Academic literature on the topic 'Individual toxicity'
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Journal articles on the topic "Individual toxicity"
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Grandjean, P. "Individual susceptibility to toxicity." Toxicology Letters 64-65 (December 1992): 43–51. http://dx.doi.org/10.1016/0378-4274(92)90171-f.
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Piatkov, Irina, Colin Rochester, Trudi Jones, and Steven Boyages. "Warfarin Toxicity and Individual Variability—Clinical Case." Toxins 2, no. 11 (October 28, 2010): 2584–92. http://dx.doi.org/10.3390/toxins2112584.
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Jones, David, Alan G. Scarlett, Charles E. West, and Steven J. Rowland. "Toxicity of Individual Naphthenic Acids toVibrio fischeri." Environmental Science & Technology 45, no. 22 (November 15, 2011): 9776–82. http://dx.doi.org/10.1021/es201948j.
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Smiley-Walters, Sarah A., Terence M. Farrell, and H. Lisle Gibbs. "High levels of functional divergence in toxicity towards prey among the venoms of individual pigmy rattlesnakes." Biology Letters 15, no. 2 (February 2019): 20180876. http://dx.doi.org/10.1098/rsbl.2018.0876.
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Venom is a complex molecular phenotype that shows high levels of variation in expressed proteins between individuals within and between populations. However, the functional significance of this variation in terms of toxicity towards prey is largely unknown. Here, we assessed the relative toxicity of venom from individual pygmy rattlesnakes ( Sistrurus miliarius ) on brown anoles ( Anolis sagrei ) using a novel assay involving tests of fixed doses of venom from individual snakes on individual lizards. We found high levels of functional variation between individual venoms within populations with individual differences (nested within population) explaining 3.6 times more variation in toxicity than population differences. Our results suggest a previously unappreciated adaptive significance to within-population variation in venom. They argue that selective mechanisms that maintain variation within populations may be of equal or greater importance to divergent selection leading to local adaption between populations as evolutionary explanations of venom variation within species.
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Schmiegelow, Kjeld. "Advances in individual prediction of methotrexate toxicity: a review." British Journal of Haematology 146, no. 5 (September 2009): 489–503. http://dx.doi.org/10.1111/j.1365-2141.2009.07765.x.
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Pai, Prathamesh S. "Treatment Intensification in the ‘High-risk’ Individual." International Journal of Head and Neck Surgery 1, no. 2 (2010): 93–96. http://dx.doi.org/10.5005/jp-journals-10001-1016.
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Abstract The high-risk individual merits treatment intensification. However, there are concerns with CERT. More supportive care is necessary as toxicity is higher. Treatment related death is a reality. Hence before we set out to prescribe concurrent chemoradiation we would need to stratify them according to the risk factors, their performance status and bear in mind the costs involved in intensive support during treatment. Apart from chemoradiation we need to explore emerging treatment strategies such as fractionated radiation therapy, and targeted therapies such as epidermal growth factor receptor blockade which might offer better if not similar results but with lesser toxicity.
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Syvak, L. A., S. A. Lyalkin, T. Ye Tarasenko, N. V. Kasap, M. Y. Klimanov, N. N. Maydanevich, A. V. Askolsky, and N. O. Verovkina. "PREDICTION OF INDIVIDUAL SENSITIVITY FOR CHEMOTHERAPY." Likarska sprava, no. 7-8 (December 30, 2018): 61–66. http://dx.doi.org/10.31640/jvd.7-8.2018(10).
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The study of individual sensitivity to chemotherapy drugs is aimed at providing treatment with the most effective schemes that will not only prolong the life of patients with cancer, but also improve its quality and eliminate unwanted toxicity.
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Syvak, L. A., S. A. Lyalkin, T. Ye Tarasenko, N. V. Kasap, M. Y. Klimanov, N. N. Maydanevich, A. V. Askolsky, and N. O. Verovkina. "PREDICTION OF INDIVIDUAL SENSITIVITY FOR CHEMOTHERAPY." Likarska sprava, no. 7-8 (December 30, 2018): 61–66. http://dx.doi.org/10.31640/vd.7-8.2018(10).
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The study of individual sensitivity to chemotherapy drugs is aimed at providing treatment with the most effective schemes that will not only prolong the life of patients with cancer, but also improve its quality and eliminate unwanted toxicity.
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Stogner, Steven W., and D. Keith Payne. "Oxygen Toxicity." Annals of Pharmacotherapy 26, no. 12 (December 1992): 1554–62. http://dx.doi.org/10.1177/106002809202601214.
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OBJECTIVE: The objective of this article is to provide an overview of the biochemistry of oxygen metabolism, including the formation of free radicals and the role of endogenous antioxidants. Pathophysiologic correlates underlying the clinical manifestations of oxygen toxicity are reviewed and management strategies are outlined. DATA SOURCES: References from basic science and clinical journals were selected from the authors' files and from a search of a computerized database of the biomedical literature. STUDY SELECTION: Articles selected for review included both historical and current literature concerning the biochemistry and pathophysiology of oxygen toxicity in animals and humans. DATA SYNTHESIS: The benefits of oxygen therapy have been known for many years; however, its potential toxicity has not been recognized until the last two decades. The lungs, the eyes, and, under certain conditions, the central nervous system are the organs most affected by prolonged exposure to hyperoxic environments. Free radical formation during cellular metabolism under hyperoxic conditions is recognized as the biochemical basis of oxygen injury to cells and organs. Endogenous antioxidants are a primary means of detoxifying reactive oxygen species and preventing hyperoxia-induced cellular damage. When this defense fails or is overwhelmed by the excessive production of hyperoxia-induced free-radical species, distinctive morphologic changes occur at the cellular level. The amount of hyperoxia required to cause cellular damage and the time course of these changes vary from species to species and from individual to individual within the same species. Age, nutritional status, presence of underlying diseases, and certain drugs may influence the development of oxygen toxicity. CONCLUSIONS: There is currently no reliably effective drug for preventing or delaying the development of oxygen toxicity in humans. Use of the lowest effective oxygen concentration, the avoidance of certain drugs, and attention to nutritional and metabolic factors remain the best means currently available to avoid or minimize oxygen toxicity. Research is continuing into more effective ways to prevent, diagnose, and treat this disorder.
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Griffiths, Stephen John. "Implications of individual particulate matter component toxicity for population exposure." Air Quality, Atmosphere & Health 4, no. 3-4 (June 16, 2010): 189–97. http://dx.doi.org/10.1007/s11869-010-0077-4.
Full textDissertations / Theses on the topic "Individual toxicity"
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Barnett, Gillian Ceri. "Individual variation in late toxicity from radiotherapy." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610065.
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Furuhagen, Sara. "Application and interpretation of biomarkers in ecotoxicology - from molecular to individual level responses." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-120161.
