Academic literature on the topic 'H+ toxicity'
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Journal articles on the topic "H+ toxicity"
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Dodd, Darol E., Gary M. Hoffman, and Colin J. Hardy. "Perfluoro-n-Butyl Iodide: Acute Toxicity, Subchronic Toxicity and Genotoxicity Evaluations." International Journal of Toxicology 23, no. 4 (July 2004): 249–58. http://dx.doi.org/10.1080/10915810490502050.
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Perfluoro-n-butyl iodide (PFBI) is a promising alternative to chlorofluorocarbon solvents used in aircraft ground maintenance operations and other military and commercial operations, because it cleans well, has zero ozone depletion potential, and has extremely low global warming properties. Toxicity tests were performed with PFBI to determine and evaluate its health hazard. Using standard testing guidelines (e.g., Organization for Economic Cooperation and Development [OECD]), tests included acute (4-h) and 4-week (6 h/day, 5 days/week) inhalation (nose-only) toxicity studies in rats, acute (10-min) inhalation cardiac sensitization study in dogs, in vitro chromosomal aberrations experiments in human lymphocytes, and in vitro mutagenic experiments in Salmonella typhimurium and Escherichia coli. There were no mortalities in rats ( n = 10) exposed for 4 h to 10,000 ppm PFBI, but all rats ( n = 10) died within 2 h when exposed to 20,000 ppm PFBI. The 4-h LC50 (95% confidence limits) was 14,000 ppm (13,000 ppm to 16,000 ppm). Signs (nasal discharge and labored breathing) observed in the rats exposed to 10,000 ppm returned to normal within 48 h. PFBI has the potential to cause cardiac sensitization in epinephrine-challenged dogs at 6200 ppm. A concentration of 3900 ppm was a no-observed-adverse-effect level (NOAEL) in the cardiac sensitization study. In the 4-week inhalation study (5 rats/sex/group), respiratory mucosal hypertrophy/hyperplasia was observed in rats of the 10,000-ppm group. A NOAEL of 1000 ppm was selected for the 4-week study on the basis that the mild increase in T4 observed at 1000 ppm was considered adaptive, not adverse, because of the absence of frank effects in the thyroid. In the in vitro studies, PFBI showed no evidence of either mutagenic or clastogenic activity. The toxicity profile of PFBI was compared to trifluoroiodomethane. In conclusion, the results of these studies indicate a low order of general toxicity and an absence of genotoxicity following PFBI exposure.
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Aidar, Elizabeth, Teresa C. S. Sigaud-Kutner, Márcia C. Bicega, Katya P. Schinke, Sania M. F. Gianesella, and Elisabete S. Braga. "Evaluation of produced water toxicity from an oil maritime terminal through Skeletonema costatum toxicity tests." Revista Brasileira de Oceanografia 47, no. 2 (1999): 137–44. http://dx.doi.org/10.1590/s1413-77391999000200003.
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The liquid effluent from an oil maritime terminal, with produced water as the main component, had its toxicity evaluated through toxicity tests with the diatom Skeletonema costatum. Two previously treated effluent samples (effluents A and B), were provided by PETROBRAS for the experiments. Both samples presented high salinity (67‰ for effluent A and 62‰ for effluent B) and low pH values (6.2), whereas total sulphide, phenol and nutrient content, dissolved/dispersed petroleum hydrocarbon concentration, BOD and COD values were quite different from each other. During the toxicity experiment, three replicate flasks with samples for each treatment were exposed to a light radiation of 266µE m² S-1 and maintained under a 10 h/14 h lightldark cycle, at a temperature of 24 :t 2ºC. The EC50 values could not be accurately estimated for effluent A: 60 h and 132 h after starting the experiment they were below 3% and between 3-6% effluent concentration, respectively. Synergistic effects between effluent toxicity and salinity on the growth of S. costatum were detected. The effluent B showed higher toxicity: the EC5O values were 0.17% and 0.40% of effluent concentrations, after 48 h and 96 h, respectively. These results evidenced the deleterious effects of residual organic compounds contained in the aqueous effluents from the oil terminal under the present pretreatment on S. costatum. In the light of the present data, the direct disposal ofthese effluents into São Sebastião Channel waters might be very hazardous to its indigenous biota.
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Cav, Spencer B., Stuart Berr, and Daniel C. Han. "Cyclosporin Toxicity in the Dog Kidney h Vido." Investigative Radiology 26, no. 12 (December 1991): 1141. http://dx.doi.org/10.1097/00004424-199112000-00103.
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Shukla, Madhulekha, and Sunita Arya. "CADMIUM TOXICITY INDUCED MORPHOLOGICAL ALTERATION IN INDIGENOUS FISH Heteropneustes fossilis (Bloch.)." Green Chemistry & Technology Letters 3, no. 1 (October 7, 2017): 21–25. http://dx.doi.org/10.18510/gctl.2017.315.
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The aim of present study was to determine the toxicity (LC50) of cadmium chloride in freshwater catfish Heteropneustes fossilis. Acute toxicity of cadmium on the indigenous fish H., fossilis was designed in the fish aquarium in laboratory at room temperature in Department of Zoology, DGPG College at Kanpur.Treated fish H., fossilis induced morphological alteration against cadmium chloride toxicity. H. fossilis showed morphological alteration such as increased opercula movement, abnormal swimming, and loss of buoyancy and fading of their body colour. Control fishes were also continuously monitored and compared with the changes caused by cadmium concentration. Heteropneustes fossilis exposed different concentration of cadmium chloride toxicity i.e. 0 ppm for 24 h, 10 ppm for 48h, 15ppm for 72h and 20 ppm for 96 h. From this present study it seems that the indigenous fish, H. fossilis is more susceptible to cadmium toxicity.
