toxicity, rewery effluent, Ostracoda, Strandesia, ...

  7. Discovering less toxic ionic liquids by using the Microtox® toxicity test.

    Science.gov (United States)

    Hernández-Fernández, F J; Bayo, J; Pérez de los Ríos, A; Vicente, M A; Bernal, F J; Quesada-Medina, J

    2015-06-01

    New Microtox® toxicity data of 16 ionic liquids of different cationic and anionic composition were determined. The ionic liquids 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate, [BMPyr(+)][TFO(-)], 1-butyl-1-methylpyrrolidinium chloride, [BMPyr(+)][Cl(-)], hydroxypropylmethylimidazolium fluoroacetate, [HOPMIM(+)][FCH2COO(-)], and hydroxypropylmethylimidazolium glycolate [HOPMIM(+)][glycolate(-)] were found to be less toxic than conventional organic solvent such as chloroform or toluene, accoding the Microtox® toxicity assays. The toxicity of pyrrolidinium cation was lower than the imidazolium and pyridinium ones. It was found that the inclusion of an hydroxyl group in the alkyl chain length of the cation also reduce the toxicity of the ionic liquid. To sum up, the Microtox® toxicity assays can be used as screening tool to easily determined the toxicity of a wide range of ionic liquids and the toxicity data obtained could allow the obtention of structure-toxicity relationships to design less toxic ionic liquids. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Toxicity testing of polymer materials for dialysis equipment: reconsidering in vivo testing.

    Science.gov (United States)

    Sauer, U G; Liebsch, M; Kolar, R

    2000-01-01

    In fulfilment of the aims of the European Union Biocidal Directive (Directive 98/8/EC), Technical Guidance Documents are currently being compiled. Part I of these Technical Guidance Documents covers data requirements for active substances and biocidal products. The Three Rs principle has been applied in certain parts of the toxicity and ecotoxicity testing scheme for pesticides, such as testing for acute oral toxicity, skin and eye irritation, skin sensitisation, and dermal absorption. Further recommendations on how to proceed with regard to the continuing replacement, reduction and refinement of animal experiments in this field of regulatory testing are included for consideration. In this context, besides stressing the necessity to validate and accept further alternatives, emphasis is placed on providing the possibility of waiving unnecessary tests and on the continuous evaluation of whether certain tests are needed at all. 2000 FRAME.

  9. Effects of Repeated Testing on Short- and Long-Term Memory Performance across Different Test Formats

    Science.gov (United States)

    Stenlund, Tova; Sundström, Anna; Jonsson, Bert

    2016-01-01

    This study examined whether practice testing with short-answer (SA) items benefits learning over time compared to practice testing with multiple-choice (MC) items, and rereading the material. More specifically, the aim was to test the hypotheses of "retrieval effort" and "transfer appropriate processing" by comparing retention…

  10. A 90-day repeated-dose toxicity study of dietary alpha linolenic acid-enriched diacylglycerol oil in rats.

    Science.gov (United States)

    Bushita, Hiroto; Ito, Yuichi; Saito, Tetsuji; Nukada, Yuko; Ikeda, Naohiro; Nakagiri, Hideaki; Saito, Kazutoshi; Morita, Osamu

    2018-05-31

    Diets supplemented with alpha-linolenic acid (ALA)-enriched diacylglycerol (DAG) oil-which mainly consists of oleic and linolenic, linoleic acids-have potential health benefits in terms of preventing or managing obesity. Although safety of DAG oil has been extensively investigated, toxicity of ALA-DAG oil has not been well understood. Hence, the present study was conducted to clarify the potential adverse effects, if any, of ALA-DAG oil in rats (10/sex/group) fed diets containing 1.375%, 2.75%, or 5.5% ALA-DAG oil for 90 days. Compared to control rats fed rapeseed oil or ALA-triacylglycerol oil (flaxseed oil), rats receiving ALA-DAG oil did not reveal any toxicologically significant treatment-related changes as evaluated by clinical signs, functional observational battery, body weight, food consumption, ophthalmology, urinalysis, hematology, clinical chemistry, organ weight, necropsy and histopathology. The no observed adverse effect levels for dietary exposure to ALA-DAG oil for male and female rats were 2916 and 3326 mg/kg body weight/day, respectively, the highest dose tested. The findings from this study suggest that consumption of ALA-DAG oil is unlikely to cause adverse effects. Copyright © 2018. Published by Elsevier Inc.

  11. Towards sensible toxicity testing for nanomaterials: proposal for the specification of test design

    International Nuclear Information System (INIS)

    Potthoff, Annegret; Meißner, Tobias; Weil, Mirco; Kühnel, Dana

    2015-01-01

    During the last decade, nanomaterials (NM) were extensively tested for potential harmful effects towards humans and environmental organisms. However, a sound hazard assessment was so far hampered by uncertainties and a low comparability of test results. The reason for the low comparability is a high variation in the (1) type of NM tested with regard to raw material, size and shape and (2) procedures before and during the toxicity testing. This calls for tailored, nanomaterial-specific protocols. Here, a structured approach is proposed, intended to lead to test protocols not only tailored to specific types of nanomaterials, but also to respective test system for toxicity testing. There are existing standards on single procedures involving nanomaterials, however, not all relevant procedures are covered by standards. Hence, our approach offers a detailed way of weighting several plausible alternatives for e.g. sample preparation, in order to decide on the procedure most meaningful for a specific nanomaterial and toxicity test. A framework of several decision trees (DT) and flow charts to support testing of NM is proposed as a basis for further refinement and in-depth elaboration. DT and flow charts were drafted for (1) general procedure—physicochemical characterisation, (2) choice of test media, (3) decision on test scenario and application of NM to liquid media, (4) application of NM to the gas phase, (5) application of NM to soil and sediments, (6) dose metrics, (S1) definition of a nanomaterial, and (S2) dissolution. The applicability of the proposed approach was surveyed by using experimental data retrieved from studies on nanoscale CuO. This survey demonstrated the DT and flow charts to be a convenient tool to systematically decide upon test procedures and processes, and hence pose an important step towards harmonisation of NM testing. (paper)

  12. Toxicity testing: the search for an in vitro alternative to animal testing.

    Science.gov (United States)

    May, J E; Xu, J; Morse, H R; Avent, N D; Donaldson, C

    2009-01-01

    Prior to introduction to the clinic, pharmaceuticals must undergo rigorous toxicity testing to ensure their safety. Traditionally, this has been achieved using in vivo animal models. However, besides ethical reasons, there is a continual drive to reduce the number of animals used for this purpose due to concerns such as the lack of concordance seen between animal models and toxic effects in humans. Adequate testing to ensure any toxic metabolites are detected can be further complicated if the agent is administered in a prodrug form, requiring a source of cytochrome P450 enzymes for metabolism. A number of sources of metabolic enzymes have been utilised in in vitro models, including cell lines, primary human tissue and liver extracts such as S9. This review examines current and new in vitro models for toxicity testing, including a new model developed within the authors' laboratory utilising HepG2 liver spheroids within a co-culture system to examine the effects of chemotherapeutic agents on other cell types.

  13. A Modified Jonckheere Test Statistic for Ordered Alternatives in Repeated Measures Design

    Directory of Open Access Journals (Sweden)

    Hatice Tül Kübra AKDUR

    2016-09-01

    Full Text Available In this article, a new test based on Jonckheere test [1] for  randomized blocks which have dependent observations within block is presented. A weighted sum for each block statistic rather than the unweighted sum proposed by Jonckheereis included. For Jonckheere type statistics, the main assumption is independency of observations within block. In the case of repeated measures design, the assumption of independence is violated. The weighted Jonckheere type statistic for the situation of dependence for different variance-covariance structure and the situation based on ordered alternative hypothesis structure of each block on the design is used. Also, the proposed statistic is compared to the existing test based on Jonckheere in terms of type I error rates by performing Monte Carlo simulation. For the strong correlations, circular bootstrap version of the proposed Jonckheere test provides lower rates of type I error.

  14. Remaining life assessment of carbon steel boiler headers by repeated creep testing

    Energy Technology Data Exchange (ETDEWEB)

    Drew, M. [ANSTO, Materials and Engineering Science, New Illawarra Road, Lucas Heights, PMB 1 Menai, NSW 2234 (Australia)]. E-mail: michael.drew@ansto.gov.au; Humphries, S. [ANSTO, Materials and Engineering Science, New Illawarra Road, Lucas Heights, PMB 1 Menai, NSW 2234 (Australia); Thorogood, K. [ANSTO, Materials and Engineering Science, New Illawarra Road, Lucas Heights, PMB 1 Menai, NSW 2234 (Australia); Barnett, N. [BlueScope Steel, P.O. Box 1854, Wollongong, NSW (Australia)

    2006-05-15

    The condition of carbon steel boiler headers that have been in service for over 25 years has been assessed periodically by NDT, dimensional measurements, replication and accelerated creep testing. Historical temperature records were limited, so estimates of effective header temperatures were made from replicas. These estimates were compared with header stub thermocouple readings. At about 280,000 service hours, samples were chain-drilled from the headers for accelerated creep testing. These test results indicated that the headers had satisfactory remaining life. Nine years after the original samples were taken, additional samples were removed from one header at 337,000 service hours. The creep rupture properties measured from the repeated tests were almost identical to the initial results. A mild degree of random, nodular graphite was found in the samples and its effect on creep properties is discussed.

  15. Integrated testing strategies for toxicity employing new and existing technologies.

    Science.gov (United States)

    Combes, Robert D; Balls, Michael

    2011-07-01

    We have developed individual, integrated testing strategies (ITS) for predicting the toxicity of general chemicals, cosmetics, pharmaceuticals, inhaled chemicals, and nanoparticles. These ITS are based on published schemes developed previously for the risk assessment of chemicals to fulfil the requirements of REACH, which have been updated to take account of the latest developments in advanced in chemico modelling and in vitro technologies. In addition, we propose an ITS for neurotoxicity, based on the same principles, for incorporation in the other ITS. The technologies are deployed in a step-wise manner, as a basis for decision-tree approaches, incorporating weight-of-evidence stages. This means that testing can be stopped at the point where a risk assessment and/or classification can be performed, with labelling in accordance with the requirements of the regulatory authority concerned, rather than following a checklist approach to hazard identification. In addition, the strategies are intelligent, in that they are based on the fundamental premise that there is no hazard in the absence of exposure - which is why pharmacokinetic modelling plays a key role in each ITS. The new technologies include the use of complex, three-dimensional human cell tissue culture systems with in vivo-like structural, physiological and biochemical features, as well as dosing conditions. In this way, problems of inter-species extrapolation and in vitro/in vivo extrapolation are minimised. This is reflected in the ITS placing more emphasis on the use of volunteers at the whole organism testing stage, rather than on existing animal testing, which is the current situation. 2011 FRAME.

  16. Effects of repeated asenapine in a battery of tests for anxiety-like behaviours in mice.

    Science.gov (United States)

    Ene, Hila M; Kara, Nirit Z; Barak, Noa; Reshef Ben-Mordechai, Tal; Einat, Haim

    2016-04-01

    A number of atypical antipsychotic drugs were demonstrated to have anxiolytic effects in patients and in animal models. These effects were mostly suggested to be the consequence of the drugs' affinity to the serotonin system and its receptors. Asenapine is a relatively new atypical antipsychotic that is prescribed for schizophrenia and for bipolar mania. Asenapine has a broad pharmacological profile with significant effects on serotonergic receptors, hence it is reasonable to expect that asenapine may have some anxiolytic effects. The present study was therefore designed to examine possible effects of asenapine on anxiety-like behaviour of mice. Male ICR mice were repeatedly treated with 0.1 or 0.3 mg/kg injections of asenapine and then tested in a battery of behavioural tests related to anxiety including the open-field test, elevated plus-maze (EPM), defensive marble burying and hyponeophagia tests. In an adjunct experiment, we tested the effects of acute diazepam in the same test battery. The results show that diazepam reduced anxiety-like behaviour in the EPM, the defensive marble burying test and the hyponeophagia test but not in the open field. Asenapine has anxiolytic-like effects in the EPM and the defensive marble burying tests but had no effects in the open-field or the hyponeophagia tests. Asenapine had no effects on locomotor activity. The results suggest that asenapine may have anxiolytic-like properties and recommends that clinical trials examining such effects should be performed.

  17. Is the OECD acute worm toxicity test environmentally relevant? The effect of mineral form on calculated lead toxicity

    International Nuclear Information System (INIS)

    Davies, N.A.Nicola A.; Hodson, M.E.Mark E.; Black, S.Stuart

    2003-01-01

    The current OECD acute worm toxicity test does not relate well to ambient conditions. - In a series of experiments the toxicity of lead to worms in soil was determined following the draft OECD earthworm reproduction toxicity protocol except that lead was added as solid lead nitrate, carbonate and sulphide rather than as lead nitrate solution as would normally be the case. The compounds were added to the test soil to give lead concentrations of 625-12500 μg Pb g -1 of soil. Calculated toxicities of the lead decreased in the order nitrate>carbonate>sulphide, the same order as the decrease in the solubility of the metal compounds used. The 7-day LC 50 (lethal concentration when 50% of the population is killed) for the nitrate was 5321±275 μg Pb g -1 of soil and this did not change with time. The LC 50 values for carbonate and sulphide could not be determined at the concentration ranges used. The only parameter sensitive enough to distinguish the toxicities of the three compounds was cocoon (egg) production. The EC 50 s for cocoon production (the concentration to produce a 50% reduction in cocoon production) were 993, 8604 and 10246 μg Pb g -1 of soil for lead nitrate, carbonate and sulphide, respectively. Standard toxicity tests need to take into account the form in which the contaminant is present in the soil to be of environmental relevance

  18. The Glycine-Alanine Dipeptide Repeat from C9orf72 Hexanucleotide Expansions Forms Toxic Amyloids Possessing Cell-to-Cell Transmission Properties.

    Science.gov (United States)

    Chang, Yu-Jen; Jeng, U-Ser; Chiang, Ya-Ling; Hwang, Ing-Shouh; Chen, Yun-Ru

    2016-03-04

    Hexanucleotide expansions, GGGGCC, in the non-coding regions of the C9orf72 gene were found in major frontotemporal lobar dementia and amyotrophic lateral sclerosis patients (C9FTD/ALS). In addition to possible RNA toxicity, several dipeptide repeats (DPRs) are translated through repeat-associated non-ATG-initiated translation. The DPRs, including poly(GA), poly(GR), poly(GP), poly(PR), and poly(PA), were found in the brains and spinal cords of C9FTD/ALS patients. Among the DPRs, poly(GA) is highly susceptible to form cytoplasmic inclusions, which is a characteristic of C9FTD/ALS. To elucidate DPR aggregation, we used synthetic (GA)15 DPR as a model system to examine the aggregation and structural properties in vitro. We found that (GA)15 with 15 repeats fibrillates rapidly and ultimately forms flat, ribbon-type fibrils evidenced by transmission electron microscopy and atomic force microscopy. The fibrils are capable of amyloid dye binding and contain a characteristic cross-β sheet structure, as revealed by x-ray scattering. Furthermore, using neuroblastoma cells, we demonstrated the neurotoxicity and cell-to-cell transmission property of (GA)15 DPR. Overall, our results show the structural and toxicity properties of GA DPR to facilitate future DPR-related therapeutic development. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Diffusion-weighted (DW) MRI in lung cancers. ADC test-retest repeatability

    Energy Technology Data Exchange (ETDEWEB)

    Weller, Alex; Papoutsaki, Marianthi Vasiliki; Blackledge, Matthew; DeSouza, Nandita M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, CRUK Cancer Imaging Centre, Surrey (United Kingdom); Waterton, John C. [University of Manchester, Manchester (United Kingdom); Chiti, Arturo [Humanitas University, Milan (Italy); Stroobants, Sigrid [Universiteit Antwerpen, Antwerpen (Belgium); Kuijer, Joost [Vrije Universiteit Medisch Centrum, Amsterdam (Netherlands); Morgan, Veronica [Royal Marsden NHS Foundation Trust, Department of Medicine, London (United Kingdom)

    2017-11-15

    To determine the test-retest repeatability of Apparent Diffusion Coefficient (ADC) measurements across institutions and MRI vendors, plus investigate the effect of post-processing methodology on measurement precision. Thirty malignant lung lesions >2 cm in size (23 patients) were scanned on two occasions, using echo-planar-Diffusion-Weighted (DW)-MRI to derive whole-tumour ADC (b = 100, 500 and 800 s/mm{sup -2}). Scanning was performed at 4 institutions (3 MRI vendors). Whole-tumour volumes-of-interest were copied from first visit onto second visit images and from one post-processing platform to an open-source platform, to assess ADC repeatability and cross-platform reproducibility. Whole-tumour ADC values ranged from 0.66-1.94x10{sup -3} mm{sup 2}s{sup -1} (mean = 1.14). Within-patient coefficient-of-variation (wCV) was 7.1% (95% CI 5.7-9.6%), limits-of-agreement (LoA) -18.0 to 21.9%. Lesions >3 cm had improved repeatability: wCV 3.9% (95% CI 2.9-5.9%); and LoA -10.2 to 11.4%. Variability for lesions <3 cm was 2.46 times higher. ADC reproducibility across different post-processing platforms was excellent: Pearson's R{sup 2} = 0.99; CoV 2.8% (95% CI 2.3-3.4%); and LoA -7.4 to 8.0%. A free-breathing DW-MRI protocol for imaging malignant lung tumours achieved satisfactory within-patient repeatability and was robust to changes in post-processing software, justifying its use in multi-centre trials. For response evaluation in individual patients, a change in ADC >21.9% will reflect treatment-related change. (orig.)

  20. Cost-effectiveness of a repeat HIV test in pregnancy in India.

    Science.gov (United States)

    Joshi, Smita; Kulkarni, Vinay; Gangakhedkar, Raman; Mahajan, Uma; Sharma, Sushma; Shirole, Devendra; Chandhiok, Nomita

    2015-06-11

    To evaluate cost-effectiveness of second HIV test in pregnancy. Current strategy of single HIV test during pregnancy in India can miss new HIV infections acquired after the first test or those HIV infections that were missed in the first test due to a false-negative HIV test. Between August 2011 and April 2013, 9097 pregnant HIV uninfected women were offered a second HIV test near term (34 weeks or beyond) or within 4 weeks of postpartum period. A decision analysis model was used to evaluate cost-effectiveness of a second HIV test in pregnant women near term. Our key outcome measures include programme cost with addition of second HIV test in pregnant women and quality-adjusted life years (QALYs) gained. We detected 4 new HIV infections in the second test. Thus HIV incidence among pregnant women was 0.12 (95% 0.032 to 0.297) per 100 person women years (PWY). Current strategy of a single HIV test is 8.2 times costlier for less QALYs gained as compared to proposed repeat HIV testing of pregnant women who test negative during the first test. Our results warrant consideration at the national level for including a second HIV test of all pregnant women in the national programme. However prior to allocation of resources for a second HIV test in pregnancy, appropriate strategies will have to be planned for improving compliance for prevention of mother-to-child transmission of HIV and reducing loss-to-follow-up of those women detected with HIV. CTRI/2013/12/004183. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Early Evolution of the Toxicity Identification Evaluation Process: Contributions from the USEPA Effluent Testing Program

    Science.gov (United States)

    As part of its whole effluent testing program, the USEPA developed an effects-directed analysis (EDA) approach to identifying the cause of toxicity in toxic effluents or ambient waters, an EDA process termed a “Toxicity Identification Evaluation” (TIE), which is the focus of this...

  2. Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification.

    Directory of Open Access Journals (Sweden)

    Bonita J Brewer

    2015-12-01

    Full Text Available DNA replication errors are a major driver of evolution--from single nucleotide polymorphisms to large-scale copy number variations (CNVs. Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model--Origin-Dependent Inverted-Repeat Amplification (ODIRA-proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error-the ligation of leading and lagging nascent strands to create "closed" forks-can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent--a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins

  3. Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification.

    Science.gov (United States)

    Brewer, Bonita J; Payen, Celia; Di Rienzi, Sara C; Higgins, Megan M; Ong, Giang; Dunham, Maitreya J; Raghuraman, M K

    2015-12-01

    DNA replication errors are a major driver of evolution--from single nucleotide polymorphisms to large-scale copy number variations (CNVs). Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model--Origin-Dependent Inverted-Repeat Amplification (ODIRA)-proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error-the ligation of leading and lagging nascent strands to create "closed" forks-can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent--a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins of interstitial

  4. Can interpreting sediment toxicity tests a mega sites benefit from novel approaches to normalization to address batching of tests?

    Science.gov (United States)

    Sediment toxicity tests are a key tool used in Ecological Risk Assessments for contaminated sediment sites. Interpreting test results and defining toxicity is often a challenge. This is particularly true at mega sites where the testing regime is large, and by necessity performed ...

  5. Parenting, attention and externalizing problems: testing mediation longitudinally, repeatedly and reciprocally.

    Science.gov (United States)

    Belsky, Jay; Pasco Fearon, R M; Bell, Brian

    2007-12-01

    Building on prior work, this paper tests, longitudinally and repeatedly, the proposition that attentional control processes mediate the effect of earlier parenting on later externalizing problems. Repeated independent measurements of all three constructs--observed parenting, computer-tested attentional control and adult-reported externalizing problems--were subjected to structural equation modeling using data from the large-scale American study of child care and youth development. Structural equation modeling indicated (a) that greater maternal sensitivity at two different ages (54 months, approximately 6 years) predicted better attentional control on the Continuous Performance Test (CPT) of attention regulation two later ages ( approximately 6/9 years); (2) that better attentional control at three different ages (54 months, approximately 6/9 years) predicted less teacher-reported externalizing problems at three later ages ( approximately 6/8/10 years); and (3) that attentional control partially mediated the effect of parenting on externalizing problems at two different lags (i.e., 54 months--> approximately 6 years--> approximately 8 years; approximately 6 years--> approximately 9 years--> approximately 10 years), though somewhat more strongly for the first. Additionally, (4) some evidence of reciprocal effects of attentional processes on parenting emerged (54 months--> approximately 6 years; approximately 6 years--> approximately 8 years), but not of problem behavior on attention. Because attention control partially mediates the effects of parenting on externalizing problems, intervention efforts could target both parenting and attentional processes.

  6. Handling nonnormality and variance heterogeneity for quantitative sublethal toxicity tests.

    Science.gov (United States)

    Ritz, Christian; Van der Vliet, Leana

    2009-09-01

    The advantages of using regression-based techniques to derive endpoints from environmental toxicity data are clear, and slowly, this superior analytical technique is gaining acceptance. As use of regression-based analysis becomes more widespread, some of the associated nuances and potential problems come into sharper focus. Looking at data sets that cover a broad spectrum of standard test species, we noticed that some model fits to data failed to meet two key assumptions-variance homogeneity and normality-that are necessary for correct statistical analysis via regression-based techniques. Failure to meet these assumptions often is caused by reduced variance at the concentrations showing severe adverse effects. Although commonly used with linear regression analysis, transformation of the response variable only is not appropriate when fitting data using nonlinear regression techniques. Through analysis of sample data sets, including Lemna minor, Eisenia andrei (terrestrial earthworm), and algae, we show that both the so-called Box-Cox transformation and use of the Poisson distribution can help to correct variance heterogeneity and nonnormality and so allow nonlinear regression analysis to be implemented. Both the Box-Cox transformation and the Poisson distribution can be readily implemented into existing protocols for statistical analysis. By correcting for nonnormality and variance heterogeneity, these two statistical tools can be used to encourage the transition to regression-based analysis and the depreciation of less-desirable and less-flexible analytical techniques, such as linear interpolation.

  7. Feasibility and repeatability of cold and mechanical quantitative sensory testing in normal dogs

    Science.gov (United States)

    Briley, Jessica D.; Williams, Morika D.; Freire, Mila; Griffith, Emily H.; Lascelles, B. Duncan X.

    2015-01-01

    Feasibility and inter-session repeatability of cold and mechanical quantitative sensory testing (QST) were assessed in 24 normal dogs. Cold thermal latencies were evaluated using a thermal probe (0 °C) applied to three pelvic limb sites. Mechanical thresholds were measured using an electronic von Frey anesthesiometer (EVF) and a blunt-probed pressure algometer (PA) applied to the dorsal aspect of the metatarsus. All QST trials were performed with dogs in lateral recumbency. Collection of cold QST data was easy (feasible) in 19/24 (79%) dogs. However, only 18.4%, 18.9% and 13.2% of cold QST trials elicited a response at the medial tibia, third digital pad and plantar metatarsal regions, respectively. Collection of mechanical QST data was easy (feasible) in 20/24 (83%) dogs for both EVF and PA. At consecutive sampling times, approximately 2 weeks apart, the average EVF sensory thresholds were 414 ± 186 g and 379 ± 166 g, respectively, and the average PA sensory thresholds were 1089 ± 414 g and 1028 ± 331 g, respectively. There was no significant difference in inter-session or inter-limb threshold values for either mechanical QST device. The cold QST protocol in this study was achievable, but did not provide consistently quantifiable results. Both mechanical QST devices tested provided repeatable, reliable sensory threshold measurements in normal, client-owned dogs. These findings contribute to the validation of the EVF and PA as tools to obtain repeated QST data over time in dogs to assess somatosensory processing changes. PMID:24268475

  8. 40 CFR 799.9355 - TSCA reproduction/developmental toxicity screening test.

    Science.gov (United States)

    2010-07-01

    ... developmental defects should not be used. Healthy virgin animals, not subjected to previous experimental..., except legal holidays. (1) OECD (1995). Reproduction/Developmental Toxicity Screening Test, OECD 421...

  9. Protective effect of zinc over lead toxicity on testes

    International Nuclear Information System (INIS)

    Rafique, M.; Shaikh, S.P.; Tahir, F.

    2010-01-01

    To determine the effects of lead and zinc on testes. Study Design: Randomized control trial. Place and Duration of Study: Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi, from August 2003 to December 2005. Methodology: Sixty adult (90 days old) albino rats were obtained from animal house JPMC for the study and divided into 3 groups. Group A received injection normal saline 1 cc intraperitoneally daily for 8 weeks. Group B received lead chloride in a dose of 10 mg/kg body weight intraperitoneally daily. Group C received zinc chloride in a dose of 1 mg/kg body weight before half an hour of injection of lead chloride in a dose of 10 mg/kg body weight intraperitoneally daily so that to provide pre-treatment. On the day of completion of treatment the animals were sacrificed testes removed and fixed in Bouin's fluid. Testes were dehydrated in the ascending strength of alcohol, 5 mu m thick sections were cut and stained with PAS Iron Hematoxylin. Student's t-test was used for statistical analysis with significance at p < 0.05. Results: The mean diameter of seminiferous tubule was 291.91+-1.18, 198.53 +- 1.67 and 288.77 +- 1.11 mu m in groups A, B and C respectively. Diameter of seminiferous tubules decreased by 31.99% in group B (p < 0.001; CI 89.023 to 97.736) as compared group A and while group B comparing with group C, the diameter of seminiferous tubules was decreased by 31.25% (p-value = 0.076; CI -94.264 to -86.203). Mean thickness of germinal epithelium was 96.19 +- 1.01, 50.69 +- 1.20 and 94.94 +- 0.54 mu m in groups A, B and C respectively. Thickness of germinal epithelium decreased by 47.30 in group B (P < 0.001; CI 42.503 to 48.496) as compared to group A and while comparing group B with group C, the thickness of germinal epithelium was decreased by 46.61% (p=-44.25; CI -46.704 to -41.787). Conclusion: Zinc prevented toxic effects of lead on germinal epithelium in the albino rats. (author)

  10. The most prevalent genetic cause of ALS-FTD, C9orf72 synergizes the toxicity of ATXN2 intermediate polyglutamine repeats through the autophagy pathway.

    Science.gov (United States)

    Ciura, Sorana; Sellier, Chantal; Campanari, Maria-Letizia; Charlet-Berguerand, Nicolas; Kabashi, Edor

    2016-08-02

    The most common genetic cause for amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD) is repeat expansion of a hexanucleotide sequence (GGGGCC) within the C9orf72 genomic sequence. To elucidate the functional role of C9orf72 in disease pathogenesis, we identified certain molecular interactors of this factor. We determined that C9orf72 exists in a complex with SMCR8 and WDR41 and that this complex acts as a GDP/GTP exchange factor for RAB8 and RAB39, 2 RAB GTPases involved in macroautophagy/autophagy. Consequently, C9orf72 depletion in neuronal cultures leads to accumulation of unresolved aggregates of SQSTM1/p62 and phosphorylated TARDBP/TDP-43. However, C9orf72 reduction does not lead to major neuronal toxicity, suggesting that a second stress may be required to induce neuronal cell death. An intermediate size of polyglutamine repeats within ATXN2 is an important genetic modifier of ALS-FTD. We found that coexpression of intermediate polyglutamine repeats (30Q) of ATXN2 combined with C9orf72 depletion increases the aggregation of ATXN2 and neuronal toxicity. These results were confirmed in zebrafish embryos where partial C9orf72 knockdown along with intermediate (but not normal) repeat expansions in ATXN2 causes locomotion deficits and abnormal axonal projections from spinal motor neurons. These results demonstrate that C9orf72 plays an important role in the autophagy pathway while genetically interacting with another major genetic risk factor, ATXN2, to contribute to ALS-FTD pathogenesis.

  11. Community perceptions of repeat HIV-testing: experiences of the ANRS 12249 Treatment as Prevention trial in rural South Africa.

    Science.gov (United States)

    Orne-Gliemann, Joanna; Zuma, Thembelihle; Chikovore, Jeremiah; Gillespie, Natasha; Grant, Merridy; Iwuji, Collins; Larmarange, Joseph; McGrath, Nuala; Lert, France; Imrie, John

    2016-01-01

    In the context of the ANRS 12249 Treatment as Prevention (TasP) trial, we investigated perceptions of regular and repeat HIV-testing in rural KwaZulu-Natal (South Africa), an area of very high HIV prevalence and incidence. We conducted two qualitative studies, before (2010) and during the early implementation stages of the trial (2013-2014), to appreciate the evolution in community perceptions of repeat HIV-testing over this period of rapid changes in HIV-testing and treatment approaches. Repeated focus group discussions were organized with young adults, older adults and mixed groups. Repeat and regular HIV-testing was overall well perceived before, and well received during, trial implementation. Yet community members were not able to articulate reasons why people might want to test regularly or repeatedly, apart from individual sexual risk-taking. Repeat home-based HIV-testing was considered as feasible and convenient, and described as more acceptable than clinic-based HIV-testing, mostly because of privacy and confidentiality. However, socially regulated discourses around appropriate sexual behaviour and perceptions of stigma and prejudice regarding HIV and sexual risk-taking were consistently reported. This study suggests several avenues to improve HIV-testing acceptability, including implementing diverse and personalised approaches to HIV-testing and care, and providing opportunities for antiretroviral therapy initiation and care at home.

  12. Repeat testing of low-level HIV-1 RNA: assay performance and implementation in clinical trials.

    Science.gov (United States)

    White, Kirsten; Garner, Will; Wei, Lilian; Eron, Joseph J; Zhong, Lijie; Miller, Michael D; Martin, Hal; Plummer, Andrew; Tran-Muchowski, Cecilia; Lindstrom, Kim; Porter, James; Piontkowsky, David; Light, Angela; Reiske, Heinz; Quirk, Erin

    2018-05-15

    Assess the performance of HIV-1 RNA repeat testing of stored samples in cases of low-level viremia during clinical trials. Prospective and retrospective analysis of randomized clinical trial samples and reference standards. To evaluate assay variability of the Cobas AmpliPrep/Cobas TaqMan HIV-1 Test, v2.0, three separate sources of samples were utilized: the World Health Organization (WHO) HIV reference standard (assayed using 50 independent measurements at six viral loads <200 copies/ml), retrospective analysis of four to six aliquots of plasma samples from four clinical trial participants, and prospective repeat testing of 120 samples from participants in randomized trials with low-level viremia. The TaqMan assay on the WHO HIV-1 RNA standards at viral loads <200 copies/ml performed within the expected variability according to assay specifications. However, standards with low viral loads of 36 and 18 copies/ml reported values of ≥ 50 copies/ml in 66 and 18% of tests, respectively. In participants treated with antiretrovirals who had unexpected viremia of 50-200 copies/ml after achieving <50 copies/ml, retesting of multiple aliquots of stored plasma found <50 copies/ml in nearly all cases upon retesting (14/15; 93%). Repeat testing was prospectively implemented in four clinical trials for all samples with virologic rebound of 50-200 copies/ml (n = 120 samples from 92 participants) from which 42% (50/120) had a retest result of less than 50 copies/ml and 58% (70/120) retested ≥ 50 copies/ml. The TaqMan HIV-1 RNA assay shows variability around 50 copies/ml that affects clinical trial results and may impact clinical practice. In participants with a history of viral load suppression, unexpected low-level viremia may be because of assay variability rather than low drug adherence or true virologic failure. Retesting a stored aliquot of the same sample may differentiate between assay variability and virologic failure as the source of viremia

  13. Pyrrolizidine Alkaloids: Testing for Toxic Constituents of Comfrey.

    Science.gov (United States)

    Vollmer, John J.; And Others

    1987-01-01

    Discusses the possibilities of toxins present in medicinal herbs. Describes an experiment in which toxic constituents can be selectively detected by thin-layer chromatography and NMR spectroscopy. (TW)

  14. OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

    Science.gov (United States)

    Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

    2014-08-01

    The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Masonry fireplace emissions test method: Repeatability and sensitivity to fueling protocol.

    Science.gov (United States)

    Stern, C H; Jaasma, D R; Champion, M R

    1993-03-01

    A test method for masonry fireplaces has been evaluated during testing on six masonry fireplace configurations. The method determines carbon monoxide and particulate matter emission rates (g/h) and factors (g/kg) and does not require weighing of the appliance to determine the timing of fuel loading.The intralaboratory repeatability of the test method has been determined from multiple tests on the six fireplaces. For the tested fireplaces, the ratio of the highest to lowest measured PM rate averaged 1.17 and in no case was greater than 1.32. The data suggest that some of the variation is due to differences in fuel properties.The influence of fueling protocol on emissions has also been studied. A modified fueling protocol, tested in large and small fireplaces, reduced CO and PM emission factors by roughly 40% and reduced CO and PM rates from 0 to 30%. For both of these fireplaces, emission rates were less sensitive to fueling protocol than emission factors.

  16. Application of toxicity testing in the evaluation of reclamation options for oil sands fine tails

    International Nuclear Information System (INIS)

    Nelson, L.R.; MacKinnon, M.; Gulley, J.R.

    1993-01-01

    The hot water process for the extraction of bitumen from oil sands leads to the production of large volumes of wastewater and the formation of a large inventory of fine clay tailings. This fine tailings material and its associated water are acutely toxic to various aquatic test organisms during bioassays. An overview is presented of toxicity testing at Syncrude and Suncor, the application of toxicity testing to fine tailings management, and the role in reclamation planning. The main acutely toxic component of the tailings is the polar organic acid fraction, specifically naphthanates. These naphthanates are readily degraded biologically by indigenous microbial populations. Toxicity testing is aimed at assessing the degree of both acute and chronic toxicity and the long term potential for the input of toxins into the environment from various proposed reclamation measures. 28 refs., 6 figs., 2 tabs

  17. Dredged Material Evaluations: Review of Zooplankton Toxicity Test Methods for Marine Water Quality Evaluations

    Science.gov (United States)

    2016-09-01

    term impacts of the DM while settling through the water column (elutriate toxicity tests), and long-term toxicity (whole sediment toxicity tests) and...elutriates are prepared according to guidance (USEPA/USACE 1991; 1998) by mixing sediment and site water and allowing settling for prescribed periods...of water and waste water . 17th ed. Washington, DC: APHA. Arnold, W. R., R. L. Diamond, and D. S. Smith. 2010a. The effects of salinity, pH, and

  18. The human repeated insult patch test in the 21st century: a commentary.

    Science.gov (United States)

    Basketter, David A

    2009-01-01

    The human repeated insult patch test (HRIPT) is over half a century old, but is still used in several countries as a confirmatory test in the safety evaluation of skin sensitizers. This is despite the criticism it receives from an ethical perspective and regarding the scientific validity of such testing. In this commentary, the HRIPT is reviewed, with emphasis on ethical aspects and where the test can, and cannot, contribute in a scientifically meaningful manner to safety evaluation. It is concluded that where there is a specific rationale for testing, for example, to substantiate a no-effect level for a sensitizing chemical or to ensure that matrix effects are not making an unexpected contribution to sensitizing potency, then rigorous independent review may confirm that an HRIPT is ethical and scientifically justifiable. The possibility that sensitization may be induced in volunteers dictates that HRIPTs should be conducted rarely and in cases where the benefits overwhelmingly outweigh the risk. However, for the very large majority of HRIPTs conducted concerning the risk of skin sensitization, there is neither scientific justification nor any other merit.

  19. Improving toxicity assessment of pesticide mixtures: the use of polar passive sampling devices extracts in microalgae toxicity tests

    Directory of Open Access Journals (Sweden)

    Sandra KIM TIAM

    2016-09-01

    Full Text Available Complexity of contaminants exposure needs to be taking in account for an appropriate evaluation of risks related to mixtures of pesticides released in the ecosystems. Toxicity assessment of such mixtures can be made through a variety of toxicity tests reflecting different level of biological complexity. This paper reviews the recent developments of passive sampling techniques for polar compounds, especially Polar Organic Chemical Integrative Samplers (POCIS and Chemcatcher® and the principal assessment techniques using microalgae in laboratory experiments. The progresses permitted by the coupled use of such passive samplers and ecotoxicology testing as well as their limitations are presented. Case studies combining passive sampling devices (PSD extracts and toxicity assessment toward microorganisms at different biological scales from single organisms to communities level are presented. These case studies, respectively aimed i at characterizing the toxic potential of waters using dose-response curves, and ii at performing microcosm experiments with increased environmental realism in the toxicant exposure in term of cocktail composition and concentration. Finally perspectives and limitations of such approaches for future applications in the area of environmental risk assessment are discussed.

  20. Standardized toxicity testing may underestimate ecotoxicity: Environmentally relevant food rations increase the toxicity of silver nanoparticles to Daphnia.

    Science.gov (United States)

    Stevenson, Louise M; Krattenmaker, Katherine E; Johnson, Erica; Bowers, Alexandra J; Adeleye, Adeyemi S; McCauley, Edward; Nisbet, Roger M

    2017-11-01

    Daphnia in the natural environment experience fluctuations in algal food supply, with periods when algal populations bloom and seasons when Daphnia have very little algal food. Standardized chronic toxicity tests, used for ecological risk assessment, dictate that Daphnia must be fed up to 400 times more food than they would experience in the natural environment (outside of algal blooms) for a toxicity test to be valid. This disconnect can lead to underestimating the toxicity of a contaminant. We followed the growth, reproduction, and survival of Daphnia exposed to 75 and 200 µg/L silver nanoparticles (AgNPs) at 4 food rations for up to 99 d and found that AgNP exposure at low, environmentally relevant food rations increased the toxicity of AgNPs. Exposure to AgNP at low food rations decreased the survival and/or reproduction of individuals, with potential consequences for Daphnia populations (based on calculated specific population growth rates). We also found tentative evidence that a sublethal concentration of AgNPs (75 µg/L) caused Daphnia to alter energy allocation away from reproduction and toward survival and growth. The present findings emphasize the need to consider resource availability, and not just exposure, in the environment when estimating the effect of a toxicant. Environ Toxicol Chem 2017;36:3008-3018. © 2017 SETAC. © 2017 SETAC.

  1. Antidepressant-like effect of oleanolic acid in mice exposed to the repeated forced swimming test.

    Science.gov (United States)

    Yi, Li-Tao; Li, Jing; Liu, Qing; Geng, Di; Zhou, Ya-Fei; Ke, Xiao-Qing; Chen, Huan; Weng, Lian-Jin

    2013-05-01

    The study aimed to explore the antidepressant-like effect of oleanolic acid and its possible mechanism related to the monoaminergic system and neurotrophin in mice exposed to the repeated forced swimming test (FST). Both the duration and the latency of immobility affected by oleanolic acid (10, 20 and 40 mg/kg) were evaluated in the FST repeated at intervals on days 1, 7 and 14, followed by neurochemical and brain-derived neurotrophic factor (BDNF) analyses in the mouse brain regions of frontal cortex and whole hippocampus. A repeated analysis of variance (ANOVA) indicated that over retesting the immobility time increased, whereas latency to immobility tended to decrease. Minute-by-minute analysis showed that immobility time also increased during the 4-min course of the test. In addition, post-hoc Dunnett's test demonstrated that sub-chronic and chronic, but not acute, oleanolic acid treatment reduced the immobility time (sub-chronic: 20 mg/kg, 43.5%; chronic: 10 mg/kg, 19.3%; 20 mg/kg, 31.8%) and increased the latency to immobility (sub-chronic: 10 mg/kg, 60.6%; 20 mg/kg, 80.1%; chronic: 10 mg/kg, 121.8%; 20 mg/kg, 140.8%; 40 mg/kg, 80.0%). Furthermore, chronic administration of oleanolic acid significantly increased serotonin (5-HT) levels (frontal cortex: 44.5%, 41.9%, 27.5% for 10, 20, 40 mg/kg; hippocampus: 57.2%, 80.9% for 10, 20 mg/kg), decreased 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio (frontal cortex: 31.6%, 30.1%, 23.5%; hippocampus: 40.6%, 47.7%, 29.2% for 10, 20, 40 mg/kg) and elevated norepinephrine (NE) levels (hippocampus: 20 mg/kg, 45.4%) but did not alter dopamine (DA) levels. Moreover, BDNF levels in the two brain regions were also elevated by chronic oleanolic acid treatment (frontal cortex: 20 mg/kg, 67.2%; hippocampus: 10 mg/kg, 36.4%; 20 mg/kg, 55.1%). Taken together, these findings imply that functions of 5-HT, NE and BDNF may be involved in the antidepressant-like effect of oleanolic acid.

  2. Establishing the Test-Retest Reliability & Concurrent Validity for the Repeat Ice Skating Test (RIST) in Adolescent Male Ice Hockey Players

    Science.gov (United States)

    Power, Allan; Faught, Brent E.; Przysucha, Eryk; McPherson, Moira; Montelpare, William

    2012-01-01

    In this study the authors examine the test-retest reliability and concurrent validity of the Repeat Ice Skating Test (RIST). This was an on-ice field anaerobic test that measured average peak power and was validated with 3 anaerobic lab tests: (a) vertical jump, (b) the Margaria-Kalamen stair test, and (c) the Wingate Anaerobic Test. The…

  3. The Adverse Outcome Pathway: A conceptual framework to support toxicity testing in the 21st century

    Science.gov (United States)

    The field of regulatory toxicity testing is at a turning point. The U.S. National Research Council (NRC) envisioned a shift away from traditional toxicity testing and towards a focused effort to explore and understand pathways perturbed by biologically active substances or their ...

  4. Significance of Intratracheal Instillation Tests for the Screening of Pulmonary Toxicity of Nanomaterials.

    Science.gov (United States)

    Morimoto, Yasuo; Izumi, Hiroto; Yoshiura, Yukiko; Fujisawa, Yuri; Fujita, Katsuhide

    Inhalation tests are the gold standard test for the estimation of the pulmonary toxicity of respirable materials. Intratracheal instillation tests have been used widely, but they yield limited evidence of the harmful effects of respirable materials. We reviewed the effectiveness of intratracheal instillation tests for estimating the hazards of nanomaterials, mainly using research papers featuring intratracheal instillation and inhalation tests centered on a Japanese national project. Compared to inhalation tests, intratracheal instillation tests induced more acute inflammatory responses in the animal lung due to a bolus effect regardless of the toxicity of the nanomaterials. However, nanomaterials with high toxicity induced persistent inflammation in the chronic phase, and nanomaterials with low toxicity induced only transient inflammation. Therefore, in order to estimate the harmful effects of a nanomaterial, an observation period of 3 months or 6 months following intratracheal instillation is necessary. Among the endpoints of pulmonary toxicity, cell count and percentage of neutrophil, chemokines for neutrophils and macrophages, and oxidative stress markers are considered most important. These markers show persistent and transient responses in the lung from nanomaterials with high and low toxicity, respectively. If the evaluation of the pulmonary toxicity of nanomaterials is performed in not only the acute but also the chronic phase in order to avoid the bolus effect of intratracheal instillation and inflammatory-related factors that are used as endpoints of pulmonary toxicity, we speculate that intratracheal instillation tests can be useful for screening for the identification of the hazard of nanomaterials through pulmonary inflammation.

  5. Enhancing the applicability and predictability of the embryonic stem cell test for developmental toxicity

    NARCIS (Netherlands)

    de Jong, E.

    2012-01-01

    Within the full risk assessment of a chemical, developmental toxicity testing is one of the endpoints that require the highest percentage of experimental animals. With the high number of experimental animals, cost and time involved in in vivo developmental toxicity testing there is an urgent need

  6. Repeatability of quantitative sensory testing in healthy cats in a clinical setting with comparison to cats with osteoarthritis.

    Science.gov (United States)

    Addison, Elena S; Clements, Dylan N

    2017-12-01

    Objectives The aim of this study was to evaluate the repeatability of quantitative sensory tests (QSTs) in a group of healthy untrained cats (n = 14) and to compare the results with those from cats with osteoarthritis (n = 7). Methods Peak vertical force (PVF) and vertical impulse were measured on a pressure plate system. Thermal sensitivity was assessed using a temperature-controlled plate at 7°C and 40°C. Individual paw lifts and overall duration of paw lifts were counted and measured for each limb. Paw withdrawal thresholds were measured using manual and electronic von Frey monofilaments (MVF and EVF, respectively) applied to the metacarpal or metatarsal pads. All measurements were repeated twice to assess repeatability of the tests. Results In healthy cats all tests were moderately repeatable. When compared with cats with osteoarthritis the PVF was significantly higher in healthy hindlimbs in repeat 1 but not in repeat 2. Cats with osteoarthritis of the forelimbs showed a decrease in the frequency of paw lifts on the 7°C plate compared with cats with healthy forelimbs, and the duration of paw lifts was significantly less than healthy forelimbs in the first repeat but not in the second repeat. Osteoarthritic limbs had significantly lower paw withdrawal thresholds with both MVF and EVF than healthy limbs. Conclusions and relevance QSTs are moderately repeatable in untrained cats. Kinetic gait analysis did not permit differentiation between healthy limbs and those with osteoarthritis, but thermal sensitivity testing (cold) does. Sensory threshold testing can differentiate osteoarthritic and healthy limbs, and may be useful in the diagnosis and monitoring of this condition in cats in the clinical setting.

  7. [Necessity of repeated roll test in horizontal semicircular canalithasis positioned diagnosis].

    Science.gov (United States)

    Lu, H H; Zhao, Y; Chen, T S; Xu, K X; Wang, W; Liu, Q; Wen, C; Li, S S; Li, X J; Han, X; Lin, P

    2016-04-07

    To investigate the influence of repeated roll test in horizontal semicircular canalithasis(HSC-Can) positioned diagnosis, so as to investigate the cecessity of repeated roll test. The patients with a chief complaint of positional vertigo accepted two consecutive cycles roll test, the evoked nystagmus characteristics of each cycle recorded by video-nystagmuograph(VNG), whose direction, intensity, time and other parameters characteristics were analyzed in 51 HSC-Can. Horizontal nystagmus in the same direction with turning were induced in HSC-Can roll test. In 51 HSC-Can, roll test cycle 1 and cycle 2 induced nystagmus same strength side in 26 cases(51.0%), of which 19 cases with stronger nystagmus intensity in cycle 2, another 7 cases were weaker; the opposite strength side of the two loops induced nystagmus, and cycle 1 evoked nystagmus intensity were weaker than cycle 2, based on cycle 2 results determined HSC-Can affected side in 25 cases (49.0%). Lesion and normal side in cycle 1 induced nystagmus duration (x±s, the same below) were (13.4±11.5)s and (14.1±9.9)s, respectively intensity (18.1±22.4)°/s and (13.0±12.0)°/s; as in cycle 2 induced nystagmus duration was (20.7±10.2)s and (18.0±12.0)s, strength respectively(40.4±28.0)°/s and (15.6 ±11.2)°/s. Cycle 2 ipsilateral rotor position evoked nystagmus showed longer duration and stronger intensity than cycle 1. Between two cycle induced ipsilateral nystagmus duration, intensity differences were statistically significant (t values were -4.233 and -5.154, P=0.000). 51 HSC-Can patients, 44 patients selected repositioning maneuver, after 1-2 times of maneuver, 41 cases (93.2%) showed complete resolution of symptoms, all cases's symptoms were improved; other 7 patients selected medication only. The proposed suspicious HSC-Can patients should receive at least two cycles roll test, and mainly in the second cycle could determine the location of the responsible semicircular canals.