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The use of biomarkers is considered a promising alternative, or complement, to traditional ecotoxicological assays. Toxic effects are often initially manifested at the molecular or biochemical level, biomarkers are therefore used as sensitive indicators of toxic exposure. Ideally, biomarkers would also indicate reduced fitness and possible later effects at the individual or population levels. However, implementing biomarkers in ecotoxicology is challenging and few biomarkers have an established connection to reduced individual fitness. The aim of this thesis was to increase the value and improve the interpretation of biomarker responses in ecotoxicological studies by examining the impact of confounding factors and the relationship between oxidative biomarkers and reproductive effects in crustaceans. The sensitivity of biomarkers was confirmed in paper I as toxic effects of pharmaceuticals with conserved drug target orthologs were observed at the molecular and biochemical levels both earlier and at lower concentrations than effects on mortality and reproduction. No toxic effects were observed for the pharmaceutical without identified drug target orthologs, thus stressing the importance of considering toxic mechanisms and being aware of the most likely target when evaluating toxic effects also in non-target species. Many xenobiotics and environmental stressors interfere with oxidative processes, making oxidative biomarkers interesting to study in ecotoxicology and stress ecology. Still, feeding rate was identified as a confounding factor for antioxidant capacity (assayed as oxygen radical absorbance capacity, ORAC) and lipid peroxidation in ecotoxicological studies (paper II). However, ORAC normalized to protein was independent of altered feeding rates, hence it can be applied as a suitable exposure biomarker without considering alterations and effects of feeding rate. The connection between reproduction and oxidative stress is dual, as reproduction both can be inhibited by oxidative stress and induce pro-oxidative processes. Further, a positive association was found between ORAC and the occurrence of embryo aberrations in the benthic amphipod Monoporeia affinis (paper III). An association between antioxidant defense and reproduction was also observed for Daphnia magna (paper IV). Threshold values for identification of exposed individuals and prediction of possible later reproductive effects were established for ORAC. This thesis has contributed to diminishing some of the knowledge gaps limiting the use of oxidative biomarkers in ecotoxicology, by contributing to increased understanding of how oxidative biomarkers relate to important life-traits. Moreover, ORAC has been identified as a suitable biomarker of not only exposure, but also reproductive effects. Future research should continue to establish connections between biomarker responses and effects at higher levels, and focus on providing defined threshold values to enable predictions about later effects.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.
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Luo, Su. "Individual and combined toxicity of a mycotoxin, the deoxynivalenol and a trace metal, the cadmium on the intestine." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0072.
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Le déoxynivalénol (DON) est une mycotoxine de type trichothécène de type B, principalement produite par le genre Fusarium. C'est l'une des mycotoxines les plus répandues, elle est largement trouvée dans les céréales et les produits dérivés des céréales. Le cadmium est un composant de la croûte terrestre et un polluant environnemental courant. C'est un métal trace non essentiel et toxique pour la santé des humains et des animaux. Bien que la toxicité individuelle du DON et du Cd ait été bien étudiée, leur effet combiné est peu étudié. L'intestin étant le premier organe ciblé par les contaminants alimentaires, le but de cette étude est d'explorer l'effet combiné du DON et du Cd sur la fonction de barrière intestinale à l'aide de modèles in vitro, in vivo et ex vivo. In vitro, des cellules épithéliales intestinales humaines Caco-2 ont été traitées avec une série de concentrations de DON et de Cd (0-30 μM) seules ou en combinaison. La fonction de barrière des cellules Caco-2 a été évaluée par la mesure de la résistance électrique transépithéliale (TEER), de la perméabilité paracellulaire et des protéines jonctionnelles. Le mélange DON, Cd et DON+Cd a diminué le TEER et augmenté la perméabilité paracellulaire de manière dépendante de la concentration. L'abondance des protéines jonctionnelles E-cadhérine et occludine a été considérablement réduite dans les cellules exposées au DON, au Cd et au DON+Cd, tandis que l'expression de ZO-1 et de claudine-3 et -4 est restée inchangée. Le mélange DON Cd a eu des effets légèrement supérieurs ou similaires à ceux du contaminant le plus toxique. In vivo, les rats ont été exposés à des aliments contaminés par du DON (8,2 mg / kg), et à de l'eau de boisson contaminée par du Cd (5 mg / L) ou au mélange DON+Cd pendant 4 semaines. Les résultats n'ont montré aucun effet sur la prise de poids corporel au cours de l'expérience. Des dommages morphologiques légers caractérisés par un oedème au niveau de la lamina propria et un aplatissement et une fusion des villosités ont été découverts chez le rat exposé à chaque contaminant. Le score lésionnel du jéjunum était plus élevé chez tous les animaux traités que chez les animaux témoins. Une diminution significative de la profondeur de la crypte jéjunale a été observée chez les rats exposés au DON, au Cd et au DON+Cd, alors que la hauteur des villosités n'était pas affectée. Une immunomarquage plus faible de l'E-cadhérine dans le jéjunum de rats exposés à des contaminants seuls ou en association a également été observée, alors que l'occludine n'a diminué que chez les rats exposés au DON et au DON+Cd. Comme indiqué in vitro, l'exposition in vivo au DON et au Cd a induit des effets similaires à ceux du contaminant le plus toxique. Des explants jéjunaux de porcs ex vivo ont été exposés au DON (0-24 μM), au Cd (0-96 μM) et à la combinaison de DON+Cd. Le DON seul et le mélange DON Cd ont stimulé la réponse immunitaire chez le jéjunum en régulant positivement l'expression d'ARNm de IL-1, IL-1, IL-8 et TNF- de manière dose-dépendante, tandis que le Cd seul n'a pas affecté ces gènes. L'expression génique des métallothionéines (MT), y compris MT1A et MT2A, était régulée positivement de manière dose-dépendante par le Cd seul et le mélange, mais n'était pas affectée par le DON seul. La régulation à la hausse des gènes de cytokines et de MT induite par le DON+Cd était similaire à celle obtenue par le DON ou le Cd seul. En conclusion, le DON et le Cd modifient tous deux la fonction de barrière intestinale et l'effet combiné est similaire avec leur effet individuel. L'effet du mélange n'a démontré aucune synergie, ce qui suggère que la réglementation sur chaque contaminant protège suffisamment les consommateurs exposés aux mélanges de DON et de CdDeoxynivalenol (DON) is a type B trichothecene mycotoxin mainly produced by Fusarium genus. It is one of the most prevalent mycotoxins widely found in cereals and cereal-derived products. Cadmium is a component of earth’s crust and also a common environmental pollutant. It is a nonessential trace metal and toxic for humans and animals health. Although the individual toxicity of DON and Cd has been well investigated, their combined effect is poorly studied. As intestine is the first organ targeted by food contaminants, the aim of this study is to explore the combined effect of DON and Cd on the intestinal barrier function using in vitro, in vivo and ex vivo models. In vitro, the human intestinal epithelail cells Caco-2 were treated with a series of concentrations of DON and Cd (0-30 μM) alone or in combination. The barrier function of Caco-2 cells was assessed through the measurement of transepithelial electrical resistance (TEER), paracellular permeability and junctional proteins. DON, Cd and DON+Cd mixture decreased the TEER and increased the paracellular permeability in a concentration-dependent manner. The abundance of junctional proteins E-cadherin and occludin was considerably reduced in cells exposed to DON, Cd and DON+Cd, while the expression of ZO-1, and claudin-3 and -4 remained unchanged. The mixture DON+Cd induced slightly higher or similar effects than the most toxic contaminant. In vivo, rats were exposed to DON-contaminated feed (8.2 mg/kg feed), and Cd-contaminated drinking water (5 mg/L) or to the mixture DON+Cd for 4 weeks. The results showed no effect on body weight gain during the experiment. Mild morphological damage characterized by edema in lamina propria and villi flattening and fusion was found in rat exposed to each contaminant. The lesional score of jejunum was higher in all the treated animals than that in control animals. A significant decrease of jejunal crypt depth was observed in rats exposed to DON, Cd and DON+Cd, whereas villi height remained unaffected. A lower immunostaining of E-cadherin in the jejunum of rats exposed to contaminants alone or in combination was also observed, whereas occludin was only decreased in rats exposed to DON and DON+Cd. As shown in vitro, in vivo exposure to both DON and Cd induced similar effects than the most toxic contaminant. Ex vivo, jejunal explants of pigs were exposed to DON (0-24 μM), Cd (0-96 μM) and in combination DON+Cd. DON alone and mixture DON+Cd stimulated immune response in jejunum by upregulating mRNA expression of IL-1, IL-1, IL- 8 and TNF- in a dose-dependent manner, while Cd alone did not affect these genes. Gene expression of metallothioneins (MTs) including MT1A and MT2A was dose-dependently upregulated by Cd alone and mixture, but not affected by DON alone. The upregulation of cytokine and MTs genes induced by DON+Cd was similar than by DON or Cd alone. In conclusion, both DON and Cd alter intestinal barrier function and the combined effect is similar with their individual effect. The effect of the mixture did not demonstrate any synergy, suggesting that regulation on individual contaminant is protective enough for consumers exposed to DON and Cd mixtures
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Vogin, Guillaume. "Amélioration de la tolérance de la radiothérapie par une approche individuelle radiobiologique et une démarche conceptuelle unifiée en hadronthérapie." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10218/document.