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Raipulis, Jēkabs, Malda Toma, and Maija Balode. "Toxicity and Genotoxicity Testing of Roundup." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 63, no. 1-2 (January 1, 2009): 29–32. http://dx.doi.org/10.2478/v10046-009-0009-6.
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Toxicity and Genotoxicity Testing of Roundup Glyphosate, in the commercial formulation named Roundup, is a broad spectrum herbicide that is one of the most frequently applied pesticides in the world. However, there has been little evidence of Roundup toxicity or genotoxicity. Genotoxicity of glyphosate was carried out using the Escherichia coli SOS chromotest. The glyphosate-induced dose response in the SOS chromotest suggests that glyphosate possesses genotoxic properties. Glyphosate at a 0.2 g/l concentration in toxicity bioassay caused 50% mortality of Daphnia magna (LD50 after 24 h — 0.22 g/l; after 48 h — 0.19 g/l), but 0.25 — 0.5 g/l — 100% death of organisms (LD100 after 24 h — 0.5 g/l; after 48 h — 0.25 g/l). Our results (E. coli SOS chromotest and daphnia test system) together with recent animal studies and epidemiological reports suggest that glyphosate, especially, Roundup possesses both toxic and genotoxic properties.
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Mustafa, Mohamad G. "Biochemical basis of ozone toxicity." Free Radical Biology and Medicine 9, no. 3 (January 1990): 245–65. http://dx.doi.org/10.1016/0891-5849(90)90035-h.
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McCalla, Laura B., Bryn M. Phillips, Brian S. Anderson, Jennifer P. Voorhees, Katie Siegler, Katherine R. Faulkenberry, Maurice C. Goodman, Xin Deng, and Ron S. Tjeerdema. "Effectiveness of a Constructed Wetland with Carbon Filtration in Reducing Pesticides Associated with Agricultural Runoff." Archives of Environmental Contamination and Toxicology 82, no. 3 (January 5, 2022): 317–29. http://dx.doi.org/10.1007/s00244-021-00909-0.
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AbstractThe Salinas Valley in Monterey County, California, USA, is a highly productive agricultural region. Irrigation runoff containing pesticides at concentrations toxic to aquatic organisms poses a threat to aquatic ecosystems within local watersheds. This study monitored the effectiveness of a constructed wetland treatment system with a granulated activated carbon (GAC) filter installation at reducing pesticide concentrations and associated toxicity to Ceriodaphnia dubia, Hyalella azteca, and Chironomus dilutus. The wetland was supplied with water pumped from an impaired agricultural and urban drainage. Across five monitoring trials, the integrated system’s average pesticide concentration reduction was 52%. The wetland channel and GAC filtration components individually provided significant treatment, and within each, pesticide solubility had a significant effect on changes in pesticide concentrations. The integrated treatment system also reduced nitrate by 61%, phosphate by 73%, and turbidity by 90%. Input water was significantly toxic to C. dubia and H. azteca in the first trial. Toxicity to C. dubia persisted throughout the system, whereas toxicity to H. azteca was removed by the channel, but there was residual toxicity post-GAC. The final trial had significant input toxicity to H. azteca and C. dilutus. The channel reduced toxicity to H. azteca and removed toxicity to C. dilutus. GAC filtration reduced H. azteca toxicity to an insignificant level. There was no input toxicity in the other three trials. The results demonstrate that a wetland treatment system coupled with GAC filtration can reduce pesticide concentrations, nutrients, suspended particles, and aquatic toxicity associated with agricultural runoff.
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Diaz, Lina Maria Caceres, Claudia Campos, and Gideon Oron. "Toxicity Effects of Selected Heavy Metals on Lactuca sativa and Hydra viridissima used for Sustainable Crop Production." Environmental Management and Sustainable Development 7, no. 3 (July 30, 2018): 82. http://dx.doi.org/10.5296/emsd.v7i3.13446.
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This study examines the prospects for using Hydra viridissima toxicity test 96-h LC50, served as a model invertebrate, Lactuca sativa L. was applied for seeds toxicity test (120-h IC50) and a model plant for an acute toxicity assessment of heavy metals content in water. The heavy metals used to assess the acute toxicity of the water utilized for agricultural irrigation in arid regions includes cadmium (CdCl2.2H2O), chromium (K2Cr2O7), zinc (ZnSO4. 7H2O), and boron (H3BO3). A grading of the substances was conducted, and it was found that the toxicity levels for H. viridissima and L. sativa were, with the least harmful first: B < Cr < Zn < Cd and Zn < B < Cr < Cd, respectively. Results indicate that H. viridissima was a more sensitive indicator of toxicity for all of the evaluated substances. However, L. sativa could also be used successfully to rank toxicants in order of their potential hazards.
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Curtis, Lawrence R., Wayne K. Seim, Lisbeth K. Siddens, Debra A. Meager, Richard A. Carchman, Walter H. Carter, and Gary A. Chapman. "Role of Exposure Duration in Hydrogen Ion Toxicity to Brook (Salvelinus fontinalis) and Rainbow Trout (Salmo gairdneri)." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 1 (January 1, 1989): 33–40. http://dx.doi.org/10.1139/f89-005.