  8. Reliability characteristics and applicability of a repeated sprint ability test in male young soccer players

    DEFF Research Database (Denmark)

    Castagna, Carlo; Francini, Lorenzo; Krustrup, Peter

    2018-01-01

    The aim of this study was to examine the usefulness and reliability characteristics of a repeated sprint ability test considering 5 line sprints of 30-m interspersed with 30-s of active recovery in non-elite outfield young male soccer players. Twenty-six (age 14.9±1.2 years, height 1.72±0.12 cm......, body mass 62.2±5.1 kg) players were tested 48 hours and 7 days apart for 5x30-m performance over 5 trials (T1-T5). Short- (T1-T2) and long-term reliability (T1-T3-T4-T5) were assessed with Intraclass Correlation Coefficient (ICC) and with typical error for measurement (TEM). Short- and long...... study revealed that the 5x30-m sprint test is a reliable field test in the short and long-term when the sum of sprint times and the best sprint performance are considered as outcome variables. Sprint performance decrements variables showed large variability across trials....

  9. [Subchronic toxicity testing of mold-ripened cheese].

    Science.gov (United States)

    Schoch, U; Lüthy, J; Schlatter, C

    1984-08-01

    The biological effects of known mycotoxins of Penicillium roqueforti or P. camemberti and other still unknown, but potentially toxic metabolites in mould ripened cheese (commercial samples of Blue- and Camembert cheese) were investigated. High amounts of mycelium (equivalents of 100 kg cheese/man and day) were fed to mice in a subchronic feeding trial. The following parameters were determined: development of body weight, organ weights, hematology, blood plasma enzymes. No signs of adverse effects produced by cheese mycotoxins could be detected after 28 days. No still unknown toxic metabolites could be demonstrated. From these results no health hazard from the consumption of mould ripened cheese, even in high amounts, appears to exist.

  10. Repeated use of computerized case simulations in a test format does not present a security risk.

    Science.gov (United States)

    Lynch, T G; Zadalis, R J; Schneider, P D

    1999-03-01

    Computer-based examination formats permit evaluation of patient care strategies in a realistic context. Because such examinations are complex and difficult to develop, the same case simulations must often be used on multiple occasions. To determine if repeated, serial administration of computerized case simulations influences performance, 8 simulations were administered over 2 consecutive years to 252 third-year medical students at the conclusion of 16 surgical clerkship rotations (8 per year). One-way analyses of variance were used to compare scores across rotations during the year and to compare scores between 2 consecutive academic years. Scheffe pairwise comparisons were used to identify trends within each academic year. The data demonstrate an increase in scores across rotations during the year. There is, however, no difference between scores in successive years. The data are consistent with an increase in knowledge during the course of the year, without evidence that test information transfer influences the performance of successive classes.

  11. Repeat confirmatory testing for persons with discordant whole blood and oral fluid rapid HIV test results: findings from post marketing surveillance.

    Science.gov (United States)

    Wesolowski, Laura G; Mackellar, Duncan A; Ethridge, Steven F; Zhu, Julia H; Owen, S Michele; Sullivan, Patrick S

    2008-02-06

    Reactive oral fluid and whole blood rapid HIV tests must be followed with a confirmatory test (Western blot (WB), immunofluorescent assay (IFA) or approved nucleic acid amplification test (NAAT)). When the confirmatory result is negative or indeterminate (i.e. discordant with rapid result), repeat confirmatory testing should be conducted using a follow-up specimen. Previous reports have not described whether repeat testing adequately resolves the HIV-infection status of persons with discordant results. Post-marketing surveillance was conducted in 368 testing sites affiliated with 14 state and 2 city health departments from August 11, 2004 to June 30, 2005 and one health department through December 31, 2005. For persons with discordant results, data were collected on demographics, risk behaviors, HIV test results and specimen types. Persons with repeat confirmatory results were classified as HIV-infected or uninfected. Regression models were created to assess risk factors for not having repeat testing. Of 167,371 rapid tests conducted, 2589 (1.6%) were reactive: of these, 2417 (93%) had positive WB/IFA, 172 (7%) had negative or indeterminate WB/IFA. Of 89/172 (52%) persons with a repeat confirmatory test: 17 (19%) were HIV-infected, including 3 with indeterminate WB and positive NAAT; 72 (81%) were uninfected, including 12 with repeat indeterminate WB. Factors associated with HIV-infection included having an initial indeterminate WB/IFA (vs. negative) (ptest [adjusted OR 2.6, 95% CI (1.3, 4.9)]. Though only half of persons with discordant results had repeat confirmatory testing, of those who did, nearly one in five were HIV-infected. These findings underscore the need for rapid HIV testing programs to increase repeat confirmatory testing for persons with discordant results. Because of the lower sensitivity of oral fluid WBs, confirmatory testing following a reactive rapid test should be conducted using serum or plasma, when possible.

  12. Allium -test as a tool for toxicity testing of environmental radioactive-chemical mixtures

    International Nuclear Information System (INIS)

    Oudalova, A A; Pyatkova, S V; Geras’kin, S A; Dikareva, N S

    2017-01-01

    Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium -test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium -test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds. (paper)

  13. Allium-test as a tool for toxicity testing of environmental radioactive-chemical mixtures

    Science.gov (United States)

    Oudalova, A. A.; Geras'kin, S. A.; Dikareva, N. S.; Pyatkova, S. V.

    2017-01-01

    Bioassay-based approaches have been propagated to assess toxicity of unknown mixtures of environmental contaminants, but it was rarely applied in cases of chemicals with radionuclides combinations. Two Allium-test studies were performed to assess environmental impact from potential sources of combined radioactive-chemical pollution. Study sites were located at nuclear waste storage facilities in European and in Far-Eastern parts of Russia. As environmental media under impact, waters from monitor wells and nearby water bodies were tested. Concentrations of some chemicals and radionuclides in the samples collected enhanced the permitted limits. Cytogenetic and cytotoxic effects were used as biological endpoints, namely, frequency and spectrum of chromosome aberrations and mitotic abnormalities in anatelophase cells as well as mitotic activity in Allium root tips. Sample points were revealed where waters have an enhanced mutagenic potential. The findings obtained could be used to optimize monitoring system and advance decision making on management and rehabilitation of industrial sites. The Allium-test could be recommended and applied as an effective tool for toxicity testing in case of combined contamination of environmental compartments with radionuclides and chemical compounds.

  14. 78 FR 69414 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2013-11-19

    ...; Acute emulsion polymerization in Inhalation Toxicity in paper, textile, fiber, and Rats; Bacterial.../ Reproduction Development Toxicity. Note: CAS No. = Chemical Abstracts Service Registry Number. Authority: 15 U...

  15. Repeated subcutaneous administrations of krokodil causes skin necrosis and internal organs toxicity in Wistar rats: putative human implications.

    Science.gov (United States)

    Alves, Emanuele Amorim; Brandão, Pedro; Neves, João Filipe; Cravo, Sara Manuela; Soares, José Xavier; Grund, Jean-Paul C; Duarte, José Alberto; Afonso, Carlos M M; Pereira Netto, Annibal Duarte; Carvalho, Félix; Dinis-Oliveira, Ricardo Jorge

    2017-05-01

    "Krokodil" is the street name for an impure homemade drug mixture used as a cheap substitute for heroin, containing desomorphine as the main opioid. Abscesses, gangrene, thrombophlebitis, limb ulceration and amputations, jaw osteonecrosis, skin discoloration, ulcers, skin infections, and bleeding are some of the typical reported signs in humans. This study aimed to understand the toxicity of krokodil using Wistar male rats as experimental model. Animals were divided into seven groups and exposed subcutaneously to NaCl 0.9% (control), krokodil mixture free of psychotropic substances (blank krokodil), pharmaceutical grade desomorphine 1 mg/kg, and four different concentrations of krokodil (containing 0.125, 0.25, 0.5, and 1 mg/kg of desomorphine) synthesized accordingly to a "domestic" protocol followed by people who inject krokodil (PWIK). Daily injections for five consecutive days were performed, and animals were sacrificed 24 hr after the last administration. Biochemical and histological analysis were carried out. It was shown that the continuous use of krokodil may cause injury at the injection area, with formation of necrotic zones. The biochemical results evidenced alterations on cardiac and renal biomarkers of toxicity, namely, creatine kinase, creatine kinase-MB, and uric acid. Significant alteration in levels of reduced and oxidized glutathione on kidney and heart suggested that oxidative stress may be involved in krokodil-mediated toxicity. Cardiac congestion was the most relevant finding of continuous krokodil administration. These findings contribute notably to comprehension of the local and systemic toxicological impact of this complex drug mixture on major organs and will hopefully be useful for the development of appropriate treatment strategies towards the human toxicological effects of krokodil. Copyright © 2017 John Wiley & Sons, Ltd.

  16. The utility of repeat enzyme immunoassay testing for the diagnosis of Clostridium difficile infection: A systematic review of the literature

    Directory of Open Access Journals (Sweden)

    P S Garimella

    2012-01-01

    Full Text Available Over the last 20 years, the prevalence of healthcare-associated Clostridium difficile (C. diff disease has increased. While multiple tests are available for the diagnosis of C. diff infection, enzyme immunoassay (EIA testing for toxin is the most used. Repeat EIA testing, although of limited utility, is common in medical practice. To assess the utility of repeat EIA testing to diagnose C. diff infections. Systematic literature review. Eligible studies performed >1 EIA test for C. diff toxin and were published in English. Electronic searches of MEDLINE and EMBASE were performed and bibliographies of review articles and conference abstracts were hand searched. Of 805 citations identified, 32 were reviewed in detail and nine were included in the final review. All studies except one were retrospective chart reviews. Seven studies had data on number of participants (32,526, and the overall reporting of test setting and patient characteristics was poor. The prevalence of C. diff infection ranged from 9.1% to 18.5%. The yield of the first EIA test ranged from 8.4% to 16.6%, dropping to 1.5-4.7% with a second test. The utility of repeat testing was evident in outbreak settings, where the yield of repeat testing was 5%. Repeat C. diff testing for hospitalized patients has low clinical utility and may be considered in outbreak settings or when the pre-test probability of disease is high. Future studies should aim to identify patients with a likelihood of disease and determine the utility of repeat testing compared with empiric treatment.

  17. Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 22). Effects of 2- and 4-week administration of theobromine on the testis.

    Science.gov (United States)

    Funabashi, H; Fujioka, M; Kohchi, M; Tateishi, Y; Matsuoka, N

    2000-10-01

    The effects of theobromine, a xanthine derivative, on the testis were compared between rats dosed for 2 and 4 weeks to determine whether a 2-week dosing period is long enough to detect toxicity. Theobromine was administered orally to male Sprague-Dawley rats at dose levels of 250 and 500 mg/kg for 2 weeks starting at the age of 6 or 8 weeks, and for 4 weeks from the age of 6 weeks. Histopathological examination of reproductive organs revealed toxic findings in the testis at 500 mg/kg after 2 weeks of dosing at both ages, and at 250 and 500 mg/kg after 4 weeks of dosing. The primary findings were degeneration/necrosis and desquamation of spermatids and spermatocytes, vacuolization of seminiferous tubules, and multinucleated giant cell formation. These findings were present mainly in stages I-VI and XII-XIV. From these results, it is concluded that the toxic effects of theobromine on the testis can be detected by repeated dosing for 2 weeks as well as for 4 weeks.

  18. Testing of toxicity based methods to develop site specific clean up objectives - phase 1: Toxicity protocol screening and applicability

    International Nuclear Information System (INIS)

    Hamilton, H.; Kerr, D.; Thorne, W.; Taylor, B.; Zadnik, M.; Goudey, S.; Birkholz, D.

    1994-03-01

    A study was conducted to develop a cost-effective and practical protocol for using bio-assay based toxicity assessment methods for remediation of decommissioned oil and gas production, and processing facilities. The objective was to generate site-specific remediation criteria for contaminated sites. Most companies have used the chemical-specific approach which, however, did not meet the ultimate land use goal of agricultural production. The toxicity assessment method described in this study dealt with potential impairment to agricultural crop production and natural ecosystems. Human health concerns were not specifically addressed. It was suggested that chemical-specific methods should be used when human health concerns exist. . Results showed that toxicity tests will more directly identify ecological stress caused by site contamination than chemical-specific remediation criteria, which can be unnecessarily protective. 11 refs., 7 tabs., 6 figs

  19. ExpoCast: Exposure Science for Prioritization and Toxicity Testing

    Science.gov (United States)

    The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize l...

  20. Comparison of Weibull and Probit Analysis in Toxicity Testing of ...

    African Journals Online (AJOL)

    HP

    Keywords: Hunteria umbellata, Weibull model, Acute toxicity, Median lethal dose (LD50). Received: 7 November ... (PBPK) models [14,15], and (v) biologically-. Based Models: Moolgavkar-Venzon-Kundson. (MVK) model [16] and Ellwein and Cohen model [17]. ... Nigeria, Ibadan, where a sample with number. FHI107618 ...

  1. THE ROLE OF IONORGANIC ION IMBALANCE IN AQUATIC TOXICITY TESTING

    Science.gov (United States)

    This paper assessess the issue of ion imbalance, provides summary of applicable data, presents several successful technical tools to address toxicity resulting from salinity and ion imbalances, and discusses regulatory/compliance options to manage discharges with salinity/ion imb...

  2. Toxicity testing in the 21 century: defining new risk assessment approaches based on perturbation of intracellular toxicity pathways.

    Directory of Open Access Journals (Sweden)

    Sudin Bhattacharya

    Full Text Available The approaches to quantitatively assessing the health risks of chemical exposure have not changed appreciably in the past 50 to 80 years, the focus remaining on high-dose studies that measure adverse outcomes in homogeneous animal populations. This expensive, low-throughput approach relies on conservative extrapolations to relate animal studies to much lower-dose human exposures and is of questionable relevance to predicting risks to humans at their typical low exposures. It makes little use of a mechanistic understanding of the mode of action by which chemicals perturb biological processes in human cells and tissues. An alternative vision, proposed by the U.S. National Research Council (NRC report Toxicity Testing in the 21(st Century: A Vision and a Strategy, called for moving away from traditional high-dose animal studies to an approach based on perturbation of cellular responses using well-designed in vitro assays. Central to this vision are (a "toxicity pathways" (the innate cellular pathways that may be perturbed by chemicals and (b the determination of chemical concentration ranges where those perturbations are likely to be excessive, thereby leading to adverse health effects if present for a prolonged duration in an intact organism. In this paper we briefly review the original NRC report and responses to that report over the past 3 years, and discuss how the change in testing might be achieved in the U.S. and in the European Union (EU. EU initiatives in developing alternatives to animal testing of cosmetic ingredients have run very much in parallel with the NRC report. Moving from current practice to the NRC vision would require using prototype toxicity pathways to develop case studies showing the new vision in action. In this vein, we also discuss how the proposed strategy for toxicity testing might be applied to the toxicity pathways associated with DNA damage and repair.

  3. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

  4. Repeated Dose 28-Days Oral Toxicity Study of Carica papaya L. Leaf Extract in Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    Hussin Muhammad

    2012-04-01

    Full Text Available Carica papaya L. leaves have been used in ethnomedicine for the treatment of fevers and cancers. Despite its benefits, very few studies on their potential toxicity have been described. The aim of the present study was to characterize the chemical composition of the leaf extract from ‘Sekaki’ C. papaya cultivar by UPLC-TripleTOF-ESI-MS and to investigate the sub-acute oral toxicity in Sprague Dawley rats at doses of 0.01, 0.14 and 2 g/kg by examining the general behavior, clinical signs, hematological parameters, serum biochemistry and histopathology changes. A total of twelve compounds consisting of one piperidine alkaloid, two organic acids, six malic acid derivatives, and four flavonol glycosides were characterized or tentatively identified in the C. papaya leaf extract. In the sub-acute study, the C. papaya extract did not cause mortality nor were treatment-related changes in body weight, food intake, water level, and hematological parameters observed between treatment and control groups. Some biochemical parameters such as the total protein, HDL-cholesterol, AST, ALT and ALP were elevated in a non-dose dependent manner. Histopathological examination of all organs including liver did not reveal morphological alteration. Other parameters showed non-significant differences between treatment and control groups. The present results suggest that C. papaya leaf extract at a dose up to fourteen times the levels employed in practical use in traditional medicine in Malaysia could be considered safe as a medicinal agent.

  5. Implementation of repeat HIV testing during pregnancy in southwestern Kenya: progress and missed opportunities.

    Science.gov (United States)

    Rogers, Anna J; Akama, Eliud; Weke, Elly; Blackburn, Justin; Owino, George; Bukusi, Elizabeth A; Oyaro, Patrick; Kwena, Zachary A; Cohen, Craig R; Turan, Janet M

    2017-12-01

    Repeat HIV testing during the late antenatal period is crucial to identify and initiate treatment for pregnant women with incident HIV infection to prevent perinatal HIV transmission and keep mothers alive. In 2012, the Kenya Ministry of Health adopted international guidelines suggesting that pregnant women be offered retesting three months after an initial negative HIV test. Our objectives were to determine the current rate of antenatal repeat HIV testing; identify successes, missed opportunities and factors associated with retesting; and estimate the incidence of HIV during pregnancy. Retrospective analysis of longitudinal data was conducted for a cohort of 2145 women attending antenatal care clinic at a large district hospital in southwestern Kenya. Data were abstracted from registers for all women who attended the clinic from the years 2011 to 2014. Although 90.2% of women first came to clinic prior to their third trimester and 27.5% had at least four clinic visits, 58.0% of all women went to delivery without a retest. Missed opportunities for retesting included not returning to clinic at all, not returning when eligible, or late gestational age (>28 weeks) at first clinic visit making them ineligible for retesting (accounting for 14.2%, 26.8% and 9.6% of all clinic attendees respectively); and failure to be retested even when eligible at one or more visits (accounting for 73.2% of eligible returnees). Being unmarried and aged 20 or younger was associated with an increase in mean gestational age of first visit by 2.52 weeks (95% CI: 1.56, 3.48) and a 2.59 increased odds (95% CI: 1.90, 3.54) of failing to return to clinic, compared to those who were married and over 20 years of age. On retest, two women tested HIV positive, suggesting an incidence rate of 4.4 per 100 person-years. After adjusting for potential confounders, only later year of last menstrual period (2013 vs. 2012 and 2011) was associated with retesting. Adoption of retesting guidelines in 2012

  6. A comparison of sediment toxicity test methods at three Great Lake Areas of Concern

    Science.gov (United States)

    Burton, G. Allen; Ingersoll, Christopher G.; Burnett, LouAnn C.; Henry, Mary; Hinman, Mark L.; Klaine, Stephen J.; Landrum, Peter F.; Ross, Phillipe; Tuchman, Marc

    1996-01-01

    The significance of sediment contamination is often evaluated using sediment toxicity (bioassay) testing. There are relatively few “standardized” test methods for evaluating sediments. Popular sediment toxicity methods examine the extractable water (elutriate), interstitial water, or whole (bulk) sediment phases using test species spanning the aquatic food chain from bacteria to fish. The current study was designed to evaluate which toxicity tests were most useful in evaluations of sediment contamination at three Great Lake Areas of Concern. Responses of 24 different organisms including fish, mayflies, amphipods, midges, cladocerans, rotifers, macrophytes, algae, and bacteria were compared using whole sediment or elutriate toxicity assays. Sediments from several sites in the Buffalo River, Calumet River (Indiana Harbor), and Saginaw River were tested, as part of the U.S. Environmental Protection Agency's (USEPA) Assessment and Remediation of Contaminated Sediments (ARCS) Project. Results indicated several assays to be sensitive to sediment toxicity and able to discriminate between differing levels of toxicity. Many of the assay responses were significantly correlated to other toxicity responses and were similar based on factor analysis. For most applications, a test design consisting of two to three assays should adequately detect sediment toxicity, consisting of various groupings of the following species: Hyalella azteca, Ceriodaphnia dubia, Chironomus riparius, Chironomus tentans, Daphnia magna, Pimephales promelas, Hexagenia bilineata, Diporeia sp., Hydrilla verticillata, or Lemna minor.

  7. Repeatability indices for the Adams D-15 test for colour-normal and colour-defective adults.

    Science.gov (United States)

    Hovis, Jeffery K; Ramaswamy, Shankaran; Anderson, Matthew

    2004-07-01

    The Adams desaturated D-15 test was administered to individuals with normal colour vision or with congenital red-green colour vision defects to establish the repeatability of the test. One hundred subjects with normal colour vision and 64 subjects with defective colour vision participated in the study. Results were analysed from two different sessions to determine the repeatability of the test for different pass/fail criteria. The test was scored using both visual inspection of the score sheet and the modified Colour Difference Vector analysis (CDV) program. For both subject groups, the repeatability was lowest when a perfect arrangement was required for a pass and improved as more errors were allowed. The improvement in repeatability was greatest as the failure criterion changed from 'any mistake' to 'more than two crossings'. The kappa coefficient for the reliability of the defect classification was 0.38 for visual inspection and 0.59 for the CDV analysis. All the protans who failed the test at both sessions were classified correctly. Approximately 98 per cent of the colour-normals and 82 per cent of the colour-defectives would have the same pass/fail outcome on the Adams D-15 test conducted several days apart when the failure criterion was either one or more or two or more crossings. Individuals who make less than four crossings on the Adams D-15 should repeat the test to ensure confidence in the pass/fail result.

  8. Repeated change-of-direction test for collegiate male soccer players.

    Science.gov (United States)

    Mizuguchi, S; Gray, H; Calabrese, L S; Haff, G G; Sands, W A; Ramsey, M W; Cardinale, M; Stone, M H

    2014-08-01

    The aim of the study was to investigate the applicability of a repeated change-of-direction (RCoD) test for NCAA Division-I male soccer players. The RCoD test consisted of 5 diagonal direction changes per repetition with a soccer ball to be struck at the end. Each player performed 15 repetitions with approximately 10 seconds to jog back between repetitions. Data were collected in two sessions. In the first session, 13 players were examined for heart rate responses and blood lactate concentrations. In the second session, 22 players were examined for the test's ability to discriminate the primary from secondary players (78.0±16.1 and 10.4±13.3 minutes per match, respectively). Heart rate data were available only from 9 players due to artifacts. The peak heart rate (200.2±6.6 beats∙min-1: 99.9±3.0% maximum) and blood lactate concentration (14.8±2.4 mmol∙L-1 immediately after) resulted in approximately 3.5 and 6.4-fold increases from the resting values, respectively. These values appear comparable to those during intense periods of soccer matches. In addition, the average repetition time of the test was found to discriminate the primary (4.85±0.23 s) from the secondary players (5.10±0.24 s) (P=0.02). The RCoD test appears to induce physiological responses similar to intense periods of soccer matches with respect to heart rate and blood lactate concentration. Players with better average repetition times tend to be those who play major minutes.

  9. Aquatic toxicity testing for hazard identification of engineered nanoparticles

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard

    the traditionally applied, and determination of different exposure fractions such as the concentration of dissolved ions from ENPs and body burdens. Although these approaches are scientifically exploratory by nature, the aim is to generate data applicable for regulatory hazard identification of ENPs. The focus has......Within the last few decades, major advances in the field of nanotechnology have enabled production of engineered nanoparticles (ENPs) for various applications and consumer products already available on the market. ENPs may exhibit unique and novel properties compared to their bulk counterparts...... and the response axes. The actual exposure experienced by organisms may not be reflected by the ENPconcentration in medium, commonly applied as the exposure metric, and the responses of organisms may result from various toxic and non-toxic mechanisms occurring simultaneously. In this thesis, the challenges related...

  10. Guanicid and PHMG Toxicity Tests on Aquatic Organisms

    OpenAIRE

    Eva Poštulková; Radovan Kopp

    2016-01-01

    The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG). The aim of the study was to identify toxic effects of Guanicid and PHM...

  11. Sediment toxicity testing with the amphipod Ampelisca abdita in Calcasieu Estuary, Louisiana

    Science.gov (United States)

    Redmond, M.S.; Crocker, P.A.; McKenna, K.M.; Petrocelli, E.A.; Scott, K.J.; Demas, C.R.

    1996-01-01

    Discharges from chemical and petrochemical manufacturing facilities have contaminated portions of Louisiana's Calcasieu River estuary with a variety of organic and inorganic contaminants. As part of a special study, sediment toxicity testing was conducted to assess potential impact to the benthic community. Ten-day flow-through sediment toxicity tests with the amphipod Ampelisca abdita revealed significant toxicity at 68% (26 of 38) of the stations tested. A. abdita mortality was highest in the effluent-dominated bayous, which are tributaries to the Calcasieu River. Mortality was correlated with total heavy metal and total organic compound concentrations in the sediments. Ancillary experiments showed that sediment interstitial water salinity as low as 2.5 o/o-o did not significantly affect A. abdita's, response in the flow-through system; sediment storage for 7 weeks at 4??C did not significantly affect toxicity. Sediment toxicity to A. abdita was more prevalent than receiving water toxicity using three short-term chronic bioassays. Results suggest that toxicity testing using this amphipod is a valuable tool when assessing sediments containing complex contaminant mixtures and for assessing effects of pollutant loading over time. In conjunction with chemical analyses, the testing indicated that the effluent-dominated, brackish bayous (Bayou d'Inde and Bayou Verdine) were the portions of the estuary most impacted by toxicity.

  12. INDUSTRIAL ROBOT REPEATABILITY TESTING WITH HIGH SPEED CAMERA PHANTOM V2511

    Directory of Open Access Journals (Sweden)

    Jerzy Józwik

    2016-12-01

    Full Text Available Apart from accuracy, one of the parameters describing industrial robots is positioning accuracy. The parameter in question, which is the subject of this paper, is often the decisive factor determining whether to apply a given robot to perform certain tasks or not. Articulated robots are predominantly used in such processes as: spot weld-ing, transport of materials and other welding applications, where high positioning repeatability is required. It is therefore essential to recognise the parameter in question and to control it throughout the operation of the robot. This paper presents methodology for robot positioning accuracy measurements based on vision technique. The measurements were conducted with Phantom v2511 high-speed camera and TEMA Motion software, for motion analysis. The object of the measurements was a 6-axis Yaskawa Motoman HP20F industrial robot. The results of measurements obtained in tests provided data for the calculation of positioning accuracy of the robot, which was then juxtaposed against robot specifications. Also analysed was the impact of the direction of displacement on the value of attained pose errors. Test results are given in a graphic form.

  13. Attrition from Web-Based Cognitive Testing: A Repeated Measures Comparison of Gamification Techniques.

    Science.gov (United States)

    Lumsden, Jim; Skinner, Andy; Coyle, David; Lawrence, Natalia; Munafo, Marcus

    2017-11-22

    The prospect of assessing cognition longitudinally and remotely is attractive to researchers, health practitioners, and pharmaceutical companies alike. However, such repeated testing regimes place a considerable burden on participants, and with cognitive tasks typically being regarded as effortful and unengaging, these studies may experience high levels of participant attrition. One potential solution is to gamify these tasks to make them more engaging: increasing participant willingness to take part and reducing attrition. However, such an approach must balance task validity with the introduction of entertaining gamelike elements. This study aims to investigate the effects of gamelike features on participant attrition using a between-subjects, longitudinal Web-based testing study. We used three variants of a common cognitive task, the Stop Signal Task (SST), with a single gamelike feature in each: one variant where points were rewarded for performing optimally; another where the task was given a graphical theme; and a third variant, which was a standard SST and served as a control condition. Participants completed four compulsory test sessions over 4 consecutive days before entering a 6-day voluntary testing period where they faced a daily decision to either drop out or continue taking part. Participants were paid for each session they completed. A total of 482 participants signed up to take part in the study, with 265 completing the requisite four consecutive test sessions. No evidence of an effect of gamification on attrition was observed. A log-rank test showed no evidence of a difference in dropout rates between task variants (χ 2 2 =3.0, P=.22), and a one-way analysis of variance of the mean number of sessions completed per participant in each variant also showed no evidence of a difference (F 2,262 =1.534, P=.21, partial η 2 =0.012). Our findings raise doubts about the ability of gamification to reduce attrition from longitudinal cognitive testing studies

  14. Evaluation of Daphnia ambigua for Routine Aquatic Toxicity Testing at the Savannah River Site

    International Nuclear Information System (INIS)

    Specht, W.L.; Harmon, S.M.

    1997-09-01

    Short-term whole effluent toxicity testing, which is currently a requirement of the U.S. EPA's National Pollution Discharge Elimination System (NPDES), commonly uses the cladoceran species Ceriodaphnia dubia. Despite the advantages to using a common test species to model the toxic effects of effluents, it could be argued that toxicity test results would be more meaningful if a wider variety of test organisms were commonly used. One particular argument against C. dubia is that tests conducted with this species do not always reflect local, site-specific conditions. The careful selection and use of an indigenous test species would produce a more realistic model of local instream effects and would account for regional differences in water quality. Permitted effluent discharges from Savannah River Site (SRS), a government weapons facility operated by the U.S. Department of Energy, require toxicity testing with C. dubia. However, water quality in these receiving streams is markedly different (lower pH and hardness) from standard laboratory water used for the culturing and testing of C. dubia, and it has been shown that this receiving water presents varying degrees of toxicity to C. dubia. Based on these results, it is possible that toxic effects observed during an effluent study could be the result of test organism stress from the dilution water and not the effects of SRS effluents. Therefore, this study addressed the substitution of C. dubia with an indigenous cladoceran species, Daphnia ambigua for routine regulatory testing at SRS. Given the indigenous nature of this species, combined with the fact that it has been successfully cultured by other investigators, D. ambigua was ideal for consideration as a replacement for C. dubia, but further study of the overall success and sensitivity of laboratory-reared D. ambigua was required. This investigation determined that D. ambigua could be laboratory cultured with only minimal changes to established regulatory protocol and

  15. Evaluation of Pulmonary and Systemic Toxicity of Oil Dispersant (COREXIT EC9500A(®)) Following Acute Repeated Inhalation Exposure.

    Science.gov (United States)

    Roberts, Jenny R; Anderson, Stacey E; Kan, Hong; Krajnak, Kristine; Thompson, Janet A; Kenyon, Allison; Goldsmith, William T; McKinney, Walter; Frazer, David G; Jackson, Mark; Fedan, Jeffrey S

    2014-01-01

    Oil spill cleanup workers come into contact with numerous potentially hazardous chemicals derived from the oil spills, as well as chemicals applied for mitigation of the spill, including oil dispersants. In response to the Deepwater Horizon Macondo well oil spill in the Gulf of Mexico in 2010, a record volume of the oil dispersant, COREXIT EC9500A, was delivered via aerial applications, raising concern regarding potential health effects that may result from pulmonary exposure to the dispersant. The current study examined the effects on pulmonary functions, cardiovascular functions, and systemic immune responses in rats to acute repeated inhalation exposure of COREXIT EC9500A at 25 mg/m(3), five hours per day, over nine work days, or filtered air (control). At one and seven days following the last exposure, a battery of parameters was measured to evaluate lung function, injury, and inflammation; cardiovascular function; peripheral vascular responses; and systemic immune responses. No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following methacholine (MCh) inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM) to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP) responses to these agents; however, the baseline heart rate (HR) and HR responses to isoproterenol (ISO) were significantly elevated at one-day post exposure, with resolution by day 7. In summary, acute

  16. Evaluation of Pulmonary and Systemic Toxicity of Oil Dispersant (COREXIT EC9500A following Acute Repeated Inhalation Exposure

    Directory of Open Access Journals (Sweden)

    Jenny R. Roberts

    2014-01-01

    Full Text Available Introduction Oil spill cleanup workers come into contact with numerous potentially hazardous chemicals derived from the oil spills, as well as chemicals applied for mitigation of the spill, including oil dispersants. In response to the Deepwater Horizon Macondo well oil spill in the Gulf of Mexico in 2010, a record volume of the oil dispersant, COREXIT EC9500A, was delivered via aerial applications, raising concern regarding potential health effects that may result from pulmonary exposure to the dispersant. Methods The current study examined the effects on pulmonary functions, cardiovascular functions, and systemic immune responses in rats to acute repeated inhalation exposure of COREXIT EC9500A at 25 mg/m 3 , five hours per day, over nine work days, or filtered air (control. At one and seven days following the last exposure, a battery of parameters was measured to evaluate lung function, injury, and inflammation; cardiovascular function; peripheral vascular responses; and systemic immune responses. Results No significant alterations in airway reactivity were observed at one or seven days after exposure either in baseline values or following metha-choline (MCh inhalation challenge. Although there was a trend for an increase in lung neutrophils and phagocyte oxidant production at one-day post exposure, there were no significant differences in parameters of lung inflammation. In addition, increased blood monocytes and neutrophils, and decreased lymphocyte numbers at one-day post exposure also did not differ significantly from air controls, and no alterations in splenocyte populations, or serum or spleen immunoglobulin M (IgM to antigen were observed. There were no significant differences in peripheral vascular responsiveness to vasoconstrictor and vasodilator agonists or in blood pressure (BP responses to these agents; however, the baseline heart rate (HR and HR responses to isoproterenol (ISO were significantly elevated at one-day post exposure

  17. In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles.

    NARCIS (Netherlands)

    Park, M.V.; Annema, W.; Salvati, A.; Lesniak, A.; Elsaesser, A.; Barnes, C.; McKerr, G.; Howard, C.; Lynch, I.; Dawson, K.; Piersma, A.H.; de Jong, W.H.

    2009-01-01

    While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining

  18. Sensitivity of submersed freshwater macrophytes and endpoints in laboratory toxicity tests

    International Nuclear Information System (INIS)

    Arts, Gertie H.P.; Belgers, J. Dick M.; Hoekzema, Conny H.; Thissen, Jac T.N.M.

    2008-01-01

    The toxicological sensitivity and variability of a range of macrophyte endpoints were statistically tested with data from chronic, non-axenic, macrophyte toxicity tests. Five submersed freshwater macrophytes, four pesticides/biocides and 13 endpoints were included in the statistical analyses. Root endpoints, reflecting root growth, were most sensitive in the toxicity tests, while endpoints relating to biomass, growth and shoot length were less sensitive. The endpoints with the lowest coefficients of variation were not necessarily the endpoints, which were toxicologically most sensitive. Differences in sensitivity were in the range of 10-1000 for different macrophyte-specific endpoints. No macrophyte species was consistently the most sensitive. Criteria to select endpoints in macrophyte toxicity tests should include toxicological sensitivity, variance and ecological relevance. Hence, macrophyte toxicity tests should comprise an array of endpoints, including very sensitive endpoints like those relating to root growth. - A range of endpoints is more representative of macrophyte fitness than biomass and growth only

  19. The extended statistical analysis of toxicity tests using standardised effect sizes (SESs): a comparison of nine published papers.

    Science.gov (United States)

    Festing, Michael F W

    2014-01-01

    The safety of chemicals, drugs, novel foods and genetically modified crops is often tested using repeat-dose sub-acute toxicity tests in rats or mice. It is important to avoid misinterpretations of the results as these tests are used to help determine safe exposure levels in humans. Treated and control groups are compared for a range of haematological, biochemical and other biomarkers which may indicate tissue damage or other adverse effects. However, the statistical analysis and presentation of such data poses problems due to the large number of statistical tests which are involved. Often, it is not clear whether a "statistically significant" effect is real or a false positive (type I error) due to sampling variation. The author's conclusions appear to be reached somewhat subjectively by the pattern of statistical significances, discounting those which they judge to be type I errors and ignoring any biomarker where the p-value is greater than p = 0.05. However, by using standardised effect sizes (SESs) a range of graphical methods and an over-all assessment of the mean absolute response can be made. The approach is an extension, not a replacement of existing methods. It is intended to assist toxicologists and regulators in the interpretation of the results. Here, the SES analysis has been applied to data from nine published sub-acute toxicity tests in order to compare the findings with those of the author's. Line plots, box plots and bar plots show the pattern of response. Dose-response relationships are easily seen. A "bootstrap" test compares the mean absolute differences across dose groups. In four out of seven papers where the no observed adverse effect level (NOAEL) was estimated by the authors, it was set too high according to the bootstrap test, suggesting that possible toxicity is under-estimated.

  20. The extended statistical analysis of toxicity tests using standardised effect sizes (SESs: a comparison of nine published papers.

    Directory of Open Access Journals (Sweden)

    Michael F W Festing

    Full Text Available The safety of chemicals, drugs, novel foods and genetically modified crops is often tested using repeat-dose sub-acute toxicity tests in rats or mice. It is important to avoid misinterpretations of the results as these tests are used to help determine safe exposure levels in humans. Treated and control groups are compared for a range of haematological, biochemical and other biomarkers which may indicate tissue damage or other adverse effects. However, the statistical analysis and presentation of such data poses problems due to the large number of statistical tests which are involved. Often, it is not clear whether a "statistically significant" effect is real or a false positive (type I error due to sampling variation. The author's conclusions appear to be reached somewhat subjectively by the pattern of statistical significances, discounting those which they judge to be type I errors and ignoring any biomarker where the p-value is greater than p = 0.05. However, by using standardised effect sizes (SESs a range of graphical methods and an over-all assessment of the mean absolute response can be made. The approach is an extension, not a replacement of existing methods. It is intended to assist toxicologists and regulators in the interpretation of the results. Here, the SES analysis has been applied to data from nine published sub-acute toxicity tests in order to compare the findings with those of the author's. Line plots, box plots and bar plots show the pattern of response. Dose-response relationships are easily seen. A "bootstrap" test compares the mean absolute differences across dose groups. In four out of seven papers where the no observed adverse effect level (NOAEL was estimated by the authors, it was set too high according to the bootstrap test, suggesting that possible toxicity is under-estimated.

  1. Clinical Utilization of Repeated Open Application Test Among American Contact Dermatitis Society Members.

    Science.gov (United States)

    Brown, Gabrielle E; Botto, Nina; Butler, Daniel C; Murase, Jenny E

    2015-01-01

    The repeated open application test (ROAT) provides useful information regarding allergens in suspected cases of allergic contact dermatitis; however, standardized methodology has not been established. The aim of this study was to assess how ROAT is used in clinical and research settings. We distributed a survey regarding ROAT practice to the American Contact Dermatitis Society and conducted a literature review of ROAT utilization in research. A total of 67 American Contact Dermatitis Society members participated in the survey. Respondents most frequently recommend application of leave-on products twice daily (46.0%) and rinse-off products once daily (43.5%). The most commonly used anatomical sites include the forearm (38.7%) and antecubital fossa (32.3%). Most respondents continue ROAT for 1 (49.2%) or 2 weeks (31.7%). Literature review of 32 studies (26 leave-on, 6 rinse-off) revealed that application frequency is most common at twice daily for both leave-on (96.2%) and rinse-off (50.0%) products. The most common anatomical site is the forearm (62.5%), with an overall study duration of 3 to 4 weeks (65.6%). When comparing ROAT clinical and research practice, the majority trend was consistent for leave-on product application frequency and anatomical site, but not for rinse-off product application frequency, or overall duration. Further research is needed to determine best practice recommendations.

  2. A study on the evaluation of dynamic stress intensity factor in repeated impact bending test

    International Nuclear Information System (INIS)

    Sim, Jae Ki; Cho, Gyu Jae; Han, Gill Young

    1988-01-01

    The purpose of the present paper was to establish the evaluation of the dynamic stress intensity factor in repeated impact three point bending test. Contact force between the impact bar and the cracked beam (simple supported beam) was analyzed by the using Hertz's contact law. In order to clarify the validity of theoretical analysis, experiments of dynamic stress intensity factir k I (t) are made on the cracked beam. The results obtained from this study are as follow: 1. In case of impact force analysis the theoretical result was obtained by the use of the Hertz's contact law. It's result was agreemant with the experimental result. Particularly, it was good agreement in the low impact velocity range. 2. The time variation of the dynamic stress intensity was determined by using the simple formula developed in this pqper. And the validity of it's result can be confirmed by experiment. Particlarly, this theoretical analysis was a good agreement to actual phenomena on from 0.3 msec to 0.65 msec. (Author)

  3. TPK Sarimukti, Cipatat, West Bandung compost toxicity test using Allium test

    Energy Technology Data Exchange (ETDEWEB)

    Wardini, Trimurti Hesti; Notodarmojo, Peni Astrini [Biology Study Program, School of Life Science and Technology, Bandung Institute of Technology (Indonesia)

    2015-09-30

    TPK Sarimukti, Cipatat, West Bandung produced 2 kinds of compost from traditional market waste, liquid and solid compost. The aim of this research is to evaluate toxicity of compost produced in TPK Sarimukti using shallots (Allium cepa). Tests carried out by treated shallots with liquid compost (2,5%, 5%, 10% and 12,5% (w/v)) or solid compost (25%, 50%, 75% and 100% (w/v)) for 48 hours. Results showed reduced root growth rate and mitotic index (MI) in accordance with increased concentrations of compost. Sub lethal concentrations are liquid compost 5% and 10% and solid compost 75%. Lethal concentrations are liquid compost 12,5 % and solid compost 100%. Micronuclei (MN) increased with increase in liquid compost concentration. MN found at very high frequencies in highest solid compost concentration (100%), but very low at lower concentrations. Cells with binuclei and cell necrosis increased with increasing concentrations of given compost. Nuclear anomalies (NA) found in high frequency in 75% and 100% solid compost. Based on research, we can conclude that liquid compost is more toxic because it can reduce MI and root growth rate at lower concentrations than solid compost. Both types of compost have genotoxic properties because it can induce chromosome aberration (CA), MN, binuclei and NA formation.

  4. Integrating the fish embryo toxicity test as triad element for sediment toxicity assessment based on the water framework directive approach

    Energy Technology Data Exchange (ETDEWEB)

    Bartzke, Mariana [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Dept. Bioanalytical Ecotoxicology, Helmholtz Centre for Environmental Research, UFZ, Leipzig (Germany); Delov, Vera [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany); Gobio GmbH, Aarbergen/Kettenbach (Germany); Ecotoxicology, Fraunhofer Inst. for Molecular Biology and Applied Ecology IME, Aachen (Germany); Stahlschmidt-Allner, Petra; Allner, Bernhard [Gobio GmbH, Aarbergen/Kettenbach (Germany); Oehlmann, Joerg [Dept. Aquatic Ecotoxicology, Goethe Univ. Frankfurt am Main (Germany)

    2010-04-15

    Purpose: The objective of this study was to complement analyses according to the European Union Water Framework Directive (WFD) with a sediment toxicity analysis as part of an integrated river assessment. To this end, Hessian water courses were analyzed using the sediment quality triad concept according to Chapman with chemical analyses, in situ effect evaluations, and ecotoxicological assessments. For the ecotoxicological assessment (fish embryo toxicity test with Danio rerio), a new evaluation scheme was developed, the fish teratogenicity index (FTI), that allows for a classification of sediments into ecological quality classes compliant to the WFD. Materials and methods sediment and macrozoobenthos samples were taken from tributaries of the rivers Fulda and Lahn. Sediments were characterized regarding particle size, carbon, heavy metals, and polyaromatic hydrocarbon content. Macroinvertebrate samples were taken via multi-habitat sampling. The fish embryo toxicity test with D. rerio was conducted as a contact assay on the basis of DIN 38415-6. Results and discussion The integrated assessment indicated a significant influence of heavy metals and carbon content on macroinvertebrate communities. The bioaccessibility of sediment pollutants were clearly demonstrated by the FTI, which showed a wide range of adverse effects. A significant linear relationship between metals and the FTI was detected. However, there was no statistically significant evidence that macroinvertebrate communities were affected by the hydromorphological quality clements at the sampling sites. Conclusions The new scheme for the assessment of fish embryo toxicity test was successfully applied. The results suggest that sediment compounds impact macroinvertebrate communities and early development of fish. It demonstrates that the quality of sediments should be evaluated on a routine basis as part of an integrated river assessment. (orig.)

  5. Repeat confirmatory testing for persons with discordant whole blood and oral fluid rapid HIV test results: findings from post marketing surveillance.

    Directory of Open Access Journals (Sweden)

    Laura G Wesolowski

    Full Text Available BACKGROUND: Reactive oral fluid and whole blood rapid HIV tests must be followed with a confirmatory test (Western blot (WB, immunofluorescent assay (IFA or approved nucleic acid amplification test (NAAT. When the confirmatory result is negative or indeterminate (i.e. discordant with rapid result, repeat confirmatory testing should be conducted using a follow-up specimen. Previous reports have not described whether repeat testing adequately resolves the HIV-infection status of persons with discordant results. METHODOLOGY: Post-marketing surveillance was conducted in 368 testing sites affiliated with 14 state and 2 city health departments from August 11, 2004 to June 30, 2005 and one health department through December 31, 2005. For persons with discordant results, data were collected on demographics, risk behaviors, HIV test results and specimen types. Persons with repeat confirmatory results were classified as HIV-infected or uninfected. Regression models were created to assess risk factors for not having repeat testing. PRINCIPAL FINDINGS: Of 167,371 rapid tests conducted, 2589 (1.6% were reactive: of these, 2417 (93% had positive WB/IFA, 172 (7% had negative or indeterminate WB/IFA. Of 89/172 (52% persons with a repeat confirmatory test: 17 (19% were HIV-infected, including 3 with indeterminate WB and positive NAAT; 72 (81% were uninfected, including 12 with repeat indeterminate WB. Factors associated with HIV-infection included having an initial indeterminate WB/IFA (vs. negative (p<0.001 and having an initial oral fluid WB (vs. serum (p<0.001. Persons who had male-female sex (vs. male-male sex were at increased risk for not having a repeat test [adjusted OR 2.6, 95% CI (1.3, 4.9]. CONCLUSIONS: Though only half of persons with discordant results had repeat confirmatory testing, of those who did, nearly one in five were HIV-infected. These findings underscore the need for rapid HIV testing programs to increase repeat confirmatory testing for

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

    NARCIS (Netherlands)

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

    2003-01-01

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

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

    NARCIS (Netherlands)

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

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

  8. A Roadmap for the Development of Alternative (Non-Animal) Methods for Systemic Toxicity Testing

    Science.gov (United States)

    Systemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new prod...

  9. Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxic Substances Control Act Test Submissions 2.0 (TSCATS 2.0) tracks the submissions of health and safety data submitted to the EPA either as required or...

  10. What Food and Feeding Rates are Optimum for the Chironomus dilutus Sediment Toxicity Test Method?

    Science.gov (United States)

    Laboratory tests with benthic macroinvertebrates are commonly used to assess the toxicity of both contaminated sediments and individual chemicals. Among the standard procedures for benthic macroinvertebrates are 10-d, 20-d, and life cycle exposures using the midge, Chironomus ...

  11. 40 CFR 797.1400 - Fish acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... appearance or physiology such as discoloration, excessive mucous production, hyperventilation, opaque eyes... delivery systems and test chambers should be cleaned before each test. They should be washed with detergent...

  12. 40 CFR 797.1300 - Daphnid acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... be exercised to introduce the daphnids below the surface of any solution to avoid trapping air under..., treatments, feeding history, acclimation procedures, and culture method. The age of the daphnids used in the..., the way the test was begun (e.g., conditioning, test chemical additions), the number of test organisms...

  13. The effect of repeated measurements and working memory on the most comfortable level in the ANL test.

    Science.gov (United States)

    Brännström, K Jonas; Olsen, Steen Østergaard; Holm, Lucas; Kastberg, Tobias; Ibertsson, Tina

    2014-11-01

    To study the effect of a large number of repetitions on the most comfortable level (MCL) when doing the acceptable noise level (ANL) test, and explore if MCL variability is related to central cognitive processes. Twelve MCL repetitions were measured within the ANL test using interleaved methodology during one session using a non-semantic version. Phonological (PWM) and visuospatial working memory (VSWM) was measured. Thirty-two normal-hearing adults. Repeated measures ANOVA, intraclass correlations, and the coefficient of repeatability (CR) were used to assess the repeatability. Repeated measures ANOVA and CR indicated poor agreement between the two first repetitions. After excluding the first repetition, analyses showed that the MCL in the ANL test is reliable. A negative association was found between PWM and MCL variability indicating that subjects with higher PWM show less variability. The findings suggest that, after excluding the first repetition, the MCL in the ANL test is reliable. A single repetition of the MCL in the ANL test should be avoided. If an interleaved methodology is used, a single ANL repetition should be added prior to the actual testing. The findings also suggest that MCL variability is associated to PWM but not VSWM.

  14. Predicting In Vivo Effect Levels for Repeat Dose Systemic Toxicity using Chemical, Biological, Kinetic and Study Covariates

    Science.gov (United States)

    In an effort to ensure chemical safety while reducing reliance on animal testing, USEPA and L’Oréal have collaborated to address a major challenge in chemical safety assessment using alternative approaches: the prediction of points-of-departure (POD) of systemic effects. Systemic...

  15. Aquatic toxicity testing of silver nanoparticles – a matter of timing

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Owsianiak, Mikolaj; Engelbrekt, Christian

    , and difficulties in controlling and/or describing the characteristics of the tested NPs. These issues may be related to the widespread approach of using freshly prepared stock solutions for ecotoxicity testing, as the introduction of NPs into aqueous media initiates time-dependent processes that possibly interfere...... of the test. Ultimately, the aim is better control of the AgNPs in the algal test system and improved prerequisites for describing their toxicity to alga. The underlying hypothesis is that a large part in the variability of AgNPs toxicity to algae can be explained by the kinetics of dissolution and speciation...... of Ag ions in the test media. To reduce the amount of time in which changes to NPs may occur during testing, the exposure period was minimized. A recently proposed short-term (2h) algal test was applied, using 14C incorporation during photosynthesis as toxic endpoint [1]. For citrate coated spherical Ag...