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5 à 15% des 175 000 patients traités par radiothérapie (RT) chaque année sont exposés à une toxicité considérée comme « inhabituelle » pouvant entraîner des séquelles parfois graves. Les techniques innovantes de photonthérapie apportent une solution balistique pertinente mais inappropriée pour certaines tumeurs ou certains patients. Deux approches permettent d'entrevoir des solutions à ces situations. 1- Contribution au développement de l'hadronthérapie par ions carbone : Ces particules possèdent une masse et une charge qui leur confèrent un avantage balistique et biologique particulièrement intéressant. Le caractère rare des tumeurs éligibles et le très faible nombre de centres n'ont pas permis, ou justifié, à ce jour la réalisation d'études comparatives randomisées afin d'en évaluer le service rendu. Via le projet FP7 ULICE, nous avons intégré et animé plusieurs groupes à l'échelle nationale et internationale. Nous avons directement produit des procédures unifiées en terme d'immobilisation, de recueil des données élémentaires, de structuration protocolaire et de transformation des données en métadonnées échangeables. Nous avons proposé des concepts originaux permettant de décrire la dose prescrite et les volumes d'intérêt, au-delà du concept réducteur d'EBR. 2- Un nouveau biomarqueur de radiosensibilité individuelle (RSI). L'identification des patients les plus à risque de développer les réactions les plus sévères reste un enjeu majeur. Aucun test de RSI ne s'impose comme gold standard. A partir de primocultures fibroblastiques issues de patients ayant présenté un profil de toxicité inhabituel à la RT, le taux de cassures double brins résiduelles à 24h estimé par immunofluorescence indirecte (marqueur γH2AX) a permis de définir 3 groupes de RSI. Toutefois ce seul marqueur n'est pas assez robuste. Le délai de transit cyto-nucléaire de la protéine ATM semble affiner notre classification. Un nouveau modèle mécanistique a ainsi pu être développé5 to 15% of the 175,000 patients treated with radiation therapy (RT) annually are exposed to toxicity considered "unusual" that can lead to serious sequelae. Innovative photon RT techniques provide relevant but inappropriate ballistic solution for certain tumors or certain patients. Two approaches guide solutions to these situations.1- Contribution to the development of carbon ion RT. These particles possess a mass and a charge that give them particularly interesting ballistics and biological properties. The rarity of eligible tumors and the low care offer have failed conducting randomized controlled trials to evaluate its cost-effectiveness. Throughout the FP7-ULICE project, we directly produced standard operating procedures in terms of basic data collection, protocol structuring and processing of metadata. We proposed original concepts to describe and report the dose and volume of interest, beyond the restricted concept of RBE. 2- A novel biomarker of individual radiosensitivity (IRS). The identification of the patients the most at risk of developing the most severe reactions remains a major challenge. There is no gold standard in the field of IRS assays.From fibroblasts primocultures sampled from patients with an unusual toxicity, the number of residual DNA double-stand breaks 24h after radiation and estimated by indirect immunofluorescence (marker γH2AX) allows to identify three groups of IRS. However this single marker is not robust enough. The delay of ATM nucleoshuttling appears to refine our classification. A new mechanistic model has been developed
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Lundström, Belleza Elin. "Population modeling using harpacticoid copepods : Bridging the gap between individual-level effects and protection goals of environmental risk assessment." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-102541.
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To protect the environment from contaminants, environmental risk assessment (ERA) evaluates the risk of adverse effects to populations, communities and ecosystems. Environmental management decisions rely on ERAs, which commonly are based on a few endpoints at the individual organism level. To bridge the gap between what is measured and what is intended for protection, individual-level effects can be integrated in population models, and translated to the population level. The general aim of this doctoral thesis was to extrapolate individual-level effects of harpacticoid copepods to the population level by developing and using population models. Matrix models and individual based models were developed and applied to life-history data of Nitocra spinipes and Amphiascus tenuiremis, and demographic equations were used to calculate population-level effects in low- and high-density populations. As a basis for the population models, individual-level processes were studied. Development was found to be more sensitive compared to reproduction in standard ecotoxicity tests measuring life-history data. Additional experimental animals would improve statistical power for reproductive endpoints, but at high labor and cost. Therefore, a new test-design was developed in this thesis. Exposing animals in groups included a higher number of animals without increased workload. The number of reproducing females was increased, and the statistical power of reproduction was improved. Individual-level effects were more or equally sensitive compared to population-level effects, and individual-level effects were translated to the population level to various degrees by population models of different complexities. More complex models showed stronger effects at the population level compared to the simpler models. Density dependence affected N. spinipes populations negatively so that toxicant effects were stronger at higher population densities. The tools presented here can be used to assess the toxicity of environmental contaminants at the individual and population level, improve ERA, and thereby the basis for environmental management.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.
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Hidalgo, Nicho Eduardo Alejandro. "Toxicidad de la mezcla binaria de los plaguicidas metomilo y rotenona en la “lenteja de agua” Lemna minor (Linnaeus, 1758)." Bachelor's thesis, Universidad Ricardo Palma, 2015. http://cybertesis.urp.edu.pe/handle/urp/698.