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Acidification of streams and rivers associated with rainstorm or snowmelt events is often episodic as are many environmental introductions of toxic substances. We examined the toxicity of continuous or intermittent exposures to sulfuric acid (H+) to brook trout (Salvelinus fontinalis) embryos, alevins, and fry. Acute toxicity tests were conducted with juvenile rainbow trout (Salmo gairdneri). These studies permitted evaluation of key components of intermittent exposures (toxicant concentration, exposure duration, and recovery period) on mortality, reduced growth, and perturbed electrolyte balance. Lethality of H+ markedly changed with developmental stage of brook trout. Resistance of the chorion to H+ penetration probably protected embryonic fish, while hatching and onset of active swimming exacerbated H+ toxicity. Response surface methods demonstrated that between pH 4 and 7, time–concentration relationships for H+ toxicity were greatly influenced by exposure duration and peak concentration but little by length of recovery period. Daily pulses at pH 4 with duration as short 4.5 h produced marked mortality after 90 d. This did not occur after 4–60 d of testing. Whole-body Na+, K+, and Ca2+ concentrations of brook trout were negatively correlated with mean H+ concentrations after 90 d of exposure. Cation depletion appeared to be a more sensitive index of chronic, sublethal H+ toxicity than reduced growth.
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Reid, B. L., and G. W. Bennett. "Dietary Toxicity Trial, 1987." Insecticide and Acaricide Tests 14, no. 1 (January 1, 1989): 382. http://dx.doi.org/10.1093/iat/14.1.382a.
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Abstract Laboratory tests evaluated the toxicity of the dihaloalkyl arylsulfone biocide, A-9248 (diiodomethyl para-tolyl sulfone), when fed continuously to German cockroach nymphs from the second and fifth (last) nymphal stage until adulthood. The toxicants were formulated into diets prepared by finely grinding Wayne Rodent Blox into 5-g portions and reconstituting each with 6 ml of water and 3 ml of an acetone solution of technical A-9248. This was mixed thoroughly, pressed into plexiglass molds, and allowed to dry for 48 h within an evacuation hood, yielding pelletized diets (75-100 mg) of the desired concentration (% AI). Seven diet concentrations (10-0.156%; 0.5 times serial dilutions) were evaluated to achieve a clear representation of A-9248 activity. Groups of 10 unsexed, newly eclosed (<24 h) second- or fifth-stage nymphs were placed into 100- by 25-mm vented plastic Petri dishes supplied with test diet, water vial, and cardboard harborage. Each diet concentration was replicated 6 times, for a total of 60 nymphs/dilution rate.
Dissertations / Theses on the topic "H+ toxicity"
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Frantseva, Marina. "H¦2O¦2 induced toxicity in rat organotypic hippocampal cultures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0028/MQ51596.pdf.
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Islam, Mohammed Anowarul. "Responses of accessions of Austrodanthonia spp. to factors associated with soil acidity." Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/502.
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Pasture plants already adapted to acidic soil conditions are required as part of an integrated approach (with lime amelioration) to managing acid soils on the Tablelands of New South Wales, Australia. The objective of this thesis is to evaluate the usefulness of Austrodanthonia species for this purpose. The material evaluated in this study was collected during a previous survey of the distribution of Austrodanthonia on the Central, Southern and Monaro Tablelands of New South Wales. It was hypothesised that the genus Austrodanthonia has a wide range of tolerance to acid soils. A series of experiments that provided information on the growth and physiology of Austrodanthonia in relation to soil acidity, with a view to the identification and eventual domestication of the most promising plant material have been conducted through pot, hydroponics and field investigations. Firstly, soils were acidified or limed to obtain a range of soil pH and Al concentrations. This experiment showed that adding aluminium sulfate and calcium carbonate followed by washing excess salts with water is a simple, rapid and convenient method for adjusting soil pH for pot experiments. The pH of the amended soils remained relatively unchanged eight months after treatment. The experimental set-up also resulted in a wide range of soluble Al (2-52 mg/kg) across the soils. The relative Al-tolerance of 183 accessions from 15 Austrodanthonia species was tested in a pot experiment using a range of soil pH. Emergence, survival and growth of all accessions were drastically reduced by high soil acidity (pH 3.9, P < 0.001). About 11% of plants emerged at pH 3.9, whereas at pH 4.4 and 5.3, ~72% of plants emerged. Accessions exhibited large variation within and between species in their tolerance to soil acidity. From the species/accessions tested, 49 accessions from eight species were selected for further study (on the basis of being more acid tolerant). Hydroponic experiments conducted in the glasshouse evaluated: (i) formulation of nutrient solution with a stable pH, (ii) effectiveness of the formulation using tap water and deionised water and (iii) estimation of free ion activities of Al and Mn in the nutrient solution and their effects on Austrodanthonia growth. These experiments showed that a NO3-N/NH4-N ratio of 9:4 is the most appropriate ratio to obtain a stable pH 4.0 without affecting plant growth; that there was little difference between tap water and deionised water on the ionic effects of Al and Mn, and plant-size did not play a role on accession survival and that accessions of Austrodanthonia could grow well within a wide range of pH (3.5-5.5), Al (50-250 �M) and Mn (100-2000 �M). Growth of Austrodanthonia accessions declined under high acidity (pH < 3.5) and Al (300 �M), but tolerated high concentrations of Mn (2000 �M). Root-tips stained with hematoxylin grouped accessions in a similar way to the pot and hydroponic experiments for most of the accessions tested. The intensity of root staining with hematoxylin and the differential distribution of Al in the shoots and roots provided an indication that different tolerance mechanisms may be involved with Austrodanthonia accessions. It appears that both exclusion and internal mechanisms may operate for Al- and Mn-tolerance. A field experiment was conducted at Carcoar (33037�S, 149013�E, elevation 800 m) using gradients in soil pH and Al available on-site to grow selected accessions of Austrodanthonia. The accessions exhibited a range of responses to soil acidity. The accession responses to acidity from the pot and hydroponic experiments were similar to those obtained in the field, especially where Al was present as a low Al-challenge. Overall, this study shows that Austrodanthonia exhibits a wide range of acid tolerance between species and accessions within species. Among the species tested, A. duttoniana and A. fulva appeared to have the greatest commercial potential, because of their productivity and acid tolerance. The variability that exists in the accessions may be exploitable in breeding and selection programs for improved cultivars.