  16. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    Science.gov (United States)

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

  17. Alternative methods for toxicity assessments in fish: comparison of the fish embryo toxicity and the larval growth and survival tests in zebrafish and fathead minnows.

    Science.gov (United States)

    Jeffries, Marlo K Sellin; Stultz, Amy E; Smith, Austin W; Rawlings, Jane M; Belanger, Scott E; Oris, James T

    2014-11-01

    An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative, and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. In the present study, the performances of the FET test and the larval growth and survival (LGS; a standard toxicity testing method) test in zebrafish and fathead minnows were evaluated. This required that testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and that the performance of these testing strategies be evaluated by comparing the median lethal concentrations of 2 reference toxicants, 3,4-dicholoraniline and ammonia, obtained via each of the test types. The results showed that procedures for the zebrafish FET test can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for 3,4-dicholoraniline but not ammonia; therefore, conclusions regarding which test types offer the least or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and that further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy. © 2014 SETAC.

  18. On the possibility of using biological toxicity tests to monitor the work of wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Zorić Jelena

    2008-01-01

    Full Text Available The aim of this study was to ascertain the possibility of using biological toxicity tests to monitor influent and effluent wastewaters of wastewater treatment plants. The information obtained through these tests is used to prevent toxic pollutants from entering wastewater treatment plants and discharge of toxic pollutants into the recipient. Samples of wastewaters from the wastewater treatment plants of Kragujevac and Gornji Milanovac, as well as from the Lepenica and Despotovica Rivers immediately before and after the influx of wastewaters from the plants, were collected between October 2004 and June 2005. Used as the test organism in these tests was the zebrafish Brachydanio rerio Hamilton - Buchanon (Cyprinidae. The acute toxicity test of 96/h duration showed that the tested samples had a slight acutely toxic effect on B. rerio, except for the sample of influent wastewater into the Cvetojevac wastewater treatment plant, which had moderately acute toxicity, indicating that such water should be prevented from entering the system in order to eliminate its detrimental effect on the purification process.

  19. Field Validation of Toxicity Tests to Evaluate the Potential for Beneficial Use of Produced Water

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Bidwell; Jonathan Fisher; Naomi Cooper

    2008-03-31

    This study investigated potential biological effects of produced water contamination derived from occasional surface overflow and possible subsurface intrusion at an oil production site along the shore of Skiatook Lake, Oklahoma. We monitored basic chemistry and acute toxicity to a suite of standard aquatic test species (fathead minnow-Pimephales promelas, Daphnia pulex, Daphnia magna, and Ceriodaphnia dubia) in produced water and in samples taken from shallow groundwater wells on the site. Toxicity identification evaluations and ion toxicity modeling were used to identify toxic constituents in the samples. Lake sediment at the oil production site and at a reference site were also analyzed for brine intrusion chemically and by testing sediment toxicity using the benthic invertebrates, Chironomus dilutus, and Hyallela azteca. Sediment quality was also assessed with in situ survival and growth studies with H. azteca and the Asian clam, Corbicula fluminea, and by benthic macroinvertebrate community sampling. The produced water was acutely toxic to the aquatic test organisms at concentrations ranging from 1% to 10% of the whole produced water sample. Toxicity identification evaluation and ion toxicity modeling indicated major ion salts and hydrocarbons were the primary mixture toxicants. The standardized test species used in the laboratory bioassays exhibited differences in sensitivity to these two general classes of contaminants, which underscores the importance of using multiple species when evaluating produced water toxicity. Toxicity of groundwater was greater in samples from wells near a produced water injection well and an evaporation pond. Principle component analyses (PCA) of chemical data derived from the groundwater wells indicated dilution by lake water and possible biogeochemical reactions as factors that ameliorated groundwater toxicity. Elevated concentrations of major ions were found in pore water from lake sediments, but toxicity from these ions was

  20. Progress Toward Replacing Animals in Toxicity Testing for Cosmetics

    OpenAIRE

    Nye, Marisa B.

    2006-01-01

    In the 1980’s, animal rights activists successfully motivated the cosmetic industry to begin researching alternatives to animal tests. The European Union has taken action to stimulate development and validation of alternatives to animal testing through the Sixth and Seventh Amendments to the Cosmetics Directive. In this paper, I will briefly describe the history of the search for alternatives to animal testing for cosmetics. I will then discuss the progress that has been ma...

  1. Triage of Women with Low-Grade Cervical Lesions - HPV mRNA Testing versus Repeat Cytology

    Science.gov (United States)

    Sørbye, Sveinung Wergeland; Arbyn, Marc; Fismen, Silje; Gutteberg, Tore Jarl; Mortensen, Elin Synnøve

    2011-01-01

    Background In Norway, women with low-grade squamous intraepithelial lesions (LSIL) are followed up after six months in order to decide whether they should undergo further follow-up or be referred back to the screening interval of three years. A high specificity and positive predictive value (PPV) of the triage test is important to avoid unnecessary diagnostic and therapeutic procedures. Materials and Methods At the University Hospital of North Norway, repeat cytology and the HPV mRNA test PreTect HPV-Proofer, detecting E6/E7 mRNA from HPV types 16, 18, 31, 33 and 45, are used in triage of women with ASC-US and LSIL. In this study, women with LSIL cytology in the period 2005–2008 were included (n = 522). Two triage methods were evaluated in two separate groups: repeat cytology only (n = 225) and HPV mRNA testing in addition to repeat cytology (n = 297). Histologically confirmed cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) was used as the study endpoint. Results Of 522 women with LSIL, 207 had biopsies and 125 of them had CIN2+. The sensitivity and specificity of repeat cytology (ASC-US or worse) were 85.7% (95% confidence interval (CI): 72.1, 92.2) and 54.4 % (95% CI: 46.9, 61.9), respectively. The sensitivity and specificity of the HPV mRNA test were 94.2% (95% CI: 88.7, 99.7) and 86.0% (95% CI: 81.5, 90.5), respectively. The PPV of repeat cytology was 38.4% (95% CI: 29.9, 46.9) compared to 67.0% (95% CI: 57.7, 76.4) of the HPV mRNA test. Conclusion HPV mRNA testing was more sensitive and specific than repeat cytology in triage of women with LSIL cytology. In addition, the HPV mRNA test showed higher PPV. These data indicate that the HPV mRNA test is a better triage test for women with LSIL than repeat cytology. PMID:21918682

  2. Aquatic toxicity testing of liquid hydrophobic chemicals – Passive dosing exactly at the saturation limit

    DEFF Research Database (Denmark)

    Stibany, Felix; Nørgaard Schmidt, Stine; Schäffer, Andreas

    2017-01-01

    The aims of the present study were (1) to develop a passive dosing approach for aquatic toxicity testing of liquid substances with very high Kow values and (2) to apply this approach to the model substance dodecylbenzene (DDB, Log Kow = 8.65). The first step was to design a new passive dosing...... format for testing DDB exactly at its saturation limit. Silicone O-rings were saturated by direct immersion in pure liquid DDB, which resulted in swelling of >14%. These saturated O-rings were used to establish and maintain DDB exposure exactly at the saturation limit throughout 72-h algal growth...... at chemical activity of unity was higher than expected relative to a reported hydrophobicity cut-off in toxicity, but lower than expected relative to a reported chemical activity range for baseline toxicity. The present study introduces a new effective approach for toxicity testing of an important group...

  3. 40 CFR 797.1050 - Algal acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... chemical concentration that is calculated to effect X percent of the test criterion. (4) Growth means a... per volume of nutrient medium or test solution in a specified period of time. (5) Static system means... concentration may be pooled into one sample. An aliquot of the pooled sample may then be taken and the...

  4. 40 CFR 797.1330 - Daphnid chronic toxicity test.

    Science.gov (United States)

    2010-07-01

    ... daphnids below the surface of any solution so as not to trap air under the carapace. (vi) Acclimation. (A..., age, source, treatments, feeding history, acclimation procedures, and culture methods. The age of the... in the chambers, the way the test was begun (e.g., conditioning, test substance additions), the...

  5. 40 CFR 795.120 - Gammarid acute toxicity test.

    Science.gov (United States)

    2010-07-01

    ... chambers shall be covered loosely to reduce the loss of test solution or dilution water due to evaporation... holding tanks, acclimation tanks, and water supply systems, but they should be aged prior to use. Rubber... prodding. Flow-through means a continuous or an intermittent passage of test solution or dilution water...

  6. CAG repeat testing of androgen receptor polymorphism: is this necessary for the best clinical management of hypogonadism?

    Science.gov (United States)

    Francomano, Davide; Greco, Emanuela A; Lenzi, Andrea; Aversa, Antonio

    2013-10-01

    It is controversial whether or not testing the length of the androgen receptor polymorphism in clinical practice is useful for correct diagnosis and treatment of hypogonadism. To describe the molecular and clinical implications of testing the length of the androgen receptor polymorphism for treatment of hypogonadism in both male and female subjects. A systematic Medline search was conducted using several terms related to and including the terms "androgen receptor," "CAG-repeat polymorphism," "male hypogonadism," "female hypogonadism," and "neurodegenerative disease." Clinical evidence that demonstrates the importance of CAG repeat number investigation in male and female hypogonadism. A thorough review of the clinical utility of CAG repeat polymorphism investigation in men and women with hypogonadism is presented. The role of AR CAG repeat number investigation in hypogonadism (male and female) is not yet established in the clinical practice. In both sexes, a role during clinical management of hormonal replacement therapies may be hypothesized, but the CAG repeat number's relationship with the presence or absence of hypogonadal symptoms remains unclear. Pharmacogenomic investigations of the AR polymorphism may be a future option to tailor testosterone titration individually and to better identify subjects as potentially more or less responsive to treatments; also, investigation may be important to individually predict beneficial and side effects in special subpopulations, specifically, obese men and postmenopausal women. © 2013 International Society for Sexual Medicine.

  7. Toxicity assessment of sediments from three European river basins using a sediment contact test battery

    NARCIS (Netherlands)

    Tuikka, A.I.; Schmitt, C.; Hoess, S.; Bandow, N; von der Ohe, P.; de Zwart, D.; de Deckere, E.; Streck, G.; Mothes, S.; van Hattum, A.G.M.; Kocan, A.; Brix, R.; Brack, W.; Barcelo, D.; Sormunen, A.; Kukkonen, J.V.K.

    2011-01-01

    The toxicity of four polluted sediments and their corresponding reference sediments from three European river basins were investigated using a battery of six sediment contact tests representing three different trophic levels. The tests included were chronic tests with the oligochaete Lumbriculus

  8. Higher Drop in Speed during a Repeated Sprint Test in Soccer Players Reporting Former Hamstring Strain Injury

    Science.gov (United States)

    Røksund, Ola D.; Kristoffersen, Morten; Bogen, Bård E.; Wisnes, Alexander; Engeseth, Merete S.; Nilsen, Ann-Kristin; Iversen, Vegard V.; Mæland, Silje; Gundersen, Hilde

    2017-01-01

    Aim: Hamstring strain injury is common in soccer. The aim of this study was to evaluate the physical capacity of players who have and have not suffered from hamstring strain injury in a sample of semi-professional and professional Norwegian soccer players in order to evaluate characteristics and to identify possible indications of insufficient rehabilitation. Method: Seventy-five semi-professional and professional soccer players (19 ± 3 years) playing at the second and third level in the Norwegian league participated in the study. All players answered a questionnaire, including one question about hamstring strain injury (yes/no) during the previous 2 years. They also performed a 40 m maximal sprint test, a repeated sprint test (8 × 20 m), a countermovement jump, a maximal oxygen consumption (VO2max) test, strength tests and flexibility tests. Independent sample t-tests were used to evaluate differences in the physical capacity of the players who had suffered from hamstring strain injury and those who had not. Mixed between-within subject's analyses of variance was used to compare changes in speed during the repeated sprint test between groups. Results: Players who reported hamstring strain injury during the previous two years (16%) had a significantly higher drop in speed (0.07 vs. 0.02 s, p = 0.007) during the repeated sprint test, compared to players reporting no previous hamstring strain injury. In addition, there was a significant interaction (groups × time) (F = 3.22, p = 0.002), showing that speed in the two groups changed differently during the repeated sprint test. There were no significant differences in relations to age, weight, height, body fat, linear speed, countermovement jump height, leg strength, VO2max, or hamstring flexibility between the groups. Conclusion: Soccer players who reported hamstring strain injury during the previous 2 years showed significant higher drop in speed during the repeated sprint test compared to players with no hamstring

  9. Development of Cardiovascular and Neurodevelopmental Metrics as Sublethal Endpoints for the Fish Embryo Toxicity Test.

    Science.gov (United States)

    Krzykwa, Julie C; Olivas, Alexis; Jeffries, Marlo K Sellin

    2018-06-19

    The fathead minnow fish embryo toxicity (FET) test has been proposed as a more humane alternative to current toxicity testing methods, as younger organisms are thought to experience less distress during toxicant exposure. However, the FET test protocol does not include endpoints that allow for the prediction of sublethal adverse outcomes, limiting its utility relative to other test types. Researchers have proposed the development of sublethal endpoints for the FET test to increase its utility. The present study 1) developed methods for previously unmeasured sublethal metrics in fathead minnows (i.e., spontaneous contraction frequency and heart rate) and 2) investigated the responsiveness of several sublethal endpoints related to growth (wet weight, length, and growth-related gene expression), neurodevelopment (spontaneous contraction frequency, and neurodevelopmental gene expression), and cardiovascular function and development (pericardial area, eye size and cardiovascular related gene expression) as additional FET test metrics using the model toxicant 3,4-dichloroaniline. Of the growth, neurological and cardiovascular endpoints measured, length, eye size and pericardial area were found to more responsive than the other endpoints, respectively. Future studies linking alterations in these endpoints to longer-term adverse impacts are needed to fully evaluate the predictive power of these metrics in chemical and whole effluent toxicity testing. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Test-retest repeatability of child's respiratory symptoms and perceived indoor air quality - comparing self- and parent-administered questionnaires.

    Science.gov (United States)

    Lampi, Jussi; Ung-Lanki, Sari; Santalahti, Päivi; Pekkanen, Juha

    2018-02-09

    Questionnaires can be used to assess perceived indoor air quality and symptoms in schools. Questionnaires for primary school aged children have traditionally been parent-administered, but self-administered questionnaires would be easier to administer and may yield as good, if not better, information. Our aim was to compare the repeatability of self- and parent-administered indoor air questionnaires designed for primary school aged pupils. Indoor air questionnaire with questions on child's symptoms and perceived indoor air quality in schools was sent to parents of pupils aged 7-12 years in two schools and again after two weeks. Slightly modified version of the questionnaire was administered to pupils aged 9-12 years in another two schools and repeated after a week. 351 (52%) parents and 319 pupils (86%) answered both the first and the second questionnaire. Test-retest repeatability was assessed with intra-class correlation (ICC) and Cohen's kappa coefficients (k). Test-retest repeatability was generally between 0.4-0.7 (ICC; k) in both self- and parent-administered questionnaire. In majority of the questions on symptoms and perceived indoor air quality test-retest repeatability was at the same level or slightly better in self-administered compared to parent-administered questionnaire. Agreement of self- and parent administered questionnaires was generally indoor air quality. Children aged 9-12 years can give as, or even more, repeatable information about their respiratory symptoms and perceived indoor air quality than their parents. Therefore, it may be possible to use self-administered questionnaires in future studies also with children.

  11. Recreating the seawater mixture composition of HOCs in toxicity tests with Artemia franciscana by passive dosing

    Energy Technology Data Exchange (ETDEWEB)

    Rojo-Nieto, E., E-mail: elisa.rojo@uca.es [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Smith, K.E.C. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark); Perales, J.A. [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Mayer, P. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark)

    2012-09-15

    The toxicity testing of hydrophobic organic compounds (HOCs) in aquatic media is generally challenging, and this is even more problematic for mixtures. The hydrophobic properties of these compounds make them difficult to dissolve, and subsequently to maintain constant exposure concentrations. Evaporative and sorptive losses are highly compound-specific, which can alter not only total concentrations, but also the proportions between the compounds in the mixture. Therefore, the general aim of this study was to explore the potential of passive dosing for testing the toxicity of a PAH mixture that recreates the mixture composition found in seawater from a coastal area of Spain, the Bay of Algeciras. First, solvent spiking and passive dosing were compared for their suitability to determine the acute toxicity to Artemia franciscana nauplii of several PAHs at their respective solubility limits. Second, passive dosing was applied to recreate the seawater mixture composition of PAHs measured in a Spanish monitoring program, to test the toxicity of this mixture at different levels. HPLC analysis was used to confirm the reproducibility of the dissolved exposure concentrations for the individual PAHs and mixtures. This study shows that passive dosing has some important benefits in comparison with solvent spiking for testing HOCs in aquatic media. These include maintaining constant exposure concentrations, leading to higher reproducibility and a relative increase in toxicity. Passive dosing is also able to faithfully reproduce real mixtures of HOCs such as PAHs, in toxicity tests, reproducing both the levels and proportions of the different compounds. This provides a useful approach for studying the toxicity of environmental mixtures of HOCs, both with a view to investigating their toxicity but also for determining safety factors before such mixtures result in detrimental effects.

  12. Evaluation of natural toxicity on MICROTOX solid-phase test. The pelitic normalization

    International Nuclear Information System (INIS)

    Onorati, F.; Pellegrini, D.; Ausili, A.

    1999-01-01

    In sediment toxicity testing Microtox solid-phase test (SPT) is one of the most used and standardised bioassay. Nevertheless, its real sensitivity and discriminatory power is still unclear, because of several interferences principally related to the matrix composition. Using reference sediments, characterised with chemical and physical analysis, it was possible to find a significant relationship between their natural toxicity and the pelitic fraction that allows to estimate the natural component of the acute toxicity in contaminated samples. This relationship arrows a more sensitive and valid interpretation than raw data and it is used to develop a sediment toxicity index (STI) based on radio to reference (RTR) concept, applicable to harbour contaminated samples [it

  13. Controlling silver nanoparticle exposure in algal toxicity testing - A matter of timing

    DEFF Research Database (Denmark)

    Sørensen, Sara Nørgaard; Baun, Anders

    2015-01-01

    ) in a standard algal growth inhibition test (ISO 8692:2004) for 48 h and a short-term (2 h) 14C-assimilation test. For AgNO3, similar responses were obtained in the two tests, whereas freshly prepared suspensions of citrate stabilized AgNPs were less toxic in the 2-h tests compared to the 48-h tests. The 2-h...... test was found applicable for dissolved silver, but yielded non-monotonous concentration–response relationships and poor reproducibility for freshly prepared AgNP suspensions. However, when aging AgNPs in algal medium 24 h prior to testing, clear concentration–response patterns emerged...... and reproducibility increased. Prolonged aging to 48 h increased toxicity in the 2-h tests whereas aging beyond 48 h reduced toxicity. Our results demonstrate that the outcome of algal toxicity testing of AgNPs is highly influenced not only by the test duration, but also by the time passed from the moment Ag...

  14. Alternative approaches for identifying acute systemic toxicity: Moving from research to regulatory testing.

    Science.gov (United States)

    Hamm, Jon; Sullivan, Kristie; Clippinger, Amy J; Strickland, Judy; Bell, Shannon; Bhhatarai, Barun; Blaauboer, Bas; Casey, Warren; Dorman, David; Forsby, Anna; Garcia-Reyero, Natàlia; Gehen, Sean; Graepel, Rabea; Hotchkiss, Jon; Lowit, Anna; Matheson, Joanna; Reaves, Elissa; Scarano, Louis; Sprankle, Catherine; Tunkel, Jay; Wilson, Dan; Xia, Menghang; Zhu, Hao; Allen, David

    2017-06-01

    Acute systemic toxicity testing provides the basis for hazard labeling and risk management of chemicals. A number of international efforts have been directed at identifying non-animal alternatives for in vivo acute systemic toxicity tests. A September 2015 workshop, Alternative Approaches for Identifying Acute Systemic Toxicity: Moving from Research to Regulatory Testing, reviewed the state-of-the-science of non-animal alternatives for this testing and explored ways to facilitate implementation of alternatives. Workshop attendees included representatives from international regulatory agencies, academia, nongovernmental organizations, and industry. Resources identified as necessary for meaningful progress in implementing alternatives included compiling and making available high-quality reference data, training on use and interpretation of in vitro and in silico approaches, and global harmonization of testing requirements. Attendees particularly noted the need to characterize variability in reference data to evaluate new approaches. They also noted the importance of understanding the mechanisms of acute toxicity, which could be facilitated by the development of adverse outcome pathways. Workshop breakout groups explored different approaches to reducing or replacing animal use for acute toxicity testing, with each group crafting a roadmap and strategy to accomplish near-term progress. The workshop steering committee has organized efforts to implement the recommendations of the workshop participants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Visual attention to repeated print advertising : A test of scanpath theory

    NARCIS (Netherlands)

    Pieters, F.G.M.; Rosbergen, E.; Wedel, M.

    The authors examine consumers' visual attention during repeated exposures to print advertisements using eye-tracking methodology. The authors propose a statistical model comprising submodels for two key measures of visual attention to elements of the advertisement: attention duration and inter- and

  16. Visual attention to repeated print advertising : A test of scanpath theory

    NARCIS (Netherlands)

    Pieters, F.G.M.; Rosbergen, E.; Wedel, M.

    1999-01-01

    The authors examine consumers' visual attention during repeated exposures to print advertisements using eye-tracking methodology. The authors propose a statistical model comprising submodels for two key measures of visual attention to elements of the advertisement: attention duration and inter- and

  17. The Dark Side of Testing Memory: Repeated Retrieval Can Enhance Eyewitness Suggestibility

    Science.gov (United States)

    Chan, Jason C. K.; LaPaglia, Jessica A.

    2011-01-01

    Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed…

  18. Cross-trimester repeated measures testing for Down's syndrome screening: an assessment.

    LENUS (Irish Health Repository)

    Wright, D

    2010-07-01

    To provide estimates and confidence intervals for the performance (detection and false-positive rates) of screening for Down\\'s syndrome using repeated measures of biochemical markers from first and second trimester maternal serum samples taken from the same woman.

  19. Digital holographic microscopy for toxicity testing and cell culture quality control

    Science.gov (United States)

    Kemper, Björn

    2018-02-01

    For the example of digital holographic microscopy (DHM), it is illustrated how label-free biophysical parameter sets can be extracted from quantitative phase images of adherent and suspended cells, and how the retrieved data can be applied for in-vitro toxicity testing and cell culture quality assessment. This includes results from the quantification of the reactions of cells to toxic substances as well as data from sophisticated monitoring of cell alterations that are related to changes of cell culture conditions.

  20. Design and Analysis of Chronic Aquatic Tests of Toxicity with Daphnia magna.

    Science.gov (United States)

    1981-12-01

    surface waters. From that need evolved numerous standard toxicity tests. Aquatic toxicologists and biologists developed, refine,, and standard- ized many...experimental categorization summary sheets prepared by Dr. William van der Schalie, which is shown in Table I.I. 7 j-. " .’?, i...partial solution to this dilema can be obtained by studying the effects of the solvent alone. If the solvent by itself produces no toxic responses at

  1. Evaluation of 90-day Repeated Dose Oral Toxicity, Glycometabolism, Learning and Memory Ability, and Related Enzyme of Chromium Malate Supplementation in Sprague-Dawley Rats.

    Science.gov (United States)

    Feng, Weiwei; Wu, Huiyu; Li, Qian; Zhou, Zhaoxiang; Chen, Yao; Zhao, Ting; Feng, Yun; Mao, Guanghua; Li, Fang; Yang, Liuqing; Wu, Xiangyang

    2015-11-01

    Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the 90-day oral toxicity of chromium malate in Sprague-Dawley rats. The present study inspected the effect of chromium malate on glycometabolism, glycometabolism-related enzymes, lipid metabolism, and learning and memory ability in metabolically healthy Sprague-Dawley rats. The results showed that all rats survived and pathological, toxic, feces, and urine changes were not observed. Chromium malate did not cause measurable damage on liver, brain, and kidney. The fasting blood glucose, serum insulin, insulin resistance index, C-peptide, hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride levels of normal rats in chromium malate groups had no significant change when compared with control group and chromium picolinate group under physiologically relevant conditions. The serum and organ content of Cr in chromium malate groups had no significant change compared with control group. No significant changes were found in morris water maze test and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and true choline esterase (TChE) activity. The results indicated that supplementation with chromium malate did not cause measurable toxicity and has no obvious effect on glycometabolism and related enzymes, learning and memory ability, and related enzymes and lipid metabolism of female and male rats. The results of this study suggest that chromium malate is safe for human consumption.

  2. How to prepare water accommodated fractions from petroleum hydrocarbons for use in aquatic toxicity testing - the basics

    International Nuclear Information System (INIS)

    Blenkinsopp, S.; Boileau, P.; Kyle, D.; Sergy, G.; Fingas, M.

    1996-01-01

    A method to prepare water accommodated fractions (WAFs) from petroleum products for use in toxicity testing, was introduced. In order to develop a repeatable protocol, a systematic study of a range of experimental variables was conducted. One semi-solid oil and six liquid oils were exposed to artificial seawater. Studies were also performed on three liquid oils exposed to freshwater. Low energy mixing and fluorinated Nalgene carboys was used to produce the WAFs. The mixing time depended on the oil type and loading rate. Individual loading rates were prepared for each concentration, because WAF composition is influenced by loading rate rather than serial dilution. An overview of the basic concepts of WAF preparation was described. A draft protocol for preparing WAFs from liquid and semi-solid oil was also described and results were summarized. 5 refs., 3 tabs., 6 figs

  3. NMSBA: Aken Technologies Final Report: Toxicity Testing of Liquidoff

    Energy Technology Data Exchange (ETDEWEB)

    Ruffing, Anne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jensen, Travis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Strickland, Lucas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    To determine the effect of Liquidoff on bacteria, three bacterial strains were tested: Escherichia coli DH5α, Synechococcus sp. PCC 7002, and Synechococcus elongatus PCC 7942. E. coli DH5α is a Gram-negative, aerobic bacterium that is often found in normal gut flora and is commonly used the laboratory due to its fast growth rate. Synechococcus sp. PCC 7002 and S. elongatus PCC 7942 are Gram-negative, aquatic, autophototrophic cyanobacteria. Synechococcus sp. PCC 7002 is a marine cyanobacterium isolated from ‘fish pens’ on Magueyes Island, Puerto Rico in 1962, while S. elongatus PCC 7942 is a freshwater cyanobacterium. It should be noted that no Gram-positive bacterium was tested in this study.

  4. Development of a Chronic Toxicity Testing Method for Daphnia pulex

    Science.gov (United States)

    2015-08-01

    survivorship) and sublethal endpoints (e.g., growth, reproduction) and are in concept more sensitive than acute lethality tests. • Control– negative ...organism is unable to swim /move after gentle agitation with a transfer pipette but is still alive • LC50-Lethal concentration at which a median effect on...from Zumwalt et al. (1994) The original apparatus uses water splitting channels to perform water changes on 8 beakers at once; the modified apparatus

  5. Relating results from earthworm toxicity tests to agricultural soil

    Science.gov (United States)

    Beyer, W.N.; Greig-Smith, P.W.

    1992-01-01

    The artificial soil tests of the European Economic Community and of the Organization for Economic Cooperation produce data relating earthworm mortality to pesticide concentrations in soil under laboratory conditions. To apply these results to agricultural soils it is necessary to relate these concentrations to amounts of pesticide applied per area. This paper reviews the relevant published literature and suggests a simple relation for regulatory use. Hazards to earthworms from pesticides are suggested to be greatest soon after application, when the pesticides may be concentrated in a soil layer a few millimeters thick. For estimating exposure of earthworms, however, a thicker soil layer should be considered, to account for their movement through soil. During favorable weather conditions, earthworms belonging to species appropriate to the artificial soil test have been reported to confine their activity to a layer about 5 cm. If a 5-cm layer is accepted as relevant for regulatory purposes, then an application of 1 kg/ha would be equivalent to 1-67 ppm (dry) in the artificial soil test.

  6. Animal Testing for Acute Inhalation Toxicity: A Thing of the Past?

    DEFF Research Database (Denmark)

    Da Silva, Emilie; Sørli, Jorid Birkelund

    2018-01-01

    According to REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals), testing for acute inhalation toxicity is required for chemicals manufactured or imported at tonnages ≥ 10 tons per year. Three OECD test guidelines for acute inhalation toxicity in vivo are adopted (TG 403......, TG 436, and TG 433). Since animal testing is ethically, scientifically and economically questionable, adoption of alternative methods by the European Union and the OECD is needed. An in vitro system based on the study of lung surfactant function is introduced....

  7. Toxic Substances Control Act test submissions database (TSCATS) - comprehensive update. Data file

    International Nuclear Information System (INIS)

    1993-01-01

    The Toxic Substances Control Act Test Submissions Database (TSCATS) was developed to make unpublished test data available to the public. The test data is submitted to the U.S. Environmental Protection Agency by industry under the Toxic Substances Control Act. Test is broadly defined to include case reports, episodic incidents, such as spills, and formal test study presentations. The database allows searching of test submissions according to specific chemical identity or type of study when used with an appropriate search retrieval software program. Studies are indexed under three broad subject areas: health effects, environmental effects and environmental fate. Additional controlled vocabulary terms are assigned which describe the experimental protocol and test observations. Records identify reference information needed to locate the source document, as well as the submitting organization and reason for submission of the test data

  8. An Audit of Repeat Testing at an Academic Medical Center: Consistency of Order Patterns With Recommendations and Potential Cost Savings.

    Science.gov (United States)

    Hueth, Kyle D; Jackson, Brian R; Schmidt, Robert L

    2018-05-31

    To evaluate the prevalence of potentially unnecessary repeat testing (PURT) and the associated economic burden for an inpatient population at a large academic medical facility. We evaluated all inpatient test orders during 2016 for PURT by comparing the intertest times to published recommendations. Potential cost savings were estimated using the Centers for Medicare & Medicaid Services maximum allowable reimbursement rate. We evaluated result positivity as a determinant of PURT through logistic regression. Of the evaluated 4,242 repeated target tests, 1,849 (44%) were identified as PURT, representing an estimated cost-savings opportunity of $37,376. Collectively, the association of result positivity and PURT was statistically significant (relative risk, 1.2; 95% confidence interval, 1.1-1.3; P < .001). PURT contributes to unnecessary health care costs. We found that a small percentage of providers account for the majority of PURT, and PURT is positively associated with result positivity.

  9. Toward toxicity testing of nanomaterials in the 21st century: a paradigm for moving forward.

    Science.gov (United States)

    Lai, David Y

    2012-01-01

    A challenge-facing hazard identification and safety evaluation of engineered nanomaterials being introduced to market is the diversity and complexity of the types of materials with varying physicochemical properties, many of which can affect their toxicity by different mechanisms. In general, in vitro test systems have limited usefulness for hazard identification of nanoparticles due to various issues. Meanwhile, conducting chronic toxicity/carcinogenicity studies in rodents for every new nanomaterial introduced into the commerce is impractical if not impossible. New toxicity testing systems which rely on predictive, high-throughput technologies may be the ultimate goal of evaluating the potential hazard of nanomaterials. However, at present, this approach alone is unlikely to succeed in evaluating the toxicity of the wide array of nanomaterials and requires validation from in vivo studies. This article proposes a paradigm for toxicity testing and elucidation of the molecular mechanisms of reference materials for specific nanomaterial classes/subclasses using short-term in vivo animal studies in conjunction with high-throughput screenings and mechanism-based short-term in vitro assays. The hazard potential of a particular nanomaterial can be evaluated by conducting only in vitro high-throughput assays and mechanistic studies and comparing the data with those of the reference materials in the specific class/subclass-an approach in line with the vision for 'Toxicity Testing in the 21st Century' of chemicals. With well-designed experiments, testing nanomaterials of varying/selected physicochemical parameters may be able to identify the physicochemical parameters contributing to toxicity. The data so derived could be used for the development of computer model systems to predict the hazard potential of specific nanoparticles based on property-activity relationships. Copyright © 2011 John Wiley & Sons, Inc.

  10. Acute and chronic aquatic toxicity of aromatic extracts. Summary of relevant test data

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.; Djemel, N.; Eadsforth, C.V.; King, D.; Parkerton, T.; Leon Paumen, M.; Dmytrasz, B.; Del Castillo, F.

    2013-09-15

    This report describes the experimental procedures and the results obtained in acute and chronic ecotoxicity tests on several aromatic extracts samples. The samples were tested for toxicity to the rainbow trout (Oncorhynchus mykiss), the crustacean zooplankter, Daphnia magna and the algae, Selenastrum capricornutum using water accommodated fractions. These results assist in determining the environmental hazard posed by aromatic extracts.

  11. Acute aquatic toxicity of heavy fuel oils. Summary of relevant test data

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.; Djemel, N.; Eadsforth, C.V.; King, D.; Parkerton, T.; Paumen, M.L.; Dmytrasz, B.

    2011-12-15

    This report describes the experimental procedures and results obtained in acute ecotoxicity tests on several heavy fuel oil (HFO) samples. Water accommodated fractions (WAFs) of these samples were tested for toxicity to the rainbow trout (Oncorhynchus mykiss), the crustacean zooplankter (Daphnia magna) and green algae (Selenastrum capricornutum). These results assist in determining the environmental hazard from heavy fuel oil.

  12. Interpreting in vitro developmental toxicity test battery results: The consideration of toxicokinetics

    NARCIS (Netherlands)

    Bosgra, S.; Westerhout, J.

    2015-01-01

    In the EU collaborative project ChemScreen an alternative, in vitro assay-based test strategy was developed to screen compounds for reproductive toxicity. A toxicokinetic modeling approach was used to allow quantitative comparison between effective concentrations in the in vitro test battery and

  13. Evaluation of an alternative in vitro test battery for detecting reproductive toxicants in a grouping context

    NARCIS (Netherlands)

    Kroese, E.D.; Bosgra, S.; Buist, H.E.; Lewin, G.; Linden, S.C. van der; Man, H.Y.; Piersma, A.H.; Rorije, E.; Schulpen, S.H.W.; Schwarz, M.; Uibel, F.; Vugt-Lussenburg, B.M.A. van; Wolterbeek, A.P.M.; Burg, B. van der

    2015-01-01

    Previously we showed a battery consisting of CALUX transcriptional activation assays, the ReProGlo assay, and the embryonic stem cell test, and zebrafish embryotoxicity assay as 'apical' tests to correctly predict developmental toxicity for 11 out of 12 compounds, and to explain the one false

  14. Development of an alternative artificial soil for earthworm toxicity testing in tropical countries.

    NARCIS (Netherlands)

    de Silva, M.; van Gestel, C.A.M.

    2009-01-01

    The standard soil invertebrate toxicity tests developed by OECD and ISO use an artificial soil as the test substrate, which contains sphagnum peat as a component. This type of peat is not widely available. Investigation of possible alternative substrates using locally available materials therefore

  15. Large Dataset of Acute Oral Toxicity Data Created for Testing in Silico Models (ASCCT meeting)

    Science.gov (United States)

    Acute toxicity data is a common requirement for substance registration in the US. Currently only data derived from animal tests are accepted by regulatory agencies, and the standard in vivo tests use lethality as the endpoint. Non-animal alternatives such as in silico models are ...

  16. Acute aquatic toxicity of heavy fuel oils. Summary of relevant test data

    International Nuclear Information System (INIS)

    Comber, M.I.H.; Den Haan, K.; Djemel, N.; Eadsforth, C.V.; King, D.; Parkerton, T.; Paumen, M.L.; Dmytrasz, B.

    2011-12-01

    This report describes the experimental procedures and results obtained in acute ecotoxicity tests on several heavy fuel oil (HFO) samples. Water accommodated fractions (WAFs) of these samples were tested for toxicity to the rainbow trout (Oncorhynchus mykiss), the crustacean zooplankter (Daphnia magna) and green algae (Selenastrum capricornutum). These results assist in determining the environmental hazard from heavy fuel oil.

  17. Using biodynamic models to reconcile differences between laboratory toxicity tests and field biomonitoring with aquatic insects

    Science.gov (United States)

    Buchwalter, D.B.; Cain, D.J.; Clements, W.H.; Luoma, S.N.

    2007-01-01

    Aquatic insects often dominate lotic ecosystems, yet these organisms are under-represented in trace metal toxicity databases. Furthermore, toxicity data for aquatic insects do not appear to reflect their actual sensitivities to metals in nature, because the concentrations required to elicit toxicity in the laboratory are considerably higher than those found to impact insect communities in the field. New approaches are therefore needed to better understand how and why insects are differentially susceptible to metal exposures. Biodynamic modeling is a powerful tool for understanding interspecific differences in trace metal bioaccumulation. Because bioaccumulation alone does not necessarily correlate with toxicity, we combined biokinetic parameters associated with dissolved cadmium exposures with studies of the subcellular compartmentalization of accumulated Cd. This combination of physiological traits allowed us to make predictions of susceptibility differences to dissolved Cd in three aquatic insect taxa: Ephemerella excrucians, Rhithrogena morrisoni, and Rhyacophila sp. We compared these predictions with long-term field monitoring data and toxicity tests with closely related taxa: Ephemerella infrequens, Rhithrogena hageni, and Rhyacophila brunea. Kinetic parameters allowed us to estimate steady-state concentrations, the time required to reach steady state, and the concentrations of Cd projected to be in potentially toxic compartments for different species. Species-specific physiological traits identified using biodynamic models provided a means for better understanding why toxicity assays with insects have failed to provide meaningful estimates for metal concentrations that would be expected to be protective in nature. ?? 2007 American Chemical Society.

  18. Repeated rat-forced swim test: reducing the number of animals to evaluate gradual effects of antidepressants.

    Science.gov (United States)

    Mezadri, T J; Batista, G M; Portes, A C; Marino-Neto, J; Lino-de-Oliveira, C

    2011-02-15

    The forced swim test (FST) is a pre-clinical test to short and long term treatment with antidepressant drugs (ADT), which requires between-subject designs. Herein a modified protocol of the FST using within-subject design (repeated rat-FST) was evaluated. Male Wistar rats were submitted to 15 min of swimming (Day 1: pretest) followed by three subsequent 5 min-swimming tests one week apart (Day 2: test, Day 7: retest 1, Day 14: retest 2). To determine the temporal and factorial characteristics of the variables scored in the repeated rat-FST, the protocol was carried out in untreated animals (E1). To validate the method, daily injections of Fluoxetine (FLX, 2.5mg/kg, i.p.) or saline were given over a 2-week period (E2). Tests and retests have been videotaped for further register of the latency, frequency and duration of behaviors. Over retesting the latency to immobility decreased whereas duration of immobility tended to increase. Factorial analysis revealed that the test, the retest 1 as well as the retest 2 have variables suitable to detection of antidepressant-like effects of ADT. Compared to saline, FLX chronically administrated reduced duration of immobility whereas increased duration of swimming in retest 2. The data suggest that repeated rat-FST detected the gradual increase in the efficacy of low doses of FLX over time. Therefore, repeated rat-FST seemed suitable to detect short and long term effects of selective serotonin reuptake inhibitors, or other ADT, thus reducing the number of animals used in the screenings of this type of compounds. © 2010 Elsevier B.V. All rights reserved.

  19. Consensus report on the future of animal-free systemic toxicity testing

    OpenAIRE

    Leist, Marcel; Hasiwa, Nina; Rovida, Costanza; Daneshian, Mardas; Basketter, David; Kimber, Ian; Clewell, Harvey; Gocht, Tilman; Goldberg, Alan; Busquet, Francois; Rossi, Anna-Maria; Schwarz, Michael; Stephens, Martin; Taalman, Rob; Knudsen, Thomas B

    2014-01-01

    Since March 2013, animal use for cosmetics testing for the European market has been banned. This requires a renewed view on risk assessment in this field. However, in other fields as well, traditional animal experimentation does not always satisfy requirements in safety testing, as the need for human-relevant information is ever increasing. A general strategy for animal-free test approaches was outlined by the US National Research Council`s vision document for Toxicity Testing in the 21st Cen...

  20. Reduction and technical simplification of testing protocol for walking based on repeatability analyses: An Interreg IVa pilot study

    Directory of Open Access Journals (Sweden)

    Nejc Sarabon

    2010-12-01

    Full Text Available The aim of this study was to define the most appropriate gait measurement protocols to be used in our future studies in the Mobility in Ageing project. A group of young healthy volunteers took part in the study. Each subject carried out a 10-metre walking test at five different speeds (preferred, very slow, very fast, slow, and fast. Each walking speed was repeated three times, making a total of 15 trials which were carried out in a random order. Each trial was simultaneously analysed by three observers using three different technical approaches: a stop watch, photo cells and electronic kinematic dress. In analysing the repeatability of the trials, the results showed that of the five self-selected walking speeds, three of them (preferred, very fast, and very slow had a significantly higher repeatability of the average walking velocity, step length and cadence than the other two speeds. Additionally, the data showed that one of the three technical methods for gait assessment has better metric characteristics than the other two. In conclusion, based on repeatability, technical and organizational simplification, this study helped us to successfully define a simple and reliable walking test to be used in the main study of the project.

  1. Human epidermal growth factor receptor 2 testing in invasive breast cancer: should histological grade, type and oestrogen receptor status influence the decision to repeat testing?

    Science.gov (United States)

    Rakha, Emad A; Pigera, Marian; Shin, Sandra J; D'Alfonso, Timothy; Ellis, Ian O; Lee, Andrew H S

    2016-07-01

    The recent American Society of Clinical Oncology/College of American Pathologists guidelines for human epidermal growth factor receptor 2 (HER2) testing in breast cancer recommend repeat testing based on tumour grade, tumour type, and hormone receptor status. The aim of this study was to test the value of these criteria. HER2 status was concordant in the core biopsies and excision specimens in 392 of 400 invasive carcinomas. The major reasons for discordance were amplification around the cut-off for positivity and tumour heterogeneity. Of 116 grade 3 carcinomas that were HER2-negative in the core biopsy, four were HER2-positive in the excision specimen. Three of these four either showed borderline negative amplification in the core biopsy or were heterogeneous. None of the 55 grade 1 carcinomas were HER2-positive. Review of repeat testing of HER2 in routine practice suggested that it may also be of value for multifocal tumours and if recommended by the person assessing the in-situ hybridization. Mandatory repeat HER2 testing of grade 3 HER2-negative carcinomas is not appropriate. This is particularly true if repeat testing is performed after borderline negative amplification in the core biopsy or in HER2-negative heterogeneous carcinomas. © 2015 John Wiley & Sons Ltd.

  2. Effect of e-Learning and Repeated Performance Feedback on Spirometry Test Quality in Family Practice: A Cluster Trial

    Science.gov (United States)

    Schermer, Tjard R.; Akkermans, Reinier P.; Crockett, Alan J.; van Montfort, Marian; Grootens-Stekelenburg, Joke; Stout, Jim W.; Pieters, Willem

    2011-01-01

    PURPOSE Spirometry has become an indispensable tool in primary care to exclude, diagnose, and monitor chronic respiratory conditions, but the quality of spirometry tests in family practices is a reason for concern. Aim of this study was to investigate whether a combination of e-learning and bimonthly performance feedback would improve spirometry test quality in family practices in the course of 1 year. METHODS Our study was a cluster trial with 19 family practices allocated to intervention or control conditions through minimization. Intervention consisted of e-learning and bimonthly feedback reports to practice nurses. Control practices received only the joint baseline workshop. Spirometry quality was assessed by independent lung function technicians. Two outcomes were defined, with the difference between rates of tests with 2 acceptable and repeatable blows being the primary outcome and the difference between rates of tests with 2 acceptable blows being the secondary outcome. We used multilevel logistic regression analysis to calculate odds ratios (ORs) for an adequate test in intervention group practices. RESULTS We analyzed 1,135 tests. Rate of adequate tests was 33% in intervention and 30% in control group practices (OR = 1.3; P=.605). Adequacy of tests did not differ between groups but tended to increase with time: OR = 2.2 (P = .057) after 3 and OR = 2.0 (P = .086) in intervention group practices after 4 feedback reports. When ignoring test repeatability, these differences between the groups were slightly more pronounced: OR = 2.4 (P = .033) after 3 and OR=2.2 (P = .051) after 4 feedback reports. CONCLUSIONS In the course of 1 year, we observed a small and late effect of e-learning and repeated feedback on the quality of spirometry as performed by family practice nurses. This intervention does not seem to compensate the lack of rigorous training and experience in performing spirometry tests in most practices. PMID:21747104

  3. Effect of e-learning and repeated performance feedback on spirometry test quality in family practice: a cluster trial.

    Science.gov (United States)

    Schermer, Tjard R; Akkermans, Reinier P; Crockett, Alan J; van Montfort, Marian; Grootens-Stekelenburg, Joke; Stout, Jim W; Pieters, Willem

    2011-01-01

    Spirometry has become an indispensable tool in primary care to exclude, diagnose, and monitor chronic respiratory conditions, but the quality of spirometry tests in family practices is a reason for concern. Aim of this study was to investigate whether a combination of e-learning and bimonthly performance feedback would improve spirometry test quality in family practices in the course of 1 year. Our study was a cluster trial with 19 family practices allocated to intervention or control conditions through minimization. Intervention consisted of e-learning and bimonthly feedback reports to practice nurses. Control practices received only the joint baseline workshop. Spirometry quality was assessed by independent lung function technicians. Two outcomes were defined, with the difference between rates of tests with 2 acceptable and repeatable blows being the primary outcome and the difference between rates of tests with 2 acceptable blows being the secondary outcome. We used multilevel logistic regression analysis to calculate odds ratios (ORs) for an adequate test in intervention group practices. We analyzed 1,135 tests. Rate of adequate tests was 33% in intervention and 30% in control group practices (OR = 1.3; P=.605). Adequacy of tests did not differ between groups but tended to increase with time: OR = 2.2 (P = .057) after 3 and OR = 2.0 (P = .086) in intervention group practices after 4 feedback reports. When ignoring test repeatability, these differences between the groups were slightly more pronounced: OR = 2.4 (P = .033) after 3 and OR=2.2 (P = .051) after 4 feedback reports. In the course of 1 year, we observed a small and late effect of e-learning and repeated feedback on the quality of spirometry as performed by family practice nurses. This intervention does not seem to compensate the lack of rigorous training and experience in performing spirometry tests in most practices.

  4. Deployment Repeatability

    Science.gov (United States)

    2016-08-31

    large cohort of trials to spot unusual cases. However, deployment repeatability is inherently a nonlinear phenomenon, which makes modeling difficult...and GEMS tip position were both tracked during ground testing by a laser target tracking system. Earlier SAILMAST testing in 2005 [8] used...recalls the strategy used by SRTM, where a constellation of lights was installed at the tip of the boom and a modified star tracker was used to track tip

  5. Refinery water (intake and effluent) quality: Update of 1970s with 1990s toxicity testing

    International Nuclear Information System (INIS)

    Chapman, P.M.; Paine, M.D.; Moran, T.; Kierstead, T.

    1994-01-01

    The quality of two separate refinery intake waters and effluents was investigated: Petro-Canada (Oakville) and Novacor (Corunna Operations). This study comprised eight different test organized and 22 different toxicity end points, was built on and complemented pioneering 1970s work at the Petro-Canada refinery, and was designed to (a) determine any changes in effluent quality, (b) determine any previously unsuspected effluent toxicity, and (c) determine any potential for chronic toxicity in the effluent. Although Petro-Canada has steadily reduced contaminants in its effluent since the earlier study, toxicity has not changed and no new toxic effects were identified. Effect thresholds for the most sensitive animal species (Daphnia pulex) were 1 to 10% effluent in both studies. The Novacor effluent had lesser effects on biota than the Petro-Canada effluent. Intake waters demonstrated toxicity in some tests. Chronic effects on invertebrates and fish in receiving waters are predicted not to occur in the Novacor effluent is diluted 10- to 20-fold and the Petro-Canada effluent is diluted 50- to 100-fold

  6. Sensitivity of screening-level toxicity tests using soils from a former petroleum refinery

    International Nuclear Information System (INIS)

    Pauwels, S.; Bureau, J.; Roy, Y.; Allen, B.; Robidoux, P.Y.; Soucy, M.