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Se evaluó la toxicidad individual y binaria de los plaguicidas metomilo y rotenona en la macrofita Lemna minor (Linnaeus, 1753) para determinar la acción sinérgica o antagónica de una mezcla equitóxica. Los ensayos se realizaron bajo condiciones de laboratorio (T 29 ± 2°C; H 48,6 ± 9,4 %) y los resultados fueron analizados con los programas estadísticos BMDS® y Probit para calcular la concentración efectiva media (CE50) a través de los parámetros Área de la Fronda (AF) y Nuevas Frondas (NF). Los resultados sugieren una mayor precisión al utilizar el Método del Punto de Referencia del programa BMDS® para el cálculo de la concentración efectiva. Adicionalmente, se calculó la concentración total de clorofila (CTC) y peso húmedo (PH) para determinar la inhibición del crecimiento (Ir). Del mismo modo, se realizó una comparación entre los valores NOAEL (nivel de efecto no observado) y LOAEL (nivel bajo de efecto observado) versus los valores de BMDL (límite inferior del punto de referencia) y BMD (nivel de variación en el punto de referencia), respectivamente. El análisis muestra que existe una mayor precisión al emplear los valores BMD y BMDL. La acción fitotóxica varió según el parámetro analizado. La CE50 mostró mayores valores en el parámetro NF (1079,22 mg·L-1 para rotenona; 7147,42 mg·L-1 para metomilo; 597,904 mg·L-1 mezcla binaria: metomilo y 298,93 mg·L-1 mezcla binaria: rotenona) que en el parámetro AF (782,173 mg·L-1 para rotenona; 6919,79 mg·L-1 para metomilo; 629,513 mg·L-1 mezcla binaria: metomilo y 314,754 mg·L-1 mezcla binaria: rotenona). Finalmente, el modelo de concentración-adición mostró que la acción fitotóxica de la mezcla de ambos plaguicidas en Lemna minor tiene un efecto sinérgico.
Macrophyte Lemna minor (Linnaeus, 1753) was used to evaluate the phytotoxicity of the individual and mix action of methomyl and rotenone pesticides under laboratory conditions (Temperature 29 ± 2°C; Humidity 48,6 9,4 %). The taken measures to establish half effective concentration (EC50) were the frond area (AF) and production of new fronds (NF). In this study, BMDS® and Probit stadistical data analyses were used to compare the results about effective concentration. Results suggest Benchmark dose method of BMDS® program was more effective than Probit program when EC50 were determined. Additionally, total chlorophyll concentration (CTC) and humidity weight (PH) parameters were calculated to determinate the growth inhibition (Ir). Likewise, NOAEL (no observed adverse effect level) and LOAEL (low observer adverse effect level) were compared with BMDL (lower bench mark dose) and BMD (Bench mark dose), respectively. BMD and BMDL values were more accurate than NOAEL and LOAEL values. Phytotoxic action varied according the parameter. EC50 values of Lemna minor showed poor sensibility to methomyl pesticide with an elevated concentration in both parameters (6919,79 mg•L-1 and 7147,42 mg•L-1 for AF and NF, respectively). Results of rotenone pesticide were lower than methomyl, with 1079,22 mg•L-1 (NF) and 782,173 mg•L-1 (AF). Finally, the mix toxicity was 597,904 mg•L-1 (methomyl: NF), 298,93 mg•L-1 (rotenone: NF), 629,513 mg•L-1 (methomyl: AF) and 314,754 mg•L-1 (rotenone: AF). For synergy calculation, Concentration-Adition value was used, concluding a higher synergism.
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Gilbert, Alexandra Jane. "Optimising individual treatment regimes and patient outcomes through the use of patient-reported toxicity assessments in patients treated with pelvic radiotherapy." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/13268/.
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The primary objectives of this thesis are to develop a systematic method for patients to self-report pelvic radiotherapy adverse events (AE) using electronically collected patient reported outcomes (PROs) in clinical practice and to evaluate patient-reported toxicity in association with radiotherapy dosimetric data and clinical factors. Before testing the research objectives in two observational studies, important practical and methodological issues were addressed. Analysis from systematic and literature reviews, content analysis of three validated PRO systems and interviews with health professionals found the European-Organisation-for-Research-and-Treatment-of-Cancer-Quality-of-Life-Questionnaires (EORTC-QLQ) C30 and cancer-specific modules to have the most effective coverage of acute and late AE for patient treated with radiotherapy for anal, rectal, endometrial and cervical cancer. Qualitative analysis of patient cognitive interviews found the EORTC-QLQ system was acceptable to patients and revealed discrepancies in toxicity grading between patient and clinician (using the Common-Terminology-Criteria-of-Adverse-Events (CTCAE)) might be due to inherent differences in the grading descriptions between the scoring systems. Electronic methods for collection and presentation of PRO data were developed alongside technology to improve clinical data capture from electronic health records (EHR). A pilot study of 31 patients proved it was feasible to collect electronic and paper PRO data and integrate results into individual EHRs. A protocol for organ at risk (OAR) contouring and methods used for dose-volume-histogram (DVH) export were developed. The cross sectional (n=315) and prospective studies (n=129) found bowel urgency and sexual dysfunction to be the late AE most commonly reported by patients. The cross sectional study piloted the application of principal component analysis to describe DVH data from patients treated with multiple radiation techniques and demonstrated associations between PRO late toxicity and dosimetric and clinical data. The prospective study interim analysis found resolution of many treatment-related symptoms by six-months and provided encouraging findings for the use of longitudinal PRO collection in routine practice.
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Dréan, Gaël. "Mise en correspondance inter-individus pour la prédiction de la toxicité en radiothérapie du cancer de la prostate." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S041/document.
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Ces travaux de thèse s’inscrivent dans le contexte de la prédiction de la toxicité en radiothérapie du cancer de la prostate. Dans l'objectif d'analyser les corrélations spatiales entre la dose et les effets secondaires cette problématique est abordée dans un cadre d'analyse de population. La mise en correspondance inter-individus de l'anatomie et de la distribution de dose planifiée soulève des difficultés liées aux fortes variabilités anatomiques et au faible contraste des images CT considérées. Nous avons envisagé différentes stratégies de recalage non-rigide exploitant les informations relatives aux structures anatomiques, aux combinaisons intensité-structure, ou aux relations inter-structures. Les méthodes proposées s'appuient notamment sur l’utilisation de descripteurs structurels des organes tels que les cartes de distances euclidiennes ou du champ scalaire solution de l’équation de Laplace. Ces méthodes ont permis d'améliorer significativement la précision de la mise en correspondance, tant au niveau anatomique que dosimétrique. Les plus performantes ont été utilisées pour analyser une population de 118 individus. Les comparaisons statistiques des distributions de dose entre les patients souffrant ou non de saignements rectaux ont permis d’identifier une sous-région du rectum où la dose semble corrélée à la toxicité. La sous-région rectale identifiée apparaît potentiellement impliquée et hautement prédictive du risque de saignement. L'approche proposée permet d’améliorer les performances des modèles mathématiques de prédiction de la toxicitéThis thesis deals with the issue of predicting the toxicity within the context of prostate cancer radiotherapy. With the aim of analyzing the spatial correlations between dose and side effects, this problem is addressed in a population analysis framework. Inter-individual matching of both the anatomy and planned dose distribution raises difficulties related to high anatomical variability and low contrast in the CT images. We considered different strategies for non-rigid registration involving the use of information on anatomical structures, intensity-structure combinations, or inter-structures relations. The proposed methods are primarily based on the use of structural descriptors of organs such as Euclidean distance maps or scalar field solution of the Laplace equation. These methods allowed us to significantly improve the accuracy of the matching, at both the dosimetric and the anatomical level. The most accurate matching strategy has been used for analyzing a population of. Statistical comparisons of dose distributions between patients with or without rectal bleeding have been used to identify a rectal sub-region likely correlated with toxicity. The identified rectal sub-region appears potentially involved in side effects and highly predictive of the risk of bleeding. The proposed approach makes it possible to improve the performance of mathematical models for predicting the toxicity
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Smiley-Walters, Sarah Ann. "Interactions between Pigmy Rattlesnakes (Sistrurus miliarius) and a Suite of Prey Species: A Study of Prey Behavior and Variable Venom Toxicity." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1483455551984898.