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Islam, Mohammed Anowarul. "Responses of accessions of Austrodanthonia spp. to factors associated with soil acidity." University of Sydney. Food and Natural Resources, 2002. http://hdl.handle.net/2123/502.
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Pasture plants already adapted to acidic soil conditions are required as part of an integrated approach (with lime amelioration) to managing acid soils on the Tablelands of New South Wales, Australia. The objective of this thesis is to evaluate the usefulness of Austrodanthonia species for this purpose. The material evaluated in this study was collected during a previous survey of the distribution of Austrodanthonia on the Central, Southern and Monaro Tablelands of New South Wales. It was hypothesised that the genus Austrodanthonia has a wide range of tolerance to acid soils. A series of experiments that provided information on the growth and physiology of Austrodanthonia in relation to soil acidity, with a view to the identification and eventual domestication of the most promising plant material have been conducted through pot, hydroponics and field investigations. Firstly, soils were acidified or limed to obtain a range of soil pH and Al concentrations. This experiment showed that adding aluminium sulfate and calcium carbonate followed by washing excess salts with water is a simple, rapid and convenient method for adjusting soil pH for pot experiments. The pH of the amended soils remained relatively unchanged eight months after treatment. The experimental set-up also resulted in a wide range of soluble Al (2-52 mg/kg) across the soils. The relative Al-tolerance of 183 accessions from 15 Austrodanthonia species was tested in a pot experiment using a range of soil pH. Emergence, survival and growth of all accessions were drastically reduced by high soil acidity (pH 3.9, P < 0.001). About 11% of plants emerged at pH 3.9, whereas at pH 4.4 and 5.3, ~72% of plants emerged. Accessions exhibited large variation within and between species in their tolerance to soil acidity. From the species/accessions tested, 49 accessions from eight species were selected for further study (on the basis of being more acid tolerant). Hydroponic experiments conducted in the glasshouse evaluated: (i) formulation of nutrient solution with a stable pH, (ii) effectiveness of the formulation using tap water and deionised water and (iii) estimation of free ion activities of Al and Mn in the nutrient solution and their effects on Austrodanthonia growth. These experiments showed that a NO3-N/NH4-N ratio of 9:4 is the most appropriate ratio to obtain a stable pH 4.0 without affecting plant growth; that there was little difference between tap water and deionised water on the ionic effects of Al and Mn, and plant-size did not play a role on accession survival and that accessions of Austrodanthonia could grow well within a wide range of pH (3.5-5.5), Al (50-250 �M) and Mn (100-2000 �M). Growth of Austrodanthonia accessions declined under high acidity (pH < 3.5) and Al (300 �M), but tolerated high concentrations of Mn (2000 �M). Root-tips stained with hematoxylin grouped accessions in a similar way to the pot and hydroponic experiments for most of the accessions tested. The intensity of root staining with hematoxylin and the differential distribution of Al in the shoots and roots provided an indication that different tolerance mechanisms may be involved with Austrodanthonia accessions. It appears that both exclusion and internal mechanisms may operate for Al- and Mn-tolerance. A field experiment was conducted at Carcoar (33037�S, 149013�E, elevation 800 m) using gradients in soil pH and Al available on-site to grow selected accessions of Austrodanthonia. The accessions exhibited a range of responses to soil acidity. The accession responses to acidity from the pot and hydroponic experiments were similar to those obtained in the field, especially where Al was present as a low Al-challenge. Overall, this study shows that Austrodanthonia exhibits a wide range of acid tolerance between species and accessions within species. Among the species tested, A. duttoniana and A. fulva appeared to have the greatest commercial potential, because of their productivity and acid tolerance. The variability that exists in the accessions may be exploitable in breeding and selection programs for improved cultivars.
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Oliveira, Andre Nazario de. "Determinação da toxidade in vitro e vivo de compostos quinazolinicos e identificação do acido homovanilico por espectrometria de ressonancia magnetica nuclear de hidrogenio (1 ANTPOT. H)." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311380.