    1995-01-01

    The authors tested five composite soil samples from a former refinery. The samples included a reference soil (Mineral Oil and Grease, MO and G < 40 ppm), thermally-treated soil, biotreated soil, and two untreated soils. They evaluated toxicity using the earthworm E. foetida, lettuce, cress, barley, Microtox, green algae, fathead minnow, and D. magna. The endpoints measured were lethality, seed germination, root elongation, growth, and bioluminescence. Toxicity, as measured by the number of positive responses, increased as follows: biotreated soil < untreated soil No. 1 < reference soil < thermally-treated soil and untreated soil No. 2. The biotreated soil generated only one positive response, whereas the thermally-treated soil and untreated soil No. 2 generated five positive responses. The most sensitive and discriminant terrestrial endpoint was lettuce root elongation which responded to untreated soil No. 1, thermally-treated soil, and reference soil. The least sensitive was barley seed germination for which no toxicity was detected. The most sensitive and discriminant aquatic endpoint was green algae growth which responded to untreated soil No. 1, thermally-treated soil, and reference soil. The least sensitive was D. magna for which no toxicity was detected. Overall, soil and aqueous extract toxicity was spotty and no consistent patterns emerged to differentiate the five soils. Biotreatment significantly reduced the effects of the contamination. Aqueous toxicity was measured in the reference soil, probably because of the presence of unknown dissolved compounds in the aqueous extract. Finally, clear differences in sensitivity existed among the test species

  7. Prediction of toxicity and comparison of alternatives using WebTEST (Web-services Toxicity Estimation Software Tool)(Bled Slovenia)

    Science.gov (United States)

    A Java-based web service is being developed within the US EPA’s Chemistry Dashboard to provide real time estimates of toxicity values and physical properties. WebTEST can generate toxicity predictions directly from a simple URL which includes the endpoint, QSAR method, and ...

  8. Inhalation method for delivery of nanoparticles to the Drosophila respiratory system for toxicity testing

    Energy Technology Data Exchange (ETDEWEB)

    Posgai, Ryan; Ahamed, Maqusood [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Hussain, Saber M. [Applied Biotechnology Branch, Human Effectiveness Directorate Air Force Research Laboratory/RHBP, Wright-Patterson Air Force Base, OH, 45433 (United States); Rowe, John J. [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States); Nielsen, Mark G., E-mail: Mark.Nielsen@notes.udayton.edu [Department of Biology, University of Dayton, Dayton, OH, 45469-2320 (United States)

    2009-12-20

    The growth of the nanotechnology industry and subsequent proliferation of nanoparticle types present the need to rapidly assess nanoparticle toxicity. We present a novel, simple and cost-effective nebulizer-based method to deliver nanoparticles to the Drosophila melanogaster respiratory system, for the purpose of toxicity testing. FluoSpheres (registered) , silver, and CdSe/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable of functioning with a wide range of nanoparticle types and sizes. Red fluorescent CdSe/ZnS nanoparticles were successfully delivered to the fly respiratory system, as visualized by fluorescent microscopy. Silver coated and uncoated nanoparticles were delivered in a toxicity test, and induced Hsp70 expression in flies, confirming the utility of this model in toxicity testing. This is the first method developed capable of such delivery, provides the advantage of the Drosophila health model, and can serve as a link between tissue culture and more expensive mammalian models in a tiered toxicity testing strategy.

  9. Inhalation method for delivery of nanoparticles to the Drosophila respiratory system for toxicity testing

    International Nuclear Information System (INIS)

    Posgai, Ryan; Ahamed, Maqusood; Hussain, Saber M.; Rowe, John J.; Nielsen, Mark G.

    2009-01-01

    The growth of the nanotechnology industry and subsequent proliferation of nanoparticle types present the need to rapidly assess nanoparticle toxicity. We present a novel, simple and cost-effective nebulizer-based method to deliver nanoparticles to the Drosophila melanogaster respiratory system, for the purpose of toxicity testing. FluoSpheres (registered) , silver, and CdSe/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable of functioning with a wide range of nanoparticle types and sizes. Red fluorescent CdSe/ZnS nanoparticles were successfully delivered to the fly respiratory system, as visualized by fluorescent microscopy. Silver coated and uncoated nanoparticles were delivered in a toxicity test, and induced Hsp70 expression in flies, confirming the utility of this model in toxicity testing. This is the first method developed capable of such delivery, provides the advantage of the Drosophila health model, and can serve as a link between tissue culture and more expensive mammalian models in a tiered toxicity testing strategy.

  10. Development and application of a sediment toxicity test using the benthic cladoceran Chydorus sphaericus

    International Nuclear Information System (INIS)

    Dekker, T.; Greve, G.D.; Ter Laak, T.L.; Boivin, M.E.; Veuger, B.; Gortzak, G.; Dumfries, S.; Luecker, S.M.G.; Kraak, M.H.S.; Admiraal, W.; Geest, H.G. van der

    2006-01-01

    This study reports on the development and application of a whole sediment toxicity test using a benthic cladoceran Chydorus sphaericus, as an alternative for the use of pelagic daphnids. A C. sphaericus laboratory culture was started and its performance under control conditions was optimised. The test was firstly validated by determining dose-response relationships for aqueous cadmium and copper and ammonia, showing a sensitivity of C. sphaericus (96 h LC 5 values of 594 μg Cd/L, 191 μg Cu/L and 46 mg ammonia/L at pH 8) similar to that of daphnids. Next, sediment was introduced into the test system and a series of contaminated sediments from polluted locations were tested. A significant negative correlation between survival and toxicant concentrations was observed. It is concluded that the test developed in the present study using the benthic cladoceran C. sphaericus is suitable for routine laboratory sediment toxicity testing. - A test was developed for assaying sediment toxicity using a commonly occurring small-bodied cladoceran

  11. Influences of the coating on silver nanoparticle toxicity in a chronic test with Daphnia magna

    DEFF Research Database (Denmark)

    Sakka, Y.; Mackevica, Aiga; Skjolding, Lars Michael

    2015-01-01

    coated AgNP in a chronic Daphnia test. One type of AgNP was coated with citrate (cAgNP), the other AgNP were generally uncoated (pAgNP; p= pure), but sterically stabilized by an organic dispersant. Particles with a similar shape and diameter were chosen. The focus of the study was to relate observed......Sources for differences in silver nanoparticle toxicity at standardized conditions can be numerous. They range from particle properties and their actual concentrations to differences in uptake or depuration by the test organisms. In the present study we compared the toxicity of two differently...... differences in toxicity to characteristics of the AgNP, like size or surface potential, or to their corresponding behaviour during the test, like dissolution or uptake. The characteristics and the behaviour of the AgNP were investigated for changes in stability and especially the release of silver ions...

  12. Photosynthesis tests as an alternative to growth tests for hazard assessment of toxicant

    DEFF Research Database (Denmark)

    Petersen, S.; Kusk, Kresten Ole

    2000-01-01

    Acute (3- and 6-h) toxic responses toward Cu, linear alkylbenzene sulfonate (LAS), and tributyltin (TBT) of lightsaturated and unsaturated photosynthesis were investigated for Rhodomonas salina and Skeletonema costatum obtained from exponentially growing batch cultures and from chemostat cultures...

  13. Quick, portable toxicity testing of marine or terrigenous fluids, sediments, or chemicals with bioluminescent organism

    International Nuclear Information System (INIS)

    Sabate, R.W.; Stiffey, A.V.; Dewailly, E.L.

    1995-01-01

    A hand-held, battery-operated instrument, which measures bioluminescence inhibition of the microscopic marine dinoflagellate Pyrocystis lunula, is capable of field-testing substances for toxicity. The organism is sensitive to ppb of strong toxicants. It tolerates some solvents in concentrations necessary for testing lipophylic samples. A test consumes only micrograms of sample. This method requires no adjustments for salinity, pH, color, or turbidity. It has been used successfully to test oil-well drilling fluids, brines produced with oil, waters and sediments from streams and lakes and petroleum-plant effluents containing contaminants such as benzene. The test is non-specific; however, if the substance is known, the end-point effects a direct measurement of its concentration. One-hour toxicity screening tests in the field produce results comparable to the standard four-hour laboratory test. Keeping the sample in the dark during incubation and testing, together with shortness of the overall procedure, eliminates anomalies from light-sensitive substances. Day-to-day variation, as well as among test replicates, is less than 10%. This quick method yields results comparable with a quick test that uses Photobacterium phosphoria, and with 96-hour tests that use Mysidopsis bahia, Artemia salina, Gonyaulax polyedra, Pimephales promelas, Ceriodaphnia dubia, and Cyprinodon variegatus

  14. Testing of CFC replacement fluids for arc-induced toxic by-products

    Energy Technology Data Exchange (ETDEWEB)

    Cravey, W.R.; Goerz, D.A.; Hawley-Fedder, R.A.

    1993-06-01

    The authors have developed a unique test-stand for quantifying the generation of perfluoroisobutylene (PFIB) in chlorofluorocarbon (CFC) replacement fluids when they are subjected to high electrical stress/breakdown environments. PFIB is an extremely toxic gas with a threshold limit value of 10 ppbv as set by the American Conference of Governmental Industrial Hygienists. They have tested several new fluids from various manufacturers for their potential to generate PFIB. Their goal is to determine breakdown characteristics and quantify toxic by-products of these replacement fluids to determine a safe, usable alternative for present CFC`s.

  15. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part III. Effluent toxicity tests

    Science.gov (United States)

    Dwyer, F.J.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Whites, D.W.; Augspurger, T.; Canfield, T.J.; Mount, D.R.; Mayer, F.L.

    2005-01-01

    Toxicity tests using standard effluent test procedures described by the U.S. Environmental Protection Agency were conducted with Ceriodaphnia dubia, fathead minnows (Pimephales promelas), and seven threatened and endangered (listed) fish species from four families: (1) Acipenseridae: shortnose sturgeon (Acipenser brevirostrum); (2) Catostomidae; razorback sucker (Xyrauchen texanus); (3) Cyprinidae: bonytail chub (Gila elegans), Cape Fear shiner (Notropis mekistocholas) Colorado pikeminnow (Ptychocheilus lucius), and spotfin chub (Cyprinella monacha); and (4) Poecillidae: Gila topminnow (Poeciliopsis occidentalis). We conducted 7-day survival and growth studies with embryo-larval fathead minnows and analogous exposures using the listed species. Survival and reproduction were also determined with C. dubia. Tests were conducted with carbaryl, ammonia-or a simulated effluent complex mixture of carbaryl, copper, 4-nonylphenol, pentachlorophenol and permethrin at equitoxic proportions. In addition, Cape Fear shiners and spotfin chub were tested using diazinon, copper, and chlorine. Toxicity tests were also conducted with field-collected effluents from domestic or industrial facilities. Bonytail chub and razorback suckers were tested with effluents collected in Arizona whereas effluent samples collected from North Carolina were tested with Cape Fear shiner, spotfin chub, and shortnose sturgeon. The fathead minnow 7-day effluent test was often a reliable estimator of toxic effects to the listed fishes. However, in 21 % of the tests, a listed species was more sensitive than fathead minnows. More sensitive species results varied by test so that usually no species was always more or less sensitive than fathead minnows. Only the Gila topminnow was consistently less sensitive than the fathead minnow. Listed fish species were protected 96% of the time when results for both fathead minnows and C. dubia were considered, thus reinforcing the value of standard whole

  16. Acute toxicity tests and meta-analysis identify gaps in tropical ecotoxicology for amphibians.

    Science.gov (United States)

    Ghose, Sonia L; Donnelly, Maureen A; Kerby, Jacob; Whitfield, Steven M

    2014-09-01

    Amphibian populations are declining worldwide, particularly in tropical regions where amphibian diversity is highest. Pollutants, including agricultural pesticides, have been identified as a potential contributor to decline, yet toxicological studies of tropical amphibians are very rare. The present study assesses toxic effects on amphibians of 10 commonly used commercial pesticides in tropical agriculture using 2 approaches. First, the authors conducted 8-d toxicity assays with formulations of each pesticide using individually reared red-eyed tree frog (Agalychnis callidryas) tadpoles. Second, they conducted a review of available data for the lethal concentration to kill 50% of test animals from the US Environmental Protection Agency's ECOTOX database to allow comparison with their findings. Lethal concentration estimates from the assays ranged over several orders of magnitude. The nematicides terbufos and ethoprophos and the fungicide chlorothalonil were very highly toxic, with evident effects within an order of magnitude of environmental concentrations. Acute toxicity assays and meta-analysis show that nematicides and fungicides are generally more toxic than herbicides yet receive far less research attention than less toxic herbicides. Given that the tropics have a high diversity of amphibians, the findings emphasize the need for research into the effects of commonly used pesticides in tropical countries and should help guide future ecotoxicological research in tropical regions. © 2014 SETAC.

  17. A high throughput passive dosing format for the Fish Embryo Acute Toxicity test

    DEFF Research Database (Denmark)

    Vergauwen, Lucia; Nørgaard Schmidt, Stine; Stinckens, Evelyn

    2015-01-01

    (lethal chemical activity) was 0.047. All values were within ranges expected for baseline toxicity. Impaired swim bladder inflation was the most pronounced morphological effect and swimming activity was reduced in all exposure concentrations. Further analysis showed that the effect on swimming activity...... dilution series. We report effect values for both mortality and sublethal morphological effects based on (1) measured exposure concentrations, (2) (lipid normalized) body residues and (3) chemical activity. The LC50 for 120 hpf was 310 μg/L, CBR50 (critical body residue) was 2.72 mmol/kg fresh wt and La50...... for obtaining mechanistic toxicity information, and (3) cause no toxicity, demonstrating its potential as an extension of the FET test when testing hydrophobic chemicals....

  18. PAH toxicity at aqueous solubility in the fish embryo test with Danio rerio using passive dosing

    DEFF Research Database (Denmark)

    Seiler, Thomas-Benjamin; Best, Nina; Fernqvist, Margit Møller

    2014-01-01

    to animal testing in (eco)toxicology. However, for hydrophobic organic chemicals it remains a technical challenge to ensure constant freely dissolved concentration at the maximum exposure level during such biotests. Passive dosing with PDMS silicone was thus applied to control the freely dissolved...... further data to support the close relationship between the chemical activity and the toxicity of hydrophobic organic compounds. Passive dosing from PDMS silicone enabled reliable toxicity testing of (highly) hydrophobic substances at aqueous solubility, providing a practical way to control toxicity...... exactly at the maximum exposure level. This approach is therefore expected to be useful as a cost-effective initial screening of hydrophobic chemicals for potential adverse effects to freshwater vertebrates....

  19. Development of a chronic sediment toxicity test for marine benthic amphipods

    International Nuclear Information System (INIS)

    DeWitt, T.H.; Redmond, M.S.; Sewall, J.E.; Swartz, R.C.

    1992-12-01

    The results of the research effort culminated in the development of a research method for assessing the chronic toxicity of contaminated marine and estuarine sediments using the benthic amphipod, Leptocheirus plumulosus. The first chapter describes the efforts at collecting, handling, and culturing four estuarine amphipods from Chesapeake Bay, including L. plumulosus. This chapter includes maps of the distribution and abundance of these amphipods within Chesapeake Bay and methodologies for establishing cultures of amphipods which could be readily adopted by other laboratories. The second chapter reports the development of acute and chronic sediment toxicity test methods for L. plumulosus, its sensitivity to non-contaminant environmental variables, cadmium, two polynuclear aromatic hydrocarbons, and contaminated sediment from Baltimore Harbor, MD. The third chapter reports the authors attempts to develop a chronic sediment toxicity test with Ampelisca abdita

  20. Argemone oil, an edible oil adulterant, induces systemic immunosuppression in Balb/c mice in an oral 28 days repeated dose toxicity study.

    Science.gov (United States)

    Mandal, Payal; Tewari, Prachi; Kumar, Sachin; Yadav, Sarika; Ayanur, Anjaneya; Chaturvedi, Rajnish K; Das, Mukul; Tripathi, Anurag

    2018-05-01

    Consumption of edible oils contaminated with Argemone oil (AO) leads to a clinical condition called "Epidemic dropsy". Earlier studies have reported that metabolism and oxidative stress primarily contributes to AO toxicity, however, the involvement of immune system has not been assessed so far. Therefore, the present study was undertaken to systematically assess the effect of AO exposure on the function of immune system in Balb/c mice. The repeated exposure of AO for 28 days caused prominent regression of spleen and thymus; severe inflammatory changes in spleen depicted by the loss of distinct follicles, increased megakaryocyte infiltration, and enhanced expression levels of inflammatory markers (iNOS & COX-2). At the functional level, AO exposure significantly abrogated the mixed lymphocyte reaction and mitogen-stimulated lymphoproliferative activity of T and B cells, which is reflective of profound lymphocyte dysfunction upon antigen exposure. In concordance with the loss in functional activity of lymphocytes in AO exposed animals, it was found the AO altered the relative percentage of CD3 + , CD4 + , and CD28  +  T cells. Further, there was a marked decrease in the relative distribution of cells with prominent MHC I and CD1d expression in AO exposed splenocytes. Moreover, reduced levels of immune stimulatory cytokines (TNF-α, IFN-γ, IL-2, IL-4, and IL-6), and increased levels of immunosuppressive cytokine IL-10 were detected in the serum of AO treated mice. Along with T and B cells, AO exposure also affected the phenotype and activation status of macrophages suggesting the inclination towards "alternative activation of macrophages". Altogether, these functional changes in the immune cells are contributing factors in AO induced immunosuppression. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier

    2016-01-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from...... nine countries participated in these ring-tests. Survival and reproduction were evaluated in L. stagnalis exposed to cadmium, tributyltin, prochloraz and trenbolone according to an OECD draft Test Guideline. In total, 49 datasets were analysed to assess the practicability of the proposed experimental...... protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary...

  2. IsTeen Court effective for repeat offenders? A test of the restorative justice approach.

    Science.gov (United States)

    Forgays, Deborah Kirby; DeMilio, Lisa

    2005-02-01

    Teen Courts are an effective judicial alternative for many youth offenders. The majority of youth courts deal solely with first-time offenders. However, repeat offenders are at a greater risk for future crime. Is Teen Court effective with more experienced offenders? In this study, the authors examine the outcomes of 26 Whatcom County Teen Court offenders with at least one prior conviction. The sentence completion rate was higher and the recidivism was lower for the Teen Court offenders when compared with a sample of first-time Court Diversion offenders. This objective evidence of program success is augmented by an offender's perspective on his or her court experience. These perspectives as well as the continued voluntary involvement with Teen Court are discussed in relation to empowerment theory.

  3. Effect of haemolysis and repeated freeze-thawing cycles on wild boar serum antibody testing by ELISA

    Directory of Open Access Journals (Sweden)

    Boadella Mariana

    2011-11-01

    Full Text Available Abstract Background Monitoring wildlife diseases is needed to identify changes in disease occurrence. Wildlife blood samples are valuable for this purpose but are often gathered haemolysed. To maximise information, sera often go through repeated analysis and freeze-thaw cycles. Herein, we used samples of clean and haemolysed Eurasian wild boar (Sus scrofa serum stored at -20°C and thawed up to five times to study the effects of both treatments on the outcome of a commercial ELISA test for the detection of antibodies against Suid Herpesvirus 1 (ADV. Results The estimated prevalence of antibodies against ADV was 50-53% for clean and haemolysed sera. Hence, haemolysis did not reduce the mean observed serum antibody prevalence. However, 10 samples changed their classification after repeated freeze-thawing. This included 3 (15% of the clean sera and 7 (41% of the haemolysed sera. Conclusions We recommend (1 establishing more restrictive cut-off values when testing wildlife sera, (2 recording serum quality prior to sample banking, (3 recording the number of freezing-thawing cycles and (4 store sera in various aliquots to reduce repeated usage. For instance, sera with more than 3 freeze-thaw cycles and a haemolysis of over 3 on a scale of 4 should better be discarded for serum antibody monitoring. Even clean (almost not haemolysed sera should not go through more than 5 freeze-thaw cycles.

  4. Effect of Methyl tert-Butyl Ether in Standard Tests for Mutagenicity and Environmental Toxicity

    Czech Academy of Sciences Publication Activity Database

    Vosáhlíková, M.; Cajthaml, Tomáš; Demnerová, K.; Pazlarová, Jarmila

    2006-01-01

    Roč. 21, č. 6 (2006), s. 599-605 ISSN 1520-4081 Institutional research plan: CEZ:AV0Z50200510 Keywords : toxicity * mtbe * ames test Subject RIV: EE - Microbiology, Virology Impact factor: 1.582, year: 2006

  5. Test of the acute lethal toxicity of pollutants to marine fish and invertebrates

    International Nuclear Information System (INIS)

    1989-01-01

    This reference method describes the measurement of the acute lethal toxicity of pollutants to marine animals (fish and invertebrates) by a static (non-continuous flow) method. Procedures are given for the determination of the toxicity curve (survival time-concentration relationship) and for the estimation of median lethal concentrations (LC50). The method is suitable for use with fish and macro-invertebrate species. It is not suitable for planktonic organisms nor for determining the toxicity of oil, oil dispersants or other petroleum products. Those methods are described in Reference Methods Nos. 44 and 45, respectively. The test animals are exposed, in groups of approximately ten, to each of several concentrations of the pollutant. The animals are observed, at intervals, for several days, the test solutions being renewed regularly. A record is maintained of the survival times of individual animals exposed to each concentration of pollutant. The medial survival time of each group of animals is determined from a graphical plot of the raw data after a log-probability transformation. Median survival times and their confidence limits are plotted against concentrations of test substance to give a toxicity curve. Additionally, the same experimental data can be used to estimate the median lethal concentration (LC50) of the test substance to the animals after different periods of exposure. 3 refs, 5 figs, 3 tabs

  6. Mode of Action Frameworks in Toxicity Testing and Chemical Risk Assessment

    NARCIS (Netherlands)

    Meek, B.

    2009-01-01

    Recently, legislative mandates worldwide are requiring systematic consideration of much larger numbers of chemicals. This necessitates more efficient and effective toxicity testing, as a basis to be more predictive in a risk assessment context. This in turn requires much more emphasis early in the

  7. Tox21: Putting a Lens on the Vision of Toxicity Testing in the 21st Century

    Science.gov (United States)

    In response to the release of the NRC report on "Toxicity Testing in the 21st Century, a Vision and Strategy" (NRC, 2007), two NIH institutes and EPA formed a collaboration (Tox21) to 1) identify mechanisms of chemically induced biological activity, 2) prioritize chemicals for mo...

  8. Development of a standard acute dietary toxicity test for the silkworm (Bombyx mori L.)

    NARCIS (Netherlands)

    Sun, X.; Valk, H.; Jiang, H.; Wang, X.; Yuan, S.; Zhang, Y.; Roessink, I.; Gao, X.

    2012-01-01

    Larvae of the silkworm (Bombyx mod L.) may be exposed to pesticide residues on the leaves of their food plant, the mulberry tree (Morus spp.), which can lead to adverse effects on silk production. A new acute dietary toxicity test method was evaluated as the basis for pesticide risk assessment. A

  9. Developmental toxicity of thyroid-active compounds in a zebrafish embryotoxicity test

    NARCIS (Netherlands)

    Jomaa, B.; Hermsen, S.A.B.; Kessels, M.Y.; Berg, van den J.H.J.; Peijenburg, A.C.M.; Aarts, J.M.M.J.G.; Piersma, A.H.; Rietjens, I.

    2014-01-01

    Zebrafish embryos were exposed to concentration ranges of selected thyroid-active model compounds in order to assess the applicability of zebrafish-based developmental scoring systems within an alternative testing strategy to detect the developmental toxicity of thyroid-active compounds. Model

  10. Animal alternatives for whole effluent toxicity testing: Perspectives from a global workshop (presentation)

    Science.gov (United States)

    Since the 1940s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that toxicit...

  11. Animal alternatives for whole effluent toxicity testing: Perspectives from a global workshop

    Science.gov (United States)

    Since the 1940’s, effluent toxicity testing has been utilized to varying degrees in many countries to assess potential ecological impacts and assist in determining necessary treatment options for environmental protection. However, it was only in the early 1980’s that ...

  12. 76 FR 38169 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2011-06-29

    ... (7405M), Office of Pollution Prevention and Toxics, Environmental Protection Agency, 1200 Pennsylvania... gold leaf, dyeing mixtures, antifreeze mixtures, extraction of resins and waxes, preservative for...: June 21, 2011. Maria J. Doa, Director, Chemical Control Division, Office of Pollution Prevention and...

  13. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier; Benstead, Rachel; Brettschneider, Denise; De Schamphelaere, Karel; Filipe Goncalves, Sandra; Green, John W; Holbech, Henrik; Hutchinson, Thomas H; Faber, Daniel; Laranjeiro, Filipe; Matthiessen, Peter; Norrgren, Leif; Oehlmann, Jörg; Reategui-Zirena, Evelyn; Seeland-Fremer, Anne; Teigeler, Matthias; Thome, Jean-Pierre; Tobor Kaplon, Marysia; Weltje, Lennart; Lagadic, Laurent

    2016-11-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from nine countries participated in these ring-tests. Survival and reproduction were evaluated in L. stagnalis exposed to cadmium, tributyltin, prochloraz and trenbolone according to an OECD draft Test Guideline. In total, 49 datasets were analysed to assess the practicability of the proposed experimental protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary statistical analysis, the optimal test duration was established and the most sensitive and cost-effective reproduction toxicity endpoint was identified, to be used as the core endpoint. This validation process and the resulting optimized protocol were used to consolidate the OECD Test Guideline for the evaluation of reproductive effects of chemicals in L. stagnalis. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Attentional and visual demands for sprint performance in non-fatigued and fatigued conditions: reliability of a repeated sprint test

    Directory of Open Access Journals (Sweden)

    Diercks Ron L

    2010-05-01

    Full Text Available Abstract Background Physical performance measures are widely used to assess physical function, providing information about physiological and biomechanical aspects of motor performance. However they do not provide insight into the attentional and visual demands for motor performance. A figure-of-eight sprint test was therefore developed to measure the attentional and visual demands for repeated-sprint performance. The aims of the study were: 1 to assess test-retest reliability of the figure-of-eight sprint test, and 2 to study the attentional and visual demands for sprint performance in a non-fatigued and fatigued condition. Methods Twenty-seven healthy athletes were included in the study. To determine test-retest reliability, a subgroup of 19 athletes performed the figure-of-eight sprint test twice. The figure-of-eight sprint test consisted of nine 30-second sprints. The sprint test consisted of three test parts: sprinting without any restriction, with an attention-demanding task, and with restricted vision. Increases in sprint times with the attention-demanding task or restricted vision are reflective of the attentional and visual demands for sprinting. Intraclass correlation coefficients (ICCs and mean difference between test and retest with 95% confidence limits (CL were used to assess test-retest reliability. Repeated-measures ANOVA were used for comparisons between the sprint times and fatigue measurements of the test parts in both a non-fatigued and fatigued condition. Results The figure-of-eight sprint test showed good test-retest reliability, with ICCs ranging from 0.75 to 0.94 (95% CL: 0.40-0.98. Zero lay within the 95% CL of the mean differences, indicating that no bias existed between sprint performance at test and retest. Sprint times during the test parts with attention-demanding task (P = 0.01 and restricted vision (P Conclusions High ICCs and the absence of systematic variation indicate good test-retest reliability of the figure

  15. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC{sub 50} values of other test models

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S., E-mail: bkhangarot@hotmail.com [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India); Das, Sangita [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2009-12-30

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC{sub 50}) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC{sub 50} values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r{sup 2}) for 17 physicochemical properties of metals or metal ions and EC{sub 50}s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK{sub sp}), softness parameter and some other physicochemical characteristics were significantly correlated with EC{sub 50}s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC{sub 50}s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  16. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC50 values of other test models

    International Nuclear Information System (INIS)

    Khangarot, B.S.; Das, Sangita

    2009-01-01

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC 50 ) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC 50 values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r 2 ) for 17 physicochemical properties of metals or metal ions and EC 50 s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK sp ), softness parameter and some other physicochemical characteristics were significantly correlated with EC 50 s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC 50 s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  17. Repeatability of a 3D multi-segment foot model during anterior and lateral step down tests.

    Science.gov (United States)

    Lucareli, Paulo Roberto Garcia; Contani, Luciane Beatriz Grohs; Lima, Bruna; Rabelo, Nayra Deise dos Anjos; Ferreira, Cintia Lopes; Lima, Fernanda Pulpio Silva; Correa, João Carlos Ferrari; Politti, Fabiano

    2016-01-01

    The aim of the present study was to analyse the reproducibility of the Oxford Foot Model (OFM) when used with healthy adults during two clinical tests, i.e., the Anterior Step Down Test (SDA) and the Lateral Step Down Test (SDL). Five healthy participants (one male and four females, 10 limbs in total) with a mean age of 22.2 (19-30) years were assessed in four sessions of tests conducted at intervals of one week. Two independent examiners performed two of the sessions of each of the tests. For each session (intra-day), nine repetitions of each clinical test (SDA and SDL) were performed. After an interval of three hours, the data were collected again. The tests were conducted again after an interval of one week using the same experimental conditions. The intra- and inter-session repeatabilities of the ranges of motion of the feet were determined according to the standard error of measurement (SEM) for each examiner and for the differences between the examiners. The repeatabilities of the results were high for both of the conducted tests. The SEM results were as follows: 0.47-1.94° for the intra-examiner assessment (SDA), 0.55-2.01° for the inter-examiner comparison (SDA), 0.44-2.43° for the intra-examiner assessment (SDL), and 0.54-1.89° for the inter-examiner comparison (SDL). The OFM model was shown to be reproducible in terms of assessing the range of motion of healthy adults during functional tests (SDA and SDL). Copyright © 2015 Elsevier B.V. All rights reserved.

  18. A portable cell-based impedance sensor for toxicity testing of drinking water.

    Science.gov (United States)

    Curtis, Theresa M; Widder, Mark W; Brennan, Linda M; Schwager, Steven J; van der Schalie, William H; Fey, Julien; Salazar, Noe

    2009-08-07

    A major limitation to using mammalian cell-based biosensors for field testing of drinking water samples is the difficulty of maintaining cell viability and sterility without an on-site cell culture facility. This paper describes a portable automated bench-top mammalian cell-based toxicity sensor that incorporates enclosed fluidic biochips containing endothelial cells monitored by Electric Cell-substrate Impedance Sensing (ECIS) technology. Long-term maintenance of cells on the biochips is made possible by using a compact, self-contained disposable media delivery system. The toxicity sensor monitors changes in impedance of cell monolayers on the biochips after the introduction of water samples. The fluidic biochip includes an ECIS electronic layer and a polycarbonate channel layer, which together reduce initial impedance disturbances seen in commercially available open well ECIS chips caused by the mechanics of pipetting while maintaining the ability of the cells to respond to toxicants. A curve discrimination program was developed that compares impedance values over time between the control and treatment channels on the fluidic biochip and determines if they are significantly different. Toxicant responses of bovine pulmonary artery endothelial cells grown on fluidic biochips are similar to cells on commercially-available open well chips, and these cells can be maintained in the toxicity sensor device for at least nine days using an automated media delivery system. Longer-term cell storage is possible; bovine lung microvessel endothelial cells survive for up to four months on the fluidic biochips and remain responsive to a model toxicant. This is the first demonstration of a portable bench top system capable of both supporting cell health over extended periods of time and obtaining impedance measurements from endothelial cell monolayers after toxicant exposure.

  19. Evaluation of the base/subgrade soil under repeated loading : phase II, in-box and ALF cyclic plate load tests.

    Science.gov (United States)

    2012-03-01

    This research study aims at evaluating the performance of base and subgrade soil in flexible pavements under repeated loading test conditions. For this purpose, an indoor cyclic plate load testing equipment was developed and used to conduct a series ...

  20. Isolation and toxicity test of Bacillus thuringiensis from Sekayu region soil, South Sumatra on Spodopteralitura

    Science.gov (United States)

    Afriani, S. R.; Pujiastuti, Y.; Irsan, C.; Damiri, N.; Nugraha, S.; Sembiring, E. R.

    2018-01-01

    This study aimed to obtain bacterial isolates B. thuringiensis potential as a biological control against pests Spodoptera litura. The research was conducted at the Laboratory of Pest and Disease Department, Agricultural Faculty of Sriwijaya University, Campus Inderalaya Ogan Ilir, South Sumatera, from March to June 2017. The study was conducted with survey method and laboratory trial. The results showed that of the 50 soil samples from three villages selected through morphological observation, reaction staining, KOH test, catalase test, producing 13 bacterial isolates. Screening of the 13th toxicity of the isolates suspected B. thuringiensis against S. litura larvae was investigated. Based on the toxicity screening test the following facts were obtained: five isolates ie KJ2M2, KJ3E1, KJ3JB1, KJ3D3 and KJ3D5 were lower toxicity than Dipel, two isolates ie KJ3K4 and KJ3D3 which had the same toxicity to Dipel. Five isolates the KJ3E3, KJ3BW5, KJ3JB5, KJ3D1 and LC2, LC3 known to have effectiveness until the seventh day reached 40%. There was one isolate that is KJ3BW5 which was more effective compared to Dipel as comparison.

  1. Experimental Analysis for Factors Affecting the Repeatability of Plastics Injection Molding Tests on the Self-developed Apparatus

    Directory of Open Access Journals (Sweden)

    Yugang Huang

    2013-06-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 To improve the repeatability of the injection molding test result, the affecting factors were investigated by means of experiments. Besides the traditional processing parameter, the factors of test conditions were also considered. In order to focus on the molding process rather than the molded part, the curve measurement of the melt pressure at the entrance to the nozzle was used as the output characteristic. Experiments for polypropylene (PP showed that the injected volume was the key processing parameter. Within the test conditions, the injection number is the most important factor. According to the analysis the operating procedure was improved effectively. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Doi: 10.12777/ijse.5.1.6-11 [How to cite this article: Huang, Y., Li, D., Liu, Y. (2013. Experimental Analysis for Factors Affecting the Repeatability of Plastics Injection Molding Tests on the Self-developed Apparatus. International Journal of Science and Engineering, 5(1,6-11. Doi: 10.12777/ijse.5.1.6-11]

  2. Testing Mean Differences among Groups: Multivariate and Repeated Measures Analysis with Minimal Assumptions.

    Science.gov (United States)

    Bathke, Arne C; Friedrich, Sarah; Pauly, Markus; Konietschke, Frank; Staffen, Wolfgang; Strobl, Nicolas; Höller, Yvonne

    2018-03-22

    To date, there is a lack of satisfactory inferential techniques for the analysis of multivariate data in factorial designs, when only minimal assumptions on the data can be made. Presently available methods are limited to very particular study designs or assume either multivariate normality or equal covariance matrices across groups, or they do not allow for an assessment of the interaction effects across within-subjects and between-subjects variables. We propose and methodologically validate a parametric bootstrap approach that does not suffer from any of the above limitations, and thus provides a rather general and comprehensive methodological route to inference for multivariate and repeated measures data. As an example application, we consider data from two different Alzheimer's disease (AD) examination modalities that may be used for precise and early diagnosis, namely, single-photon emission computed tomography (SPECT) and electroencephalogram (EEG). These data violate the assumptions of classical multivariate methods, and indeed classical methods would not have yielded the same conclusions with regards to some of the factors involved.

  3. Testing the Deployment Repeatability of a Precision Deployable Boom Prototype for the Proposed SWOT Karin Instrument

    Science.gov (United States)

    Agnes, Gregory S.; Waldman, Jeff; Hughes, Richard; Peterson, Lee D.

    2015-01-01

    NASA's proposed Surface Water Ocean Topography (SWOT) mission, scheduled to launch in 2020, would provide critical information about Earth's oceans, ocean circulation, fresh water storage, and river discharge. The mission concept calls for a dual-antenna Ka-band radar interferometer instrument, known as KaRIn, that would map the height of water globally along two 50 km wide swaths. The KaRIn antennas, which would be separated by 10 meters on either side of the spacecraft, would need to be precisely deployable in order to meet demanding pointing requirements. Consequently, an effort was undertaken to design build and prototype a precision deployable Mast for the KaRIn instrument. Each mast was 4.5-m long with a required dilitation stability of 2.5 microns over 3 minutes. It required a minimum first mode of 7 Hz. Deployment repeatability was less than +/- 7 arcsec in all three rotation directions. Overall mass could not exceed 41.5 Kg including any actuators and thermal blanketing. This set of requirements meant the boom had to be three times lighter and two orders of magnitude more precise than the existing state of the art for deployable booms.

  4. Leachates draining from controlled municipal solid waste landfill: Detailed geochemical characterization and toxicity tests.

    Science.gov (United States)

    Mavakala, Bienvenu K; Le Faucheur, Séverine; Mulaji, Crispin K; Laffite, Amandine; Devarajan, Naresh; Biey, Emmanuel M; Giuliani, Gregory; Otamonga, Jean-Paul; Kabatusuila, Prosper; Mpiana, Pius T; Poté, John

    2016-09-01

    Management of municipal solid wastes in many countries consists of waste disposal into landfill without treatment or selective collection of solid waste fractions including plastics, paper, glass, metals, electronic waste, and organic fraction leading to the unsolved problem of contamination of numerous ecosystems such as air, soil, surface, and ground water. Knowledge of leachate composition is critical in risk assessment of long-term impact of landfills on human health and the environment as well as for prevention of negative outcomes. The research presented in this paper investigates the seasonal variation of draining leachate composition and resulting toxicity as well as the contamination status of soil/sediment from lagoon basins receiving leachates from landfill in Mpasa, a suburb of Kinshasa in the Democratic Republic of the Congo. Samples were collected during the dry and rainy seasons and analyzed for pH, electrical conductivity, dissolved oxygen, soluble ions, toxic metals, and were then subjected to toxicity tests. Results highlight the significant seasonal difference in leachate physicochemical composition. Affected soil/sediment showed higher values for toxic metals than leachates, indicating the possibility of using lagoon system for the purification of landfill leachates, especially for organic matter and heavy metal sedimentation. However, the ecotoxicity tests demonstrated that leachates are still a significant source of toxicity for terrestrial and benthic organisms. Therefore, landfill leachates should not be discarded into the environment (soil or surface water) without prior treatment. Interest in the use of macrophytes in lagoon system is growing and toxic metal retention in lagoon basin receiving systems needs to be fully investigated in the future. This study presents useful tools for evaluating landfill leachate quality and risk in lagoon systems which can be applied to similar environmental compartments. Copyright © 2016 Elsevier Ltd. All

  5. Application of a novel integrated toxicity testing strategy incorporating "3R" principles of animal research to evaluate the safety of a new agrochemical sulfoxaflor.

    Science.gov (United States)

    Terry, Claire; Rasoulpour, Reza J; Saghir, Shakil; Marty, Sue; Gollapudi, B Bhaskar; Billington, Richard

    2014-05-01

    Plant protection products (PPPs) and the active substance(s) contained within them are rigorously and comprehensively tested prior to registration to ensure that human health is not impacted by their use. In recent years, there has been a widespread drive to have more relevant testing strategies (e.g., ILSI/HESI-ACSA and new EU Directives), which also take account of animal welfare, including the 3R (replacement, refinement, and reduction) principles. The toxicity potential of one such new active substance, sulfoxaflor, a sulfoximine insecticide (CAS #946578-00-3), was evaluated utilizing innovative testing strategies comprising: (1) an integrated testing scheme to optimize information obtained from as few animals as possible (i.e., 3R principles) through modifications of standard protocols, such as enhanced palatability study design, to include molecular endpoints, additional neurotoxicity and immunotoxicity parameters in a subchronic toxicity study, and combining multiple test guidelines into one study protocol; (2) generation of toxicokinetic data across dose levels, sexes, study durations, species, strains and life stages, without using satellite animals, which was a first for PPP development, and (3) addition of prospective mode of action (MoA) endpoints within repeat dose toxicity studies as well as proactive inclusion of specific MoA studies as an integral part of the development program. These novel approaches to generate key data early in the safety evaluation program facilitated informed decision-making on the need for additional studies and contributed to a more relevant human health risk assessment. This supplement also contains papers which describe in more detail the approach taken to establish the MoA and human relevance framework related to toxicities elicited by sulfoxaflor in the mammalian toxicology studies: developmental toxicity in rats mediated via the fetal muscle nicotinic acetylcholine receptor (nAChR) ( Ellis-Hutchings et al. 2014 ); liver

  6. Comparison of feeding strategies in acute toxicity tests of crude oil and commercial bioremediation agents

    International Nuclear Information System (INIS)

    Cavender, R.C.; Cherry, D.S.; Yeager, M.M.; Bidwell, J.R.

    1995-01-01

    Proposed modifications to the National Oil and Hazardous Substance Pollution Contingency Plan have prompted examinations of the methodology used in toxicity testing of the water soluble fraction (WSF) of oil, commercial bioremediation agents (CBA), and a combination of the two. The organisms currently used in acute (96 hr) testing of these agents are the inland silverside, Menidia beryllina, and an estuarine mysid, Mysidopsis bahia. The mysid is a carnivorous species that must be fed during a test in order to prevent predation within the test chambers. Currently proposed methodology for silverside testing also includes feeding. The high oxygen demand of CBAs and the WSF of oil causes dissolved oxygen to be a factor in toxicity. This effect can be intensified by the addition of brine shrimp (Artemia sp.) to the test chambers. The purpose of this study was to compare the toxicity of CBAs in combination with the WSF of oil to silversides with and without the addition of food. Tests were conducted using both 24-hour and 14-day spinning times for the CBA/WSF mixture. With the 24-hour spinning time, LC50 values from each day of the 4-day test were consistently lower in the Artemia fed test (47.8--22.6%) as compared to the unfed test (72.1--43.0%). A similar trend was seen in the 24 and 48 hour LC50's in the 14-day spinning time. Overall, low dissolved oxygen was found to be most relevant at the highest CBA/WSF concentrations where D.O. dropped below 2 mg/l in Artemia fed tests

  7. The effects of repeat testing, malingering, and traumatic brain injury on visuospatial memory span

    Directory of Open Access Journals (Sweden)

    David L Woods

    2016-01-01

    Full Text Available Spatial span tests such as the Corsi Block Test (CBT and the spatial span test of the Wechsler Memory Scale are widely used to assess deficits in spatial working memory. We conducted three experiments to evaluate the test-retest reliability and clinical sensitivity of a new computerized spatial span test (C-SST that incorporates psychophysical methods to improve the precision of spatial span measurement. In Experiment 1, we analyzed C-SST test-retest reliability in 49 participants who underwent three test sessions at weekly intervals. Intraclass correlation coefficients (ICC were higher for a psychophysically derived mean span (MnS metric (0.83 than for the maximal span and total correct metrics used in traditional spatial-span tests. Response times (ReTs also showed high ICCs (0.93 that correlated negatively with MnS scores and correlated positively with response-time latencies from other tests of processing speed. Learning effects were insignificant. Experiment 2 examined the performance of Experiment 1 participants when instructed to feign symptoms of traumatic brain injury: 57% showed abnormal MnS z-scores. A MnS z-score cutoff of 3.0 correctly classified 36% of simulated malingerers and 91% of the subgroup of 11 control participants with abnormal spans. Malingerers also made more substitution errors than control participants with abnormal spans (sensitivity = 43%, specificity = 91%. In addition, malingerers showed no evidence of ReT slowing, in contrast to significant abnormalities seen on other malingered tests of processing speed. As a result, differences between ReT z-scores and z-scores on other processing speed tests showed very high sensitivity and specificity in distinguishing malingering and control participants with either normal or abnormal spans. Experiment 3 examined C-SST performance in a group of patients with predominantly mild traumatic brain injury (TBI: neither MnS nor ReT z-scores showed significant group

  8. A case of natalizumab-associated progressive multifocal leukoencephalopathy with repeated negative CSF JCV testing.

    Science.gov (United States)

    Mazda, Monica E; Brosch, Jared R; Wiens, Andrea L; Bonnin, José M; Kamer, Aaron P; Mattson, David H; Snook, Riley J

    2013-05-01

    The development of progressive multifocal leukoencephalopathy (PML) in patients treated with natalizumab is a well-known potential risk. Diagnosis of PML can be confounded in patients with multiple sclerosis (MS) if new demyelinating lesions develop, and the sensitivity of existing diagnostic tests is less than ideal. In the case presented here, four samples of cerebrospinal fluid tested negative for John Cunningham virus (JCV) DNA by polymerase chain reaction, yet brain biopsy eventually proved positive by immunohistochemistry. A review of the limitations of existing clinical diagnostic tests is addressed, and we review the most recent literature on the proper management of natalizumab-treated MS patients.

  9. Toxicity testing and chemical analyses of recycled fibre-based paper for food contact

    DEFF Research Database (Denmark)

    Binderup, Mona-Lise; Pedersen, Gitte Alsing; Vinggaard, Anne

    2002-01-01

    of different qualities as food-contact materials and to Perform a preliminary evaluation of their suitability from a safety point of view, and, second, to evaluate the use of different in vitro toxicity tests for screening of paper and board. Paper produced from three different categories of recycled fibres (B...... of the paper products were extracted with either 99% ethanol or water. Potential migrants in the extracts were identified and semiquantified by GC-1R-MS or GC-HRMS. In parallel to the chemical analyses, a battery of four different in vitro toxicity tests with different endpoints were applied to the same...... was less cytotoxic than the extracts prepared from paper made from recycled fibres, and extracts prepared from C was the most cytotoxic. None of the extracts showed mutagenic activity No conclusion about the oestrogenic activity could be made, because all extracts were cytotoxic to the test organism (yeast...

  10. Ceriodaphnia and Chironomus in situ toxicity tests assessing the wastewater treatment efficacy of constructed wetlands

    International Nuclear Information System (INIS)

    Barjaktarovic, L.; Nix, P.; Gulley, J.

    1995-01-01

    In situ toxicity tests were designed for Ceriodaphnia dubia and Chironomus tentans as part of a larger study designed to assess the effectiveness of constructed wetlands for the treatment of wastewater produced by oil production at Suncor OSG. The artificial wetlands were 50m long by 3m wide, with three replicates of the control and the treatment. Each wetland had four sample sites equidistant along its length, creating a gradient of treatment from site A being the most toxic to site D being the least toxic. Each test was conducted twice during the summer of 1994. Both the Ceriodaphnia and Chironomus test cages were a flow through design to allow for maximal exposure to the water within the wetlands. Mortality and reproduction were used as endpoints for Ceriodaphnia, whereas mortality and growth were used as endpoints for the Chironomus test. Test durations were fifteen and ten days respectively. Chironomus had very high mortality along the entire wetlands whereas Ceriodaphnia survival and fecundity increased along the length of the treatment wetlands. Both organisms had low mortality and high growth/fecundity in the control wetlands

  11. Influence of potentially confounding factors on sea urchin porewater toxicity tests

    Science.gov (United States)

    Carr, R.S.; Biedenbach, J.M.; Nipper, M.

    2006-01-01

    The influence of potentially confounding factors has been identified as a concern for interpreting sea urchin porewater toxicity test data. The results from >40 sediment-quality assessment surveys using early-life stages of the sea urchin Arbacia punctulata were compiled and examined to determine acceptable ranges of natural variables such as pH, ammonia, and dissolved organic carbon on the fertilization and embryological development endpoints. In addition, laboratory experiments were also conducted with A. punctulata and compared with information from the literature. Pore water with pH as low as 6.9 is an unlikely contributor to toxicity for the fertilization and embryological development tests with A. punctulata. Other species of sea urchin have narrower pH tolerance ranges. Ammonia is rarely a contributing factor in pore water toxicity tests using the fertilization endpoint, but the embryological development endpoint may be influenced by ammonia concentrations commonly found in porewater samples. Therefore, ammonia needs to be considered when interpreting results for the embryological development test. Humic acid does not affect sea urchin fertilization at saturation concentrations, but it could have an effect on the embryological development endpoint at near-saturation concentrations. There was no correlation between sediment total organic carbon concentrations and porewater dissolved organic carbon concentrations. Because of the potential for many varying substances to activate parthenogenesis in sea urchin eggs, it is recommended that a no-sperm control be included with every fertilization test treatment. ?? 2006 Springer Science+Business Media, Inc.

  12. Evaluation of repeatability of Kansas test method KT-73, "density, absorption and voids in hardened concrete," boil test.

    Science.gov (United States)

    2015-06-01

    For years, the Kansas Department of Transportation (KDOT) and concrete producers in the state have used a : Rapid Chloride Test for concrete cylinders, AASHTO T277. This test has been thought of as an appropriate quality : control test to evaluate pe...

  13. Evaluation of repeatability of Kansas test method KT-73, "density, absorption and voids in hardened concrete," boil test : [technical summary].

    Science.gov (United States)

    2015-06-01

    For years, the Kansas Department of Transportation (KDOT) and concrete producers in : the state have used a Rapid Chloride Test for concrete cylinders, AASHTO T277. This : test has been thought of as an appropriate quality control test to evaluate pe...