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Lacas, Benjamin. "Apport clinique des méta-analyses dans les cancers ORL localement avancés." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS054.
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La radiothérapie et la chimiothérapie sont deux des traitements recommandés pour traiter les cancers ORL localement avancés. La radiothérapie conventionnelle consiste en l’administration de 70 Grays en 35 fractions sur 7 semaines (fractionnement dit « conventionnel »). La chimiothérapie peut être administrée avant (induction), en même temps (concomitant) ou après (adjuvant) le traitement locorégional (chirurgie et/ou radiothérapie). Des essais randomisés ont étudié l’efficacité d’une modification du fractionnement et d’autres l’ajout d’une chimiothérapie à un traitement locorégional. Les méta-analyses sur données individuelles consistent à recueillir les bases de données de ces essais, les vérifier et ensuite les analyser ensemble, permettant ainsi des analyses plus poussées comme la variation de l’effet selon des caractéristiques des essais ou des patients. Cette thèse avait pour objectifs :1/ La première actualisation de la méta-analyse MARCH qui a inclus 34 essais et 11 969 patients afin de déterminer si la radiothérapie à fractionnement modifié était plus efficace que le fractionnement conventionnel sur la survie. Une analyse de la toxicité a également été réalisée. La question secondaire était de savoir si le fractionnement modifié seul était plus efficace que le fractionnement conventionnel associé à une chimiothérapie concomitante.2/ La seconde actualisation de la méta-analyse MACH-NC qui a inclus 105 essais et 19 511 patients afin d’estimer l’efficacité de l’ajout d’une chimiothérapie à un traitement locorégional. La question secondaire concernait la comparaison de l’efficacité de l’ajout d’une chimiothérapie concomitante à celui d’une chimiothérapie d’inductionRadiotherapy and chemotherapy are both recommended treatments for locally advanced head and neck cancers. During conventional radiotherapy, 70 Grays are given in 35 fractions over 7 weeks (called « conventional fractionation »). Chemotherapy may be given before (induction), at the same time (concomitant) or after (adjuvant) locoregional treatment (surgery and/or radiotherapy). Many randomized clinical trials studied the efficacy of altered fractionated radiotherapy and others studied the addition of chemotherapy to locoregional treatment. Individual patient data meta-analysis consists in the collection of the databases of the trials, the check and the analysis, together. It allows to perform advanced analyses like variation of the treatment effect over trials’ or patient’s characteristics. The objectives of the present work were:1/ The first update of the MARCH meta-analysis, which included 34 trials (from 1979 to 2010) and 11,969 patients in order to study the efficacy of altered fractionated radiotherapy compared to conventional fractionation. A toxicity analysis has also been performed. A secondary question was the efficacy of altered fractionation alone compared to conventional fractionation plus concomitant chemotherapy.2/ The second update of the MACH-NC meta-analysis, which included 105 trials (1965-2010) and 19,511 patients in order to study the efficacy of the addition of chemotherapy compared to locoregional treatment. A secondary question was the efficacy of the addition of concomitant chemotherapy compared to the addition of induction chemotherapy
Books on the topic "Individual toxicity"
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Ong, Debra. Assessment of hypersensitivity syndrome reactions to trimethoprim-sulfamethoxazole and abacavir in HIV-positive individuals using a lymphocyte toxicity assay. Ottawa: National Library of Canada, 2001.
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Bernhard, David. Cigarette Smoke Toxicity: Linking Individual Chemicals to Human Diseases. Wiley & Sons, Limited, John, 2011.
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Bernhard, David. Cigarette Smoke Toxicity: Linking Individual Chemicals to Human Diseases. Wiley & Sons, Incorporated, John, 2011.
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Cigarette Smoke Toxicity Linking Individual Chemicals To Human Diseases. Wiley-VCH Verlag GmbH, 2011.
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Individual Susceptibility to Genotoxic Agents in the Human Population. Springer, 2011.
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Serres, Frederick J. De. Individual Susceptibility to Genotoxic Agents in the Human Population. Springer, 2012.
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Frid, Christopher L. J., and Bryony A. Caswell. Toxicology. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198726289.003.0002.
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To determine whether or not a contaminant has the potential to become a pollutant, its biological effects must first be established. The scientific discipline of toxicology considers the measurement of toxins, their mechanisms and the effects they have on the environment, its inhabitants and on human health. This chapter describes how contaminants behave in marine environments, how organisms are exposed to them and how they respond at the molecular, individual, population and ecosystem levels. Marine organisms exhibit a range of different responses and detoxification mechanisms that are used as the basis of approaches for measuring toxicity. The complex interactions of pollutants in the environment, their interactions with other toxicants and the large natural variability in toxic effects between species and individuals make this challenging. However, in order to regulate the production and discharge of pollutants it is critical that the impacts on ecosystems and ecosystem services are understood.
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Scordino, David. Infectious Colitis. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199976805.003.0031.
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Infectious colitis is diarrhea with evidence of colonic inflammation by visualization (colonoscopy), history (blood or mucus in the stool), or laboratory evidence (high lactoferrin). Infectious colitis is associated with direct bacterial or indirect bacterial toxin invasion of the colonic mucosa, leading to toxicity, volume loss, hemorrhage, and colonic inflammation. The most important treatment is adequate hydration, but treatment also may include loperamide (useful in patients without fever or bloody stools) and antibiotics in individuals with evidence of colitis (although not for mild to moderate diarrhea without colitis). In any individual with diarrhea, address recent travel history, possible immunosuppression, the presence of blood or mucus in the stool, and any history of vomiting or severe abdominal pain. Therapy should be focused on maintaining adequate hydration and not missing potentially dangerous etiologies. Intravenous hydration can be used for those with moderate to severe dehydration with supplemental oral hydration solutions if discharge is possible.
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Forsyth, Duncan. Physical assessment of older patients. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199644957.003.0011.
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Mental health problems may co-exist with or be the presenting feature of other medical illness in older age. All clinicians also need to consider the potential psychological impact of ill-health and its treatments on patients and their carers. This chapter gives a geriatrician’s guide to comprehensive geriatric assessment, identifying physiological changes that occur with ageing and the potential mental health presentations of common medical conditions. The ‘geriatric giants’ of falls, immobility, incontinence, delirium and drug toxicity are put in the context of maintaining higher-order cortical functioning to enable the individual to remain upright, mobile, continent and clear in their thinking. These are considered with admissions avoidance or safe discharge planning in mind.