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Orientadores: Nelci Fenalti Hoehr, Roberto RittnerDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Este projeto tem a finalidade de analisar as características toxicológicas de novos compostos quinazolínicos, que foram sintetizados recentemente no Instituto de Química-UNICAMP. Uma série de derivados de 4-fenilamino quinazolinas foi sintetizada como potentes inibidores da proteína quinase e sua citotoxicidade foi demonstrada através de técnicas de Inibição de Crescimento de 50% da população celular, onde procuramos estabelecer alguns efeitos biológicos desses novos compostos quinazolínicos, através de cultura de células PC12 e de cultura de células tumorais humanas, recomendadas pelo NCI (The U.S. National Cancer Institute) para ensaios anti-proliferiativos para estudos do câncer. A utilização da metodologia de "docking molecular" nos levou ao descobrimento do sítio de ação dos compostos quinazolínicos em células tumorais de mama (MCF07). Estudos com camundongos foram realizados, utilizando a metodologia recomendada pela OECD (Organisation for Economic Co-operation and Development), para determinação in vivo da toxicidade aguda pelos compostos quinazolínicos, descrevendo os efeitos causados pelas diferentes concentrações dos compostos quinazolínicos em estudo aplicadas aos animais. Através da Espectrometria de Ressonância Magnética Nuclear de Hidrogênio (¹H) pôde-se identificar o metabólito final das catecolaminas, o ácido homovanílico em urina, escolhido por ser um composto que aparece em grandes concentrações na urina e por ser de excelente precisão diagnóstica em algumas doenças neurológicas.
Abstract: This project aims to analyze the toxicological characteristics of new quinazoline compounds, which were summarized recently in the Institute of Chemistry-UNICAMP. The compound 4-phenylamino quinazoline was synthesized as a potent inhibitor of protein kinase and its cytotoxicity was demonstrated by an inhibitory activity on growth of human tumor cell lines. Through techniques of 50% Growth Inhibition of cell lines we provide some biological effects of these new quinazoline compounds through PC12 cell culture and culture of human tumor cells, as recommended by the NCI (The U.S. National Cancer Institute) for testing anti-proliferative for studies of cancer. The use of the methodology of "molecular docking" has led to the discovery the binding site of action of quianzoline compounds in breast tumor cells (MCF07). Studies with mice were performed, using the methodology recommended by the OECD (Organisation for Economic Co-operation and Development), to determine in vivo toxicity of the quinazoline compounds, describing the effects caused by different concentrations of quinazoline compounds under study applied to animals. Through the Nuclear Magnetic Resonance Spectrometry of Hydrogen (¹H) was able to identify the final metabolite of catecholamines, the acid in urine homovanílico, chosen to be a compound that appears in high concentrations in urine and to be an excellent diagnostic marker in some neurological diseases.
Mestrado
Ciencias Biomedicas
Mestre em Ciências Médicas
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Gaudu, Philippe. "Activation de l'oxygène moléculaire par la NAD(P)H : flavine oxydoréductase de Escherichia coli : applications à l'étude du stress oxydant." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10018.
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La majeure partie de l'oxygene consomme par les organismes aerobes est reduite en molecule d'eau au niveau de la chaine respiratoire qui produit les elements energetiques au metabolisme cellulaire. Cependant, la reduction monoelectronique de l'oxygene conduit au radical superoyde, un compose toxique. Les organismes aerobes s'en protegent en exprimant les superoxide dismutases (sod). Chez e. Coli trois enzymes ont ete caracterisees comme des sources de superoxyde. Les flavines, reduites par le nadph ou nadh, produisent cette espece en milieu aqueux. La production de superoxyde est fortement augmentee par la nad(p)h:flavine oxydoreductase, qui catalyse la reduction des flavines libres (fmn, fad, riboflavine) a partir du nadph ou du nadph. Elle peut etre utilisee comme un outil simple, efficace et selectif de production de superoxide. Des etudes de piegeage de radicaux ont ete utilisees pour etudier la formation de ces radicaux. La nadph:sulfite oxydoreductase et la nadph:ferredoxine oxydoreductase catalysent la reduction du paraquat, un herbicide, qui reduit l'oxygene moleculaire en superoxyde. La premiere enzyme est probablement responsable de la toxicite du paraquat, in vivo. La ribonucleotide reductase est une enzyme fondamentale pour les cellules. Elle catalyse la production des desoxyribonucleotides, les precurseurs de l'adn. Cette enzyme est inhibee par les superoxydes. La sous-unite r2 de la ribonucleotide reductase de e. Coli contient un radical tyrosinyle qui est absolument necessaire a l'activite enzymatique. Il est demontre qu'il est la cible specifique du superoxyde
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Costa, Aline Rocha de Paiva. "Revitaliza??o do Rio Golandim (RN/Brasil) ap?s d?cadas de contamina??o por efluentes industriais e dom?sticos: este rio est? recuperado?" Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18230.