  14. The Effects of Repeated Testing, Simulated Malingering, and Traumatic Brain Injury on Visual Choice Reaction Time

    Directory of Open Access Journals (Sweden)

    David L Woods

    2015-11-01

    Full Text Available Choice reaction time (CRT, the time required to discriminate and respond appropriately to different stimuli, is a basic measure of attention and processing speed. Here, we describe the reliability and clinical sensitivity of a new CRT test that presents lateralized visual stimuli and adaptively adjusts stimulus onset asynchronies (SOAs using a staircase procedure. Experiment 1 investigated the test-retest reliability in three test sessions at weekly intervals. Performance in the first test session was accurately predicted from age and computer-use regression functions obtained in a previously studied normative cohort. Central processing time (CentPT, the difference between the CRTs and simple reaction time latencies measured in a separate experiment, accounted for 55% of CRT latency and more than 50% of CRT latency variance. Performance improved significantly across the three test sessions. High intraclass correlation coefficients (ICCs were seen for CRTs (0.90, CentPTs (0.87, and an omnibus performance measure (0.81 that combined CRT and minimal SOA (mSOA z-scores. Experiment 2 investigated performance in the same participants when instructed to feign symptoms of traumatic brain injury (TBI: 87% produced abnormal omnibus z-scores. Simulated malingerers showed greater elevations in simple than choice reaction times, and hence reduced CentPTs. Latency-consistency z-scores, based on the difference between the CRTs obtained and those predicted from CentPT latencies, discriminated malingering participants from controls with high sensitivity and specificity. Experiment 3 investigated CRT test performance in military veterans who had suffered combat-related TBI and symptoms of post-traumatic stress disorder and revealed small but significant deficits in performance. The results indicate that the new CRT test shows high test-retest reliability, can assist in detecting participants performing with suboptimal effort, and is sensitive to the effects of

  15. The Hidden Burden of Outpatient Repeat PSA Testing in a Prospective Cohort

    LENUS (Irish Health Repository)

    Browne, E

    2017-05-01

    PSA testing is widespread throughout Europe for diagnostic purposes and follow up. We performed a prospective outpatient cohort study of 250 men (2013-2015) in two hospital sites. Included were those men being followed up by urology with PSA blood testing. First appointments and those men in whom non-PSA tests were ordered by urology were excluded. The median age was 67.2yrs (46-88). Eighty-one point two percent of samples had a combination of 21 different serology tests at an added cost of >€18,000. Abnormal serology resulted in 53 referrals. Twenty-six-six percentof correspondence referenced abnormal serology other than PSA. Follow up of non-PSA test results poses a challenge in an outpatient setting with failure to appropriately follow-up on abnormal results, increased costs, and medico-legal implications. There is currently no Irish legislature in place to safeguard hospital physicians. This study quantifies the levels of expenditure, resources and risk associated with ambulant PSA testing.

  16. Toxicity Testing of Restorative Dental Materials Using Brine Shrimp Larvae (Artemia salina

    Directory of Open Access Journals (Sweden)

    Manar M. Milhem

    2008-08-01

    Full Text Available This study investigated the effect of extracts of different composites, glass ionomer cement (GICs and compomers on the viability of brine shrimp larvae. Ethanolic extracts of four dental composites (Z-100; Solitaire 2; Filtek P60 and Synergy, a conventional GIC (Ketac-Fil, a resin-modified glass ionomer cement (Vitremer, two compomers (F2000; Dyract AP, and a flowable compomer (Dyract Flow were prepared from each material. Following evaporation of the ethanol, the extracts were resuspended in distilled water, which was then used to test the effects on the viability of brine shrimp larvae. For the composites, the extract of Synergy was the least toxic (88% viability followed by the extracts of Solitaire 2, Z100 and P60 (75%, 67.5% and 50% viability, respectively. One-way ANOVA revealed highly significant differences between the resin composite materials (p<0.001. Follow-up comparison between the composite groups by Tukey's pairwise multiple-comparison test (α =0.05 showed that the extract of Synergy was significantly less toxic than the extracts of all the other materials except that of Solitaire 2. The compomers showed 100% lethality, while the percentage of viable larvae for the extracts of Ketac-Fil, and Vitremer were 32.3%, and 37.0%, respectively. One-way ANOVA revealed highly significant differences between the groups of materials (p<0.001. Follow-up comparison between the groups by Tukey's test (α = 0.05 showed that the toxic effect of the extracts of the compomers were significantly greater than that of Ketac-Fil, and Vitremer. The differences in the toxic effects of Vitremer and Ketac-Fil were not statistically significant. In conclusion, the toxicity of composite materials varied according to their chemical composition. Compomers were the most lethal materials to brine shrimp larvae followed by GICs and then composites.

  17. History and sensitivity comparison of the Spirodela polyrhiza microbiotest and Lemna toxicity tests

    Directory of Open Access Journals (Sweden)

    Baudo R.

    2015-01-01

    Full Text Available The history of toxicity tests with duckweeds shows that these assays with free-floating aquatic angiosperms are gaining increasing attention in ecotoxicological research and applications. Standard tests have been published by national and international organizations, mainly with the test species Lemna minor and Lemna gibba. Besides the former two test species the great duckweed Spirodela polyrhiza is to date also regularly used in duckweed testing. Under unfavorable environmental conditions, the latter species produces dormant stages (turions and this has triggered the attention of two research groups from Belgium and Greece to jointly develop a “stock culture independent” microbiotest with S. polyrhiza. A 72 h new test has been worked out which besides its independence of stock culturing and maintenance of live stocks is very simple and practical to perform, and much less demanding in space and time than the conventional duckweed tests. Extensive International Interlaboratory Comparisons on the S. polyrhiza microbiotest showed its robustness and reliability and triggered the decision to propose this new assay to the ISO for endorsement and publication as a standard toxicity test for duckweeds. Sensitivity comparison of the 72 h S. polyrhiza microbiotest with the 7d L. minor assay for 22 compounds belonging to different groups of chemicals revealed that based on growth as the effect criterion both duckweed assays have a similar sensitivity. Taking into account its multiple advantages and assets, the S. polyrhiza microbiotest is a reliable and attractive alternative to the conventional duckweed tests.

  18. Optimizing the performance of Hyalella azteca in chronic toxicity tests: Results of feeding studies with various foods and feeding regimes

    Science.gov (United States)

    The freshwater amphipod Hyalella azteca is a common organism used for sediment toxicity testing in the United States and elsewhere. Standard methods for 10-d and 42-d toxicity tests with H. azteca were last revised and published by USEPA/ASTM in 2000. Under the methods in the man...

  19. A New, Sensitive Marine Microalgal Recombinant Biosensor Using Luminescence Monitoring for Toxicity Testing of Antifouling Biocides

    Science.gov (United States)

    Sanchez-Ferandin, Sophie; Leroy, Fanny; Bouget, François-Yves

    2013-01-01

    In this study, we propose the use of the marine green alga Ostreococcus tauri, the smallest free-living eukaryotic cell known to date, as a new luminescent biosensor for toxicity testing in the environment. Diuron and Irgarol 1051, two antifouling biocides commonly encountered in coastal waters, were chosen to test this new biosensor along with two degradation products of diuron. The effects of various concentrations of the antifoulants on four genetic constructs of O. tauri (based on genes involved in photosynthesis, cell cycle, and circadian clock) were compared using 96-well culture microplates and a luminometer to automatically measure luminescence over 3 days. This was compared to growth inhibition of O. tauri wild type under the same conditions. Luminescence appeared to be more sensitive than growth inhibition as an indicator of toxicity. Cyclin-dependent kinase (CDKA), a protein involved in the cell cycle, fused to luciferase (CDKA-Luc) was found to be the most sensitive of the biosensors, allowing an accurate determination of the 50% effective concentration (EC50) after only 2 days (diuron, 5.65 ± 0.44 μg/liter; Irgarol 1015, 0.76 ± 0.10 μg/liter). The effects of the antifoulants on the CDKA-Luc biosensor were then compared to growth inhibition in natural marine phytoplankton. The effective concentrations of diuron and Irgarol 1051 were found to be similar, indicating that this biosensor would be suitable as a reliable ecotoxicological test. The advantage of this biosensor over cell growth inhibition testing is that the process can be easily automated and could provide a high-throughput laboratory approach to perform short-term toxicity tests. The ability to genetically transform and culture recombinant O. tauri gives it huge potential for screening many other toxic compounds. PMID:23144143

  20. An empirical comparison of effective concentration estimators for evaluating aquatic toxicity test responses

    Energy Technology Data Exchange (ETDEWEB)

    Bailer, A.J.; Hughes, M.R.; Denton, D.L.; Oris, J.T.

    2000-01-01

    Aquatic toxicity tests are statistically evaluated by either hypothesis testing procedures to derive a no-observed-effect concentration or by inverting regression models to calculate the concentration associated with a specific reduction from the control response. These latter methods can be described as potency estimation methods. Standard US Environmental Protection Agency (USEPA) potency estimation methods are based on two different techniques. For continuous or count response data, a nominally nonparametric method that assumes monotonic decreasing responses and piecewise linear patterns between successive concentration groups is used. For quantal responses, a probit regression model with a linear dose term is fit. These techniques were compared with a recently developed parametric regression-based estimator, the relative inhibition estimator, RIp. This method is based on fitting generalized linear models, followed by estimation of the concentration associated with a particular decrement relative to control responses. These estimators, with levels of inhibition (p) of 25 and 50%, were applied to a series of chronic toxicity tests in a US EPA region 9 database of reference toxicity tests. Biological responses evaluated in these toxicity tests included the number of young produced in three broods by the water flea (Ceriodaphnia dubia) and germination success and tube length data from the giant kelp (Macrocystis pyrifera). The greatest discrepancy between the RIp and standard US EPA estimators was observed for C. dubia. The concentration-response pattern for this biological endpoint exhibited nonmonotonicity more frequently than for any of the other endpoint. Future work should consider optimal experimental designs to estimate these quantities, methods for constructing confidence intervals, and simulation studies to explore the behavior of these estimators under known conditions.

  1. Modified whole effluent toxicity test to assess and decouple wastewater effects from environmental gradients.

    Directory of Open Access Journals (Sweden)

    Sebastián Sauco

    Full Text Available Environmental gradients and wastewater discharges produce aggregated effects on marine populations, obscuring the detection of human impact. Classical assessment methods do not include environmental effects in toxicity tests designs, which could lead to incorrect conclusions. We proposed a modified Whole Effluent Toxicity test (mWET that includes environmental gradients in addition to effluent dilutions, together with the application of Generalized Linear Mixed Models (GLMM to assess and decouple those effects. We tested this approach, analyzing the lethal effects of wastewater on a marine sandy beach bivalve affected by an artificial canal freshwater discharge used for rice crops irrigation. To this end, we compared bivalve mortality between canal water dilutions (CWd and salinity controls (SC: without canal water. CWd were prepared by diluting the water effluent (sampled during the pesticide application period with artificial marine water. The salinity gradient was included in the design by achieving the same final salinities in both CWd and SC, allowing us to account for the effects of salinity by including this variable as a random factor in the GLMM. Our approach detected significantly higher mortalities in CWd, indicating potential toxic effects of the effluent discharge. mWET represents an improvement over the internationally standardized WET tests, since it considers environmental variability and uses appropriate statistical analyses.

  2. Rapid toxicity assessment using an in vivo enzyme test for Brachionus plicatilis (Rotifera).

    Science.gov (United States)

    Moffat, B D; Snell, T W

    1995-02-01

    A 1-hr in vivo enzyme inhibition assay based on esterase activity has good potential for marine toxicity assessment. A test was developed for the rotifer Brachionus plicatilis based on the nonfluorescent substrate fluorescein diacetate (FDA), which is metabolized by esterases to a fluorescent product. Enzyme inhibition, as determined by reduced fluorescence, can be scored visually or quantified using a fluorometer. Quantification of fluorescence permits the calculation of NOEC, LOEC, chronic value, and IC20. The 1-hr esterase inhibition test has sensitivity comparable to that of 24-hr rotifer acute tests for several compounds. The toxicity of six compounds was examined using the quantified assay. The resulting IC20s were within a factor of 3 of the 24-hour LC50s. IC20 values ranged from 0.017 mg/l for tributyltin to 3.1 mg/l for zinc, with an average coefficient of variation of 17.8%. Electrophoretic analysis of rotifer homogenates suggested that a single C esterase (acetylesterase) was responsible for FDA metabolism in B. plicatilis. Several other aquatic species are capable of metabolizing FDA, including Brachionus calyciflorus, Mysidopsis bahia, Menidia beryllina, Pimephales promelas, Ceriodaphnia dubia, Daphnia pulex, Artemia salina, and Ophryotrocha sp. The esterase inhibition test is an attractive tool for assessing aquatic toxicity because of its speed, simplicity, sensitivity, and applicability to a broad range of aquatic species.

  3. Relationship Between Skating Economy and Performance During a Repeated-Shift Test in Elite and Subelite Ice Hockey Players.

    Science.gov (United States)

    Lamoureux, Nicholas R; Tomkinson, Grant R; Peterson, Benjamin J; Fitzgerald, John S

    2018-04-01

    Lamoureux, NR, Tomkinson, GR, Peterson, BJ, and Fitzgerald, JS. Relationship between skating economy and performance during a repeated-shift test in elite and subelite ice hockey players. J Strength Cond Res 32(4): 1109-1113, 2018-The purpose of this study was to determine the importance of skating economy to fatigue during repeated high-intensity efforts of a simulated ice hockey shift. Forty-five collegiate and Junior A male ice hockey players (aged 18-24 years) performed a continuous graded exercise test using a skate treadmill. Breath-by-breath data for oxygen consumption (V[Combining Dot Above]O2) and respiratory exchange ratio were collected and used to derive energy expenditure (EE) averaged over the final 10 seconds of each stage. Economy was determined as the slope of the regression line relating V[Combining Dot Above]O2 and EE against skating speed separately. Participants also completed 8 bouts of maximal ice skating through a course designed to simulate typical shift, with timing gates determining first half, second half, and total fatigue decrement, calculated by a percent decrement score. Partial correlation was used to determine the association between economy measures and decrement during the repeated-shift test. Twenty-six participants met inclusion criteria and were included in data analysis. Skating economy measures (both relative V[Combining Dot Above]O2 and EE) were very likely moderate positive correlates of total fatigue decrement (r [95% confidence interval]: V[Combining Dot Above]O2, 0.46 [0.09, 0.72] and EE, 0.44, [0.06, 0.71]) but not with first or second gate decrement. Our results indicate that skating economy plays an important role in fatigue resistance over repeated on-ice sprints designed to simulate a typical shift. This supports the use of technical skating coaching and training techniques to enhance skating economy as a means of improving ice hockey performance.

  4. Robot-Assisted End-Effector-Based Stair Climbing for Cardiopulmonary Exercise Testing: Feasibility, Reliability, and Repeatability.

    Science.gov (United States)

    Stoller, Oliver; Schindelholz, Matthias; Hunt, Kenneth J

    2016-01-01

    Neurological impairments can limit the implementation of conventional cardiopulmonary exercise testing (CPET) and cardiovascular training strategies. A promising approach to provoke cardiovascular stress while facilitating task-specific exercise in people with disabilities is feedback-controlled robot-assisted end-effector-based stair climbing (RASC). The aim of this study was to evaluate the feasibility, reliability, and repeatability of augmented RASC-based CPET in able-bodied subjects, with a view towards future research and applications in neurologically impaired populations. Twenty able-bodied subjects performed a familiarisation session and 2 consecutive incremental CPETs using augmented RASC. Outcome measures focussed on standard cardiopulmonary performance parameters and on accuracy of work rate tracking (RMSEP-root mean square error). Criteria for feasibility were cardiopulmonary responsiveness and technical implementation. Relative and absolute test-retest reliability were assessed by intraclass correlation coefficients (ICC), standard error of the measurement (SEM), and minimal detectable change (MDC). Mean differences, limits of agreement, and coefficients of variation (CoV) were estimated to assess repeatability. All criteria for feasibility were achieved. Mean V'O2peak was 106±9% of predicted V'O2max and mean HRpeak was 99±3% of predicted HRmax. 95% of the subjects achieved at least 1 criterion for V'O2max, and the detection of the sub-maximal ventilatory thresholds was successful (ventilatory anaerobic threshold 100%, respiratory compensation point 90% of the subjects). Excellent reliability was found for peak cardiopulmonary outcome measures (ICC ≥ 0.890, SEM ≤ 0.60%, MDC ≤ 1.67%). Repeatability for the primary outcomes was good (CoV ≤ 0.12). RASC-based CPET with feedback-guided exercise intensity demonstrated comparable or higher peak cardiopulmonary performance variables relative to predicted values, achieved the criteria for V'O2max

  5. Robot-Assisted End-Effector-Based Stair Climbing for Cardiopulmonary Exercise Testing: Feasibility, Reliability, and Repeatability.

    Directory of Open Access Journals (Sweden)

    Oliver Stoller

    Full Text Available Neurological impairments can limit the implementation of conventional cardiopulmonary exercise testing (CPET and cardiovascular training strategies. A promising approach to provoke cardiovascular stress while facilitating task-specific exercise in people with disabilities is feedback-controlled robot-assisted end-effector-based stair climbing (RASC. The aim of this study was to evaluate the feasibility, reliability, and repeatability of augmented RASC-based CPET in able-bodied subjects, with a view towards future research and applications in neurologically impaired populations.Twenty able-bodied subjects performed a familiarisation session and 2 consecutive incremental CPETs using augmented RASC. Outcome measures focussed on standard cardiopulmonary performance parameters and on accuracy of work rate tracking (RMSEP-root mean square error. Criteria for feasibility were cardiopulmonary responsiveness and technical implementation. Relative and absolute test-retest reliability were assessed by intraclass correlation coefficients (ICC, standard error of the measurement (SEM, and minimal detectable change (MDC. Mean differences, limits of agreement, and coefficients of variation (CoV were estimated to assess repeatability.All criteria for feasibility were achieved. Mean V'O2peak was 106±9% of predicted V'O2max and mean HRpeak was 99±3% of predicted HRmax. 95% of the subjects achieved at least 1 criterion for V'O2max, and the detection of the sub-maximal ventilatory thresholds was successful (ventilatory anaerobic threshold 100%, respiratory compensation point 90% of the subjects. Excellent reliability was found for peak cardiopulmonary outcome measures (ICC ≥ 0.890, SEM ≤ 0.60%, MDC ≤ 1.67%. Repeatability for the primary outcomes was good (CoV ≤ 0.12.RASC-based CPET with feedback-guided exercise intensity demonstrated comparable or higher peak cardiopulmonary performance variables relative to predicted values, achieved the criteria for V'O2

  6. Handbook of acute toxicity of chemicals to fish and aquatic invertebrates : summaries of toxicity tests conducted at Columbia National Fisheries Research Laboratory, 1965-78

    Science.gov (United States)

    Johnson, W. Waynon; Finley, Mack T.

    1980-01-01

    Acute toxicity is a major subject of research at Columbia National Fisheries Research Laboratory for evaluating the impact of toxic chemicals on fishery resources. The Laboratory has played a leading role in developing research technology for toxicity testing and data interpretation. In 1965-78, more than 400 chemicals were tested against a variety of invertebrates and fish species representative of both cold- and warm-water climates.The use of acute toxicity tests for assessing the potential hazard of chemical contaminants to aquatic organisms is well documented (Boyd 1957; Henderson et al. 1960; Sanders and Cope 1966; Macek and McAllister 1970). Static acute toxicity tests provide rapid and (within limits) reproducible concentration-response curves for estimating toxic effects of chemicals on aquatic organisms. These tests provide a database for determining relative toxicity of a large number of chemicals to a variety of species and for estimating acute effects of chemical spills on natural aquatic systems; they also assist in determining priority and design of additional toxicity studies.Acute toxicity tests usually provide estimates of the exposure concentration causing 50% mortality (LC50) to test organisms during a specified period of time. For certain invertebrates, the effective concentration is based on immobilization, or some other identifiable endpoint, rather than on lethality. The application of the LC50 has gained acceptance among toxicologists and is generally the most highly rated test for assessing potential adverse effects of chemical contaminants to aquatic life (Brungs and Mount 1978; American Institute for Biological Sciences 1978a).The literature contains numerous papers dealing with the acute toxicity of chemicals to freshwater organisms. However, there is a tremendous need for a concise compendium of toxicity data covering a large variety of chemicals and test species. This Handbook is a compilation of a large volume of acute toxicity data

  7. Test Results for a Non-toxic, Dual Thrust Reaction Control Engine

    Science.gov (United States)

    Robinson, Philip J.; Veith, Eric M.; Turpin, Alicia A.

    2005-01-01

    A non-toxic, dual thrust reaction control engine (RCE) was successfully tested over a broad range of operating conditions at the Aerojet Sacramento facility. The RCE utilized LOX/Ethanol propellants; and was tested in steady state and pulsing modes at 25-lbf thrust (vernier) and at 870-lbf thrust (primary). Steady state vernier tests vaned chamber pressure (Pc) from 0.78 to 5.96 psia, and mixture ratio (MR) from 0.73 to 1.82, while primary steady state tests vaned Pc from 103 to 179 psia and MR from 1.33 to 1.76. Pulsing tests explored EPW from 0.080 to 10 seconds and DC from 5 to 50 percent at both thrust levels. Vernier testing accumulated a total of 6,670 seconds of firing time, and 7,215 pulses, and primary testing accumulated a total of 2,060 seconds of firing time and 3,646 pulses.

  8. 76 FR 65385 - Testing of Certain High Production Volume Chemicals; Third Group of Chemicals

    Science.gov (United States)

    2011-10-21

    ... Mutations: Bacterial Reverse Mutation Test (in vitro): 40 CFR 799.9510. b. Chromosomal Damage: In Vitro... alternate test. 6. Mammalian Toxicity--Repeated Dose/Reproduction/Developmental--a. Combined Repeated Dose Toxicity Study with the Reproduction/ Developmental Toxicity Screening Test: 40 CFR 799.9365. b...

  9. Full-thickness human skin explants for testing the toxicity of topically applied chemicals

    International Nuclear Information System (INIS)

    Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr.

    1990-01-01

    This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36 degrees C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components

  10. Full-thickness human skin explants for testing the toxicity of topically applied chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, M.; Rikimaru, T.; Yano, T.; Moore, K.G.; Pula, P.J.; Schofield, B.H.; Dannenberg, A.M. Jr. (Johns Hopkins Univ., Baltimore, MD (USA))

    1990-09-01

    This report describes a model organ-culture system for testing the toxicity of chemical substances that are topically applied to human skin. In this system, the viable keratinocytes in the full-thickness skin explants are protected by the same keratinized layer as skin remaining on the donor, and toxicity can be assessed microscopically and/or biochemically. The human skin specimens were discards from a variety of surgical procedures. They were cut into full-thickness 1.0-cm2 explants, and briefly exposed to the military vesicant sulfur mustard (SM), which was used as a model toxicant. The explants were then organ cultured in small Petri dishes for 24 h at 36 degrees C. In the 0.03-1.0% dosage range, a straight-line dose-response relationship occurred between the concentration of SM applied and the number of paranuclear vacuoles seen histologically in the epidermis. Within the same SM dosage range, there was also a proportional decrease in 14C-leucine incorporation by the explants. Thus, the number of paranuclear vacuoles reflected decreases in protein synthesis by the injured epidermal cells. The epidermis of full-thickness untreated (control) human skin explants usually remained viable for 7 d when stored at 4 degrees C in culture medium. During storage, a relatively small number of paranuclear vacuoles developed within the epidermis, but the explants were still quite satisfactory for testing SM toxicity. Incubation (for 4 or 24 h at 36{degrees}C) of such control skin explants reduced (often by 50%) the small number of paranuclear vacuoles produced during 4-7 d of storage. This reduction was probably caused by autolysis of many of the vacuolated cells. Two types of paranuclear vacuoles could be identified by both light and electron microscopy: a storage type and a toxicant type. The storage type seemed to be caused by autolysis of cell components.

  11. An assessment of whole effluent toxicity testing as a means of regulating waters produced by the oil and gas industry

    International Nuclear Information System (INIS)

    Hill, S.L.; Bergman, H.L.

    1993-01-01

    Approximately 500 million barrels of produced water are discharged to Wyoming's surface waters by the oil and gas industry. This discharges are of two types: direct and indirect. The direct discharges have been issued NPDES permits requiring whole effluent toxicity testing. Toxicity testing requirements have not been incorporated into permits written for indirect discharges because of the applicability of toxicity testing for regulating these waters has not been determined. Preliminary testing has shown that most produced waters are toxic at the point of discharge because of high concentrations of hydrogen sulfide, but that the toxicity of an indirect discharge is often lost before it reaches a receiving stream. Thus, whole effluent toxicity testing of an indirect discharge may be overly stringent, resulting in treatment or reinjection of the water or closure of the well. Any of these options would have severe economic consequences for oil producers and the state's agricultural industry. The purpose of this study was to determine whether whole effluent toxicity testing actually predicts the in-stream effects of indirect discharges on water quality and benthic invertebrate populations. The authors will report the results of short-term ambient toxicity tests and in-stream bioassessments performed upstream and downstream of six indirect discharges located in four drainages in Wyoming

  12. Mercury Induced Biochemical Alterations As Oxidative Stress In Mugil Cephalus In Short Term Toxicity Test

    OpenAIRE

    J.S.I Rajkumar; Samuel Tennyson

    2013-01-01

    Mugil cephalus juveniles of size 2.5 ±0.6cm were exposed to mercury in short term chronic toxicity test through static renewal bioassay to detect the possible biochemical agent as biomarkers in aquatic pollution and in estuarine contamination as specific. Lipid peroxidation levels, glutathione S -transferase, catalase, reduced glutathione and acetylcholinesterase were studied as biochemical parameters. Increased thio-barbituric acid reactive substances levels were observed under exposur...

  13. Evaluation of the toxic effect of endocrine disruptor Bisphenol A (BPA) in the acute and chronic toxicity tests with Pomacea lineata gastropod.

    Science.gov (United States)

    de Andrade, André Lucas Correa; Soares, Priscila Rafaela Leão; da Silva, Stephannie Caroline Barros Lucas; da Silva, Marília Cordeiro Galvão; Santos, Thamiris Pinheiro; Cadena, Marilia Ribeiro Sales; Soares, Pierre Castro; Cadena, Pabyton Gonçalves

    2017-07-01

    Bisphenol A (BPA) is a plasticizer and a risk when it interacts with organisms, and can cause changes in the development and reproduction of them. This study aimed to evaluate the effects of BPA, by acute and chronic toxicity tests with neonates and adults of Pomacea lineata. Adults and neonates were divided into groups exposed to BPA (1-20mg/L), or 17β-estradiol (1mg/L) and control in the acute and chronic toxicity tests. Behavior, heart rate, reproduction and hemolymph biochemical analysis were measured. In the acute toxicity test, the 96-h LC 50 with adults was 11.09 and with neonates was 3.14mg/L. In this test, it was observed lethargic behavior and an increase of 77.6% of aspartate aminotransferase in the adults' hemolymph (ptest, it was observed behaviors associated with reproduction, as Copulate, in the groups exposed to BPA. The results that were found in this study proved that BPA is a potentially toxic agent to Pomacea lineata according to biological parameters evaluated. These data contribute to the understanding of BPA toxic effects' in the aquatic invertebrates. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Monitoring the effectiveness of remediation techniques using sediment toxicity tests with the amphipod Eohaustorius estuarius

    International Nuclear Information System (INIS)

    Doe, K.G.; Jackman, P.M.; Lee, K.

    2002-01-01

    The results of a controlled oil release experiment of weathered crude oil was presented. The released oil was applied to a tidal saltwater marsh at Conrod's Beach, Nova Scotia, Canada. The study included 3 replicate blocks which included 2 unoiled treatments and 4 oiled treatments for each block. One unoiled site had no treatment, the second unoiled site had nutrient addition to examine the effect of nutrients. The oiled treatments included natural attenuation, nutrient addition, nutrient addition with plants, and nutrient addition with a garden aerator to introduce oxygen. A standard lab procedure was used to analyze the sediments to determine the effectiveness of the technique as well as the toxic effects on the survival of the amphipod Eohaustorius estuarius. Test results indicated that the unoiled sites were non-toxic, with a slight decrease in survival in the treatment with nutrient addition. All the oiled sites were very toxic at first, but toxicity decreased gradually with time. Treatment with nutrient addition with a garden aerator proved to be the most complete and fastest detoxification method. 8 refs., 4 tabs., 2 figs

  15. Sirc-cvs cytotoxicity test: an alternative for predicting rodent acute systemic toxicity.

    Science.gov (United States)

    Kitagaki, Masato; Wakuri, Shinobu; Hirota, Morihiko; Tanaka, Noriho; Itagaki, Hiroshi

    2006-10-01

    An in vitro crystal violet staining method using the rabbit cornea-derived cell line (SIRC-CVS) has been developed as an alternative to predict acute systemic toxicity in rodents. Seventy-nine chemicals, the in vitro cytotoxicity of which was already reported by the Multicenter Evaluation of In vitro Toxicity (MEIC) and ICCVAM/ECVAM, were selected as test compounds. The cells were incubated with the chemicals for 72 hrs and the IC(50) and IC(35) values (microg/mL) were obtained. The results were compared to the in vivo (rat or mouse) "most toxic" oral, intraperitoneal, subcutaneous and intravenous LD(50) values (mg/kg) taken from the RTECS database for each of the chemicals by using Pearson's correlation statistics. The following parameters were calculated: accuracy, sensitivity, specificity, prevalence, positive predictability, and negative predictability. Good linear correlations (Pearson's coefficient; r>0.6) were observed between either the IC(50) or the IC(35) values and all the LD(50) values. Among them, a statistically significant high correlation (r=0.8102, p50) values and the oral LD(50) values. By using the cut-off concentrations of 2,000 mg/kg (LD(50)) and 4,225 microg/mL (IC(50)), no false negatives were observed, and the accuracy was 84.8%. From this, it is concluded that this method could be used to predict the acute systemic toxicity potential of chemicals in rodents.

  16. Statistical methods for conducting agreement (comparison of clinical tests) and precision (repeatability or reproducibility) studies in optometry and ophthalmology.

    Science.gov (United States)

    McAlinden, Colm; Khadka, Jyoti; Pesudovs, Konrad

    2011-07-01

    The ever-expanding choice of ocular metrology and imaging equipment has driven research into the validity of their measurements. Consequently, studies of the agreement between two instruments or clinical tests have proliferated in the ophthalmic literature. It is important that researchers apply the appropriate statistical tests in agreement studies. Correlation coefficients are hazardous and should be avoided. The 'limits of agreement' method originally proposed by Altman and Bland in 1983 is the statistical procedure of choice. Its step-by-step use and practical considerations in relation to optometry and ophthalmology are detailed in addition to sample size considerations and statistical approaches to precision (repeatability or reproducibility) estimates. Ophthalmic & Physiological Optics © 2011 The College of Optometrists.

  17. Modeling the rate of HIV testing from repeated binary data amidst potential never-testers.

    Science.gov (United States)

    Rice, John D; Johnson, Brent A; Strawderman, Robert L

    2018-01-04

    Many longitudinal studies with a binary outcome measure involve a fraction of subjects with a homogeneous response profile. In our motivating data set, a study on the rate of human immunodeficiency virus (HIV) self-testing in a population of men who have sex with men (MSM), a substantial proportion of the subjects did not self-test during the follow-up study. The observed data in this context consist of a binary sequence for each subject indicating whether or not that subject experienced any events between consecutive observation time points, so subjects who never self-tested were observed to have a response vector consisting entirely of zeros. Conventional longitudinal analysis is not equipped to handle questions regarding the rate of events (as opposed to the odds, as in the classical logistic regression model). With the exception of discrete mixture models, such methods are also not equipped to handle settings in which there may exist a group of subjects for whom no events will ever occur, i.e. a so-called "never-responder" group. In this article, we model the observed data assuming that events occur according to some unobserved continuous-time stochastic process. In particular, we consider the underlying subject-specific processes to be Poisson conditional on some unobserved frailty, leading to a natural focus on modeling event rates. Specifically, we propose to use the power variance function (PVF) family of frailty distributions, which contains both the gamma and inverse Gaussian distributions as special cases and allows for the existence of a class of subjects having zero frailty. We generalize a computational algorithm developed for a log-gamma random intercept model (Conaway, 1990. A random effects model for binary data. Biometrics46, 317-328) to compute the exact marginal likelihood, which is then maximized to obtain estimates of model parameters. We conduct simulation studies, exploring the performance of the proposed method in comparison with

  18. Toxicity minimization of pipelines hydrostatic tests fluids, stage I: laboratory essays

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, Jorge A.S.; Penna, Monica de O.; Portela, Daniele B.; Christino, Fernando P.; Silva, Joao L.B. da; Geraldo, Lucia M.L. [Petroleo do Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Mota, Vanessa V.C. [Fundacao Gorceix, Ouro Preto, MG (Brazil); Cravo Junior, Walter [Pontificia Univ. Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil)

    2009-07-01

    This paper presents the results of the laboratory essays stage of the project for toxicity minimization of pipelines hydrostatic tests fluids. The hydrostatic-hibernation fluid composition most used by PETROBRAS in offshore operations is seawater added with sodium bis sulfite, fluorescein, alquildimetilbenzilamonium chloride, and tetrakis-hydroxymethyl-phosphonium sulfate (THPS). In order to reduce the toxicity of the fluid used in hydrostatic tests, the use of lesser concentrations of THPS was attempted with UV radiation application as a disinfection technique prior to the adding of the fluid's components. The compositions were evaluated in different conditions of temperature use of UV radiation or not and oxygen scavenger adding (presence and absence). The fluids were kept hibernating for 120 days. All the parameters tested after hibernation were compared to fresh from preparation samples (zero time samples). The fluid's characteristics were evaluated by microbiological control and toxicity as well as the THPS residual. Results showed that the UV treatment was more effective in the absence of oxygen scavenger. The temperature acts as a microbial growth control agent, as expected. To large scale operations, a water quality monitoring must be performed previously to any field operations, in order to determinate the best treatment to be used in each case. (author)

  19. Testing Accuracy and Repeatability of UAV Blocks Oriented with GNSS-Supported Aerial Triangulation

    Directory of Open Access Journals (Sweden)

    Francesco Benassi

    2017-02-01

    Full Text Available UAV Photogrammetry today already enjoys a largely automated and efficient data processing pipeline. However, the goal of dispensing with Ground Control Points looks closer, as dual-frequency GNSS receivers are put on board. This paper reports on the accuracy in object space obtained by GNSS-supported orientation of four photogrammetric blocks, acquired by a senseFly eBee RTK and all flown according to the same flight plan at 80 m above ground over a test field. Differential corrections were sent to the eBee from a nearby ground station. Block orientation has been performed with three software packages: PhotoScan, Pix4D and MicMac. The influence on the checkpoint errors of the precision given to the projection centers has been studied: in most cases, values in Z are critical. Without GCP, the RTK solution consistently achieves a RMSE of about 2–3 cm on the horizontal coordinates of checkpoints. In elevation, the RMSE varies from flight to flight, from 2 to 10 cm. Using at least one GCP, with all packages and all test flights, the geocoding accuracy of GNSS-supported orientation is almost as good as that of a traditional GCP orientation in XY and only slightly worse in Z.

  20. Chronic exercise prevents repeated restraint stress-provoked enhancement of immobility in forced swimming test in ovariectomized mice.

    Science.gov (United States)

    Han, Tae-Kyung; Lee, Jang-Kyu; Leem, Yea-Hyun

    2015-06-01

    We assessed whether chronic treadmill exercise attenuated the depressive phenotype induced by restraint stress in ovariectomized mice (OVX). Immobility of OVX in the forced swimming test was comparable to that of sham mice (CON) regardless of the postoperative time. Immobility was also no difference between restrained mice (exposure to periodic restraint for 21 days; RST) and control mice (CON) on post-exposure 2nd and 9th day, but not 15th day. In contrast, the immobility of ovariectomized mice with repeated stress (OVX + RST) was profoundly enhanced compared to ovariectomized mice-alone (OVX), and this effect was reversed by chronic exercise (19 m/min, 60 min/day, 5 days/week for 8 weeks; OVX + RST + Ex) or fluoxetine administration (20 mg/kg, OVX + RST + Flu). In parallel with behavioral data, the immunoreactivity of Ki-67 and doublecortin (DCX) in OVX was significantly decreased by repeated stress. However, the reduced numbers of Ki-67- and DCX-positive cells in OVX + RST were restored in response to chronic exercise (OVX + RST + Ex) and fluoxetine (OVX + RST + Flu). In addition, the expression pattern of cAMP response element-binding protein (CREB) and calcium-calmodulin-dependent kinase IV (CaMKIV) was similar to that of the hippocampal proliferation and neurogenesis markers (Ki-67 and DCX, respectively). These results suggest that menopausal depression may be induced by an interaction between repeated stress and low hormone levels, rather than a deficit in ovarian secretion alone, which can be improved by chronic exercise.

  1. 76 FR 38170 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

    Science.gov (United States)

    2011-06-29

    ... must be visible at all times in the building and returned upon departure. II. Test Data Submissions EPA... required by the applicable standards for the development of test data. 3. Describe the nature of the test.... See note. Chinese Hamster Ovary (CHO) Cells. Activated Sludge Die-away 0275.1. Copyrighted...

  2. Significance of repeated exercise testing with thallium-201 scanning in asymptomatic diabetic males

    International Nuclear Information System (INIS)

    Rubler, S.; Fisher, V.J.

    1985-01-01

    This study was conducted with asymptomatic middle-aged male subjects with diabetes mellitus to detect latent cardiac disease using noninvasive techniques. One group of 38 diabetic males (mean age 50.5 +/- 10.2 years) and a group of 15 normal males (mean age 46.9 +/- 10.0 years) participated in the initial trial; 13 diabetic patients and 7 control subjects were restudied 1-2 years later. Maximal treadmill exercise with a Bruce protocol and myocardial scintigraphy with thallium-201(201Tl) were used. Diabetic subjects on initial examination and retesting achieved a lower maximal heart rate and duration of exercise than control subjects. Abnormal electrocardiographic changes, thallium defects, or both were observed in 23/38 diabetic males (60.5%) on the first study and only one 65-year-old control subject had such findings. On retesting, the control subjects had no abnormalities while 76.9% of diabetic subjects had either 201Tl defects or ECG changes. We conclude that despite the fact that none of diabetic males had any clinical evidence or symptoms of heart disease, this high-risk group demonstrated abnormalities on exercise testing that merit careful subsequent evaluation and followup and could be an effective method of detecting early cardiac disease

  3. Seed germination test for toxicity evaluation of compost: Its roles, problems and prospects.

    Science.gov (United States)

    Luo, Yuan; Liang, Jie; Zeng, Guangming; Chen, Ming; Mo, Dan; Li, Guoxue; Zhang, Difang

    2018-01-01

    Compost is commonly used for the growth of plants and the remediation of environmental pollution. It is important to evaluate the quality of compost and seed germination test is a powerful tool to examine the toxicity of compost, which is the most important aspect of the quality. Now the test is widely adopted, but the main problem is that the test results vary with different methods and seed species, which limits the development and application of it. The standardization of methods and the modelization of seeds can contribute to solving the problem. Additionally, according to the probabilistic theory of seed germination, the error caused by the analysis and judgment methods of the test results can be reduced. Here, we reviewed the roles, problems and prospects of the seed germination test in the studies of compost. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Ecotoxicity of engineered nanoparticles to aquatic invertebrates: a brief review and recommendations for future toxicity testing

    DEFF Research Database (Denmark)

    Baun, Anders; Hartmann, Nanna Isabella Bloch; Grieger, Khara Deanne

    2008-01-01

    Based on a literature review and an overview of toxic effects of engineered nanoparticles in aquatic invertebrates, this paper proposes a number of recommendations for the developing field of nanoecotoxicology by highlighting the importance of invertebrates as sensitive and relevant test organisms...... through standardized short-term (lethality) tests with invertebrates as a basis for investigating behaviour and bioavailability of engineered nanoparticles in the aquatic environment. Based on this literature review, we further recommend that research is directed towards invertebrate tests employing long....... Results show that there is a pronounced lack of data in this field (less than 20 peer-reviewed papers are published so far), and the most frequently tested engineered nanoparticles in invertebrate tests are C-60, carbon nanotubes, and titanium dioxide. In addition, the majority of the studies have used...

  5. Creating multithemed ecological regions for macroscale ecology: Testing a flexible, repeatable, and accessible clustering method

    Science.gov (United States)

    Cheruvelil, Kendra Spence; Yuan, Shuai; Webster, Katherine E.; Tan, Pang-Ning; Lapierre, Jean-Francois; Collins, Sarah M.; Fergus, C. Emi; Scott, Caren E.; Norton Henry, Emily; Soranno, Patricia A.; Filstrup, Christopher T.; Wagner, Tyler

    2017-01-01

    Understanding broad-scale ecological patterns and processes often involves accounting for regional-scale heterogeneity. A common way to do so is to include ecological regions in sampling schemes and empirical models. However, most existing ecological regions were developed for specific purposes, using a limited set of geospatial features and irreproducible methods. Our study purpose was to: (1) describe a method that takes advantage of recent computational advances and increased availability of regional and global data sets to create customizable and reproducible ecological regions, (2) make this algorithm available for use and modification by others studying different ecosystems, variables of interest, study extents, and macroscale ecology research questions, and (3) demonstrate the power of this approach for the research question—How well do these regions capture regional-scale variation in lake water quality? To achieve our purpose we: (1) used a spatially constrained spectral clustering algorithm that balances geospatial homogeneity and region contiguity to create ecological regions using multiple terrestrial, climatic, and freshwater geospatial data for 17 northeastern U.S. states (~1,800,000 km2); (2) identified which of the 52 geospatial features were most influential in creating the resulting 100 regions; and (3) tested the ability of these ecological regions to capture regional variation in water nutrients and clarity for ~6,000 lakes. We found that: (1) a combination of terrestrial, climatic, and freshwater geospatial features influenced region creation, suggesting that the oft-ignored freshwater landscape provides novel information on landscape variability not captured by traditionally used climate and terrestrial metrics; and (2) the delineated regions captured macroscale heterogeneity in ecosystem properties not included in region delineation—approximately 40% of the variation in total phosphorus and water clarity among lakes was at the regional

  6. [Subchronic toxicity test of genetically modified rice with double antisense starch-branching enzyme gene].

    Science.gov (United States)

    Li, Min; Piao, Jianhua; Yang, Xiaoguang

    2010-07-01

    To observe the sub-chronic toxic effects of the genetically modified rice with double antisense SBE gene. Based on gender and weight, weanling Wistar rats were randomly sorted into five groups: non-genetically modified rice group (group A), genetically modified rice group (group B), half genetically modified rice group (group C), quarter genetically modified rice group (group D) and AIN-93G normal diet group (group E). Indicators were the followings: body weight, food consumption, blood routine, blood biochemical test, organ weight, bone density and pathological examination of organs. At the middle of the experiment, the percentage of monocyte of female group B was less than that of group E (P 0.05), and no notable abnormity in the pathological examination of main organs (P > 0.05). There were no enough evidence to confirm the sub-chronic toxicity of genetically modified rice on rats.

  7. Acute toxicity of copper oxide nanoparticles to Daphnia magna under different test conditions

    DEFF Research Database (Denmark)

    Thit, Amalie; Huggins, Krista; Selck, Henriette

    2017-01-01

    suspensions changed in a way similar to what is known for dissolved Cu: first in ISO standard test conditions (pH 7.8), second with slight acidity (pH 6.5), third in the presence of citric acid, and fourth in the presence of humic acid. For all four exposure conditions, the toxicity of Cu employed...... in the three forms followed the same sequence, i.e., CuSO4 > monodispersed 6 nm CuO ≫ poly-dispersed CuO. The toxicity of all Cu forms decreased from pH 6.5, ≫ pH 7.8, > pH 7.8 + citric acid, to ≫ pH 7.8 + humic acid. This pattern is in agreement with concentrations of Cu2+ calculated using the equilibrium...

  8. Toxicity testing of chemical mixtures: some general aspects and need of international guidelines.

    Science.gov (United States)

    Kappus, H; Yang, R S

    1996-01-01

    The topics discussed by the Working Group on Toxicity Testing of Chemical Mixtures included the following (1) the study designs and results from two real-life exposure scenarios as additional information to the various investigations reported at the conference; (2) the need to take into consideration low-level, long-term exposure (i.e. mimicking human exposure conditions) as well as the issue of limited resources in experimental toxicology studies; (3) the importance of exploring alternative and predictive toxicology methodologies to minimize animal use and to conserve resources; (4) the realization that interactive toxicity should include the consideration of physical and biological agents in addition to chemicals. Two specific studies reported at the conference were also discussed. A number of recommendations were made concerning the planning and implementation of toxicology studies on chemical mixtures.

  9. Evaluation of Complex Toxicity of Canbon Nanotubes and Sodium Pentachlorophenol Based on Earthworm Coelomocytes Test.

    Directory of Open Access Journals (Sweden)

    Yang Yang

    Full Text Available As a standard testing organism in soil ecosystems, the earthworm Eisenia fetida has been used widely in toxicity studies. However, tests at the individual level are time- and animal-consuming, with limited sensitivity. Earthworm coelomocytes are important for the assimilation and elimination of exogenous compounds and play a key role in the processes of phagocytosis and inflammation. In this study, we explored an optimal condition to culture coelomocytes of E. fetida in vitro and investigated the cytotoxicity of multiwalled carbon nanotubes (MWCNTs and sodium pentachlorophenol (PCP-Na using coelomocytes via evaluating lethal toxicity, oxidative stress, membrane damage, and DNA damage. The results showed that coelomocytes can be successfully cultured in vitro in primary under the RPMI-1640 medium with 2-4×104 cells/well (1-2×105 cells/mL in 96-well plates at 25°C without CO2. Both MWCNTs and PCP-Na could cause oxidative damage and produce ROS, an evidence for lipid peroxidation with MDA generation and SOD and CAT activity inhibition at high stress. The two chemicals could separately damage the cell membrane structure, increasing permeability and inhibiting mitochondrial membrane potential (MMP. In addition, our results indicate that PCP-Na may be adsorbed onto MWCNTs and its toxicity on earthworm was accordingly alleviated, while a synergetic effect was revealed when PCP-Na and MWCNTs were added separately. In summary, coelomocyte toxicity in in vitro analysis is a sensitive method for detecting the adverse effects of carbon nanotubes combined with various pollutants.

  10. In Situ Estuarine and Marine Toxicity Testing: A Review, Including Recommendations for Future Use in Ecological Risk Assessment

    Science.gov (United States)

    2009-09-01

    field and microcosms than they do under laboratory test conditions. In the case of tributyltin ( TBT ) exposures in San Diego Bay, he found that...TECHNICAL REPORT 1986 September 2009 In Situ Estuarine and Marine Toxicity Testing A Review, Including Recommendations for Future Use in...Pacific TECHNICAL REPORT 1986 September 2009 In Situ Estuarine and Marine Toxicity Testing A Review, Including Recommendations for Future Use in

  11. Mood and autonomic responses to repeated exposure to the Trier Social Stress Test for Groups (TSST-G).

    Science.gov (United States)

    Boesch, Maria; Sefidan, Sandra; Ehlert, Ulrike; Annen, Hubert; Wyss, Thomas; Steptoe, Andrew; La Marca, Roberto

    2014-05-01

    A group version of the Trier Social Stress Test (TSST-G) was introduced as a standardized, economic and efficient tool to induce a psychobiological stress response simultaneously in a group of subjects. The aim of the present study was to examine the efficacy of the TSST-G to repeatedly induce an affective and autonomic stress response while comparing two alternative protocols for the second examination. Healthy young male recruits participated twice in the TSST-G 10 weeks apart. In the first examination, the TSST-G consisted of a combination of mental arithmetic and a fake job interview (TSST-G-1st; n=294). For the second examination, mental arithmetic was combined with either (a) a defensive speech in response to a false shoplifting accusation (TSST-G-2nd-defence; n=105), or (b) a speech on a more neutral topic selected by the investigators (TSST-G-2nd-presentation; n=100). Affect ratings and salivary alpha-amylase (sAA) were determined immediately before and after the stress test, while heart rate (HR) and heart rate variability (HRV) were measured continuously. TSST-G-1st resulted in a significant increase of negative affect, HR, and sAA, and a significant decrease in positive affect and HRV. TSST-G-2nd, overall, resulted in a significant increase of HR and sAA (the latter only in response to TSST-G-2nd-defence) and a decrease in HRV, while no significant affect alterations were found. When comparing both, TSST-G-2nd-defence and -2nd-presentation, the former resulted in a stronger stress response with regard to HR and HRV. The findings reveal that the TSST-G is a useful protocol to repeatedly evoke an affective and autonomic stress response, while repetition leads to affective but not necessarily autonomic habituation. When interested in examining repeated psychosocial stress reactivity, a task that requires an ego-involving effort, such as a defensive speech, seems to be significantly superior to a task using an impersonal speech. Copyright © 2014 Elsevier

  12. Combined Study of Titanium Dioxide Nanoparticle Transport and Toxicity on Microbial Nitrifying Communities under Single and Repeated Exposures in Soil Columns.