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Hughes, Alis, and Lesley Jones. Pathogenic Mechanisms. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199929146.003.0013.
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Huntington’s disease (HD) pathogenesis is complex. In the two decades since the gene and its mutation were discovered, there has been extensive exploration of how the expanded CAG repeat in HTT leads to neurodegeneration in HD. This chapter focuses on the mechanisms that potentially contribute to the dysfunction and death of cells in HD. These include repeat instability and RNA toxicity and the production, processing, modification, and degradation of mutant huntingtin. The effects of mutant HTT on cellular processes such as transcription, transport, neurotransmission, and protein clearance are also described. The interdependence and individual importance of these mechanisms in disease etiology remains to be clarified; however, consideration of each could be important for the development of therapeutic interventions in HD.
Book chapters on the topic "Individual toxicity"
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Engin, Ayse Basak. "Combined Toxicity of Metal Nanoparticles: Comparison of Individual and Mixture Particles Effect." In Advances in Experimental Medicine and Biology, 165–93. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-49844-3_7.
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Doi, Rikuo. "Individual Difference of Methylmercury Metabolism in Animals and Its Significance in Methylmercury Toxicity." In Advances in Mercury Toxicology, 77–98. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4757-9071-9_4.
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Murty, A. S. "Toxicity of Individual Compounds, Safe Concentrations, and Toxicity to Different age Groups." In Toxicity of Pesticides to Fish, 1–13. CRC Press, 2018. http://dx.doi.org/10.1201/9781351077378-1.
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Guerranti, Cristiana, Serena Anselmi, Francesca Provenza, Andrea Blašković, and Monia Renzi. "Action of Surfactants in Driving Ecotoxicity of Microplastic-Nano Metal Oxides Mixtures: A Case Study on Daphnia magna under Different Nutritional Conditions." In Surfactants [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99487.
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The series of experiments presented in the paper served to clarify the effects of contemporary exposure to surfactant, microplastics (polyethylene and polyvinyl chloride), and nanoparticles (TiO2 and ZnO) on the model organism Daphnia magna. Exposure was evaluated with respect to the age of the organisms (“young”, 24 hours old, and “aged” 10 days old specimens), trophic status (feeding or fasting), and the simultaneous presence of a surfactant. All the above-mentioned substances are present in the wastewater coming from various environmental sources from cosmetic products. The experiments were conducted in compliance with the OECD 202:2004 guideline, which is also a reference for ecotoxicity tests required by REACH. The results showed that surfactants enhance effects of toxicity produced by the exposure to the microplastic + nanoparticle mixtures. The influence due to factors such as nutrition (effect in fasting >> feeding conditions) and the age of individuals (effects in older >> younger animals) is essential. Concerning young individuals, exposure to PE-TiO2 is the most significant in terms of effects produced: it is very significant, especially in the presence of surfactant (both under fasting and feeding conditions). On the contrary, exposure to the PE-Zn mixture shows the minor effects. The comparison with the literature, especially as regards the possibility of interpreting the toxicity trends for the various mixtures with respect to the individual elements that compose them, leads to hypothesize additive effects still to be investigated and confirms the greatest toxicity contribution of TiO2.
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Nogueira, Verónica Inês Jesus Oliveira, Ana Gavina, Sirine Bouguerra, Tatiana Andreani, Isabel Lopes, Teresa Rocha-Santos, and Ruth Pereira. "Ecotoxicity and Toxicity of Nanomaterials with Potential for Wastewater Treatment Applications." In Materials Science and Engineering, 1182–216. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1798-6.ch046.
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Nanotechnology holds the promise of develop new processes for wastewater treatment. However, it is important to understand what the possible impacts on the environment of NMs. This study joins all the information available about the toxicity and ecotoxicity of NMs to human cell lines and to terrestrial and aquatic biota. Terrestrial species seems more protected, since effects are being recorded for concentrations higher than those that could be expected in the environment. The soil matrix is apparently trapping and filtering NMs. Further studies should focus more on indirect effects in biological communities rather than only on effects at the individual level. Aquatic biota, mainly from freshwater ecosystems, seemed to be at higher risk, since dose effect concentrations recorded were remarkable lower, at least for some NMs. The toxic effects recorded on different culture lines, also give rise to serious concerns regarding the potential effects on human health. However, few data exists about environmental concentrations to support the calculation of risks to ecosystems and humans.
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K., Udayaraja G. "Pharmacogenomics Genome Wise Association Clinical Studies." In Pharmaceutical Sciences, 14–30. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1762-7.ch002.
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Pharmacogenomics deals with drug responses in individual based on genetic variation in genome. Based on genetic variations, drugs may produce more or less therapeutic effect, and same way in side effects also. Physicians can use information about your genetic makeup to choose those drugs and drug doses to get better therapy. Optimizing drug therapy and rational dose adjustment with respect to genetic makeup will maximize drug efficacy and minimal adverse effects. This broken traditional ‘trial and error' method of ‘one drug fits all', and ‘one dose fits all' which contributing to 25–50% of drug toxicity or treatment failures. This will contribute to improve the ways in which existing drugs are used, genomic research will lead to drug development to produce new drugs that are highly effective without serious side effects. This approach to bring personalized medicine more practice and drug combinations are optimized for each individual' genetic makeup.
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Ravichandiran, Nerethika, Muneesh Kumar Barman, Sai Tejaswi Lavuri, Manjita Srivastava, Shalini Sakthivel, Meenakshi Singh, Kailash Chand, Subash C. Sonkar, and Prudhvilal Bhukya. "Precision Medicine in Cancer." In Handbook of Research on Advancements in Cancer Therapeutics, 433–66. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-6530-8.ch015.
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Cancer is the one of the deadliest diseases and takes the lives of millions of people every year across the world. Due to disease heterogeneity and multi-factorial reasons, traditional treatment such as radiation therapy, immunotherapy, or chemotherapy are effective only among a small population of the patients. Tumors can have different fundamental genetic causes and protein expressions that differ from one patient to another. This variability among individual lends itself to the field of precision and personalized medicine. Following the completion of human genome sequencing, significant progress has been observed in the characterization of human epigenome, proteome, and metabolome. Pharmacogenetics and pharmacogenomics use this sequence to study the genetic causes of individual variations in drug response and the simultaneous impact of change in genome that decide the patient's response to drug respectively. On summation, identify the subpopulation of patient and provide them tailored therapy thus increasing the effectiveness of treatment. All these evolved the field of precision or personalized medicine that plays a crucial role in cancer prevention, prognosis, diagnosis, and therapeutics. These tailored therapies are characterized by increased efficiency and reduced toxicity. Not all cancers have genetic variability; some are also influenced by polymorphism of gene encoding enzymes that play an important role in pharmacokinetics of drug. The discoveries of cancer predisposition genes allow diagnosis of a patient at risk of cancer development and let them make the decision on précised individual risk modification characteristic. The use of CYP2D6 genotyping for breast cancer, mutation in KRAS in colorectal cancer, genomic variation in EGFR in small lung cancer, melanoma are some of the examples of importance of cancer predisposition genes. In recent times, distinct molecular subtypes of cancers have been identified with requirement of different treatment for each subtype. Precision medicine shifts the trend from reaction to prevention and forestalls disease progression.