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Previous issue date: 2012-05-31Environmental pollution causes the loss of the quality of aquatic resources and also affects the health of human beings. The Golandim River is located in S?o Gon?alo do Amarante (RN Brazil) and had its water recovered seven years ago by measurements of parameters of the water s quality analyses physicochemistry, microbiological and heavy metals. However, it is not well established if this river is truly recovered, so this study provides a wide knowledge about the quality of these waters. Therefore, this investigation was accomplished by assays of ecotoxicology utilizing Ceriodaphnia dubia and of genotoxicity of the river s water using a biomarker Tradescantia Pallida (Trad-MCN). In set, it carried through a study of environmental perception through questionnaires that approached questions related to the profile of the interviewed one, knowledge on the environment and of the river Golandim with the community that lives in the neighborhoods of the river to diagnosis as they perceive the environment where live and its problems. The assays of the water had been carried out by collecting samples in three different sites of the Golandim River. They were collected between the periods of December 2010 (dry season in the northeast of Brazil) and July 2011 (rainy season in the northeast of). The analysis of the data allowed observing that the majority of the inhabitants are adult and presents a global vision of what it is part of the environment, the majority mentions the pollution of the river as one of the problems of the city, considering it serious. The ecotoxicology assay showed that there was not acute toxicity in all three samples collected. Meanwhile, all these three samples demonstrated significant chronic toxicity. The results from the Trad-MCN assay presented an increase in the frequency of micronucleus in one of the sites analyzed (S3) (p<0.01), in both seasons collected. On the other hand, the sites S1 and S2 did not presented a significant increase of micronucleus using this bioassay. The analyses of chemicals detected an increase in the levels of some metals, in different seasons and samples, which can be associates with some compounds found in urban and industrial areas. On the other hand, the physicochemistries parameters demonstrated that the Golandim River is recouped, when compared with the values presented at the CONAMA s legislation. However, these results indicate the presence of compounds capable of inducing chromosomal mutation in plants. On the other hand, the parameters physicistchemistries demonstrate that the river Golandim is if recouping, since when compares the values observed with the legislation of the CONAMA. All these results point to the fact that the Trad-MCN assay was sensitive and efficient biomarker for chromosomal instability and the C. dubia ecotoxicology assay was as though an efficient biomarker of toxicity of water s quality. The results from Trad-MCN associated with the ecotoxicology demonstrates that these analyses are important for environmental monitoring, once the first bioassay described above indicates alterations at the standards of cells and the other one indicates alterations at the standards of organisms. This study alerts for the necessity to carry out biological assays for the analyses of the water s quality
A ?gua ? essencial para a manuten??o da vida, entretanto, a polui??o ambiental vem causando a perda da qualidade dos recursos h?dricos, afetando assim a sa?de humana. Este estudo avaliou a qualidade da ?gua do Rio Golandim no munic?pio de S?o Gon?alo do Amarante/RN/Brasil ap?s a realiza??o do plano de recupera??o atrav?s de medi??es de par?metros de qualidade de ?gua - an?lises f?sico-qu?micas, de metais pesados e microbiol?gicos al?m de incluir ensaio de ecotoxicidade com Daphnia dubia e teste que detecta a presen?a de compostos mutag?nicos em Tradescantia pallida (Trad-MCN). Em conjunto, foi realizado um estudo de percep??o ambiental atrav?s de question?rios que abordou quest?es relacionadas ao perfil do entrevistado, conhecimentos sobre o meio ambiente e do rio Golandim, com a comunidade que vive nas proximidades deste rio para diagnosticar como eles percebem o ambiente em que vivem e seus problemas. Os experimentos foram realizados a partir de amostras de ?gua coletadas em dezembro de 2010 (esta??o do ano seca) e em julho de 2011 (esta??o das chuvas) em tr?s pontos diferentes do rio Golandim. A an?lise dos dados de percep??o ambiental permitiu observar que a maioria dos moradores s?o adultos e apresentam uma vis?o global do que ? meio ambiente e a maioria menciona a polui??o do rio como um dos problemas do munic?pio, considerando-o grave. Os dados resultantes do ensaio ecotoxicol?gico n?o indicou efeito de toxicidade aguda, entretanto demonstrou toxicidade cr?nica para a m?dia de reprodu??o dos clad?ceros nas esta??es do ano seca e chuvosa, em todos os pontos amostrados, os resultados provenientes do ensaio Trad-MCN para a ?gua bruta mostrou resposta positiva, representada pelo aumento na frequ?ncia de micron?cleos, para um dos pontos analisados (P3) em ambas as esta??es de coleta. As an?lises qu?micas detectaram um aumento nos n?veis de alguns metais nos diferentes per?odos e amostras, que podem estar associados ainda ? presen?a de compostos de origem urbana e industrial. Contudo, os par?metros f?sico-qu?micos demonstram que o rio Golandim est? se recuperando, j? que quando se compara os valores observados com a legisla??o brasileira do CONAMA. Nossos resultados apontam para a presen?a na ?gua de compostos capazes de induzir muta??es, podendo gerar s?rios agraves ? sa?de da popula??o que utiliza e reside nas proximidades do Golandim, a qual ainda se sente insegura quanto a utiliza??o do mesmo. Desta forma, este estudo alerta para a necessidade de realizar ensaios biol?gicos al?m de empregar apenas as an?lises provenientes das medi??es f?sico-qu?micas para atestar a qualidade de um corpo d ?gua, como tamb?m da realiza??o de trabalhos de educa??o ambiental com a comunidade ribeirinha
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Benhamou-Batut, Fabienne. "Dosage plasmatique du Flunitrazepam par C. L. H. P. Dans un cadre d'étude toxicologique." Bordeaux 2, 1993. http://www.theses.fr/1993BOR2P110.
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Satchivi, Norbert M. "Toxicité de deux herbicides, l'imazaquine et le metsulfuron méthyle sur la croissance de plantules de mai͏̈s (zea mays) influence de l'antidote lab 145 138 h." Perpignan, 1996. http://www.theses.fr/1996PERP0223.