    Science.gov (United States)

    Simonin, Marie; Martins, Jean M F; Uzu, Gaëlle; Vince, Erwann; Richaume, Agnès

    2016-10-04

    Soils are exposed to nanoparticles (NPs) as a result of their increasing use in many commercial products. Adverse effects of NPs on soil microorganisms have been reported in several ecotoxicological studies using microcosms. Although repeated exposures are more likely to occur in soils, most of these previous studies were performed as a single exposure to NPs. Contrary to single contamination, the study of multiple NP contaminations in soils requires the use of specialized setups. Using a soil column experiment, we compared the influence of single and repeated exposures (one, two, or three exposures that resulted in the same final concentration applied) on the transport of titanium dioxide (TiO 2 ) NPs through soil and the effect of these different exposure scenarios on the abundance and activity of soil nitrifying microbial communities after a 2 month incubation. The transport of TiO 2 NPs was very limited under both single and repeated exposures and was highest for the lowest concentration injected during the first application. Significant decreases in nitrification activity and ammonia-oxidizing archaea and bacteria populations were observed only for the repeated exposure scenario (three TiO 2 NP contaminations). These results suggest that, under repeated exposures, the transport of TiO 2 NPs to deep soil layers and groundwater is limited and that a chronic contamination is more harmful for the soil microbiological functioning than a single exposure.

  13. Use of various acute, sublethal and early life-stage tests to evaluate the toxicity of refinery effluents

    International Nuclear Information System (INIS)

    Sherry, J.; Scott, B.; Dutka, B.

    1997-01-01

    The toxicities of effluents from three Ontario, Canada, refineries were assessed with microbes, plants, invertebrates, and fish. Acute toxicity was assessed by the Microtox test, an assay based on electron transport activity in submitochondrial particles, and Daphnia magna (water flea); growth of Selenastrum capricornutum (alga); growth of Lemna minor (aquatic plant); germination of Lactuca sativa (nonaquatic plant); survival, growth, and maturation of Panagrellus redivivus (nematode); and genotoxicity in the SOS-Chromotest. Only the Microtox test and the submitochondrial particle test detected acute toxicity in the effluent samples. Reduced survival and sublethal responses were caused by some effluents, but not all effluents were toxic, and none caused a response in all of the tests applied. The results suggest that the effluent treatment systems used at Ontario refineries have largely eliminated acute toxicity to the organisms in their test battery. Although reduced survival and sublethal effects were detected in some of the effluents, the effects were minor. Some of the tests provided evidence, albeit weak, of variations in the responses of the test organisms to a temporal series of effluent samples. Not unexpectedly, there were also minor differences in the responses of the tests to effluents from the three refineries. The fathead minnow test seems to be a sensitive indicator of the sublethal toxicity of Ontario refinery effluents

  14. Development of a suitable test method for evaluating the toxicity of contaminated soils to earthworms in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, G.L. [Univ. of Guelph, Ontario (Canada); Scroggins, R. [Environment Canada, Gloucester, Ontario (Canada). Method Development and Application Section

    1995-12-31

    Environment Canada has embarked on a five year program to develop, standardize, and validate a battery of soil toxicity tests which can be used to assess the relative toxicity of contaminants in soils to terrestrial organisms. These tests must be applicable to soil conditions typically found in Canadian environments and the test species must be representative of the species of soil invertebrates or plants inhabiting soil ecosystems in Canada. One of the toxicity tests being developed is designed to assess the toxicity of contaminated soils to earthworms. Five of the potential test species belong to the Lumbricidae family and include the Canadian worm (Allobophora calignosa/Aporrectodea tuberculate), the European bark worm (Dendrodtilus rubidus (rubida)), the pink soil worm (Eisenia rosea), the red marsh worm (Lumbricus rubellus), and the Canadian night crawler or dew worm (Lumbricus terrestris). The sixth species, the white pot worm (Enchytraeus albidus), belongs to the Enchytraeidae family. Further assessment reduced the number of representative species to three. Most earthworm test methods have been developed to assess the toxicity of chemically-spiked artificial soils to Eisenia fetida or E. andrei. Test methods have also been developed to assess the relative toxicity of contaminated soils from hazardous waste sites. Comparative acute toxicity data for three species of earthworm exposed to a hydrocarbon contamination will be presented. Comparative toxicity data for the same three species of earthworm will also be presented using test procedures and conditions that have been modified to accommodate biological differences among the species of earthworm. Recommendations regarding test design, methods, and conditions optimal for each test species will be summarized and discussed with respect to the precision of test results.

  15. In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles

    International Nuclear Information System (INIS)

    Park, Margriet V.D.Z.; Annema, Wijtske; Salvati, Anna; Lesniak, Anna; Elsaesser, Andreas; Barnes, Clifford; McKerr, George; Howard, C. Vyvyan; Lynch, Iseult; Dawson, Kenneth A.; Piersma, Aldert H.; Jong, Wim H. de

    2009-01-01

    While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining their ability to inhibit differentiation of embryonic stem cells into spontaneously contracting cardiomyocytes. Four well characterized silica nanoparticles of various sizes were used to investigate whether nanomaterials are capable of inhibition of differentiation in the embryonic stem cell test. Nanoparticle size distributions and dispersion characteristics were determined before and during incubation in the stem cell culture medium by means of transmission electron microscopy (TEM) and dynamic light scattering. Mouse embryonic stem cells were exposed to silica nanoparticles at concentrations ranging from 1 to 100 μg/ml. The embryonic stem cell test detected a concentration dependent inhibition of differentiation of stem cells into contracting cardiomyocytes by two silica nanoparticles of primary size 10 (TEM 11) and 30 (TEM 34) nm while two other particles of primary size 80 (TEM 34) and 400 (TEM 248) nm had no effect up to the highest concentration tested. Inhibition of differentiation of stem cells occurred below cytotoxic concentrations, indicating a specific effect of the particles on the differentiation of the embryonic stem cells. The impaired differentiation of stem cells by such widely used particles warrants further investigation into the potential of these nanoparticles to migrate into the uterus, placenta and embryo and their possible effects on embryogenesis.

  16. Tissue identity testing of cancer by short tandem repeat polymorphism: pitfalls of interpretation in the presence of microsatellite instability.

    Science.gov (United States)

    Much, Melissa; Buza, Natalia; Hui, Pei

    2014-03-01

    Tissue identity testing by short tandem repeat (STR) polymorphism offers discriminating power in resolving tissue mix-up or contamination. However, one caveat is the presence of microsatellite unstable tumors, in which genetic alterations may drastically change the STR wild-type polymorphism leading to unexpected allelic discordance. We examined how tissue identity testing results can be altered by the presence of microsatellite instability (MSI). Eleven cases of MSI-unstable (9 intestinal and 2 endometrial adenocarcinomas) and 10 cases of MSI-stable tumors (all colorectal adenocarcinomas) were included. All had been previously tested by polymerase chain reaction testing at 5 National Cancer Institute (NCI) recommended MSI loci and/or immunohistochemistry for DNA mismatch repair proteins (MLH1, MSH2, MSH6, and PMS2). Tissue identity testing targeting 15 STR loci was performed using AmpF/STR Identifiler Amplification. Ten of 11 MSI-unstable tumors demonstrated novel alleles at 5 to 12 STR loci per case and frequently with 3 or more allelic peaks. However, all affected loci showed identifiable germline allele(s) in MSI-high tumors. A wild-type allelic profile was seen in 7 of 10 MSI-stable tumors. In the remaining 3 cases, isolated novel alleles were present at a unique single locus in addition to germline alleles. Loss of heterozygosity was observed frequently in both MSI-stable (6/11 cases) and MSI-unstable tumors (8/10 cases). In conclusion, MSI may significantly alter the wild-type allelic polymorphism, leading to potential interpretation errors of STR genotyping. Careful examination of the STR allelic pattern, high index of suspicion, and follow-up MSI testing are crucial to avoid erroneous conclusions and subsequent clinical and legal consequences. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Laboratory algal bioassays using PAM fluorometry: effects of test conditions on the determination of herbicide and field sample toxicity.

    Science.gov (United States)

    Sjollema, Sascha B; van Beusekom, Sebastiaan A M; van der Geest, Harm G; Booij, Petra; de Zwart, Dick; Vethaak, A Dick; Admiraal, Wim

    2014-05-01

    Pulse Amplitude Modulation (PAM) fluorometry, based on chlorophyll a fluorescence, is a frequently used technique in algal bioassays to assess toxicity of single compounds or complex field samples. Several test conditions can influence the test results, and because a standardized test protocol is currently lacking, linking the results of different studies is difficult. Therefore, the aim of the present study was to gain insight into the effects of test conditions of laboratory algal bioassays using PAM fluorometry on the outcome of toxicity tests. To this purpose, we described the results from several pilot studies on test development in which information is provided on the effects of the main test factors during the pretest phase, the test preparation, the exposure period, and the actual measurement. The experiments were focused on individual herbicides and complex field samples and included the effects of culturing conditions, cell density, solvent concentration, exposure time, and the presence of actinic light. Several of these test conditions were found to influence the outcome of the toxicity test, and the presented information provides important background information for the interpretation of toxicity results and describes which test conditions should be taken into account when using an algal bioassay with PAM fluorometry. Finally, the application of PAM fluorometry in algal toxicity testing is discussed. © 2014 SETAC.

  18. Photocatalytic oxidation of polycyclic aromatic hydrocarbons: Intermediates identification and toxicity testing

    International Nuclear Information System (INIS)

    Woo, O.T.; Chung, W.K.; Wong, K.H.; Chow, Alex T.; Wong, P.K.

    2009-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic pollutants and their low water solubility limits their degradation in aqueous solution. The presence of water-miscible solvent such as acetone can increase the water solubility of PAHs, however acetone will also affect the degradation of PAH. In this study the effects of acetone on the photocatalytic degradation efficiency and pathways of 5 selected PAHs, namely naphthalene (2 rings), acenaphthylene (3 rings), phenanthrene (3 rings), anthracene (3 rings) and benzo[a]anthracene (4 rings) were investigated. The Microtox toxicity test was used to determine whether the PCO system can completely detoxify the parental PAHs and its intermediates. The addition of 16% acetone can greatly alter the degradation pathway of naphthalene and anthracene. Based on intermediates identified from degradation of the 5 PAHs, the location of parental PAHs attacked by reactive free radicals can be correlated with the localization energies of different positions of the compound. For toxicity analysis, irradiation by UV light was found to induce acute toxicity by generating intermediates/degradation products from PAHs and possibly acetone. Lastly, all PAHs (10 mg l -1 ) can be completely detoxified by titanium dioxide (100 mg l -1 ) within 24 h under UVA irradiation (3.9 mW cm -2 ).

  19. Acute toxicity and inactivation tests of CO2 on invertebrates in drinking water treatment systems.

    Science.gov (United States)

    Yin, Wen-Chao; Zhang, Jin-Song; Liu, Li-Jun; Zhao, Jian-Shu; Li, Tuo

    2011-01-01

    In addition to the esthetic problem caused by invertebrates, researchers are recently starting to be more aware of their potential importance in terms of public health. However, the inactivation methods of invertebrates which could proliferate in drinking water treatment systems are not well developed. The objective of this study is to assess the acute toxicity and inactivation effects of CO2 on familiar invertebrates in water treatment processes. The results of this study revealed that CO2 has a definite toxicity to familiar invertebrates. The values of 24-h LC50 (median lethal concentration) were calculated for each test with six groups of invertebrates. The toxicity of CO2 was higher with increasing concentrations in solution but was lower with the increase in size of the invertebrates. Above the concentration of 1,000 mg/L for the CO2 solution, the 100% inactivation time of all the invertebrates was less than 5 s, and in 15 min, the inactivation ratio showed a gradient descent with a decline in concentration. As seen for Mesocyclops thermocyclopoides, by dosing with a sodium bicarbonate solution first and adding a dilute hydrochloric acid solution 5 min later, it is possible to obtain a satisfactory inactivation effect in the GAC (granular activated carbon) filters.

  20. Green Tea Protects Testes against Atrazine-induced Toxicity in Rat

    Directory of Open Access Journals (Sweden)

    Reza Kheirandish

    2017-06-01

    Full Text Available Background: Atrazine (ATZ is a common herbicide in agriculture for control of grass and broad-leaved weeds. It persists in the environment and causes reproductive problems in both human and animals. The present study was aimed at protective effect of green tea against ATZ toxicity in the reproductive system of male rats. Methods: The present study was performed in Veterinary School, Shahid Bahonar University of Kerman in 2016. ATZ and treatment groups received ATZ daily 200 mg/kg BW orally for 14 d. In addition, 0.2% methanolic green tea extract was administrated in the treatment group. Results: In histopathologic investigation, number of germinal layers reduced in the most seminiferous tubules in the ATZ group and spermatids were absence. Necrotic spermatocytes, spermatids, and spermatozoa were evident in the testicular tubules. In the morphometric measurements, tubular diameter, germinal epithelium height, and meiosis index decreased significantly. Conclusion: Green tea extract had reduced testicular toxicity of atrazine significantly. ATZ induces toxicity through oxidative damage and green tea extract can protect the testes due to antioxidant activity of its polyphenols especially flavonoids.

  1. Acute effects of two different initial heart rates on testing the Repeated Sprint Ability in young soccer players.

    Science.gov (United States)

    Ruscello, B; Briotti, G; Tozzo, N; Partipilo, F; Taraborelli, M; Zeppetella, A; Padulo, J; D'Ottavio, S

    2015-10-01

    The aim of this paper was to investigate the acute effects of two different initial heart rates intensities when testing the repeated sprint ability (RSA) performances in young soccer players. Since there are many kinds of pre-match warm-ups, we chose to take as an absolute indicator of internal load the heart rate reached at the end of two different warm-up protocols (60 vs. 90% HRmax) and to compare the respective RSA performances. The RSA tests were performed on fifteen male soccer players (age: 17.9±1.5 years) with two sets of ten shuttle-sprints (15+15 m) with a 1:3 exercise to rest ratio, in different days (randomized order) with different HR% (60 & 90% HRmax). In order to compare the different sprint performances a Fatigue Index (FI%) was computed, while the blood lactate concentrations (BLa-) were measured before and after testing, to compare metabolic demand. Significant differences among trials within each sets (Psoccer player operates during a real match. This background may be partially reproduced by warming up protocols that, by duration and metabolic commitment, can reproduce conveniently the physiological conditions encountered in a real game (e.g. HRmax≈85-95%; BLa->4 mmol/L(-1)).

  2. Acute toxicity tests using rotifers. 4. Effects of cyst age, temperature, and salinity on the sensitivity of Brachionus calyciflorus

    Energy Technology Data Exchange (ETDEWEB)

    Snell, T.W.; Moffat, B.D.; Janssen, C.; Persoone, G. (University of Tampa, Florida (USA))

    1991-06-01

    Several aspects of the response to toxicants using a standardized toxicity test with the freshwater rotifer Brachionus calyciflorus are described. Test animals are obtained by hatching cysts which produce animals of similar age and physiological condition. The acute toxicity of 28 compounds is described with 24-hr LC50's. The LC50's span five orders of magnitude, from silver at 0.008 mg.liter-1 to benzene at more than 1000 mg.liter-1. Control mortality in 84 tests averaged 2% with a standard deviation of 3%, indicating very consistent test sensitivity. Only once in 84 trials did a test fail because of excessive control mortality, yielding a failure rate of 1.2%. Cyst age from 0 to 18 months had no effect on the sensitivity of neonates to reference toxicants. Both high and low temperatures increased rotifer sensitivity to reference toxicants. Copper sensitivity was greater at 10, 25, and 30 degrees C compared with results at 20 degrees C. Likewise, sodium pentachlorophenol toxicity was greater at 10 and 30 degrees C compared with results at 20 degrees C. Survivorship curves at 25 degrees C of neonates under control conditions indicated that mortality begins at about 30 hr. This places a practical limit on toxicant exposure for the assay of 24 hr. B. calyciflorus cysts hatch at salinities up to 5 ppt and acute toxicity tests using pentachlorophenol at this salinity yielded LC50's about one-half those of standard freshwater. B. calyciflorus is preferred over Brachionus plicatilis for toxicity tests in salinities up to 5 ppt because it is consistently more sensitive.

  3. Review on toxicity testing with marine macroalgae and the need for method standardization--exemplified with copper and phenol.

    Science.gov (United States)

    Eklund, Britta T; Kautsky, Lena

    2003-02-01

    Toxic effects on macroalgae have been compiled. Eighty-two articles have been found in literature during 1959-2000. A total of 120 substances were investigated using 65 different macroalgae species. About one-third of the tested compounds were organic substances (33%), another third metal-organic substances (35%), and the last third were oils (14%), metals (8%), detergents (7.5%) and other inorganic chemicals (2.5%). Half of the substances were only tested once on a single species. Likewise, toxicity data has only been reported for one chemical tested on a single occasion for about half of the 65 species. Thus little is known about the toxic effects on marine macroalgae. The objectives of the previous studies undertaken varied and therefore the toxicity data was presented in numerous ways, e.g. using different exposure times, temperature, light intensity, light regime, salinity, and nutrients, which makes a direct comparison of the data difficult. This review also shows that many stages in the lifecycle of macroalgae are often more sensitive to toxic substances than other aquatic organisms. Consequently, tests using macroalgae may discover toxicity earlier, which would in turn also protect the fauna. If toxic compounds have a negative affect on the distribution and growth of structurally and functionally dominating macroalgae, there may indirectly be a large and harmful influence on the whole marine coastal ecosystem. For this reason tests on macroalgae should be included in control programs along the coasts.

  4. Fourier-transform infrared spectroscopy as a novel approach to providing effect-based endpoints in duckweed toxicity testing.

    Science.gov (United States)

    Hu, Li-Xin; Ying, Guang-Guo; Chen, Xiao-Wen; Huang, Guo-Yong; Liu, You-Sheng; Jiang, Yu-Xia; Pan, Chang-Gui; Tian, Fei; Martin, Francis L

    2017-02-01

    Traditional duckweed toxicity tests only measure plant growth inhibition as an endpoint, with limited effects-based data. The present study aimed to investigate whether Fourier-transform infrared (FTIR) spectroscopy could enhance the duckweed (Lemna minor L.) toxicity test. Four chemicals (Cu, Cd, atrazine, and acetochlor) and 4 metal-containing industrial wastewater samples were tested. After exposure of duckweed to the chemicals, standard toxicity endpoints (frond number and chlorophyll content) were determined; the fronds were also interrogated using FTIR spectroscopy under optimized test conditions. Biochemical alterations associated with each treatment were assessed and further analyzed by multivariate analysis. The results showed that comparable x% of effective concentration (ECx) values could be achieved based on FTIR spectroscopy in comparison with those based on traditional toxicity endpoints. Biochemical alterations associated with different doses of toxicant were mainly attributed to lipid, protein, nucleic acid, and carbohydrate structural changes, which helped to explain toxic mechanisms. With the help of multivariate analysis, separation of clusters related to different exposure doses could be achieved. The present study is the first to show successful application of FTIR spectroscopy in standard duckweed toxicity tests with biochemical alterations as new endpoints. Environ Toxicol Chem 2017;36:346-353. © 2016 SETAC. © 2016 SETAC.

  5. Transgenic Mouse Models Transferred into the Test Tube: New Perspectives for Developmental Toxicity Testing In Vitro?

    Science.gov (United States)

    Kugler, Josephine; Luch, Andreas; Oelgeschläger, Michael

    2016-10-01

    Despite our increasing understanding of molecular mechanisms controlling embryogenesis, the identification and characterization of teratogenic substances still heavily relies on animal testing. Embryonic development depends on cell-autonomous and non-autonomous processes including spatiotemporally regulated extracellular signaling activities. These have been elucidated in transgenic mouse models harboring easily detectable reporter genes under the control of evolutionarily conserved signaling cascades. We propose combining these transgenic mouse models and cells derived thereof with existing alternative toxicological testing strategies. This would enable the plausibility of in vitro data to be verified in light of in vivo data and, ultimately, facilitate regulatory acceptance of in vitro test methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Suitability and repeatability of a photostress recovery test device, the macular test device, macular degeneration TEST DEVICE, detector (MDD-2), for diabetes and diabetic retinopathy assessment

    LENUS (Irish Health Repository)

    Loughman, James

    2013-10-16

    Diabetic retinopathy can result in impaired photostress recovery time despite normal visual acuity and fundoscopic appearance. The Macular Degeneration Detector (MDD-2) is a novel flash photostress recovery time device. In this study, we examine the repeatability of the MDD-2 in normal and diabetic subjects.

  7. 77 FR 43089 - Evaluation of an Up-and-Down Procedure for Acute Dermal Systemic Toxicity Testing: Request for...

    Science.gov (United States)

    2012-07-23

    ... vivo acute dermal systemic toxicity tests. Corresponding acute oral LD 50 data for the same compounds....), estimated LD 50 , and incidence of death and other adverse effects. Background Information on ICCVAM and... tests. DATES: Nominations and test method data for the acute dermal and oral tests should be submitted...

  8. Comparative analysis of the toxic effects of natural toxins and harmful substances produced by conventional processing methods or by irradiation and of toxicity tests

    International Nuclear Information System (INIS)

    Dahlhelm, H.; Arndt, K.; Groeger, G.; Schreiber, G.A.; Boegl, K.W.

    1994-01-01

    In this review, tasks and methods of food toxicology as well as the application of the different toxicity tests for the risk assessment of food ingredients are described. Particular reference is made to short-term genotoxicity tests. Enzymatic digestion and extraction methods for complex foodstuffs which are used in the toxicological testing of foods in in vitro systems are described. Radiolytic products which result from irradiation of foods or components of foodstuffs and corresponding results of toxicity testing are reviewed. Foodstuffs irradiated with doses of up to 10 kGy are regarded as toxicologically safe. A survey of the toxicologically tested irradiated foodstuffs as well as the applied maximum doses are given in tables at the end of chapter 8. Among the great number of toxicological studies of irradiated foods those are especially mentioned which have given rise to discussions on the health risks involved. In addition, the difficulties associated with the testing of toxicity of irradiated foodstuffs in feeding experiments are discussed. Short-term tests used to establish the benotoxicity of irradiated foods and essential results of toxicological testing are also presented in tables. An overview is given of the occurrence, frequency and health risks of natural toxins in foods and harmful substances produced by conventional methods of cooking and preservation, in order to enable a comparison with the health risks of irradiated foods. The relevance of animal experiments and in vitro investigations for the prediction of toxic effects of harmful substances of foodstuffs in man is discussed in the final chapter. (VHE) [de

  9. Low malathion concentrations influence metabolism in Chironomus sancticaroli (Diptera, Chironomidae in acute and chronic toxicity tests

    Directory of Open Access Journals (Sweden)

    Débora Rebechi

    2014-09-01

    Full Text Available Low malathion concentrations influence metabolism in Chironomus sancticaroli (Diptera, Chironomidae in acute and chronic toxicity tests. Organophosphate compounds are used in agro-systems, and in programs to control pathogen vectors. Because they are continuously applied, organophosphates often reach water sources and may have an impact on aquatic life. The effects of acute and chronic exposure to the organophosphate insecticide malathion on the midge Chironomus sancticaroli are evaluated. To that end, three biochemical biomarkers, acetylcholinesterase (AChE, alpha (EST-α and beta (EST-β esterase were used. Acute bioassays with five concentrations of malathion, and chronic bioassays with two concentrations of malathion were carried out. In the acute exposure test, AChE, EST-α and EST-β activities declined by 66, 40 and 37%, respectively, at 0.251 µg L-1 and more than 80% at 1.37, 1.96 and 2.51 µg L-1. In chronic exposure tests, AChE and EST-α activities declined by 28 and 15% at 0.251 µg L-1. Results of the present study show that low concentrations of malathion can influence larval metabolism, indicating high toxicity for Chironomus sancticaroli and environmental risk associated with the use of organophosphates.

  10. Qualification of spontaneous undirected locomotor behavior of fish for sublethal toxicity testing. Part 2. Variability of measurement parameters under toxicant-induced stress

    Energy Technology Data Exchange (ETDEWEB)

    Grillitsch, B.; Vogl, C.; Wytek, R.

    1999-12-01

    Spontaneous locomotor behavior of semiadult zebra fish (Brachydanio rerio) was recorded under sublethal short-term exposure to the anionic technical surfactant, linear alkylbenzene sulfonate (C{sub 10-13}-LAS) and cadmium in single compound tests using an automated video-monitoring and object-tracing system. Vertical position and swimming velocity in the horizontal and vertical directions were used as behavioral measurement parameters. Data were analyzed by different statistical methods. In pairwise comparisons, consistent, statistically significant, and toxicant-induced alterations of locomotor behavior were observed only for test concentrations, which also caused aspectoric symptoms of intoxication. This comparatively low sensitivity of the behavioral indication criteria was related to high variation in the measurement parameters and corresponding high, minimum detectable, statistically significant, and toxicant-induced deviations. In contrast, results obtained by regression analysis showed significant trends in locomotor activity over the range of toxicant concentrations tested. Thus, the findings support the inappropriateness of no observed effect concentrations and the lowest observed effect concentrations as summary measures of toxicity and indicate that the regression analysis approach is superior to the analysis of variance approach.

  11. Toxicity tests with crustaceans for detecting sublethal effects of potential endocrine disrupting chemicals

    DEFF Research Database (Denmark)

    Wollenberger, Leah

    /antagonistic activity with the ecdysteroid-responsive Drosophila melanogaster BII cell line 6) to draft an OECD guideline proposal for testing of chemicals based on the experimental work performed within this study In preliminary investigations with A. tonsa were studied various parameters related to processes......New and updated test methods to detect and characterise endocrine disrupting chemicals are urgently needed for the purpose of environmental risk assessment. Although endocrine disruption in invertebrates has not been studied as extensive as in vertebrates, in particular in fish, numerous reports...... of the present Ph.D. project were: 1) to develop a fully synthetic saltwater medium suitable for laboratory culturing of marine copepods including their feeding organism as well as for toxicity testing 2) to identify sensitive endpoints related to growth, development and reproduction of the pelagic calanoid...

  12. Testing of TSCA [Toxic Substances Control Act] incinerator for destruction of PCBs in uranium contaminated wastes

    International Nuclear Information System (INIS)

    Anderson, R.W.

    1987-01-01

    A Toxic Substances Control Act (TSCA) incinerator for environmentally safe destruction of PCBs and hazardous organic materials contaminated with low level radioactive wastes from seven DOE facilities has been constructed at the Oak Ridge Gaseous Diffusion Plant, and has undergone performance testing with PCB surrogates. The system incorporates state-of-the-art off-gas treatment, a highly instrumented kiln and secondary combustion chamber, and an inert atmosphere solids handling feed system. Release of organic during an upset event, which triggers opening of the secondary combustion chamber relief vent, will be prevented by maintaining excess oxygen in the kiln and a high temperature in the secondary combustion chamber with an operating burner. Mixtures of chlorinated benzenes used in performance testing to simulate destruction of PCB, worst case studies to satisfy regulatory concerns, and implications of performance test results will be discussed. 4 refs

  13. Toxicity tests based on predator-prey and competitive interactions between freshwater macroinvertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, E.J.; Blockwell, S.J.; Pascoe, D. [Univ. of Wales Coll. of Cardiff (United Kingdom)

    1994-12-31

    Simple multi-species toxicity tests based on the predation of Daphnia magna Straus by Hydra oligactis (Pallas) and competition between Gammarus pulex (L.) and Asellus aquaticus (L.) were used to determine the effects of three reference chemicals. Criteria examined included functional responses; time to first captures; handling times (predator/prey systems) and co-existence and growth. The tests which proved most practicable and sensitive (lowest observed effects 0.1, 21, and 80 {micro}g/l for lindane, copper and 3,4 dichloroaniline, respectively) were: (1) predator-prey tests: determining changes in the size-structure of predated D. magna populations and (2) competition tests: measuring the feeding rate of G. pulex competing with A. aquaticus, using a bioassay based on the time-response analysis of the consumption of Artemia salina eggs. The concentration of a chemical which affected particular response criteria was fond to depend on the test system employed. Results of the tests indicated that effects were often not dose-related and that a given criterion could be variously affected by different test concentrations. The complex pattern of responses may be explained in terms of the differential sensitivity of the interacting species and perhaps subtle alteration in strategies. The sensitivity of the bioassay endpoints is compared to those of a range of single species tests, and their value for predicting the impact pollutants may have upon natural freshwater ecosystems is discussed.

  14. The sensitization potential of sunscreen after ablative fractional skin resurfacing using modified human repeated insult patch test.

    Science.gov (United States)

    Boonchai, Waranya; Sathaworawong, Angkana; Wongpraparut, Chanisada; Wanitphakdeedecha, Rungsima

    2015-10-01

    Ablative fractional skin resurfacing has become popular and proven to be useful in treating scars, photoaging and wrinkles. Although post-inflammatory hyperpigmentation (PIH) is the most common complication especially in dark-skinned patients like Asian. Several modalities have been used to overcome the PIH. To determine the sensitization potential of sunscreen applied immediately after ablative fractional skin resurfacing. Sixty volunteers were recruited. Of these 30 subjects were from previous ablative fractional skin resurfacing study who applied broad-spectrum sunscreen containing anti-inflammatory agent starting on the first day after resurfacing and another 30 non-resurfacing subjects had applied the same sunscreen on the intact skin. All subjects were patch/photopatch tested for sensitization study by using modified human repeated insult patch test (HRIPT). There were significantly higher sensitization rate of UV-filter, octocrylene and the sunscreen in resurfacing group than in non-resurfacing group. Early application of sunscreen after ablative fractional skin resurfacing has increased the incidence of sensitization potential of sunscreen. The sunscreen is recommended to start using from D3 after fractional ablative skin resurfacing to ensure the complete recovery of skin barrier and minimize the risk of sensitization.

  15. Influence of enrichment on behavioral and neurogenic effects of antidepressants in Wistar rats submitted to repeated forced swim test.

    Science.gov (United States)

    Possamai, Fernanda; dos Santos, Juliano; Walber, Thais; Marcon, Juliana C; dos Santos, Tiago Souza; Lino de Oliveira, Cilene

    2015-04-03

    Repeated forced swimming test (rFST) may detect gradual effects of antidepressants in adult rats. Antidepressants, as enrichment, affected behavior and neurogenesis in rats. However, the influence of enrichment on behavioral and neurogenic effects of antidepressants is unknown. Here, effects of antidepressants on rFST and hippocampal neurogenesis were investigated in rats under enriched conditions. Behaviors of male Wistar rats, housed from weaning in standard (SE) or enriched environment (EE), were registered during rFST. The rFST consisted of 15min of swimming (pretest) followed by 5min of swimming in the first (test), seventh (retest 1) and fourteenth (retest 2) days after pretest. One hour before the test, rats received an intraperitoneal injection of saline (1ml/kg), fluoxetine (2.5mg/kg) or imipramine (2.5 or 5mg/kg). These treatments were performed daily until the day of the retest 2. After retest 2, rats were euthanized for the identification of markers for neurogenesis in the hippocampus. Fluoxetine or imipramine decreased immobility in retests 1 and 2, as compared to saline. EE abolished these differences. In EE, fluoxetine or imipramine (5mg/kg) reduced immobility time in retest 2, as compared to the test. Independent of the housing conditions, fluoxetine and imipramine (5mg/kg) increased the ratio of immature neurons per progenitor cell in the hippocampus. In summary, antidepressants or enrichment counteracted the high immobility in rFST. Enrichment changed the effects of antidepressants in rFST depending on the type, and the dose of a substance but failed to change neurogenesis in control or antidepressant treated-rats. Effects of antidepressants and enrichment on rFST seemed neurogenesis-independent. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Test-retest repeatability of strength capacity, aerobic power and pericranial tenderness of neck and shoulder muscles in children - relevant for tension-type headache

    DEFF Research Database (Denmark)

    Tornøe, Birte; Andersen, Lars L; Skotte, J H

    2013-01-01

    Frequent or chronic tension-type headache in children is a prevalent and debilitating condition for the child, often leading to medication overuse. To explore the relationship between physical factors and tension-type headache in children, the quality of repeated measures was examined. The aim of...... of the present study was to determine the test-retest repeatability of parameters determining isometric neck and shoulder strength and stability, aerobic power, and pericranial tenderness in children....

  17. Test-retest repeatability of the pupil light response to blue and red light stimuli in normal human eyes using a novel pupillometer

    DEFF Research Database (Denmark)

    Herbst, Kristina; Sander, Birgit; Milea, Dan

    2011-01-01

    In this study, we evaluated the repeatability of pupil responses to colored light stimuli in healthy subjects using a prototype chromatic pupillometer. One eye of 10 healthy subjects was tested twice in the same day using monochromatic light exposure at two selected wavelengths (660 and 470 nm......, we have developed a novel prototype of color pupillometer which demonstrates good repeatability in evoking and recording the pupillary response to a bright blue and red light stimulus....

  18. Test-retest repeatability of the pupil light response to blue and red light stimuli in normal human eyes using a novel pupillometer

    DEFF Research Database (Denmark)

    Herbst, Kristina; Sander, Birgit; Milea, Dan

    2011-01-01

    In this study, we evaluated the repeatability of pupil responses to colored light stimuli in healthy subjects using a prototype chromatic pupillometer. One eye of 10 healthy subjects was tested twice in the same day using monochromatic light exposure at two selected wavelengths (660 and 470¿nm......, we have developed a novel prototype of color pupillometer which demonstrates good repeatability in evoking and recording the pupillary response to a bright blue and red light stimulus....

  19. A Novel Experimental and Modelling Strategy for Nanoparticle Toxicity Testing Enabling the Use of Small Quantities

    Directory of Open Access Journals (Sweden)

    Marinda van Pomeren

    2017-11-01

    Full Text Available Metallic nanoparticles (NPs differ from other metal forms with respect to their large surface to volume ratio and subsequent inherent reactivity. Each new modification to a nanoparticle alters the surface to volume ratio, fate and subsequently the toxicity of the particle. Newly-engineered NPs are commonly available only in low quantities whereas, in general, rather large amounts are needed for fate characterizations and effect studies. This challenge is especially relevant for those NPs that have low inherent toxicity combined with low bioavailability. Therefore, within our study, we developed new testing strategies that enable working with low quantities of NPs. The experimental testing method was tailor-made for NPs, whereas we also developed translational models based on different dose-metrics allowing to determine dose-response predictions for NPs. Both the experimental method and the predictive models were verified on the basis of experimental effect data collected using zebrafish embryos exposed to metallic NPs in a range of different chemical compositions and shapes. It was found that the variance in the effect data in the dose-response predictions was best explained by the minimal diameter of the NPs, whereas the data confirmed that the predictive model is widely applicable to soluble metallic NPs. The experimental and model approach developed in our study support the development of (ecotoxicity assays tailored to nano-specific features.

  20. Assessment of Grape, Plum and Orange Synthetic Food Flavourings Using in vivo Acute Toxicity Tests

    Directory of Open Access Journals (Sweden)

    Ila Monize Sousa Sales

    2017-01-01

    Full Text Available The present study evaluates the acute toxicity of synthetic grape, plum and orange flavourings in root meristem cells of Allium cepa at the doses of 3.5, 7.0 and 14.0 mL/kg and exposure times of 24 and 48 h, and in bone marrow erythrocytes of mice treated orally for seven days with 0.5, 1.0, 2.0, 5.0 and 10.0 mL/kg of flavouring. The results of the plant test showed that grape, plum and orange flavourings, at both exposure times, inhibited cell division and promoted the formation of a significant number of micronuclei and mitotic spindle changes. These alterations were observed in at least one exposure time analysed, demonstrating a significant cytotoxic, genotoxic and mutagenic activity. In mouse bioassay, animals treated with 2.0, 5.0 and 10.0 mL/kg of flavouring died before the seventh day of treatment. The amounts of 0.5 and 1.0 mL/kg of the three additives were cytotoxic to erythrocytes, and treatment with the grape flavouring significantly induced the formation of micronucleated cells in the bone marrow of animals. Therefore, under the study conditions, the grape, plum and orange flavouring additives promoted significant toxicity to cells of the test systems used.

  1. Field and laboratory tests on acute toxicity of cadmium to freshwater crayfish

    Energy Technology Data Exchange (ETDEWEB)

    1986-09-01

    Environmental regulatory standards for cadmium (EPA 1980), like those for most pollutants, are based on acute, laboratory toxicity tests of single species. Such tests can be conducted rapidly and inexpensively in comparison to acute or chronic field studies, but their validity has often been questioned. Laboratory-based criteria are subject to two criticisms: (1) chemical and physical conditions differ greatly in degree and variability from laboratory to field, and (2) species are not isolated, but live in an ecosystem of interacting taxa and biofeedback. To investigate the validity of basing field toxicity standards on laboratory data, the authors subjected the freshwater crayfish Orconectes immunis for 96 h to various levels of cadmium in laboratory aquaria and experimental ponds. The study was designed to evaluate in part the first criticism of lab-based criteria. The studies were conducted concurrently with similar short-term experiments on the fathead minnow, Pimephales promelas, and coincided with studies of chronic cadmium stress on fathead minnows in experimental ponds.

  2. Toxicity of two imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], to standard aquatic test organisms: Role of acetone in the induced toxicity.

    Science.gov (United States)

    Tsarpali, Vasiliki; Dailianis, Stefanos

    2015-07-01

    The main goal of this study was to investigate the toxicity of the imidazolium-based ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium tetrafluoroborate) and [omim][BF4] (1-octyl-3-methylimidazolium tetrafluoroborate), in battery of standard aquatic toxicity test organisms. Specifically, exposure of the algae Scenedesmus rubescens, crustaceans Thamnocephalus platyurus and Artemia franciscana, rotifers Brachionus calyciflorus and Brachionus plicatilis and bivalve Mytilus galloprovincialis to different concentrations of [bmim][BF4], [omim][BF4] and/or a binary mixture of [bmim][BF4]-[omim][BF4] (1:1) with or without acetone (carrier solvent), revealed that solvent can differentially mediate ILs' toxic profile. Acetone's ability to differentially affect ILs' cation's alkyl chain length, as well as the hydrolysis of [BF4(-)] anions was evident. Given that the toxic potency of the tested ILs seemed to be equal or even higher (in some cases) than those of conventional organic solvents, the present study revealed that the characterization of imidazolium-based ILs as "green solvents" should not be generalized, at least in case of their natural occurrence in mixtures with organic solvents, such as acetone. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Repeated Strains, Social Control, Social Learning, and Delinquency: Testing an Integrated Model of General Strain Theory in China

    Science.gov (United States)

    Bao, Wan-Ning; Haas, Ain; Chen, Xiaojin; Pi, Yijun

    2014-01-01

    In Agnew's general strain theory, repeated strains can generate crime and delinquency by reducing social control and fostering social learning of crime. Using a sample of 615 middle-and high-school students in China, this study examines how social control and social learning variables mediate the effect of repeated strains in school and at home on…

  4. The effect of repeated measurements and working memory on the most comfortable level in the ANL test

    DEFF Research Database (Denmark)

    Brännström, K Jonas; Olsen, Steen Østergaard; Holm, Lucas

    2014-01-01

    interleaved methodology during one session using a non-semantic version. Phonological (PWM) and visuospatial working memory (VSWM) was measured. STUDY SAMPLE: Thirty-two normal-hearing adults. RESULTS: Repeated measures ANOVA, intraclass correlations, and the coefficient of repeatability (CR) were used...

  5. Repeatedly heated palm kernel oil induces hyperlipidemia, atherogenic indices and hepatorenal toxicity in rats: Beneficial role of virgin coconut oil supplementation.

    Science.gov (United States)

    Famurewa, Ademola C; Nwankwo, Onyebuchi E; Folawiyo, Abiola M; Igwe, Emeka C; Epete, Michael A; Ufebe, Odomero G

    2017-01-01

    The literature reports that the health benefits of vegetable oil can be deteriorated by repeated heating, which leads to lipid oxidation and the formation of free radicals. Virgin coconut oil (VCO) is emerging as a functional food oil and its health benefits are attributed to its potent polyphenolic compounds. We investigated the beneficial effect of VCO supplementation on lipid profile, liver and kidney markers in rats fed repeatedly heated palm kernel oil (HPO). Rats were divided into four groups (n = 5). The control group rats were fed with   a normal diet; group 2 rats were fed a 10% VCO supplemented diet; group 3 administered 10 ml HPO/kg b.w. orally; group 4 were fed 10% VCO + 10 ml HPO/kg for 28 days. Subsequently, serum markers of liver damage (ALT, AST, ALP and albumin), kidney damage (urea, creatinine and uric acid), lipid profile and lipid ratios as cardiovascular risk indices were evaluated. HPO induced a significant increase in serum markers of liver and kidney damage as well as con- comitant lipid abnormalities and a marked reduction in serum HDL-C. The lipid ratios evaluated for atherogenic and coronary risk indices in rats administered HPO only were remarkably higher than control. It was observed that VCO supplementation attenuated the biochemical alterations, including the indices of cardiovascular risks. VCO supplementation demonstrates beneficial health effects against HPO-induced biochemical alterations in rats. VCO may serve to modulate the adverse effects associated with consumption of repeatedly heated palm kernel oil.

  6. Extraction, identification and quantification of heavy metals in Venice lagoon sediments using toxicity tests with microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Passarini, F.; Rampazzo, G.; Volpi Ghirardini, A.; Sperni, L.; Salizzato, M.; Pavoni, B. [Venice Univ., Venice (Italy). Dipt. di Scienze Ambientali

    2000-02-01

    Sediments are the major sink for metal pollutants in the aquatic ecosystem but also an important source for the release of them in the water. In order to assess the contribution of heavy metals to the total sediment toxicity, a methodology that permits to integrate the chemical approach with a direct toxicological approach has been ste up. Toxicological results using Microtox test are compared with analytical results. [Italian] I sedimenti sono il principale deposito per contaminanti metalli nel''ecosistema acquatico, ma anche una fonte importnate di rilascio nell'acqua. Al fine di valutare il contributo dei metalli pesanti alla tossicita' totale del sedimento, e' stata messa a punto una metodologia che permette di integrare l'appoccio chimico con un approccio tossicologico diretto. I risultati dei test di tossicita' Microtox vengono confrontati con i risultati analitici.

  7. A technique for extracting blood samples from mice in fire toxicity tests

    Science.gov (United States)

    Bucci, T. J.; Hilado, C. J.; Lopez, M. T.

    1976-01-01

    The extraction of adequate blood samples from moribund and dead mice has been a problem because of the small quantity of blood in each animal and the short time available between the animals' death and coagulation of the blood. These difficulties are particularly critical in fire toxicity tests because removal of the test animals while observing proper safety precautions for personnel is time-consuming. Techniques for extracting blood samples from mice were evaluated, and a technique was developed to obtain up to 0.8 ml of blood from a single mouse after death. The technique involves rapid exposure and cutting of the posterior vena cava and accumulation of blood in the peritoneal space. Blood samples of 0.5 ml or more from individual mice have been consistently obtained as much as 16 minutes after apparent death. Results of carboxyhemoglobin analyses of blood appeared reproducible and consistent with carbon monoxide concentrations in the exposure chamber.

  8. Acute toxicity testing of some herbicides-, alkaloids-, and antibiotics-metabolizing soil bacteria in the rat.

    Science.gov (United States)

    Kaiser, A; Classen, H G; Eberspächer, J; Lingens, F

    1981-01-01

    Seven strains of soil bacteria with the ability to metabolize herbicides, alkaloids or antibiotics were tested in rats for acute toxicity. 1. Upon oral administration of 9.0 x 10(8) to 6.6 x 10(10) cells daily during 7 d no adverse reactions were observed. 2. Exposure by air did not lead to specific pulmonary changes. 3. Intracutaneous injection of 7.5 x 10(6) to 1.4 x 10(8) cells did not lead to adverse skin reactions. 4. Intraperitoneal injections up to 10(8) cells per animal did not kill rats although bacteria entered blood. At higher concentrations some mortality occurred partly due to unspecific stress reactions. 5. Animal data and observations on 20 humans being exposed to these strains for 2 months up to 15 years support the view that the bacteria tested are essentially harmless for health.

  9. Effects of invertebrate predators and a pesticide on temporary pond microcosms used for aquatic toxicity testing

    International Nuclear Information System (INIS)

    Barry, Michael J.; Davies, Warren

    2004-01-01

    The effects of increased trophic complexity, through the addition of predatory notonectids (Anisops deanei), on temporary pond microcosms used for aquatic toxicity testing were studied. Replicate microcosms were established using sediment from a dried temporary pond, and treated with one of four concentrations of the organochlorine pesticide endosulfan (0, 1, 10 or 50 μg/L), in the presence or absence of six A. deanei. The tanks were sampled regularly for nine weeks following the addition of the predators and the entire contents of each tank counted after 12 weeks. Analysis using non-metric multidimensional scaling (MDS) and non-parametric MANOVA showed that both Anisops and endosulfan at concentrations >10 μg/L significantly altered community structure. However, an interaction between the effects of Anisops and the effects of endosulfan was not detected. The addition of Anisops did not increase the variability of response and thus did not reduce the sensitivity of the test method

  10. Leach and EP [extraction procedure] toxicity tests on grouted waste from Tank 106-AN

    International Nuclear Information System (INIS)

    Serne, R.J.; Martin, W.J.; Lokken, R.O.; LeGore, V.L.; Lindenmeier, C.W.; Martin, P.F.C.

    1989-09-01

    Pacific Northwest Laboratory is conducting laboratory experiments to produce leach rate data for various waste species that will be contained in grout at Hanford. In the work reported here, grout made from Tank 106-AN liquid waste was used to produce empirical leach rate data for several radionuclides ( 60 Co, 90 Sr, 99Tc, 129I, 137Cs, and 241 Am), stable major components (NO 3 - , NO 2 - , F, Cl, and Na), and trace metals (Cr, Mo, and Ni). Two types of tests were used to produce leach rate data: an intermittent replacement leach test (ANS 16.1 leach test) and a static leach test. Measured effective diffusivities of key species are as follows: 4 to 6 x 10 -8 cm 2 /sec for 99 Tc, 3 to 7 x 10 -8 cm 2 /sec for 129 I, 4 to 6 x 10 -9 cm 2 /sec for nitrate, and 6 to 7 x 10 -9 cm 2 /sec for nitrite. The leach indices of all species studied are above (more favorable than) the waste form criteria. The leach indices for 99 Tc and 129 I are 7.4 ± 1.2 and 7.6 ± 0.4, respectively, and are being further investigated in continuing studies of double-shell slurry feed grouts. An Extraction Procedure (EP) toxicity test was also conducted and the grouted water is considered nontoxic per this test protocol. 19 refs., 9 figs., 8 tabs

  11. Toxicity testing of four silver nanoparticle-coated dental castings in 3-D LO2 cell cultures.

    Science.gov (United States)

    Zhao, Yi-Ying; Chu, Qiang; Shi, Xu-Er; Zheng, Xiao-Dong; Shen, Xiao-Ting; Zhang, Yan-Zhen

    To address the controversial issue of the toxicity of dental alloys and silver nanoparticles in medical applications, an in vivo-like LO2 3-D model was constructed within polyvinylidene fluoride hollow fiber materials to mimic the microenvironment of liver tissue. The use of microscopy methods and the measurement of liver-specific functions optimized the model for best cell performances and also proved the superiority of the 3-D LO2 model when compared with the traditional monolayer model. Toxicity tests were conducted using the newly constructed model, finding that four dental castings coated with silver nanoparticles were toxic to human hepatocytes after cell viability assays. In general, the toxicity of both the castings and the coated silver nanoparticles aggravated as time increased, yet the nanoparticles attenuated the general toxicity by preventing metal ion release, especially at high concentrations.

  12. Single and repeated GnRH agonist stimulation tests compared with basal markers of ovarian reserve in the prediction of outcome in IVF

    NARCIS (Netherlands)

    Hendriks, D.J.; Broekmans, F.J.M.; Bancsi, L.F.J.M.M.; Looman, C.W.N.; Jong, F.H. de; Velde, E.R. te

    Purpose: To study the value of a single or repeated GnRH agonist stimulation test (GAST) in predicting outcome in IVF compared to basal ovarian reserve tests. Methods: A total of 57 women was included. In a cycle prior to the IVF treatment, on day 3, an antral follicle count (AFC) was performed

  13. Effects of different base agents on prediction of skin irritation by sodium lauryl sulfate using patch testing and repeated application test.

    Science.gov (United States)

    Horita, Kotomi; Horita, Daisuke; Tomita, Hiroyuki; Yasoshima, Mitsue; Yagami, Akiko; Matsunaga, Kayoko

    2017-05-01

    Animal testing for cosmetics was banned in the European Union (EU) in 2013; therefore, human tests to predict and ensure skin safety such as the patch test or usage test are now in demand in Japan as well as in the EU. In order to investigate the effects of different bases on the findings of tests to predict skin irritation, we performed patch testing (PT) and the repeated application test (RAT) using sodium lauryl sulfate (SLS), a well-known irritant, dissolved in 6 different base agents to examine the effects of these bases on skin irritation by SLS. The bases for PT were distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream. The concentrations of SLS were 0.2% and 0.5%. Twelve different base combinations were applied to the normal back skin of 19 individuals for 24h. RAT was performed with distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream containing SLS at concentrations of 0.2%, 2%, and 5%, being applied to the arms of the same PT subjects. The test preparation of each base was applied at the same site, with 0.2% SLS being used in the first week, 2% SLS in the following week, and 5% SLS in the final week. The results of PT revealed that skin irritation scores varied when SLS at the same concentration was dissolved in a different base. The results of RAT showed that although skin irritation appeared with every base at a concentration of 5%, the positive rate was approximately the same. In conclusion, our results suggest that skin irritation elicited in PT depends on the base, while in RAT, it does not depend on the type of base employed. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Aqueous CO2 vs. aqueous extraction of soils as a preparative procedure for acute toxicity testing

    International Nuclear Information System (INIS)

    Yates, G.W.; Burks, S.L.