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Zia Uddin Kamal, Mohammed, and Md Yunus Miah. "Arsenic Speciation Techniques in Soil Water and Plant: An Overview." In Arsenic [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99273.
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There are more than 100 different arsenic with different characteristics in the soil-water-plant ecosystem. The identification and quantification of individual arsenic species is essential for understanding the distribution, environmental fate and behavior, metabolism and toxicity of arsenic. Due to the hazardous nature of arsenic, people have a high interest in the measurement of arsenic species. The reaction of the formation of arsenic speciation in the soil-water-plant environment is briefly studied. There is little information on methods used to quantify arsenic forms and species in contaminated soil, water and plant. The purpose of this article is to understand the available sample pretreatment, extraction, separation, detection and method validation techniques for arsenic speciation analysis of arsenic species in soil, water and plant. The performances of various sample preparation and extraction processes, as well as effective separation techniques, that contribute greatly to excellent sensitivity and selectivity in arsenic speciation when coupling with suitable detection mode, and method validity are discussed. The outlines of arsenic speciation techniques are discussed in view of the importance to the completeness and accuracy of analytical data in the soil-water-plant samples. To develop cheap, fast, sensitive, and reproducible techniques with low detection limits, still needed to confine research on arsenic speciation present in environmental matrices.
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Mosharraf Hossain Bhuiyan, Md, Fahmid Kabir, Md Serajum Manir, Md Saifur Rahaman, Md Robiul Hossain, Prosenjit Barua, Bikram Ghosh, et al. "Effect of Combination of Natural Dyes and the Blocking Layer on the Performance of DSSC." In Solar Cells [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.94760.
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Over the years, researchers have been working on replacing sensitized dye for dye sensitized solar cells (DSSC), because of its low production cost, biodegradability, and non-toxicity. However, the overall performance of natural dye-based DSSCs is low compared to the DSSCs sensitized with Ruthenium based dyes. The combination of natural dyes with an optimized choice of the extracting solvents and the proper volume ratio of mixture of the dyes, enhances inherent properties, such as absorption and adsorption of the dyes. It also allows the device to utilize photon energy more efficiently over the entire visible wavelength. As a result, DSSC sensitized with the dye mixture shows higher absorbance, and cumulative absorption properties over the whole visible region than the DSSC fabricated with individual dyes and showed higher photocurrent. Another effective way to improve cell efficiency is by using a blocking layer. The blocking layer increases the photocurrent, is mainly due to the improvement of the electron recombination at the transparent conducting oxide/electrolyte interfaces. Also, the blocking layer’s compact structure creates an effective pathway for electron transportation; thus, the device’s photocurrent increases. Additionally, a slight improvement in the open-circuit voltage and fill factor was observed, thus cell efficiency enhances significantly. By both the proper ratio of dye mixture and the blocking layer improves cell performance of DSSC and opens a new pathway for future studies.
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"Review of Pharmacologic Concepts." In Environmental Toxicology, edited by Sigmund F. Zakrzewski. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780195148114.003.0007.
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Early scientific knowledge recognized two basic types of substances: beneficial ones (such as foods and medicines), and harmful ones (those that cause sickness or death). The latter were designated as poisons. Modern science acknowledges that such a strict division is not justified. As early as the sixteenth century, Paracelsus recognized that ‘‘the right dose differentiates a poison and a remedy.’’ Many chemical substances or mixtures exert a whole spectrum of activities, ranging from beneficial to neutral to lethal. Their effect depends not only on the quantity of the substance to which an organism is exposed, but also on the species and size of the organism, its nutritional status, the method of exposure, and several related factors. Alcohol is a good example. Taken in small quantities, alcohol may be harmless and sometimes even medically recommended. However, an overdose causes intoxication and, in extreme cases, death. Similarly, vitamin A is required for the normal functioning of most higher organisms, yet an overdose of it is highly toxic. If the biological effect of a chemical is related to its dose, there must be a measurable range between concentrations that produce no effect and those that produce the maximum effect. The observation of an effect, whether beneficial or harmful, is complicated by the fact that apparently homogeneous systems are, in fact, heterogeneous. Even an inbred species will exhibit marked differences among individuals in response to chemicals. An effect produced in one individual will not necessarily be repeated in another one. Therefore, any meaningful estimation of the toxic potency of a compound will involve statistical methods of evaluation. To determine the toxicity of a compound for a biological system, an observable and well-defined end effect must be identified. Turbidity or acid production, reflecting the growth or growth inhibition of a culture, may be used as an end point in bacterial systems. In some cases, such as in the study of mutagenesis, colony count may be used. Similarly, measures of viable cells, cell protein, or colony count are useful end points in cell cultures.
Conference papers on the topic "Individual toxicity"
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Sagara, Hiroshi, Tadashi Yoshida, and Masaki Saito. "Characterization of Individual Fission Products in Terms of Their Production and Transmutation." In 10th International Conference on Nuclear Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/icone10-22753.
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In order to establish a simple and common basis which can be referred for the specific studies on the fission products (FP) transmutation and its strategies, the general characteristics of the dominant individual FPs in terms of their production and transmutation in the fast reactor have been studied with an ideal model in the present paper. The potential hazard of each nuclide in long-term utilization of nuclear energy in human society has been quantitatively evaluated. During utilization of fission energy, two short half-life FPs, 90Sr and 137Cs, almost determine the total toxicity of FP nuclides in spite of the effort of transmuting them in fast reactors. The innovative transmuters (such as High Flux Reactor, Accelerator-driven system and Fusion Neutron Source) are needed to reduce these 2 toxicities. In case of 1000-year fission energy utilization with transmutation in fast reactors, the total toxicity of FP nuclides except 126Sn go down below the level of 238U toxicity consumed. The more detailed study of transmutation of 126Sn is a very important in future. However, in the case of 10,000-year fission energy utilization with transmutation in fast reactor, total toxicities of all FP nuclides go down below the level of 238U toxicity consumed.
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Jason John Churchill. "Re-examining "Nitrate Toxicity": A Call for a More Rational Approach to Effluent Limits for Nitrogen in Decentralized Wastewater Treatment." In Eleventh Individual and Small Community Sewage Systems Conference Proceedings, 20-24 October 2007, Warwick, Rhode Island. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2007. http://dx.doi.org/10.13031/2013.23980.
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Zimmermann, Kristen A., Jianfei Zhang, Harry Dorn, Christopher Rylander, and Marissa Nichole Rylander. "Synthesis and Cytotoxicity Analysis of Carbon Nanohorn-Quantum Dot Complexes." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53968.