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Les imidazolinones et les sulfonylurees sont des herbicides inhibiteurs de l'acteloactate synthase (als), premiere enzyme commune a la voie de biosynthese des acides amines a chaine ramifiee. Cependant on ne sait pas comment l'inhibition de cette enzyme entraine l'arret des divisions cellulaires puis de la croissance et finalement la mort du vegetal. Dans cette etude, nous avons recherche a preciser certains effets secondaires de l'imazaquine (iq) et du metsulfuron methyle (msm). Nous avons d'abord precise les conditions de culture des caryopses ; il en ressort que l'obtention de plantules agees de trois jours necessite 6 h d'imbibition des caryopses avec 5 ml de milieu d'imbibition. Cela nous a permis d'analyse l'influence de l'antidote lab 145 138 h sur l'effet toxique des deux herbicides. Les resultats obtenus montrent qu'en absence de l'antidote, l'iq et le msm provoquent des reductions de 53 et 58% de l'elongation du coleoptile et de 72 et 84% de celle de la racine lorsque la dose utilisee est egale a 4000 nm. Cependant, le pretraitement des caryopses avec l'antidote a 70 m, amoindrit l'effet herbicide ; les reductions passent respectivement a 28 et 27% au niveau du coleoptile et a 60 et 68% au niveau racinaire. Cet antidote est donc capable d'assurer une protection partielle de la plantule contre les effets toxiques de l'iq et du msm. En ce qui concerne l'impact des deux herbicides sur la teneur en proteines solubles des apex coleoptilaires et racinaires, nous avons montre que les differents traitements herbicides provoquent une augmentation de 17 a 30% de la quantite de proteines des apex coleoptilaires lorsque la dose appliquee est comprise entre 1200 et 4000 nm. Toutefois, le pretraitement des caryopses avec l'antidote lab induit une diminution de l'effet herbicide ; l'accroissement de la teneur en proteines n'est plus alors que de 14 a 19% pour ces memes doses. Au niveau racinaire seule le msm a 4000 nm provoque une augmentation de 15% de la teneur en prot
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Khodami-Pour, Ali. "The Na+/H+ exchanger Nhx1 of Saccharomyces cerevisiae is essential to limit drug toxicity." Thèse, 2009. http://hdl.handle.net/1866/3543.
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Nhx1 est un antiport vacuolaire de Na+/H+ chez la levure Saccharomyces cerevisiae. Nhx1 joue un rôle important dans le maintien de l’homéostasie ionique du cytoplasme de la cellule. En effet, la mutation du gène NHX1 chez la levure nhx1Δ entraîne une perte de l’homéostasie cellulaire quand les cellules sont cultivées dans un milieu de faible osmolarité.
Ce travail rapporte pour la première fois, et contrairement à la cellule parentale,
que la mutation du gène NHX1 a pour effet une sensibilité du mutant nhx1Δ à une
variété des drogues et des agents cationiques et anioniques lorsque les cellules sont cultivées dans un milieu riche. En outre, dans ces conditions de culture, aucune sensibilité n’a été observée chez le mutant nhx1Δ quand les cellules sont traitées avec différentes concentrations de sel. Nous avons aussi démontré que la sensibilité du mutant nhx1Δ aux différents agents ainsi que la sécrétion de l’enzyme carboxypeptidase Y observé chez ce mutant n’ont pas été restauré lorsque les cellules sont cultivées dans des milieux avec différents pH ou avec différentes concentrations de sel.
Enfin, une analyse génétique a révélé que le mutant nhx1Δ montre un phénotype distinct d’autres mutants qui ont un défaut dans le trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi quand ces cellules sont traitées avec différents agents. Cette analyse prouve que la sensibilité de nhx1Δ aux différents agents n’est pas liée au trafic entre le compartiment pré-vacuolaire et l’appareil de Golgi.Nhx1 is an intracellular Na+/H+ exchanger localized to the late endosome in Saccharomyces cerevisiae. It is believed that Nhx1 plays a major role in pH-mediated vesicle trafficking, as nhx1Δ mutant is defective in maintaining the intracellular pH in the vacuoles and cytoplasm when grown in low osmolarity media. In this work, we reported novel drug sensitivities of the nhx1Δ mutant to a range of cationic and anionic agents when cells are grown in rich media. Unlike the low osmolarity media, the nhx1Δ mutant showed no sensitivity to salt. Furthermore, we showed that the drug phenotypes of the nhx1Δ mutant, as well as the secretion of the vacuolar protein carboxypeptidase Y, were not rescued by either altering the pH or salt concentration. Although, amino acid substitution of the phylogenetically conserved residue Glu355 for Ala (E355A) in Nhx1 resulted in sensitivity to genotoxic drug bleomycin, it was not observed for the non-conserved residue Glu371Ala (E371A). Moreover, genetic analysis revealed that the nhx1Δ mutant displayed distinct drug phenotypes in comparison to mutants that are defective in retrograde trafficking from the prevacuole to the late Golgi, excluding the possibility that the drug sensitivity of the nhx1Δ mutant is related to retrograde trafficking.
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Wu, Ya-Ching, and 吳雅靜. "Effects of Pressure-Assisted Ozonation on the H. azteca Acute Toxicity of Personal Care and Pharmaceutical Products in Wastewater Treatment Plant Sludges." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/92979544386997760210.