    1994-01-01

    This study was to determine if contaminated soils extracted with supercritical CO 2 (SFE) would yield different results from soils extracted with an aqueous media. Soil samples from an abandoned oil refinery were subjected to aqueous and SFE extraction. Uncontaminated control sites were compared with contaminated sites. Each extract was analyzed for 48 hour acute Ceriodaphnia LC50s and Microtox reg-sign EC50s. Comparisons were then made between the aqueous extracts and the SFE extracts. An additional study was made with HPLC chromatographs of the SFE contaminated site extracts to determine if there was a correlation between LC50 results and peak area of different sections of the chromatograph. The 48 hour Ceriodaphnia LC50 of one contaminated site showed a significant increase in toxicity with the supercritical extract compared to the aqueous extract. All contaminated sites gave toxic responses with the supercritical procedure. The Microtox reg-sign assay showed a toxic response with 2 of the 3 contaminated sites for both aqueous and SFE extracts. Results indicate that the Ceriodaphnia assays were more sensitive than Microtox reg-sign to contaminants found in the refinery soil. SFE controls did not show adverse effects with the Ceriodaphnia, but did have a slight effect with Microtox reg-sign. The best correlation (r 2 > 0.90) between the Ceriodaphnia LC50s and the peak areas of the chromatographs was obtained for sections with an estimated log K ow of 1 to 5. SFE extraction provided a fast, efficient and inexpensive method of collecting and testing moderately non-polar to strongly non-polar organic contaminants from contaminated soils

  15. Oak Ridge Toxic Substances Control Act (TSCA) Incinerator test bed for continuous emissions monitoring systems (CEMS)

    International Nuclear Information System (INIS)

    Gibson, L.V. Jr.

    1997-01-01

    The Toxic Substances Control Act (TSCA) Incinerator, located on the K-25 Site at Oak Ridge, Tennessee, continues to be the only operational incinerator in the country that can process hazardous and radioactively contaminated polychlorinated biphenyl (PCB) waste. During 1996, the US Department of Energy (DOE) Environmental Management Office of Science and Technology (EM-50) and Lockheed Martin Energy Systems established a continuous emissions monitoring systems (CEMS) test bed and began conducting evaluations of CEMS under development to measure contaminants from waste combustion and thermal treatment stacks. The program was envisioned to promote CEMS technologies meeting requirements of the recently issued Proposed Standards for Hazardous Waste Combustors as well as monitoring technologies that will allay public concerns about mixed waste thermal treatment and accelerate the development of innovative treatment technologies. Fully developed CEMS, as well as innovative continuous or semi-continuous sampling systems not yet interfaced with a pollutant analyzer, were considered as candidates for testing and evaluation. Complementary to other Environmental Protection Agency and DOE sponsored CEMS testing and within compliant operating conditions of the TSCA Incinerator, prioritization was given to multiple metals monitors also having potential to measure radionuclides associated with particulate emissions. In August 1996, developers of two multiple metals monitors participated in field activities at the incinerator and a commercially available radionuclide particulate monitor was acquired for modification and testing planned in 1997. This paper describes the CEMS test bed infrastructure and summarizes completed and planned activities

  16. Elimination of Whole Effluent Toxicity NPDES Permit Limits through the Use of an Alternative Testing Species and Reasonable Potential Analysis

    International Nuclear Information System (INIS)

    PAYNE, W.L.

    2004-01-01

    The cladoceran, Ceriodaphnia dubia (C. dubia), is required by the State of South Carolina to be used in whole effluent toxicity (WET) compliance tests in order to meet limits contained within National Pollutant Discharge Elimination System (NPDES) permits. Westinghouse Savannah River Company (WSRC) experienced WET test failures for no clear reason over a long period of time. Toxicity identification examinations on effluents did not indicate the presence of toxicants; therefore, the WET test itself was brought under suspicion. Research was undertaken with an alternate cladoceran, Daphnia ambigua (D. ambigua). It was determined that this species survives better in soft water, so approval was obtained from regulating authorities to use this ''alternate'' species in WET tests. The result was better test results and elimination of non-compliances. The successful use of D. ambigua allowed WSRC to gain approval from the South Carolina Department of Health and Environmental Control (SCDHEC) to remove WET limits from the NPDES permit

  17. The mucosal toxicity of different benzalkonium chloride analogues evaluated with an alternative test using slugs.

    Science.gov (United States)

    Adriaens, E; Dierckens, K; Bauters, T G; Nelis, H J; van Goethem, F; Vanparys, P; Remon, J P

    2001-07-01

    The objective of this study was to evaluate the mucosal toxicity of different benzalkonium chloride (BAC) analogues using slugs as the alternative test organism. The effect of different BAC analogues on the mucosal tissue of slugs was determined from the protein, lactate dehydrogenase, and alkaline phosphatase released from the foot mucosa after treatment. Additionally, mucus production and reduction in body weight of the slugs were measured. The eye irritation potency of the molecules was evaluated with the Bovine Corneal Opacity and Permeability (BCOP) assay. The antimicrobial activity of the different BAC analogues was also assessed. All BAC analogues induced severe damage to the mucosal epithelium of the slugs, and the irritation increased with decreasing alkyl chain length: BAC-C16 or = BAC-C16 > BAC-C12. The BAC-C14 exhibited higher activity than the BAC-mix. The toxicity and activity of BAC analogues depend on the alkyl chain length. The use of BAC-C14 as a conservative agent in pharmaceutical preparations instead of the BAC-mix should be considered.

  18. An Exploratory Analysis of Stream Teratogenicity and Human Health Using Zebrafish Whole-Sediment Toxicity Test

    Directory of Open Access Journals (Sweden)

    Matthew Dellinger

    2014-02-01

    Full Text Available This study demonstrates a novel application of effect-based toxicity testing for streams that may provide indications of co-perturbation to ecological and human health. For this study, a sediment contact assay using zebrafish (Danio rerio embryos was adapted to serve as an indicator of teratogenic stress within river sediments. Sediment samples were collected from Lake Michigan tributary watersheds. Sediment contact assay responses were then compared to prevalence of congenital heart disease (CHD and vital statistic birth indicators aggregated from civil divisions associated with the watersheds. Significant risk relationships were detected between variation in early life-stage (ELS endpoints of zebrafish embryos 72 h post-fertilization and the birth prevalence of human congenital heart disease, low birthweight and infant mortality. Examination of principal components of ELS endpoints suggests that variance related to embryo heart and circulatory malformations is most closely associated with human CHD prevalence. Though toxicity assays are sometimes used prospectively, this form of investigation can only be conducted retrospectively. These results support the hypothesis that bioassays normally used for ecological screening can be useful as indicators of environmental stress to humans and expand our understanding of environmental–human health linkages.

  19. Ensuring the Quality of Stem Cell-Derived In Vitro Models for Toxicity Testing.

    Science.gov (United States)

    Stacey, Glyn N; Coecke, Sandra; Price, Anna-Bal; Healy, Lyn; Jennings, Paul; Wilmes, Anja; Pinset, Christian; Ingelman-Sundberg, Magnus; Louisse, Jochem; Haupt, Simone; Kidd, Darren; Robitski, Andrea; Jahnke, Heinz-Georg; Lemaitre, Gilles; Myatt, Glenn

    Quality control of cell cultures used in new in vitro toxicology assays is crucial to the provision of reliable, reproducible and accurate toxicity data on new drugs or constituents of new consumer products. This chapter explores the key scientific and ethical criteria that must be addressed at the earliest stages of developing toxicology assays based on human pluripotent stem cell (hPSC) lines. It also identifies key considerations for such assays to be acceptable for regulatory, laboratory safety and commercial purposes. Also addressed is the development of hPSC-based assays for the tissue and cell types of greatest interest in drug toxicology. The chapter draws on a range of expert opinion within the European Commission/Cosmetics Europe-funded alternative testing cluster SEURAT-1 and consensus from international groups delivering this guidance such as the International Stem Cell Banking Initiative. Accordingly, the chapter summarizes the most up-date best practices in the use and quality control of human Pluripotent Stem Cell lines in the development of in vitro toxicity assays from leading experts in the field.

  20. Tests of rhodamine WT dye for toxicity to oysters and fish

    Science.gov (United States)

    Parker, Garald G.

    1973-01-01

    Because of the toxicity to oyster larvae and eggs of rhodamine B dye in concentrations greater than 1 mg/l in earlier tests, there was a concern that rhodamine WT, a similar tracer dye, would have a detrimental effect on marine life being developed under the aquaculture program of the Lummi Indian Tribe near Bellingham, Wash. Tests showed that 48-hour exposures at 24° C of 11,000 oyster eggs per liter and 6,000 12-day-old larvae per liter, in sea water with concentrations of rhodamine WT ranging from 1 μg/l to 10 mg/l, resulted in development of the eggs to normal straight-hinge larvae and no abnormalities in the larvae development. Tests made on the smolt of both silver salmon and Donaldson trout, with the fish held for 17.5 hours in a tankfull of sea water with a dye concentration of 10 mg/l at 22°C showed no mortalities or respiratory problems. With the concentration increased to 375 mg/l, and the time extended an additional 3.2 hours, still no mortalities or abnormalities were noted. The fish remained healthy in dye-free water when last checked a month after the test.

  1. Antioxidant, Antibacterial activity and Brine shrimp toxicity test of some Mountainous Lichens from Nepal

    Directory of Open Access Journals (Sweden)

    Babita Paudel

    2012-01-01

    Full Text Available A total of twenty four lichen species belonging to six families were collected from mountainous region of Nepal. The methanol extracts of each species were tested for antimicrobial and antioxidant activitiesin vitro. It was found that extracts of twenty one lichen species were active againstB. subtilis and seven species were active againstS. aureus. Similarly, in DPPH assay, three speciesPeltigera sp.,Cladonia sp., andCanoparmelia sp. showed comparable activity with commercial standard, BHA. In ABTS+ assay, extracts ofParmoterma sp.,Ramalina sp.,Peltigera sp. andCladonia sp. showed stronger activity than ascorbic acid. The observed data after comparison with previously published reports indicated that the high altitude lichens contain stronger antioxidant and antibacterial constituents. Similarly, the methanol extracts ofHeterodermia sp. andRamalina sp. showed comparable toxicity effect with commercial standard berberine chloride indicating a potent source of anticancer drugs.

  2. In vitro toxicity test of nano-sized magnesium oxide synthesized via solid-phase transformation

    Science.gov (United States)

    Zheng, Jun; Zhou, Wei

    2018-04-01

    Nano-sized magnesium oxide (MgO) has been a promising potential material for biomedical pharmaceuticals. In the present investigation, MgO nanoparticles synthesized through in-situ solid-phase transformation based on the previous work (nano-Mg(OH)2 prepared by precipitation technique) using magnesium nitrate and sodium hydroxide. The phase structure and morphology of the MgO nanoparticles are characterized by X-ray powder diffraction (XRD), selected area electronic diffraction (SAED) and transmission electron microscopy (TEM) respectively. In vitro hemolysis tests are adopted to evaluate the toxicity of the synthesized nano-MgO. The results evident that nano-MgO with lower concentration is slightly hemolytic, and with concentration increasing nano-MgO exhibit dose-responsive hemolysis.

  3. Working in partnership to advance the 3Rs in toxicity testing

    International Nuclear Information System (INIS)

    Holmes, Anthony M.; Creton, Stuart; Chapman, Kathryn

    2010-01-01

    Toxicological assessment of pharmaceutical and non-pharmaceutical chemicals is a regulatory requirement to ensure all compounds likely to be exposed to humans or the environment are safe. These studies rely on the use of large numbers of animals and involve a number of assumptions and extrapolations that remain controversial in assuring consumer safety. The UK's National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) has taken a collaborative approach to identify opportunities for implementation of the 3Rs principles (Replacement, Reduction and Refinement) to drive innovation and support animal welfare in toxicity testing. This review highlights the mechanisms by which the NC3Rs is working with the pharmaceutical and chemical industries and regulatory authorities to achieve these goals.

  4. Toxicity assessment of industrial chemicals and airborne contaminants: transition from in vivo to in vitro test methods: a review.

    Science.gov (United States)

    Bakand, S; Winder, C; Khalil, C; Hayes, A

    2005-12-01

    Exposure to occupational and environmental contaminants is a major contributor to human health problems. Inhalation of gases, vapors, aerosols, and mixtures of these can cause a wide range of adverse health effects, ranging from simple irritation to systemic diseases. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there are approximately 80,000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from both economical and practical perspectives. While in vitro methods are capable of rapidly providing toxicity information, regulatory agencies in general are still cautious about the replacement of whole-animal methods with new in vitro techniques. Although studying the toxic effects of inhaled chemicals is a complex subject, recent studies demonstrate that in vitro methods may have significant potential for assessing the toxicity of airborne contaminants. In this review, current toxicity test methods for risk evaluation of industrial chemicals and airborne contaminants are presented. To evaluate the potential applications of in vitro methods for studying respiratory toxicity, more recent models developed for toxicity testing of airborne contaminants are discussed.

  5. Bio-testing integral toxicity of corrosion inhibitors, biocides and oil hydrocarbons in oil-and gas-processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Chugunov, V.A.; Kholodenko, V.P.; Irkhina, I.A.; Fomchenkov, V.M.; Novikov, I.A. [State Research Center for Applied Microbiology, Obolensk, Moscow (Russian Federation)

    2004-07-01

    In recent years bioassays have been widely used for assessing levels of contamination of the environment. This is due to the fact that test-organisms provide a general response to toxicants present in samples. Based on microorganisms as test objects, it is possible to develop cheap, sensitive and rapid assays to identify environmental xenobiotics and toxicants. The objective of the research was to develop different microbiological assays for assessing integral toxicity of water environments polluted with corrosion inhibitors, biocides and hydrocarbons in oil- and gas-processing industry. Bio-luminescent, electro-orientational, osmo-optic and microorganism reducing activity assays were used for express evaluation of integral toxicity. They are found to determine promptly integral toxicity of water environments containing various pollutants (oil, oil products, corrosion inhibitors, biocides). Results conclude that the assays may be used for analyzing integral toxicity of water polluted with hydrocarbons, as well as for monitoring of water changes as a result of biodegradation of pollutants by microorganisms and their associations. Using a kit of different assays, it is also possible to evaluate ecological safety of biocides, corrosion inhibitors, and their compositions. Bioassays used as a kit are more effective than each assay individually, allowing one to get complete characterization of a reaction of bacterial test organisms to different environments. (authors)

  6. The SOS-LUX-LAC-FLUORO-Toxicity-test on the International Space Station (ISS).

    Science.gov (United States)

    Rabbow, E; Rettberg, P; Baumstark-Khan, C; Horneck, G

    2003-01-01

    In the 21st century, an increasing number of astronauts will visit the International Space Station (ISS) for prolonged times. Therefore it is of utmost importance to provide necessary basic knowledge concerning risks to their health and their ability to work on the station and during extravehicular activities (EVA) in free space. It is the aim of one experiment of the German project TRIPLE-LUX (to be flown on the ISS) to provide an estimation of health risk resulting from exposure of the astronauts to the radiation in space inside the station as well as during extravehicular activities on one hand, and of exposure of astronauts to unavoidable or as yet unknown ISS-environmental genotoxic substances on the other. The project will (i) provide increased knowledge of the biological action of space radiation and enzymatic repair of DNA damage, (ii) uncover cellular mechanisms of synergistic interaction of microgravity and space radiation and (iii) examine the space craft milieu with highly specific biosensors. For these investigations, the bacterial biosensor SOS-LUX-LAC-FLUORO-Toxicity-test will be used, combining the SOS-LUX-Test invented at DLR Germany (Patent) with the commercially available LAC-FLUORO-Test. The SOS-LUX-Test comprises genetically modified bacteria transformed with the pBR322-derived plasmid pPLS-1. This plasmid carries the promoterless lux operon of Photobacterium leiognathi as a reporter element under control of the DNA-damage dependent SOS promoter of ColD as sensor element. This system reacts to radiation and other agents that induce DNA damages with a dose dependent measurable emission of bioluminescence of the transformed bacteria. The analogous LAC-FLUORO-Test has been developed for the detection of cellular responses to cytotoxins. It is based on the constitutive expression of green fluorescent protein (GFP) mediated by the bacterial protein expression vector pGFPuv (Clontech, Palo Alto, USA). In response to cytotoxic agents, this system

  7. Patterns and predictors of repeat fecal immunochemical and occult blood test screening in four large health care systems in the United States.

    Science.gov (United States)

    Singal, Amit G; Corley, Douglas A; Kamineni, Aruna; Garcia, Michael; Zheng, Yingye; Doria-Rose, Paul V; Quinn, Virginia P; Jensen, Christopher D; Chubak, Jessica; Tiro, Jasmin; Doubeni, Chyke A; Ghai, Nirupa R; Skinner, Celette Sugg; Wernli, Karen; Halm, Ethan A

    2018-02-27

    Effectiveness of fecal occult blood test (FOBT) for colorectal cancer (CRC) screening depends on annual testing, but little is known about patterns of repeat stool-based screening within different settings. Our study's objective was to characterize screening patterns and identify factors associated with repeat screening among patients who completed an index guaiac FOBT (gFOBT) or fecal immunochemical test (FIT). We performed a multi-center retrospective cohort study among people who completed a FOBT between January 2010 and December 2011 to characterize repeat screening patterns over the subsequent 3 years. We studied at 4 large health care delivery systems in the United States. Logistic regression analyses were used to identify factors associated with repeat screening patterns. We included individuals aged 50-71 years who completed an index FOBT and had at least 3 years of follow-up. We excluded people with a history of CRC, colonoscopy within 10 years or flexible sigmoidoscopy within 5 years before the index test, or positive index stool test. Consistent screening was defined as repeat FOBT within every 15 months and inconsistent screening as repeat testing at least once during follow-up but less than consistent screening. Among 959,857 eligible patients who completed an index FIT or gFOBT, 344,103 had three years of follow-up and met inclusion criteria. Of these, 46.6% had consistent screening, 43.4% inconsistent screening, and 10% had no repeat screening during follow-up. Screening patterns varied substantially across healthcare systems, with consistent screening proportions ranging from 1 to 54.3% and no repeat screening proportions ranging from 6.9 to 42.8%. Higher consistent screening proportions were observed in health systems with screening outreach and in-reach programs, whereas the safety-net health system, which uses opportunistic clinic-based screening, had the lowest consistent screening. Consistent screening increased with older age but was less

  8. Comparative Toxicity of Louisiana Sweet Crude Oil (LSC) and Chemically Dispersed LSC to Two Gulf of Mexico Aquatic Test Species.

    Science.gov (United States)

    Environmental Protection Agency released peer reviewed results from the second phase of its independent toxicity testing on mixtures of eight oil dispersants with Louisiana Sweet Crude Oil. EPA conducted the tests as part of an effort to ensure that EPA decisions remain grounded ...

  9. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    International Nuclear Information System (INIS)

    Hoess, S.; Ahlf, W.; Fahnenstich, C.; Gilberg, D.; Hollert, H.; Melbye, K.; Meller, M.; Hammers-Wirtz, M.; Heininger, P.; Neumann-Hensel, H.; Ottermanns, R.; Ratte, H.-T.

    2010-01-01

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  10. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    Energy Technology Data Exchange (ETDEWEB)

    Hoess, S., E-mail: hoess@ecossa.d [Ecossa, Giselastr. 6, 82319 Starnberg (Germany); Institute of Biodiversity - Network (IBN), Dreikronengasse 2, 93047 Regensburg (Germany); Ahlf, W., E-mail: ahlf@tu-harburg.d [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Fahnenstich, C. [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Gilberg, D., E-mail: d-gilberg@ect.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hollert, H., E-mail: henner.hollert@bio5.rwth-aachen.d [Department of Ecosystem Analysis, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Melbye, K. [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Meller, M., E-mail: m-meller@ecotox-consult.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hammers-Wirtz, M., E-mail: hammers-wirtz@gaiac.rwth-aachen.d [Research Institute for Ecosystem Analysis and Assessment (gaiac), RWTH Aachen University, Worringerweg 1, 52056 Aachen (Germany); Heininger, P., E-mail: heininger@bafg.d [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56070 Koblenz (Germany); Neumann-Hensel, H., E-mail: hensel@fintelmann-meyer.d [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Ottermanns, R., E-mail: ottermanns@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Ratte, H.-T., E-mail: toni.ratte@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

    2010-09-15

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  11. Amphipod and Sea Urchin tests to assess the toxicity of Mediterranean sediments: the case of Portmán Bay

    Directory of Open Access Journals (Sweden)

    A. Cesar

    2004-04-01

    Full Text Available The sediment formed by the tailings of an abandoned mine, which discharged into Portmán Bay, Murcia, SE-Spain, was tested to establish a possible gradient of heavy metals. The results were compared with tolerance limits of what was calculated from control sites. Whole sediment toxicity tests were performed on two amphipod species, Gammarus aequicauda and Microdeutopus gryllotalpa, while sediment-water interface and porewater toxicity tests were performed on three sea urchins species, Arbacia lixula, Paracentrotus lividus and Sphaerechinus granularis. The sensitivity of these marine organisms was evaluated by exposure tests using the reference substances: ammonium chloride (NH4Cl, cadmium chloride (CdCl2, potassium dichromate (K2Cr2O7, sodium dodecyl sulfate (C12H25NaO4S and zinc sulfate (ZnSO4. The concentration of heavy metals decreased along the pollution gradient. Amphipod 10 day acute toxicity tests clearly demonstrated the gradient of toxicity. The sediment-water interface tests conducted with sea urchins also pointed to a pollution gradient and were more sensitive than the tests involving amphipods.

  12. Testing the toxicity of metals, phenol, effluents, and receiving waters by root elongation in Lactuca sativa L.

    Science.gov (United States)

    Lyu, Jie; Park, Jihae; Kumar Pandey, Lalit; Choi, Soyeon; Lee, Hojun; De Saeger, Jonas; Depuydt, Stephen; Han, Taejun

    2018-03-01

    Phytotoxicity tests using higher plants are among the most simple, sensitive, and cost-effective of the methods available for ecotoxicity testing. In the present study, a hydroponic-based phytotoxicity test using seeds of Lactuca sativa was used to evaluate the water quality of receiving waters and effluents near two industrial sites (Soyo and Daejon) in Korea with respect to the toxicity of 10 metals (As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, Zn) and phenol, and of the receiving waters and effluents themselves. First, the L. sativa hydroponic bioassay was used to determine whether the receiving water or effluents were toxic; then, the responsible toxicant was identified. The results obtained with the L. sativa bioassay ranked the EC 50 toxicities of the investigated metal ions and phenol as: Cd > Ni > Cu > Zn > Hg > phenol > As > Mn > Cr > Pb > Fe. We found that Zn was the toxicant principally responsible for toxicity in Daejeon effluents. The Daejeon field effluent had a higher Zn concentration than permitted by the effluent discharge criteria of the Ministry of Environment of Korea. Our conclusion on the importance of Zn toxicity was supported by the results of the L. sativa hydroponic assay, which showed that the concentration of Zn required to inhibit root elongation in L. sativa by 50% (EC 50 ) was higher in the Daejeon field effluent than that of pure Zn. More importantly, we proved that the L. sativa hydroponic test method can be applied not only as an alternative tool for determining whether a given waste is acceptable for discharge into public water bodies, but also as an alternative method for measuring the safety of aquatic environments using EC 20 values, with respect to the water pollutants investigated (i.e., Cd, Cr, Cu, Pb, Mn, Hg, Ni, Zn, and phenol). Copyright © 2017. Published by Elsevier Inc.

  13. Multi-parameter in vitro toxicity testing of crizotinib, sunitinib, erlotinib, and nilotinib in human cardiomyocytes

    International Nuclear Information System (INIS)

    Doherty, Kimberly R.; Wappel, Robert L.; Talbert, Dominique R.; Trusk, Patricia B.; Moran, Diarmuid M.; Kramer, James W.; Brown, Arthur M.; Shell, Scott A.; Bacus, Sarah

    2013-01-01

    Tyrosine kinase inhibitors (TKi) have greatly improved the treatment and prognosis of multiple cancer types. However, unexpected cardiotoxicity has arisen in a subset of patients treated with these agents that was not wholly predicted by pre-clinical testing, which centers around animal toxicity studies and inhibition of the human Ether-à-go-go-Related Gene (hERG) channel. Therefore, we sought to determine whether a multi-parameter test panel assessing the effect of drug treatment on cellular, molecular, and electrophysiological endpoints could accurately predict cardiotoxicity. We examined how 4 FDA-approved TKi agents impacted cell viability, apoptosis, reactive oxygen species (ROS) generation, metabolic status, impedance, and ion channel function in human cardiomyocytes. The 3 drugs clinically associated with severe cardiac adverse events (crizotinib, sunitinib, nilotinib) all proved to be cardiotoxic in our in vitro tests while the relatively cardiac-safe drug erlotinib showed only minor changes in cardiac cell health. Crizotinib, an ALK/MET inhibitor, led to increased ROS production, caspase activation, cholesterol accumulation, disruption in cardiac cell beat rate, and blockage of ion channels. The multi-targeted TKi sunitinib showed decreased cardiomyocyte viability, AMPK inhibition, increased lipid accumulation, disrupted beat pattern, and hERG block. Nilotinib, a second generation Bcr-Abl inhibitor, led to increased ROS generation, caspase activation, hERG block, and an arrhythmic beat pattern. Thus, each drug showed a unique toxicity profile that may reflect the multiple mechanisms leading to cardiotoxicity. This study demonstrates that a multi-parameter approach can provide a robust characterization of drug-induced cardiomyocyte damage that can be leveraged to improve drug safety during early phase development. - Highlights: • TKi with known adverse effects show unique cardiotoxicity profiles in this panel. • Crizotinib increases ROS, apoptosis, and

  14. Systemic and immunotoxicity of pristine and PEGylated multi-walled carbon nanotubes in an intravenous 28 days repeated dose toxicity study.

    Science.gov (United States)

    Zhang, Ting; Tang, Meng; Zhang, Shanshan; Hu, Yuanyuan; Li, Han; Zhang, Tao; Xue, Yuying; Pu, Yuepu

    2017-01-01

    The numerous increasing use of carbon nanotubes (CNTs) derived from nanotechnology has raised concerns about their biosafety and potential toxicity. CNTs cause immunologic dysfunction and limit the application of CNTs in biomedicine. The immunological responses induced by pristine multi-walled carbon nanotubes (p-MWCNTs) and PEGylated multi-walled carbon nanotubes (MWCNTs-PEG) on BALB/c mice via an intravenous administration were investigated. The results reflect that the p-MWCNTs induced significant increases in spleen, thymus, and lung weight. Mice treated with p-MWCNTs showed altered lymphocyte populations (CD3 + , CD4 + , CD8 + , and CD19 + ) in peripheral blood and increased serum IgM and IgG levels, and splenic macrophage ultrastructure indicated mitochondria swelling. p-MWCNTs inhibited humoral and cellular immunity function and were associated with decreased immune responses against sheep erythrocytes and serum hemolysis level. Natural killer (NK) activity was not modified by two types of MWCNTs. In comparison with two types of MWCNTs, for a same dose, p-MWCNTs caused higher levels of inflammation and immunosuppression than MWCNTs-PEG. The results of immunological function suggested that after intravenous administration with p-MWCNTs caused more damage to systemic immunity than MWCNTs-PEG. Here, we demonstrated that a surface functional modification on MWCNTs reduces their immune perturbations in vivo. The chemistry-modified MWCNTs change their preferred immune response in vivo and reduce the immunotoxicity of p-MWCNTs.

  15. Toxic Emissions from a Military Test Site in the Territory of Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    Lucio Triolo

    2013-04-01

    Full Text Available This work assesses the environmental impact from chemical emissions due to military tests and routine activities in the area occupied by the Italian Inter-force Test Range (PISQ, located at Salto di Quirra, Sardinia, Italy. After reviewing the military activities carried out at PISQ, such as rocket launching, blasting and armament destruction, projectile and mortar fire impact, the associated pollution is evaluated. Chemical analyses were performed by means of Scanning Electronic Microscopy and Energy Dispersion Spectrometry on biotic and abiotic matrices. Residues of Rb, Tl, W, Ti and Al were found in matrices collected in the PISQ areas and environs. A review of experimental data on air, water, soil, milk, forage and animal tissues obtained by various Public Agencies of Sardinia proved that toxic element residues often exceeded the legal limits. PM10 and PM2.5 air concentrations also exceeded the legal limits after military blasting. Cd and Pb contents in the liver and kidneys of sheep living in farms at PISQ and in control farms that were located more than 20 km away from PISQ were higher than the legal limits. This work was performed to investigate concentration of xenobiotics in ecosystems emitted from PISQ activities. This assessment could be useful to focus future epidemiological studies carried out in PISQ and its neighbouring areas.

  16. Duckweed Lemna minor as a tool for testing toxicity of coal residues and polluted sediments

    Energy Technology Data Exchange (ETDEWEB)

    Jenner, H.A.; Janssen-Mommen, J.P.M. (Kema Environmental Services, Arnhem (Netherlands))

    1993-07-01

    Duckweed, Lemna minor, was used for testing single elements and leachates of coal ashes and sediments by expressing growth as surface coverage. The EC50 for the elements Cd, Cu, Zn, As(III), As(V), Se(IV), Se(VI), SeO[sub 2] were 0.86, 2.2, 4.4, 8.4, 297, 21, 67, 37 [mu]M respectively. Leachates were tested of pulverized coal fuel ash (PFA), including 'low NO[sub x]' ashes, coal gasification slag (CGS), and, as a reference, the polluted sediments of a canal. The concentrations of elements in leachates of 'low NO[sub x]' PFA were higher than those in leachates of conventional PFA. The leaching of anions from PFA was quicker than the cations. CGS showed an absolutely minimal element leaching. Comparison of the effects of conventional PFA with sediments from Rotterdam harbor, River Rhine, and the canal shows PFA to be the far less toxic one. The sediment samples from the canal demonstrated strong growth inhibition, probably due to high zinc concentrations originating from industrial activity.

  17. Duckweed Lemna minor as a tool for testing toxicity of coal residues and polluted sediments

    Energy Technology Data Exchange (ETDEWEB)

    Jenner, H A; Janssen-Mommen, J P.M. [Kema Environmental Services, Arnhem (Netherlands)

    1993-07-01

    Duckweed, Lemna minor, was used for testing single elements and leachates of coal ashes and sediments by expressing growth as surface coverage. The EC50 for the elements Cd, Cu, Zn, As(III), As(V), Se(IV), Se(VI), SeO[sub 2] were 0.86, 2.2, 4.4, 8.4, 297, 21, 67, 37 [mu]M respectively. Leachates were tested of pulverized coal fuel ash (PFA), including 'low NO[sub x]' ashes, coal gasification slag (CGS), and, as a reference, the polluted sediments of a canal. The concentrations of elements in leachates of 'low NO[sub x]' PFA were higher than those in leachates of conventional PFA. The leaching of anions from PFA was quicker than the cations. CGS showed an absolutely minimal element leaching. Comparison of the effects of conventional PFA with sediments from Rotterdam harbor, River Rhine, and the canal shows PFA to be the far less toxic one. The sediment samples from the canal demonstrated strong growth inhibition, probably due to high zinc concentrations originating from industrial activity.

  18. Body-on-a-chip systems for animal-free toxicity testing.

    Science.gov (United States)

    Mahler, Gretchen J; Esch, Mandy B; Stokol, Tracy; Hickman, James J; Shuler, Michael L

    2016-10-01

    Body-on-a-chip systems replicate the size relationships of organs, blood distribution and blood flow, in accordance with human physiology. When operated with tissues derived from human cell sources, these systems are capable of simulating human metabolism, including the conversion of a prodrug to its effective metabolite, as well as its subsequent therapeutic actions and toxic side-effects. The system also permits the measurement of human tissue electrical and mechanical reactions, which provide a measure of functional response. Since these devices can be operated with human tissue samples or with in vitro tissues derived from induced pluripotent stem cells (iPS), they can play a significant role in determining the success of new pharmaceuticals, without resorting to the use of animals. By providing a platform for testing in the context of human metabolism, as opposed to animal models, the systems have the potential to eliminate the use of animals in preclinical trials. This article will review progress made and work achieved as a direct result of the 2015 Lush Science Prize in support of animal-free testing. 2016 FRAME.

  19. Preparation and characterization of nickel-spiked freshwater sediments for toxicity tests: toward more environmentally realistic nickel partitioning

    Science.gov (United States)

    Brumbaugh, William G.; Besser, John M.; Ingersoll, Christopher G.; May, Thomas W.; Ivey, Chris D.; Schlekat, Christian E.; Garman, Emily R.

    2013-01-01

    Two spiking methods were compared and nickel (Ni) partitioning was evaluated during a series of toxicity tests with 8 different freshwater sediments having a range of physicochemical characteristics. A 2-step spiking approach with immediate pH adjustment by addition of NaOH at a 2:1 molar ratio to the spiked Ni was effective in producing consistent pH and other chemical characteristics across a range of Ni spiking levels. When Ni was spiked into sediment having a high acid-volatile sulfide and organic matter content, a total equilibration period of at least 10 wk was needed to stabilize Ni partitioning. However, highest spiking levels evidently exceeded sediment binding capacities; therefore, a 7-d equilibration in toxicity test chambers and 8 volume-additions/d of aerobic overlying water were used to avoid unrealistic Ni partitioning during toxicity testing. The 7-d pretest equilibration allowed excess spiked Ni and other ions from pH adjustment to diffuse from sediment porewater and promoted development of an environmentally relevant, 0.5- to 1-cm oxic/suboxic sediment layer in the test chambers. Among the 8 different spiked sediments, the logarithm of sediment/porewater distribution coefficient values (log Kd) for Ni during the toxicity tests ranged from 3.5 to 4.5. These Kd values closely match the range of values reported for various field Ni-contaminated sediments, indicating that testing conditions with our spiked sediments were environmentally realistic.

  20. Repeated exposure to corticosterone increases depression-like behavior in two different versions of the forced swim test without altering nonspecific locomotor activity or muscle strength.

    Science.gov (United States)

    Marks, Wendie; Fournier, Neil M; Kalynchuk, Lisa E

    2009-08-04

    We have recently shown that repeated high dose injections of corticosterone (CORT) reliably increase depression-like behavior on a modified one-day version of the forced swim test. The main purpose of this experiment was to compare the effect of these CORT injections on our one-day version of the forced swim test and the more traditional two-day version of the test. A second purpose was to determine whether altered behavior in the forced swim test could be due to nonspecific changes in locomotor activity or muscle strength. Separate groups of rats received a high dose CORT injection (40 mg/kg) or a vehicle injection once per day for 21 consecutive days. Then, half the rats from each group were exposed to the traditional two-day forced swim test and the other half were exposed to our one-day forced swim test. After the forced swim testing, all the rats were tested in an open field and in a wire suspension grip strength test. The CORT injections significantly increased the time spent immobile and decreased the time spent swimming in both versions of the forced swim test. However, they had no significant effect on activity in the open field or grip strength in the wire suspension test. These results show that repeated CORT injections increase depression-like behavior regardless of the specific parameters of forced swim testing, and that these effects are independent of changes in locomotor activity or muscle strength.

  1. Is one trial enough for repeated testing? Same-day assessments of walking, mobility and fine hand use in people with myotonic dystrophy type 1.

    Science.gov (United States)

    Kierkegaard, Marie; Petitclerc, Emilie; Hébert, Luc J; Gagnon, Cynthia

    2017-02-01

    Performance-based assessments of physical function are essential in people with myotonic dystrophy type 1 (DM1) to monitor disease progression and evaluate interventions. Commonly used are the six-minute walk test, the 10 m-walk test, the timed up-and-go test, the timed-stands test, grip strength tests and the nine-hole peg test. The number of trials needed on a same-day test occasion and whether the first, best or average of trials should be reported as result is unknown. Thus, the aim was to describe and explore differences between trials in these measures of walking, mobility and fine hand use in 70 adults with DM1. Three trials were performed for each test except for the six-minute walk test where two trials were allowed. There were statistical significant differences over trials in all tests except for the 10 m-walk test and grip strength tests. Pair-wise comparisons showed that the second and third trials were in general better than the first, although effect sizes were small. At which trial the individuals performed their best differed between individuals and tests. People with severe muscular impairment had difficulties to perform repeated trials. Intraclass correlation coefficients were all high in analyses exploring how to report results. The conclusion and clinical implication is that, for a same-day test occasion, one trial is sufficient for the 10 m-walk test and grip strength tests, and that repeated trials should be allowed in the timed up-and-go test, timed-stands test and nine-hole peg tests. We recommend that two trials are performed for these latter tests as such a protocol could accommodate people with various levels of impairments and physical limitations. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Using aquatic macroinvertebrate species traits to build test batteries for sediment toxicity assessment: accounting for the diversity of potential biological responses to toxicants.

    Science.gov (United States)

    Ducrot, Virginie; Usseglio-Polatera, Philippe; Péry, T Alexandre R R; Mouthon, Jacques; Lafont, Michel; Roger, Marie-Claude; Garric, Jeanne; Férard, Jean-François

    2005-09-01

    An original species-selection method for the building of test batteries is presented. This method is based on the statistical analysis of the biological and ecological trait patterns of species. It has been applied to build a macroinvertebrate test battery for the assessment of sediment toxicity, which efficiently describes the diversity of benthic macroinvertebrate biological responses to toxicants in a large European lowland river. First, 109 potential representatives of benthic communities of European lowland rivers were selected from a list of 479 taxa, considering 11 biological traits accounting for the main routes of exposure to a sediment-bound toxicant and eight ecological traits providing an adequate description of habitat characteristics used by the taxa. Second, their biological and ecological trait patterns were compared using coinertia analysis. This comparison allowed the clustering of taxa into groups of organisms that exhibited similar life-history characteristics, physiological and behavioral features, and similar habitat use. Groups exhibited various sizes (7-35 taxa), taxonomic compositions, and biological and ecological features. Main differences among group characteristics concerned morphology, substrate preferendum and habitat utilization, nutritional features, maximal size, and life-history strategy. Third, the best representatives of the mean biological and ecological characteristics of each group were included in the test battery. The final selection was composed of Chironomus riparius (Insecta: Diptera), Branchiura sowerbyi (Oligochaeta: Tubificidae), Lumbriculus variegatus (Oligochaeta: Lumbriculidae), Valvata piscinalis (Gastropoda: Valvatidae), and Sericostoma personatum (Trichoptera: Sericostomatidae). This approach permitted the biological and ecological variety of the battery to be maximized. Because biological and ecological traits of taxa determine species sensitivity, such maximization should permit the battery to better account

  3. Use of butterflies as nontarget insect test species and the acute toxicity and hazard of mosquito control insecticides.

    Science.gov (United States)

    Hoang, Tham C; Pryor, Rachel L; Rand, Gary M; Frakes, Robert A

    2011-04-01

    Honeybees are the standard insect test species used for toxicity testing of pesticides on nontarget insects for the U.S. Environmental Protection Agency (U.S. EPA) under the Federal Insecticide Fungicide and Rodenticide Act (FIFRA). Butterflies are another important insect order and a valued ecological resource in pollination. The current study conducted acute toxicity tests with naled, permethrin, and dichlorvos on fifth larval instar (caterpillars) and adults of different native Florida, USA, butterfly species to determine median lethal doses (24-h LD50), because limited acute toxicity data are available with this major insect group. Thorax- and wing-only applications of each insecticide were conducted. Based on LD50s, thorax and wing application exposures were acutely toxic to both caterpillars and adults. Permethrin was the most acutely toxic insecticide after thorax exposure to fifth instars and adult butterflies. However, no generalization on acute toxicity (sensitivity) of the insecticides could be concluded based on exposures to fifth instars versus adult butterflies or on thorax versus wing exposures of adult butterflies. A comparison of LD50s of the butterflies from this study (caterpillars and adults) with honeybee LD50s for the adult mosquito insecticides on a µg/organism or µg/g basis indicates that several butterfly species are more sensitive to these insecticides than are honeybees. A comparison of species sensitivity distributions for all three insecticides shows that permethrin had the lowest 10th percentile. Using a hazard quotient approach indicates that both permethrin and naled applications in the field may present potential acute hazards to butterflies, whereas no acute hazard of dichlorvos is apparent in butterflies. Butterflies should be considered as potential test organisms when nontarget insect testing of pesticides is suggested under FIFRA. Copyright © 2011 SETAC.

  4. Evidence-based severity assessment: Impact of repeated versus single open-field testing on welfare in C57BL/6J mice.

    Science.gov (United States)

    Bodden, Carina; Siestrup, Sophie; Palme, Rupert; Kaiser, Sylvia; Sachser, Norbert; Richter, S Helene

    2018-01-15

    According to current guidelines on animal experiments, a prospective assessment of the severity of each procedure is mandatory. However, so far, the classification of procedures into different severity categories mainly relies on theoretic considerations, since it is not entirely clear which of the various procedures compromise the welfare of animals, or, to what extent. Against this background, a systematic empirical investigation of the impact of each procedure, including behavioral testing, seems essential. Therefore, the present study was designed to elucidate the effects of repeated versus single testing on mouse welfare, using one of the most commonly used paradigms for behavioral phenotyping in behavioral neuroscience, the open-field test. In an independent groups design, laboratory mice (Mus musculus f. domestica) experienced either repeated, single, or no open-field testing - procedures that are assigned to different severity categories. Interestingly, testing experiences did not affect fecal corticosterone metabolites, body weights, elevated plus-maze or home cage behavior differentially. Thus, with respect to the assessed endocrinological, physical, and behavioral outcome measures, no signs of compromised welfare could be detected in mice that were tested in the open-field repeatedly, once, or, not at all. These findings challenge current classification guidelines and may, furthermore, stimulate systematic research on the severity of single procedures involving living animals. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Repeated testing improves achievement in a blended learning approach for risk competence training of medical students: results of a randomized controlled trial.

    Science.gov (United States)

    Spreckelsen, C; Juenger, J

    2017-09-26

    Adequate estimation and communication of risks is a critical competence of physicians. Due to an evident lack of these competences, effective training addressing risk competence during medical education is needed. Test-enhanced learning has been shown to produce marked effects on achievements. This study aimed to investigate the effect of repeated tests implemented on top of a blended learning program for risk competence. We introduced a blended-learning curriculum for risk estimation and risk communication based on a set of operationalized learning objectives, which was integrated into a mandatory course "Evidence-based Medicine" for third-year students. A randomized controlled trial addressed the effect of repeated testing on achievement as measured by the students' pre- and post-training score (nine multiple-choice items). Basic numeracy and statistical literacy were assessed at baseline. Analysis relied on descriptive statistics (histograms, box plots, scatter plots, and summary of descriptive measures), bootstrapped confidence intervals, analysis of covariance (ANCOVA), and effect sizes (Cohen's d, r) based on adjusted means and standard deviations. All of the 114 students enrolled in the course consented to take part in the study and were assigned to either the intervention or control group (both: n = 57) by balanced randomization. Five participants dropped out due to non-compliance (control: 4, intervention: 1). Both groups profited considerably from the program in general (Cohen's d for overall pre vs. post scores: 2.61). Repeated testing yielded an additional positive effect: while the covariate (baseline score) exhibits no relation to the post-intervention score, F(1, 106) = 2.88, p > .05, there was a significant effect of the intervention (repeated tests scenario) on learning achievement, F(1106) = 12.72, p blended learning approach can be improved significantly by implementing a test-enhanced learning design, namely repeated testing. As

  6. What Is the Role of Paired Rapid Plasma Reagin Testing (Simultaneous Testing of Acute and Convalescent Samples) in the Diagnosis of Repeat Syphilis and the Follow-up of Syphilis?

    Science.gov (United States)

    Kenyon, Chris R; Osbak, Kara Krista; Van Esbroek, Marjan; Lynen, Lutgarde; Crucitti, Tania

    2018-01-01

    Repeat syphilis is playing an increasing role in syphilis transmission in several populations. The assessment of repeat syphilis and response to treatment depends on accurately measuring intraindividual changes in non-treponemal tests. For a 0- to 6-month delta rapid plasma reagin (RPR) to be determined by routine individual RPR testing, samples are tested 6 months apart with differences in reagent batches, environmental conditions, and observers all leading to measurement errors. We hypothesized that conducting paired RPR testing (simultaneous testing of acute and convalescent samples) would enable a more accurate determination of delta RPR compared with individual testing. A total of 120 study participants with a new diagnosis of syphilis were followed up at 0, 3, 6, 9, 12, 18, and 24 months, with RPR testing performed via individual testing at each study visit and at any suspected repeat syphilis. Rapid plasma reagin paired testing was performed on samples from 0 and 6 months and at any suspected repeat syphilis. The quantitative agreement ±1 dilution among paired and individual testing was 97.2%. There was no difference in the proportion with serofast status at 6 months: 21 (19.4%) and 19 (17.6%) according to paired and individual testing, respectively (P = 0.726). There was no statistically significant difference between 0- and 6-month delta RPR as determined by paired and individual testing in predicting seroresponse at 12 months (86.1% and 91.6% agreement with 12-month serofast/nonserofast classification, respectively; P = 0.262). In our setting, individual testing performed equally well compared with paired testing. Follow-up of syphilis will remain onerous for the patient and the health care provider until new tests that can more accurately assess the response to therapy and repeat syphilis/treatment failure are developed.

  7. Applicability of the fish embryo acute toxicity (FET) test (OECD 236) in the regulatory context of Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH).

    NARCIS (Netherlands)

    Sobanska, Marta; Scholz, Stefan; Nyman, Anna-Maija; Cesnaitis, Romanas; Gutierrez Alonso, Simon; Klüver, Nils; Kühne, Ralph; Tyle, Henrik; de Knecht, Joop; Dang, Zhichao; Lundbergh, Ivar; Carlon, Claudio; De Coen, Wim

    In 2013 the Organisation for Economic Co-operation and Development (OECD) test guideline (236) for fish embryo acute toxicity (FET) was adopted. It determines the acute toxicity of chemicals to embryonic fish. Previous studies show a good correlation of FET with the standard acute fish toxicity

  8. Chromium Toxicity Test for Fall Chinook Salmon (Oncorhynchus tshawytscha) Using Hanford Site Groundwater: Onsite Early Life-Stage Toxicity Evaluation

    International Nuclear Information System (INIS)

    Patton, Gregory W; Dauble, Dennis D; Chamness, Mickie A; Abernethy, Cary S; McKinstry, Craig A

    2001-01-01

    The objective of this study was to evaluate site-specific effects for early life-stage (eyed eggs to free swimming juveniles) fall chinook salmon that might be exposed to hexavalent chromium from Hanford groundwater sources. Our exposure conditions included hexavalent chromium obtained from Hanford groundwater wells near the Columbia River, Columbia River water as the diluent, and locally adapted populations of fall chinook salmon. This report describes both a 96-hr pretest using rainbow trout eggs and an early life-stage test beginning with chinook salmon eggs

  9. Toxicity testing of human assisted reproduction devices using the mouse embryo assay.

    NARCIS (Netherlands)

    Punt-Van der Zalm, J.P.; Hendriks, J.C.M.; Westphal, J.R.; Kremer, J.A.M.; Teerenstra, S.; Wetzels, A.M.M.

    2009-01-01

    Systems to assess the toxicity of materials used in human assisted reproduction currently lack efficiency and/or sufficient discriminatory power. The development of 1-cell CBA/B6 F1 hybrid mouse embryos to blastocysts, expressed as blastocyst rate (BR), is used to measure toxicity. The embryos were

  10. The pH dependent toxicity and bioaccumulation of chloroquine tested on S. viminalis (basket willow)

    DEFF Research Database (Denmark)

    Rendal, Cecilie; Trapp, Stefan; Legind, Charlotte Nielsen

    2010-01-01

    (hydroxymethyl) – aminomethane (pH 8 and 9). Concentrations were determined with spectrophotometer. Toxicity was derived from calculations of normalized transpiration over time, and RCF (root concentration factor) values were calculated. Increasing BCF values were found for increasing pH levels, and the toxicity...

  11. Assessment of the safety of hydrogenated resistant maltodextrin: reverse mutation assay, acute and 90-day subchronic repeated oral toxicity in rats, and acute no-effect level for diarrhea in humans.