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Carbon nanoparticles have the potential to significantly impact the medical field over the next decade. Currently, carbon nanoparticles are being studied for a myriad of applications, including drug delivery, selective laser therapy, imaging, and biosensing. The most common type of carbon particles being investigated are carbon nanotubes (CNTs). CNTs are attractive materials for medical applications because of their physical properties and the ease with which they can be surface modified; however, there is a great deal of controversy over their possible toxicity. A more novel type of CNT that was discovered in 1999 by Iijima et al. is the carbon nanohorn [1]. Individual single-walled nanohorns (SWNHs) are single graphene sheets that roll into a conical open ended structure. The open ends of these cones are then attracted to one another through van der Waals interactions and form a flower-like final structure [2]. SWNHs are more favorable for medical applications because they are produced without the use of metal catalysts abating the concern of toxicity associated with CNTs.
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Mogi, Katsuo, Yasuhiko Sugii, Teruo Fujii, and Yoichiro Matsumoto. "A Microfluidic Culturing System for Observation of Free-Floating Microorganisms." In ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icnmm2013-73164.
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We observed the effect of the ethanol toxicity on individual cells of Botryococcus braunii (B. braunii) in microchannel environment. For continuous observation of B. braunii in microchannel environment, a microfluidic device which has a specific channel structure was developed. By using the channel structure, microorganisms were sorted by their size and captured on the corresponding area in the channel. In the experiment, suspension of B. braunii with DAPI was injected into the device for the cell capturing in the experiment. Following the cell capturing, ethanol with DAPI 0.5% was injected into the channel for 60 minutes. Damaged cells were confirmed by their deformation and the fluorescence of DAPI. The strong fluorescence of DAPI was confirmed after 20 minutes. On the other hand, the fluorescence of the chloroplast became weak in contrast to the fluorescence of DAPI. We successfully confirmed the time condition of exposing B. braunii to ethanol in the micro channel.
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Liu, Yaling, Jifu Tan, and Antony Thomas. "A Hybrid Particle-Cell Model for Nanoparticle Targeted Delivery in Microcirculation." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53033.
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Multifunctional nanomedicine holds considerable promise as the next generation of medicine that allows for targeted therapy with minimal toxicity. Most current theoretical studies considered nanoparticle (NP) suspensions in a Newtonian fluid without blood cells [1–3]. However, blood is a complex biological fluid composed of deformable cells, proteins, platelets, and plasma. For blood flow in capillary, arterioles and venules, the particulate nature of the blood need to be considered in the delivery process. Non-Newtonian effects such as the cell-free-layer and nanoparticle-cell interaction will largely influence both the dispersion and binding rates, thus impact targeted delivery efficacy. In this paper, a particle-cell hybrid model is developed to model NP transport, dispersion, and adhesion dynamics in blood suspension. The motion and deformation of red blood cell is captured through Immersed Finite Element method. The motions and adhesion of individual NPs are tracked through Brownian adhesion dynamics. A mapping and interaction potential function is introduced to consider the cell-particle collision. NP dispersion and binding coefficients are derived from the developed model under various rheology conditions. The influence of vascular flow rate, diameter, and particle size on NP distribution and delivery efficacy is characterized.
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Gernand, Jeremy M., and Elizabeth A. Casman. "Selecting Nanoparticle Properties to Mitigate Risks to Workers and the Public: A Machine Learning Modeling Framework to Compare Pulmonary Toxicity Risks of Nanomaterials." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62687.
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Due to their size and unique chemical properties, nanomaterials have the potential to interact with living organisms in novel ways, leading to a spectrum of negative consequences. Though a relatively new materials science, already nanomaterial variants in the process of becoming too numerous to be screened for toxicity individually by traditional and expensive animal testing. As with conventional pollutants, the resulting backlog of untested new materials means that interim industry and regulatory risk management measures may be mismatched to the actual risk. The ability to minimize toxicity risk from a nanomaterial during the product or system design phase would simplify the risk assessment process and contribute to increased worker and consumer safety. Some attempts to address this problem have been made, primarily analyzing data from in vitro experiments, which are of limited predictive value for the effects on whole organisms. The existing data on the toxicity of inhaled nanomaterials in animal models is sparse in comparison to the number of potential factors that may contribute to or aggravate nanomaterial toxicity, limiting the power of conventional statistical analysis to detect property/toxicity relationships. This situation is exacerbated by the fact that exhaustive chemical and physical characterization of all nanomaterial attributes in these studies is rare, due to resource or equipment constraints and dissimilar investigator priorities. This paper presents risk assessment models developed through a meta-analysis of in vivo nanomaterial rodent-inhalational toxicity studies. We apply machine learning techniques including regression trees and the related ensemble method, random forests in order to determine the relative contribution of different physical and chemical attributes on observed toxicity. These methods permit the use of data records with missing information without substituting presumed values and can reveal complex data relationships even in nonlinear contexts or conditional situations. Based on this analysis, we present a predictive risk model for the severity of inhaled nanomaterial toxicity based on a given set of nanomaterial attributes. This model reveals the anticipated change in the expected toxic response to choices of nanomaterial design (such as physical dimensions or chemical makeup). This methodology is intended to aid nanomaterial designers in identifying nanomaterial attributes that contribute to toxicity, giving them the opportunity to substitute safer variants while continuing to meet functional objectives. Findings from this analysis indicate that carbon nanotube (CNT) impurities explain at most 30% of the variance pulmonary toxicity as measured by polymorphonuclear neutrophils (PMN) count. Titanium dioxide nanoparticle size and aggregation affected the observed toxic response by less than ±10%. Difference in observed effects for a group of metal oxide nanoparticle associated with differences in Gibbs Free Energy on lactate dehydrogenase (LDH) concentrations amount to only 4% to the total variance. Other chemical descriptors of metal oxides were unimportant.
Reports on the topic "Individual toxicity"
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Moores, Lee, Alan Kennedy, Lauren May, Shinita Jordan, Anthony Bednar, Stacy Jones, David Henderson, Luke Gurtowski, and Kurt Gust. Identifying degradation products responsible for increased toxicity of UV-degraded insensitive munitions. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42020.
Full textAbstract:
Degradation of insensitive munitions (IMs) by ultraviolet (UV) light has become a concern following observations that some UV-degradation products have increased toxicity relative to parent compounds in aquatic organisms. This investigation focused on the Army's IM formulation, IMX-101, composed of three IM constituents: 2,4-dinitroanisole (DNAN), 3-nitro-1,2,4-triazol-5-one (NTO), and nitroguanidine (NQ). The IM constituents and IMX-101 were irradiated in a UV photo-reactor and then administered to Daphnia pulex in acute (48 h) exposures comparing toxicities relative to the parent materials. UV-degradation of DNAN had little effect on mortality whereas mortality for UV-degraded NTO and NQ increased by factors of 40.3 and 1240, making UV-degraded NQ the principle driver of toxicity when IMX-101 is UV-degraded. Toxicity investigations for specific products formed during UV-degradation of NQ, confirmed greater toxicity than the parent NQ for degradation products. Summation of the individual toxic units for the complete set of individually measured UV-degradation products identified for NQ only accounted for 25% of the overall toxicity measured in the exposures to the UV-degraded NQ product mixture. Given the underestimation of toxicity using the sum toxic units for the individually measured UV-degradation products of NQ, we conclude that: (1) other unidentified NQ degradation products contributed principally to toxicity and/or (2) synergistic toxicological interactions occurred among the NQ degradation product mixture that exacerbated toxicity.