    Science.gov (United States)

    Yoshikawa, Yuko; Kishimoto, Yuka; Tagami, Hiroyuki; Kanahori, Sumiko

    2013-01-01

    A series of safety assessments were performed on hydrogenated resistant maltodextrin prepared by converting the reducing terminal glucose of resistant maltodextrin into sorbitol. The reverse mutation assay did not show mutagenicity. Acute and 90-day subchronic oral toxicity studies in rats showed no death was observed in any groups, including the group receiving the highest single dose of 10 g/kg body weight or the highest dose of 5 g/kg body weight per day for 90 days. Mucous or watery stools were observed in the hydrogenated resistant maltodextrin treatment group on the acute study, which were transient and were associated with the osmotic pressure caused by intake of the high concentrations. Subchronic study showed dose-dependent increases in the weights of cecum alone, cecal contents alone, and cecum with cecal contents as well as hypertrophy of the cecal mucosal epithelium, which are considered to be common physiological responses after intake of indigestible carbohydrates. These results indicated that the no observed adverse effect level (NOAEL) of hydrogenated resistant maltodextrin was 10 g/kg body weight or more on the acute oral toxicity study and 5.0 g/kg body weight/day or more on the 90-day subchronic repeated oral toxicity study in rats. Further study performed in healthy adult humans showed that the acute no-effect level of hydrogenated resistant maltodextrin for diarrhea was 0.8 g/kg body weight for men and more than 1.0 g/kg body weight for women. The results of the current safety assessment studies suggest that hydrogenated resistant maltodextrin is safe for human consumption.

  12. Evaluating the graphene oxide dispersions for Fish Embryo Toxicity (FET) test

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Zaira; Franqui, Lidiane; Silva, Cristiane A.; Martinez, Diego Stefani Teodoro, E-mail: zairaclemente@hotmail.com [Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP (Brazil); Castro, Vera Lucia Scherholz Salgado [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA), Campinhas, SP (Brazil)

    2016-07-01

    Full text: The Fish Embryo Toxicity (FET) test has wide utilization in nano ecotoxicology. However, some difficulties have been found related to the aggregation and precipitation of nanomaterials in exposure medium and the contrasting results among studies due to differences in the material characteristics. Furthermore, abiotic factors as the presence of organic matter can influence the test evaluation. The aim of this study was to evaluate and characterize the effect of the humic acid presence in the stability of two types of graphene oxide dispersion in an exposure medium used in FET test. Stock-suspensions (1.0 mg mL{sup -1}) of GO (sigma Aldrich, flakes) or base-washed GO (bwGO) and humic acid (HA sodium salt, Sigma Aldrich) were prepared in ultrapure water (UW). They were sonicated before preparing the GO or bwGO test suspensions at 100.0 μg mL{sup -1} in UW and reconstituted water (RW, pH 8±0.2, 425±129 μS/cm), with HA (20.0 μg mL{sup -1})or not. The samples were incubated during 96h at 26 deg C. The GO and bwGO and its dispersions were characterized through the following techniques: spectrophotometry, centrifugation, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), thermogravimetry (TGA), and X-ray photoelectron spectrometry (XPS). The results showed that materials aggregated and precipitated quickly in RW, but in the presence of HA the stability was similar to that found in UW. The aggregation and precipitation of bwGO was more intense than that of GO. The bwGO showed a great particle sizes heterogeneity than GO, in any condition tested. The different behavior can be related to the less presence of oxygenated groups in bwGO regards to GO. These results showed that surface characteristic of GO and the presence of HA influence the GO behavior in exposure medium and support the use of HA as a natural dispersant to graphene oxide in FET test. (author)

  13. Compound-specific effects of diverse neurodevelopmental toxicants on global gene expression in the neural embryonic stem cell test (ESTn)

    International Nuclear Information System (INIS)

    Theunissen, P.T.; Robinson, J.F.; Pennings, J.L.A.; Herwijnen, M.H. van; Kleinjans, J.C.S.; Piersma, A.H.

    2012-01-01

    Alternative assays for developmental toxicity testing are needed to reduce animal use in regulatory toxicology. The in vitro murine neural embryonic stem cell test (ESTn) was designed as an alternative for neurodevelopmental toxicity testing. The integration of toxicogenomic-based approaches may further increase predictivity as well as provide insight into underlying mechanisms of developmental toxicity. In the present study, we investigated concentration-dependent effects of six mechanistically diverse compounds, acetaldehyde (ACE), carbamazepine (CBZ), flusilazole (FLU), monoethylhexyl phthalate (MEHP), penicillin G (PENG) and phenytoin (PHE), on the transcriptome and neural differentiation in the ESTn. All compounds with the exception of PENG altered ESTn morphology (cytotoxicity and neural differentiation) in a concentration-dependent manner. Compound induced gene expression changes and corresponding enriched gene ontology biological processes (GO–BP) were identified after 24 h exposure at equipotent differentiation-inhibiting concentrations of the compounds. Both compound-specific and common gene expression changes were observed between subsets of tested compounds, in terms of significance, magnitude of regulation and functionality. For example, ACE, CBZ and FLU induced robust changes in number of significantly altered genes (≥ 687 genes) as well as a variety of GO–BP, as compared to MEHP, PHE and PENG (≤ 55 genes with no significant changes in GO–BP observed). Genes associated with developmentally related processes (embryonic morphogenesis, neuron differentiation, and Wnt signaling) showed diverse regulation after exposure to ACE, CBZ and FLU. In addition, gene expression and GO–BP enrichment showed concentration dependence, allowing discrimination of non-toxic versus toxic concentrations on the basis of transcriptomics. This information may be used to define adaptive versus toxic responses at the transcriptome level.

  14. Compound-specific effects of diverse neurodevelopmental toxicants on global gene expression in the neural embryonic stem cell test (ESTn)

    Energy Technology Data Exchange (ETDEWEB)

    Theunissen, P.T., E-mail: Peter.Theunissen@rivm.nl [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Robinson, J.F. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Pennings, J.L.A. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Herwijnen, M.H. van [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Kleinjans, J.C.S. [Department of Toxicogenomics, Maastricht University, Maastricht (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Piersma, A.H. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre, Maastricht (Netherlands); Institute for Risk Assessment Sciences, Faculty of Veterinary Sciences, Utrecht University, Utrecht (Netherlands)

    2012-08-01

    Alternative assays for developmental toxicity testing are needed to reduce animal use in regulatory toxicology. The in vitro murine neural embryonic stem cell test (ESTn) was designed as an alternative for neurodevelopmental toxicity testing. The integration of toxicogenomic-based approaches may further increase predictivity as well as provide insight into underlying mechanisms of developmental toxicity. In the present study, we investigated concentration-dependent effects of six mechanistically diverse compounds, acetaldehyde (ACE), carbamazepine (CBZ), flusilazole (FLU), monoethylhexyl phthalate (MEHP), penicillin G (PENG) and phenytoin (PHE), on the transcriptome and neural differentiation in the ESTn. All compounds with the exception of PENG altered ESTn morphology (cytotoxicity and neural differentiation) in a concentration-dependent manner. Compound induced gene expression changes and corresponding enriched gene ontology biological processes (GO–BP) were identified after 24 h exposure at equipotent differentiation-inhibiting concentrations of the compounds. Both compound-specific and common gene expression changes were observed between subsets of tested compounds, in terms of significance, magnitude of regulation and functionality. For example, ACE, CBZ and FLU induced robust changes in number of significantly altered genes (≥ 687 genes) as well as a variety of GO–BP, as compared to MEHP, PHE and PENG (≤ 55 genes with no significant changes in GO–BP observed). Genes associated with developmentally related processes (embryonic morphogenesis, neuron differentiation, and Wnt signaling) showed diverse regulation after exposure to ACE, CBZ and FLU. In addition, gene expression and GO–BP enrichment showed concentration dependence, allowing discrimination of non-toxic versus toxic concentrations on the basis of transcriptomics. This information may be used to define adaptive versus toxic responses at the transcriptome level.

  15. Systemic and immunotoxicity of pristine and PEGylated multi-walled carbon nanotubes in an intravenous 28 days repeated dose toxicity study

    Directory of Open Access Journals (Sweden)

    Zhang T

    2017-02-01

    Full Text Available Ting Zhang,1–3 Meng Tang,1–3 Shanshan Zhang,1–3 Yuanyuan Hu,1–3 Han Li,4 Tao Zhang,4 Yuying Xue,1–3 Yuepu Pu1–3 1Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing, China; 2Jiangsu key Laboratory for Biomaterials and Devices, Southeast University, Nanjing, China; 3Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou, China; 4Department of Material Science and Engineering, National Key Laboratory of Solid State Microstructures, Nanjing University, Nanjing, China Abstract: The numerous increasing use of carbon nanotubes (CNTs derived from nanotechnology has raised concerns about their biosafety and potential toxicity. CNTs cause immunologic dysfunction and limit the application of CNTs in biomedicine. The immunological responses induced by pristine multi-walled carbon nanotubes (p-MWCNTs and PEGylated multi-walled carbon nanotubes (MWCNTs-PEG on BALB/c mice via an intravenous administration were investigated. The results reflect that the p-MWCNTs induced significant increases in spleen, thymus, and lung weight. Mice treated with p-MWCNTs showed altered lymphocyte populations (CD3+, CD4+, CD8+, and CD19+ in peripheral blood and increased serum IgM and IgG levels, and splenic macrophage ultrastructure indicated mitochondria swelling. p-MWCNTs inhibited humoral and cellular immunity function and were associated with decreased immune responses against sheep erythrocytes and serum hemolysis level. Natural killer (NK activity was not modified by two types of MWCNTs. In comparison with two types of MWCNTs, for a same dose, p-MWCNTs caused higher levels of inflammation and immunosuppression than MWCNTs-PEG. The results of immunological function suggested that after intravenous administration with p-MWCNTs caused more damage to systemic immunity than MWCNTs- PEG. Here, we demonstrated that a surface functional modification on MWCNTs reduces

  16. Alternative methods for the median lethal dose (LD(50)) test: the up-and-down procedure for acute oral toxicity.

    Science.gov (United States)

    Rispin, Amy; Farrar, David; Margosches, Elizabeth; Gupta, Kailash; Stitzel, Katherine; Carr, Gregory; Greene, Michael; Meyer, William; McCall, Deborah

    2002-01-01

    The authors have developed an improved version of the up-and-down procedure (UDP) as one of the replacements for the traditional acute oral toxicity test formerly used by the Organisation for Economic Co-operation and Development member nations to characterize industrial chemicals, pesticides, and their mixtures. This method improves the performance of acute testing for applications that use the median lethal dose (classic LD50) test while achieving significant reductions in animal use. It uses sequential dosing, together with sophisticated computer-assisted computational methods during the execution and calculation phases of the test. Staircase design, a form of sequential test design, can be applied to acute toxicity testing with its binary experimental endpoints (yes/no outcomes). The improved UDP provides a point estimate of the LD50 and approximate confidence intervals in addition to observed toxic signs for the substance tested. It does not provide information about the dose-response curve. Computer simulation was used to test performance of the UDP without the need for additional laboratory validation.

  17. Test-retest repeatability of myocardial blood flow and infarct size using 11C-acetate micro-PET imaging in mice

    International Nuclear Information System (INIS)

    Croteau, Etienne; Renaud, Jennifer M.; McDonald, Matthew; Klein, Ran; DaSilva, Jean N.; Beanlands, Rob S.B.; DeKemp, Robert A.

    2015-01-01

    Global and regional responses of absolute myocardial blood flow index (iMBF) are used as surrogate markers to assess response to therapies in coronary artery disease. In this study, we assessed the test-retest repeatability of iMBF imaging, and the accuracy of infarct sizing in mice using 11 C-acetate PET. 11 C-Acetate cardiac PET images were acquired in healthy controls, endothelial nitric oxide synthase (eNOS) knockout transgenic mice, and mice after myocardial infarction (MI) to estimate global and regional iMBF, and myocardial infarct size compared to 18 F-FDG PET and ex-vivo histology results. Global test-retest iMBF values had good coefficients of repeatability (CR) in healthy mice, eNOS knockout mice and normally perfused regions in MI mice (CR = 1.6, 2.0 and 1.5 mL/min/g, respectively). Infarct size measured on 11 C-acetate iMBF images was also repeatable (CR = 17 %) and showed a good correlation with the infarct sizes found on 18 F-FDG PET and histopathology (r 2 > 0.77; p < 0.05). 11 C-Acetate micro-PET assessment of iMBF and infarct size is repeatable and suitable for serial investigation of coronary artery disease progression and therapy. (orig.)

  18. Test-retest repeatability of myocardial blood flow and infarct size using {sup 11}C-acetate micro-PET imaging in mice

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Etienne; Renaud, Jennifer M.; McDonald, Matthew; Klein, Ran; DaSilva, Jean N.; Beanlands, Rob S.B.; DeKemp, Robert A. [University of Ottawa Heart Institute, National Cardiac PET Centre, Ottawa, Ontario (Canada)

    2015-09-15

    Global and regional responses of absolute myocardial blood flow index (iMBF) are used as surrogate markers to assess response to therapies in coronary artery disease. In this study, we assessed the test-retest repeatability of iMBF imaging, and the accuracy of infarct sizing in mice using {sup 11}C-acetate PET. {sup 11}C-Acetate cardiac PET images were acquired in healthy controls, endothelial nitric oxide synthase (eNOS) knockout transgenic mice, and mice after myocardial infarction (MI) to estimate global and regional iMBF, and myocardial infarct size compared to {sup 18}F-FDG PET and ex-vivo histology results. Global test-retest iMBF values had good coefficients of repeatability (CR) in healthy mice, eNOS knockout mice and normally perfused regions in MI mice (CR = 1.6, 2.0 and 1.5 mL/min/g, respectively). Infarct size measured on {sup 11}C-acetate iMBF images was also repeatable (CR = 17 %) and showed a good correlation with the infarct sizes found on {sup 18}F-FDG PET and histopathology (r{sup 2} > 0.77; p < 0.05). {sup 11}C-Acetate micro-PET assessment of iMBF and infarct size is repeatable and suitable for serial investigation of coronary artery disease progression and therapy. (orig.)

  19. Toxicity testing of restorative dental materials using brine shrimp larvae (Artemia salina).

    Science.gov (United States)

    Milhem, Manar M; Al-Hiyasat, Ahmad S; Darmani, Homa

    2008-01-01

    This study investigated the effect of extracts of different composites, glass ionomer cement (GIC)s and compomers on the viability of brine shrimp larvae. Ethanolic extracts of four dental composites (Z-100; Solitaire 2; Filtek P60 and Synergy), a conventional GIC (Ketac-Fil), a resin-modified glass ionomer cement (Vitremer), two compomers (F2000; Dyract AP), and a flowable compomer (Dyract Flow) were prepared from each material. Following evaporation of the ethanol, the extracts were resuspended in distilled water, which was then used to test the effects on the viability of brine shrimp larvae. For the composites, the extract of Synergy was the least toxic (88% viability) followed by the extracts of Solitaire 2, Z100 and P60 (75%, 67.5% and 50% viability, respectively). One-way ANOVA revealed highly significant differences between the resin composite materials (plarvae for the extracts of Ketac-Fil, and Vitremer were 32.3%, and 37.0%, respectively. One-way ANOVA revealed highly significant differences between the groups of materials (pshrimp larvae followed by GICs and then composites.

  20. Development of an in vitro test system for assessment of male, reproductive toxicity.

    Science.gov (United States)

    Habas, Khaled; Anderson, Diana; Brinkworth, Martin

    2014-02-10

    There is a need for improved reproductive toxicology assays that do not require large numbers of animals but are sensitive and informative. Therefore, Staput velocity-sedimentation separation followed by culture of specific mouse testicular cells was used as such a system. The specificity of separation was assessed using immunocytochemistry to identify spermatids, spermatocytes and spermatogonia. The efficacy of the system to detect toxicity was then evaluated by analysing the effects of hydrogen peroxide (H2O2) by the terminal uridine-deoxynucleotide end-labelling (TUNEL) assay to show the rate of apoptosis induced among the different types of germ cells. We found that 2 h of treatment at both 1 and 10 μM induced increases of over ∼10-fold in the percentage of apoptotic cells (p≤0.001), confirming that testicular germ cells are prone to apoptosis at very low concentrations of H2O2. It was also demonstrated for the first time for this compound that spermatogonia are significantly more susceptible than spermatocytes, which are more affected than spermatids. This reflects the proportion of actively dividing cells in these cell types, suggesting a mechanism for the differential sensitivity. The approach should thus form the basis of a useful test system for reproductive and genetic toxicology in the future. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Recommendations for analysis of repeated-measures designs: testing and correcting for sphericity and use of manova and mixed model analysis.

    Science.gov (United States)

    Armstrong, Richard A

    2017-09-01

    A common experimental design in ophthalmic research is the repeated-measures design in which at least one variable is a within-subject factor. This design is vulnerable to lack of 'sphericity' which assumes that the variances of the differences among all possible pairs of within-subject means are equal. Traditionally, this design has been analysed using a repeated-measures analysis of variance (RM-anova) but increasingly more complex methods such as multivariate anova (manova) and mixed model analysis (MMA) are being used. This article surveys current practice in the analysis of designs incorporating different factors in research articles published in three optometric journals, namely Ophthalmic and Physiological Optics (OPO), Optometry and Vision Science (OVS), and Clinical and Experimental Optometry (CXO), and provides advice to authors regarding the analysis of repeated-measures designs. Of the total sample of articles, 66% used a repeated-measures design. Of those articles using a repeated-measures design, 59% and 8% analysed the data using RM-anova or manova respectively and 33% used MMA. The use of MMA relative to RM-anova has increased significantly since 2009/10. A further search using terms to select those papers testing and correcting for sphericity ('Mauchly's test', 'Greenhouse-Geisser', 'Huynh and Feld') identified 66 articles, 62% of which were published from 2012 to the present. If the design is balanced without missing data then manova should be used rather than RM-anova as it gives better protection against lack of sphericity. If the design is unbalanced or with missing data then MMA is the method of choice. However, MMA is a more complex analysis and can be difficult to set up and run, and care should be taken first, to define appropriate models to be tested and second, to ensure that sample sizes are adequate. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

  2. Acute sensitivity of freshwater mollusks and commonly tested invertebrates to select chemicals with different toxic models of action

    Science.gov (United States)

    Previous studies indicate that freshwater mollusks are more sensitive than commonly tested organisms to some chemicals, such as copper and ammonia. Nevertheless, mollusks are generally under-represented in toxicity databases. Studies are needed to generate data with which to comp...

  3. A roadmap for the development of alternative (non-animal) methods for systemic toxicity testing - t4 report

    NARCIS (Netherlands)

    Basketter, D.A.; Clewell, H.; Kimber, I.; Rossi, A.; Blaauboer, B.J.; Burrier, R.; Daneshian, M.; Eskes, C.; Goldberg, A.; Hasiwa, N.

    2012-01-01

    Systemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new products (such as

  4. Evaluation and improvements of a mayfly, Neocloeon (Centroptilum) triangulifer (Ephemeroptera: Baetidae) toxicity test method - SETAC Europe 2016

    Science.gov (United States)

    A recently published test method for Neocloeon triangulifer assessed the survival and growth of larval mayflies exposed to several reference toxicants (NaCl, KCl, and CuSO4). Results were not able to be replicated in subsequent experiments. To identify potential sources of variab...

  5. Quantitative structure–activity relationships for toxicity and genotoxicity of halogenated aliphatic compounds: Wing spot test of Drosophila melanogaster

    Czech Academy of Sciences Publication Activity Database

    Chroust, K.; Pavlová, M.; Prokop, Z.; Mendel, Jan; Božková, K.; Kubát, Z.; Zajíčková, V.; Damborský, J.

    2007-01-01

    Roč. 67, č. 1 (2007), s. 152-159 ISSN 0045-6535 Institutional research plan: CEZ:AV0Z60930519 Keywords : toxicity * wing spot test * QSAR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.739, year: 2007

  6. Proactive behavior, but not inhibitory control, predicts repeated innovation by spotted hyenas tested with a multi-access box.

    Science.gov (United States)

    Johnson-Ulrich, Lily; Johnson-Ulrich, Zoe; Holekamp, Kay

    2018-05-01

    Innovation is widely linked to cognitive ability, brain size, and adaptation to novel conditions. However, successful innovation appears to be influenced by both cognitive factors, such as inhibitory control, and non-cognitive behavioral traits. We used a multi-access box (MAB) paradigm to measure repeated innovation, the number of unique innovations learned across trials, by 10 captive spotted hyenas (Crocuta crocuta). Spotted hyenas are highly innovative in captivity and also display striking variation in behavioral traits, making them good model organisms for examining the relationship between innovation and other behavioral traits. We measured persistence, motor diversity, motivation, activity, efficiency, inhibitory control, and neophobia demonstrated by hyenas while interacting with the MAB. We also independently assessed inhibitory control with a detour cylinder task. Most hyenas were able to solve the MAB at least once, but only four hyenas satisfied learning criteria for all four possible solutions. Interestingly, neither measure of inhibitory control predicted repeated innovation. Instead, repeated innovation was predicted by a proactive syndrome of behavioral traits that included high persistence, high motor diversity, high activity and low neophobia. Our results suggest that this proactive behavioral syndrome may be more important than inhibitory control for successful innovation with the MAB by members of this species.

  7. The sensitivity and reproducibility of the zebrafish (Danio rerio) embryo test for the screening of waste water quality and for testing the toxicity of chemicals.

    Science.gov (United States)

    Lahnsteiner, Franz

    2008-07-01

    The sensitivity of the zebrafish embryo test, a test proposed for routine waste water control, was compared with the acute fish toxicity test, in the determination of six types of waste water and ten different chemicals. The waste water was sampled from the following industrial processes: paper and cardboard production, hide tanning, metal galvanisation, carcass treatment and utilisation, and sewage treatment. The chemicals tested were: dimethylacetamide, dimethylsulphoxide, cadmium chloride, cyclohexane, hydroquinone, mercuric chloride, nickel chloride, nonylphenol, resmethrin and sodium nitrite. For many of the test substances, the zebrafish embryo test and the acute fish toxicity test results showed high correlations. However, there were certain environmentally-relevant substances for which the results of the zebrafish embryo test and the acute fish toxicity test differed significantly, up to 10,000-fold (Hg(2+) > 150-fold difference; NO(2)(-) > 300-fold; Cd(2+) > 200-fold; resmethrin > 10,000-fold). For the investigated waste water samples and chemicals, the survival rate of the zebrafish embryos showed high variations between different egg samples, within the range of the EC50 concentration. Subsequently, 5-6 parallel assays were deemed to be the appropriate number necessary for the precise evaluation of the toxicity of the test substances. Also, it was found that the sensitivities of different ontogenetic stages to chemical exposure differed greatly. During the first 12 hours after fertilisation (4-cell stage to the 5-somite stage), the embryos reacted most sensitively to test substance exposure, whereas the later ontogenetic stages showed only slight or no response, indicating that the test is most sensitive during the first 24 hours post-fertilisation.

  8. Perspective on a Modified Developmental and Reproductive Toxicity Testing Strategy for Cancer Immunotherapy.

    Science.gov (United States)

    Prell, Rodney A; Halpern, Wendy G; Rao, Gautham K

    2016-05-01

    The intent of cancer immunotherapy (CIT) is to generate and enhance T-cell responses against tumors. The tumor microenvironment establishes several inhibitory pathways that lead to suppression of the local immune response, which is permissive for tumor growth. The efficacy of different CITs, alone and in combination, stems from reinvigorating the tumor immune response via several mechanisms, including costimulatory agonists, checkpoint inhibitors, and vaccines. However, immune responses to other antigens (self and foreign) may also be enhanced, resulting in potentially undesired effects. In outbred mammalian pregnancies, the fetus expresses paternally derived alloantigens that are recognized as foreign by the maternal immune system. If unchecked or enhanced, maternal immunity to these alloantigens represents a developmental and reproductive risk and thus is a general liability for cancer immunotherapeutic molecules. We propose a tiered approach to confirm this mechanistic reproductive liability for CIT molecules. A rodent allopregnancy model is based on breeding 2 different strains of mice so that paternally derived alloantigens are expressed by the fetus. When tested with a cross-reactive biotherapeutic, small molecule drug, or surrogate molecule, this model should reveal on-target reproductive liabilities if the pathway is involved in maintaining pregnancy. Alternatively, allopregnancy models with genetically modified mice can be interrogated for exquisitely specific biotherapeutics with restricted species reactivity. The allopregnancy model represents a relatively straightforward approach to confirm an expected on-target reproductive risk for CIT molecules. For biotherapeutics, it could potentially replace more complex developmental and reproductive toxicity testing in nonhuman primates when a pregnancy hazard is confirmed or expected. © The Author(s) 2016.

  9. Repeatability of Cryogenic Multilayer Insulation

    Science.gov (United States)

    Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

    2017-12-01

    Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation (MLI) has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five Glenn Research Center (GRC) provided coupons with 25 layers was shown to be +/- 8.4% whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0%. A second group of 10 coupons has been fabricated by Yetispace and tested by Florida State University, the repeatability between coupons has been shown to be +/- 15-25%. Based on detailed statistical analysis, the data has been shown to be statistically significant.

  10. Acute central nervous system (CNS) toxicity of total body irradiation (TBI) measured using neuropsychological testing of attention functions

    International Nuclear Information System (INIS)

    Wenz, Frederik; Steinvorth, Sarah; Lohr, Frank; Hacke, Werner; Wannenmacher, Michael

    1999-01-01

    Purpose: The purpose of this study was to investigate acute normal tissue damage of low irradiation doses to the healthy, adult central nervous system (CNS) using neuropsychological testing of attention functions. Methods and Materials: Neuropsychological testing (IQ, attention [modified Trail-Making Test A, Digit Symbol Test, D2 Test, Wiener Determination Machine]) was used to examine 40 patients (43 ± 10 years) before and immediately after the first fraction (1.2 Gy) of hyperfractionated total body irradiation (TBI) at the University of Heidelberg. The patients received antiemetic premedication. Test results are given as mean percentiles ± standard deviation, with 50 ± 34 being normal. Thirty-eight control patients (53 ± 15 years) were studied to quantify the influence of hospitalization, stress, and repeated testing. Results: The patients showed normal baseline test results (IQ = 101 ± 14, attention = 54 ± 28) and no decrease in test results after 1.2 Gy TBI. Attention functions improved (66 ± 25) corresponding to a practice effect of repeated testing that was seen in the control group, although alternate versions of the tests were used (IQ = 104 ± 10, attention before = 42 ± 29, attention after = 52 ± 31). Conclusion: Our data show no deterioration of neuropsychologic test results acutely after 1.2 Gy whole body exposure in adult patients without CNS disease receiving antiemetic medication

  11. Testing nanomaterial toxicity in unicellular eukaryotic algae and fish cell lines.

    Science.gov (United States)

    Kroll, Alexandra; Kühnel, Dana; Schirmer, Kristin

    2013-01-01

    ways of deriving a mass balance and quantitative/qualitative information on the uptake and distribution of NM in cells.As NM have a high surface-to-volume ratio and possess specific physical-chemical properties, which make them prone to interfere with various compounds and certain types of toxicity tests, potential interferences and appropriate controls are introduced. Furthermore, different types of dose metrics, which is still a strongly debated issue in nanotoxicology, are highlighted. We also consider laboratory safety regarding NM handling and disposal.

  12. A roadmap for the development of alternative (non-animal) methods for systemic toxicity testing - t4 report

    OpenAIRE

    Basketter, D.A.; Clewell, H.; Kimber, I.; Rossi, A.; Blaauboer, B.J.; Burrier, R.; Daneshian, M.; Eskes, C.; Goldberg, A.; Hasiwa, N.

    2012-01-01

    Systemic toxicity testing forms the cornerstone for the safety evaluation of substances. Pressures to move from traditional animal models to novel technologies arise from various concerns, including: the need to evaluate large numbers of previously untested chemicals and new products (such as nanoparticles or cell therapies), the limited predictivity of traditional tests for human health effects, duration and costs of current approaches, and animal welfare considerations. The latter holds esp...

  13. The chick embryo test as used in the study of the toxicity of certain dithiocarbamates

    NARCIS (Netherlands)

    Gebhardt, D.O.E.; Logten, M.J. van

    1968-01-01

    The toxicities of six dithiocarbamates: bis(dimethyl thiocarbamoyl) disulfide (thiram), zinc dimethyldithiocarbamate (ziram), ferric dimethyldithiocarbamate (ferbam), bis(dimethyl thiocarbamoyl) ethylene bis(dithiocarbamate) (triaram), sodium diethyl dithiocarbamate (NaDEDC), and sodium ethylene

  14. Test-retest repeatability of strength capacity, aerobic power and pericranial tenderness of neck and shoulder muscles in children - relevant for tension-type headache

    Directory of Open Access Journals (Sweden)

    Tornøe B

    2013-08-01

    Full Text Available Birte Tornøe,1,2,5,6 Lars L Andersen,3 Jørgen H Skotte,3 Rigmor Jensen,4 Gunvor Gard,1 Liselotte Skov,2 Inger Hallström1 1Department of Health Sciences, Lund University, Scania, Sweden; 2Children's Headache Clinic, Department of Pediatrics, University of Copenhagen, Herlev Hospital, Herlev, Denmark; 3National Research Centre for the Working Environment, Copenhagen, Denmark; 4Danish Headache Center, Department of Neurology, University of Copenhagen, Glostrup Hospital, Glostrup, Denmark; 5Department of Physiotherapy and Occupational Therapy, University of Copenhagen, Glostrup Hospital, Glostrup, Denmark; 6Department of Physiotherapy, Medical Department, University of Copenhagen, Herlev Hospital, Herlev, Denmark Background: Frequent or chronic tension-type headache in children is a prevalent and debilitating condition for the child, often leading to medication overuse. To explore the relationship between physical factors and tension-type headache in children, the quality of repeated measures was examined. The aim of the present study was to determine the test-retest repeatability of parameters determining isometric neck and shoulder strength and stability, aerobic power, and pericranial tenderness in children. Methods: Twenty-five healthy children, 9 to 18 years of age, participated in test-retest procedures within a 1-week interval. A computerized padded force transducer was used for testing. The tests included the isometric maximal voluntary contraction and force steadiness of neck flexion and extension, and the isometric maximal voluntary contraction and rate of force of the dominant shoulder. Pericranial tenderness was recorded by means of standardized manual palpation, and a submaximal cycle ergometer test predicted maximal oxygen uptake (VO2 max. The measurements were evaluated in steps, using the intraclass correlation coefficient (ICC; changes in the mean between the two test occasions; the levels of agreement, visualized in Bland

  15. Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms

    International Nuclear Information System (INIS)

    Pesce, Stephane; Morin, Soizic; Lissalde, Sophie; Montuelle, Bernard; Mazzella, Nicolas

    2011-01-01

    Polar organic chemical integrative samplers (POCIS) are valuable tools in passive sampling methods for monitoring polar organic pesticides in freshwaters. Pesticides extracted from the environment using such methods can be used to toxicity tests. This study evaluated the acute effects of POCIS extracts on natural phototrophic biofilm communities. Our results demonstrate an effect of POCIS pesticide mixtures on chlorophyll a fluorescence, photosynthetic efficiency and community structure. Nevertheless, the range of biofilm responses differs according to origin of the biofilms tested, revealing spatial variations in the sensitivity of natural communities in the studied stream. Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Research highlights: → Polar organic chemical integrative samplers (POCIS) were used for monitoring polar organic pesticides in a contaminated river. → The acute effects of POCIS extracts were tested on natural phototrophic biofilm communities. → POCIS pesticide mixtures affected chlorophyll a fluorescence, photosynthetic efficiency and community structure. → Biofilm responses differed according to origin of the biofilms tested, revealing variations in the sensitivity of natural communities. → Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment. - Pesticide mixtures extracted from POCIS can affect chl a fluorescence, photosynthetic efficiency and community structure of natural biofilms.

  16. Progress in the development of short term chronic toxicity testing methods for crude oil and commercial bioremediation agents

    International Nuclear Information System (INIS)

    Cavender, R.C.; Cherry, D.S.; Dobbs, M.G.; Bidwell, J.R.; Yeager, M.M.

    1995-01-01

    Proposed modifications to the National Oil and Hazardous Substance Pollution Contingency Plan (NCP) have prompted examinations of the methodology used in toxicity testing of the water soluble fraction of oil, commercial bioremediation agents (CBA), and a combination of the two. The specific concerns addressed by this research are the use of unweathered Alaska North Slope (ANS) crude oil instead of the more expensive, less environmentally realistic distillate ANS-521, and the appropriate laboratory preparation methodology for the water soluble fraction (WSF) used in testing. Seven-day chronic tests exposing the inland silverside (Menidia beryllina) and estuarine mysid (Mysidopsis bahia) to the water soluble fraction of unweathered ANS and ANS-521 showed that mysids responded similarly to the two types of oils while silversides were more sensitive to unweathered ANS. In the presence of a CBA and WSF, the mortality of the organisms and the mysid growth were similar in both types of oil. The NOEC for silverside growth, however, was lower in the combined exposure of a CBA with ANS-521 WSF than it was in the CBA-WSF unweathered ANS. Testing is underway to determine if the stirring time length effects the toxicity of the WSF, or the WSF and CBA combination. In chronic tests using both the silverside and mysid there were no differences in growth and mortality of the organisms tested in WSF prepared from 10 and 20 hours of stirring, however, the 5 hour stirring exposure is less toxic to both organisms

  17. Repeating Marx

    DEFF Research Database (Denmark)

    Fuchs, Christian; Monticelli, Lara

    2018-01-01

    This introduction sets out the context of the special issue “Karl Marx @ 200: Debating Capitalism & Perspectives for the Future of Radical Theory”, which was published on the occasion of Marx’s bicentenary on 5 May 2018. First, we give a brief overview of contemporary capitalism’s development...... and its crises. Second, we argue that it is important to repeat Marx today. Third, we reflect on lessons learned from 200 years of struggles for alternatives to capitalism. Fourth, we give an overview of the contributions in this special issue. Taken together, the contributions in this special issue show...... that Marx’s theory and politics remain key inspirations for understanding exploitation and domination in 21st-century society and for struggles that aim to overcome these phenomena and establishing a just and fair society. We need to repeat Marx today....

  18. Toxicity Test on Malondialdehyde Content and Antioxidant Capacity of Irradiation Sterilization Rendang : In Vitro

    International Nuclear Information System (INIS)

    Zubaidah Irawati; Kamalita Pertiwi; Fransiska Rungkat Zakaria

    2010-01-01

    The safety of irradiated ethnic ready to eat food at high doses raises many questions, and recognized as one of great obstacles in the development of commercialization of food irradiation globally. People are still worried that food treated with irradiation would have induced radioactivity because free radical and its complex derivatives are formed in the irradiation process. Therefore, this study is needed to help understanding the effect of irradiated food on biological system in order to understand the possible effect to human body. The aimed of this research work was to secure the safety of irradiated food at high dose by conducting a toxicity assay using lymphocytes and erythrocytes human blood, and to determine antioxidant capacity of gamma - sterilized rendang at 45 kGy.The methods used were extraction and preparation of rending samples, culture medium preparation, lymphocytes isolation, the assays on lymphocytes proliferation, erythrocytes hemolysis,, antioxidant capacity, and malonaldehyde, respectively. The tested samples were irradiated at PATIR BATAN on 11 th November 2006 (sample A), on 14 th June 2007 (sample B), and “No Label” on 14 th June 2007 (sample C), respectively and non irradiated rending as control was also prepared. The results of proliferation assay showed that irradiated samples did neither inhibit nor induce proliferation significantly. Obviously, hemolysis rate of all samples showed increasing rate with increasing concentration or inversely correlated with dilution neither caused an increase in erythrocytes hemolysis rate nor inhibition in erythrocytes hemolysis significantly. Antioxidant capacity assay in irradiated samples showed higher value than in non-irradiated sample while irradiation treatment did not influence malonaldehyde content in rendang. (author)

  19. EPINEPHRINE CONCENTRATION IN WILD BOAR (SUS SCROFA L. SERUM AFTER REPEATED ELISA TESTED FREEZE-THAWING CYCLES

    Directory of Open Access Journals (Sweden)

    Neška Vukšić

    2013-06-01

    Full Text Available Blood samples for determining of epinephrine concentration and biochemical parameters in the blood serum of wild boars were taken from 42 healthy wild boars, both sexes, during the hunting season. All animals in good condition, body weight 20 to 95 kg, were divided into two groups up to 50 kg (group A and up to 95 kg (Group B. Epinephrine concentration was determined by ELISA twice: one week after taking samples and a month after repeated freezing at -80°C. It was higher in relation to the reference value of domestic pigs and human (109.45 pg/ml in A and 119.54 pg/ml in B group. Repeated freezing and re-analysis after a month were resulted in lower concentrations of epinephrine (12% in young and 11.17% in adult animal, but without statistical significance (P>0.05. Biochemical analysis results’ show increased glucose and triglycerides concentrations compared to the reference values, while other indicators were observed within or slightly increased referring to the normal range. The correlation between glucose and epinephrine was not determined.

  20. Study of the relative toxicity of anions, with Polycelis nigra as test animal

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J R.E.

    1942-01-01

    A brief review is given of existing knowledge regarding the physiological effects of anions, and literature dealing with their relative toxicity. The degree of toxicity of twenty-seven anions to Polycelis nigra (Mueller) has been assessed, by determining in each case the molar concentration the animal survives for 48 hr. at 15-18/sup 0/C. On this basis their order of increasing toxicity is as follows; commas separate ions of similar degree of toxicity: Cltoxic than cations. Even the most toxic anion (OH) is far less toxic than ionic copper, silver, or gold. The respiration rate of Polycelis is heavily depressed by cyanide, but the survival time is three days or longer, as long as the respiration rate is not less than about 16% of the normal value. With further depression the survival time shortens rapidly, and at 9% normal is under 4 hr. The normal respiration rate of Polycelis nigra is 0.165 cc O/sub 2//g./hr. This is not very much less than that of the trout. Polycelis is considerably the more resistant to cyanide. This is probably connected with its capability of surviving very many hours in water containing a very reduced supply of oxygen. 34 references, 6 figures, 1 table.

  1. Quantitative structure-activity relationships for toxicity and genotoxicity of halogenated aliphatic compounds: wing spot test of Drosophila melanogaster.

    Science.gov (United States)

    Chroust, Karel; Pavlová, Martina; Prokop, Zbynek; Mendel, Jan; Bozková, Katerina; Kubát, Zdenek; Zajícková, Veronika; Damborský, Jiri

    2007-02-01

    Halogenated aliphatic compounds were evaluated for toxic and genotoxic effects in the somatic mutation and recombination test employing Drosophila melanogaster. The tested chemicals included chlorinated, brominated and iodinated; mono-, di- and tri-substituted; saturated and unsaturated alkanes: 1,2-dibromoethane, 1-bromo-2-chloroethane, 1-iodopropane, 2,3-dichloropropene, 3-bromo-1-propene, epibromohydrin, 2-iodobutane, 3-chloro-2-methylpropene, 1,2,3-trichloropropane, 1,2-dichloroethane, 1,2-dichlorobutane, 1-chloro-2-methylpropane, 1,3-dichloropropane, 1,2-dichloropropane, 2-chloroethymethylether, 1-bromo-2-methylpropane and 1-chloropentane. N-methyl-N-nitrosourea served as the positive and distilled water as the negative control. The set of chemicals for the toxicological testing was selected by the use of statistical experiment design. Group of unsaturated aliphatic hydrocarbons were generally more toxic than saturated analogues. The genotoxic effect was observed with 14 compounds in the wing spot test, while 3 substances did not show any genotoxicity by using the wing spot test at 50% lethal concentration. The highest number of wing spots was observed in genotoxicity assay with 1-bromo-2-chloroethane, 1,2-dichloroethane, 1,2-dibromoethane and 1-iodopropane. Nucleophilic superdelocalizability calculated by quantum mechanics appears to be a good parameter for prediction of both toxicity and genotoxicity effects of halogenated aliphatic compounds.

  2. Rapid bioassessment methods for assessing vegetation toxicity at the Savannah River Site - germination tests and root elongation trials

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.; Klaine, S.J.; Hook, D.D. [and others

    1996-01-01

    Plants form the basis of all ecosystems including wetlands. Although they are the most abundant life form and are the primary producers for all other organisms, they have received the least attention when it comes to environmental matters. Higher plants have rarely been used in ecotoxicity testing and may not respond in the same manner as algae, which have been used more frequently. The introduction of hazardous waste materials into wetland areas has the potential to alter and damage the ecological processes in these ecosystems. Measuring the impact of these contaminants on higher plants is therefore important and needs further research. Higher plants are useful for detecting both herbicidal toxicity and heavy metal toxicity. For phytotoxicity tests to be practical they must be simple, inexpensive, yet sensitive to a variety of contaminants. A difference between seed germination and root elongation tests is that seed germination tests measure toxicity associated with soils directly, while root elongation tests consider the indirect effects of water-soluble constituents that may be present in site samples.

  3. Toxicity of sediments potentially contaminated by coal mining and natural gas extraction to unionid mussels and commonly tested benthic invertebrates

    Science.gov (United States)

    Wang, Ning; Ingersoll, Christopher G.; Kunz, James L.; Brumbaugh, William G.; Kane, Cindy M.; Evans, R. Brian; Alexander, Steven; Walker, Craig; Bakaletz, Steve

    2013-01-01

    Sediment toxicity tests were conducted to assess potential effects of contaminants associated with coal mining or natural gas extraction activities in the upper Tennessee River basin and eastern Cumberland River basin in the United States. Test species included two unionid mussels (rainbow mussel, Villosa iris, and wavy-rayed lampmussel, Lampsilis fasciola, 28-d exposures), and the commonly tested amphipod, Hyalella azteca (28-d exposure) and midge, Chironomus dilutus (10-d exposure). Sediments were collected from seven test sites with mussel communities classified as impacted and in proximity to coal mining or gas extraction activities, and from five reference sites with mussel communities classified as not impacted and no or limited coal mining or gas extraction activities. Additional samples were collected from six test sites potentially with high concentrations of polycyclic aromatic hydrocarbons (PAHs) and from a test site contaminated by a coal ash spill. Mean survival, length, or biomass of one or more test species was reduced in 10 of 14 test samples (71%) from impacted areas relative to the response of organisms in the five reference samples. A higher proportion of samples was classified as toxic to mussels (63% for rainbow mussels, 50% for wavy-rayed lampmussels) compared with amphipods (38%) or midge (38%). Concentrations of total recoverable metals and total PAHs in sediments did not exceed effects-based probable effect concentrations (PECs). However, the survival, length, or biomasses of the mussels were reduced significantly with increasing PEC quotients for metals and for total PAHs, or with increasing sum equilibrium-partitioning sediment benchmark toxic units for PAHs. The growth of the rainbow mussel also significantly decreased with increasing concentrations of a major anion (chloride) and major cations (calcium and magnesium) in sediment pore water. Results of the present study indicated that (1) the findings from laboratory tests were generally

  4. Rationale and design of REACT: a randomised controlled trial assessing the effectiveness of home-collection to increase chlamydia retesting and detect repeat positive tests.

    Science.gov (United States)

    Smith, Kirsty S; Hocking, Jane S; Chen, Marcus; Fairley, Christopher K; McNulty, Anna; Read, Phillip; Bradshaw, Catriona S; Tabrizi, Sepehr N; Wand, Handan; Saville, Marion; Rawlinson, William; Garland, Suzanne M; Donovan, Basil; Kaldor, John M; Guy, Rebecca

    2014-04-24

    Repeat infection with Chlamydia trachomatis is common and increases the risk of sequelae in women and HIV seroconversion in men who have sex with men (MSM). Despite guidelines recommending chlamydia retesting three months after treatment, retesting rates are low. We are conducting the first randomised controlled trial to assess the effectiveness of home collection combined with short message service (SMS) reminders on chlamydia retesting and reinfection rates in three risk groups. The REACT (retest after Chlamydia trachomatis) trial involves 600 patients diagnosed with chlamydia: 200 MSM, 200 women and 200 heterosexual men recruited from two Australian sexual health clinics where SMS reminders for retesting are routine practice. Participants will be randomised to the home group (3-month SMS reminder and home-collection) or the clinic group (3-month SMS reminder to return to the clinic). Participants in the home group will be given the choice of attending the clinic if they prefer. The mailed home-collection kit includes a self-collected vaginal swab (women), UriSWAB (Copan) for urine collection (heterosexual men), and UriSWAB plus rectal swab (MSM). The primary outcome is the retest rate at 1-4 months after a chlamydia diagnosis, and the secondary outcomes are: the repeat positive test rate; the reinfection rate; the acceptability of home testing with SMS reminders; and the cost effectiveness of home testing. Sexual behaviour data collected via an online survey at 4-5 months, and genotyping of repeat infections, will be used to discriminate reinfections from treatment failures. The trial will be conducted over two years. An intention to treat analysis will be conducted. This study will provide evidence about the effectiveness of home-collection combined with SMS reminders on chlamydia retesting, repeat infection and reinfection rates in three risk groups. The trial will determine client acceptability and cost effectiveness of this strategy. Australian and New

  5. Acute oral toxicity test and phytochemistry of some West African medicinal plants.

    Science.gov (United States)

    Awobajo, F O; Omorodion-Osagie, E; Olatunji-Bello, I I; Adegoke, O A; Adeleke, T I

    2009-01-01

    Although there is increased acceptance and utilization of medicinal plants worldwide, many are used indiscriminately without recourse to any safety test. Thus, the need for toxicity tests to determine the safe dose for oral consumption. LD50 and phytochemistry of four medicinal plants of West Africa were investigated. Thirty male and non pregnant female Swiss albino mice weighing 20grams each were used for this study. They were divided into the Control (C), Oldenlandia corymbosa L. aqueous leaf-extract treated (OCG), Parquetina nigrescens aqueous leaf extract treated (PNG), Hybanthus enneaspermus aqueous leaf extract treated (HEG), Ficus carica leaf extract treated (FCG) and Sesamum indicum aqueous seeds extract treated group (SIG). Each group except the control was further divided into four sub-groups of six mice each, and were administered orally, graded doses (SI; 1, 2, 4 and 8, PN; 2.5, 5, 10 and 20, OC; 5, 10, 20 and 40, FC; 1, 2, 4 and 8, HE; 4, 8, 16, 32) of the aqueous extract of each plant (g/kg body weight) after 12 hours fasting. The dry aqueous leaf extracts of HE, OC, PN, FC all have dark brown colour and pH ranging from 6.1 to 7.2 while the seed extract of SI has a light brown color with pH of 7.0. Flavonoids, cardiac glycosides, anthocyanosides, saponin, and reducing sugar were present in all extracts, while cyanogenic glycoside was present only in HE. LD50 determination results obtained using Thompson and Finney methods were as follows; OC; 14.14 +/- 0.27 and 10.56 +/- 0.20, PN; 12.60 +/- 0.10 and 13.10 +/- 0.10, HE; 8.14 +/- 0.30 and 8.24 +/- 0.35, FC; 3.36 +/- 0.26 and 4.00 +/- 0.04, SI; 4.00 +/- 0.10 and 3.10 +/- 0.22 respectively (LD50 values are in g/kg body weight. The results of this study have provided an oral LD50 from where a safe dose can be chosen for further research into the merits of the consumption of these medicinal plants.

  6. Review of titanium dioxide nanoparticle phototoxicity: Developing a phototoxicity ratio to correct the endpoint values of toxicity tests

    Science.gov (United States)

    2015-01-01

    Abstract Titanium dioxide nanoparticles are photoactive and produce reactive oxygen species under natural sunlight. Reactive oxygen species can be detrimental to many organisms, causing oxidative damage, cell injury, and death. Most studies investigating TiO2 nanoparticle toxicity did not consider photoactivation and performed tests either in dark conditions or under artificial lighting that did not simulate natural irradiation. The present study summarizes the literature and derives a phototoxicity ratio between the results of nano‐titanium dioxide (nano‐TiO2) experiments conducted in the absence of sunlight and those conducted under solar or simulated solar radiation (SSR) for aquatic species. Therefore, the phototoxicity ratio can be used to correct endpoints of the toxicity tests with nano‐TiO2 that were performed in absence of sunlight. Such corrections also may be important for regulators and risk assessors when reviewing previously published data. A significant difference was observed between the phototoxicity ratios of 2 distinct groups: aquatic species belonging to order Cladocera, and all other aquatic species. Order Cladocera appeared very sensitive and prone to nano‐TiO2 phototoxicity. On average nano‐TiO2 was 20 times more toxic to non‐Cladocera and 1867 times more toxic to Cladocera (median values 3.3 and 24.7, respectively) after illumination. Both median value and 75% quartile of the phototoxicity ratio are chosen as the most practical values for the correction of endpoints of nano‐TiO2 toxicity tests that were performed in dark conditions, or in the absence of sunlight. Environ Toxicol Chem 2015;34:1070–1077. © 2015 The Author. Published by SETAC. PMID:25640001

  7. Comparative toxicity test of water-accommodated fractions of oils and oil dispersants to marine organisms

    International Nuclear Information System (INIS)

    1989-01-01

    This reference method describes a simple procedure for comparing the toxicity of oil, oil dispersants, and mixtures thereof, to marine animals. It allows the toxicity of different dispersants to be rapidly compared to that of oil, or of a mixtur