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碩士國立屏東科技大學
環境工程與科學系所
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This study aimed to understand the distribution of pharmaceutical and personal care products in sludges of three wastwater treatment plants (WWTPs), focusing on four kinds of target chemical compounds which are alkylphenol (nonylphenol (NP)), antibacterial agent (triclosan(TCS)), UV filter (Benzophenone-3 (BP-3)) and over-the-counter (Caffeine (CAF)). These four compounds went through pressure-assisted ozonation with different parameter in three WWTPs sites and were investigated their removal efficiency of activated sludge and dewatered sludge. The results shown that among three WWTPs, the detection rate of four target compounds up to 100%. Especially, the activated sludge sample detection rate of NP is the highest in WWTP A and the concentration is up to 17.19 ± 4.10 mg/kg, the dewatered sludge in WWTP B, the concentration of TCS is 13.29 ± 6.36 mg/kg, and the the highest TCS detectable concentration in WWTP C in dewatered sludge is 4.74 ± 5.59 mg/kg. Through the comparisons of different pressure-assisted ozonation parameter, the removal efficiency of NP and TCS is up to 70% and BP-3 is 90% using 150 psi pressure, 40 cycles, 5 min of ozonation reacting, ratio of soil to water is 1 to 20 and 2% of ozonation concentration. In addition, the potential ecological risk evaluation was completed with by the risk quotient (RQ) calculation which is the ratio of median effect concentration (LC50) and peak chemical concentration. Overall, the calculated RQ greater than ten for NP, TCS and BP-3 which caused greater ecological risk to the aquatic organisms.There are no significantly different when using the H. azteca organism toxicity to test ozonation before and after treatment in sludge. Therefore, it is suggested to extend the days to conduct organism toxicity for further study. The high detection frequency of target compounds shows that WWTPs still has high concentration of PPCPs after treatment, which cannot be ignored when disposal route of sludge is discussed in the future.
Books on the topic "H+ toxicity"
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Alberta. Ad Hoc Committee on H₂S Toxicity. Report on H₂S toxicity. [Edmonton, Alta.]: Alberta Health, 1988.
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Syme, Jocelyn. The toxicity of lactate oxidase due to hydrogen peroxide production in the cell lines K-562 and H-209. Sudbury, Ont: Laurentian University, 1992.
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John, Smith. Scientific Report on A. T. H. I. S. , or, Acquired Toxicity, Hyper Immunity, Syndrome: The New Killer Autoimmune Syndrome. Independently Published, 2020.
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(Producer), WHO, ed. Vol 49 IARC Monographs: Chromium, Nickel and Welding (IARC Monographs on the Evaluation of Carcinogenic Risks to H). World Health Organisation, 1990.
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(Producer), WHO, ed. Vol 36 IARC Monographs: Allyl Compounds, Aldehydes, Epoxides and Peroxides (IARC Monographs on the Evaluation of Carcinogenic Risks to H). World Health Organisation, 1985.
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(Producer), World Health Organization, ed. Man-Made Mineral Fibres and Radon. Vol 43 (IARC Monographs on the Evaluation of Carcinogenic Risks to H). World Health Organisation, 1988.
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(Producer), World Health Organization, ed. Vol 48 IARC Monographs: Some Flame Retardants and Textile Chemicals and Exposures in the Textile Manufacturing Industry (IARC Monographs on the Evaluation of Carcinogenic Risks to H). World Health Organisation, 1990.
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Sakaguchi, Hitoshi, and Takao Ashikaga. "The h-CLAT Method." In Alternatives for Dermal Toxicity Testing, 289–309. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-50353-0_21.
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Latham, Patricia S., and Susan B. Sepelak. "Endotoxin (LPS) Toxicity to Hepatocytes (H) In Vitro - Modulation by Macrophages (M)." In Immunobiology and Immunopharmacology of Bacterial Endotoxins, 151–58. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4613-2253-5_12.
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Parasuraman, Malathy, and Priyantha Weerasinghe. "Application of mutation breeding techniques in the development of green crop varieties in Sri Lanka: the way forward." In Mutation breeding, genetic diversity and crop adaptation to climate change, 76–82. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0008.
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Abstract The Department of Agriculture (DOA) in Sri Lanka initiated mutation breeding in the 1960s with the introduction of a cobalt-60 source. The first rice mutant variety, MI 273, was released for general cultivation in 1971. M1 273, derived from irradiation of the H-4 variety, was identified as a drought-tolerant variety. An indirect rice mutant variety, developed by crossing the short mutant line BW267-3 with a highly adaptable variety, was released as BW 372 in 2013. It is moderately tolerant to blast, bacterial leaf blight, brown plant hopper, gall midge and iron toxicity, and thus increases productivity to 3-4 t/ha on lands prone to iron toxicity. The most popular groundnut variety cultivated in the country, 'Tissa', is a mutant developed by irradiation with gamma-rays at 200 Gy. It showed attributes of high yield, medium maturity (90-100 days) and high oil content (42%). 'Tissa' presently covers 80% of the groundnut cultivated area in Sri Lanka. A sesame mutant line, derived from the variety MI-3 irradiated at 200 Gy with 60Co gamma-rays, was released as 'Malee' (ANK-S2) in 1993. It is a high-yielding variety (1.1-1.8 t/ha) resistant to Phytophthora blight. A cherry-type mutant tomato variety, developed by irradiation of seeds with gamma-rays (320 Gy), was released as 'Lanka Cherry' in 2010. Improved attributes are pear-shaped fruits and bacterial wilt resistance. Narrow genetic variability in many crops is a constraint to the development of new varieties adapted to the changing climate. Hence, the DOA is emphasizing integration of induced mutagenesis in conventional breeding programmes to develop resistant/tolerant varieties having high yield, quality and health-promoting functional properties in field and horticultural crops. The newly installed gamma irradiation chamber facilitates the creation of genetic variability in food crops, thus paving the way for the development of greener varieties.
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Alanis-Ramírez, Claudia Ivett, Liliana Ávila-Cordoba, Rubi Romero-Romero, and Reyna Natividad. "Biodiesel production as an alternative to reduce the environmental impact of University food courts." In CIERMMI Women in Science Engineering and Technology TXV, 37–50. ECORFAN, 2021. http://dx.doi.org/10.35429/h.2021.6.37.50.
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The objective of this work was to assess the environmental impacts of producing biodiesel by heterogeneous and homogeneous catalysis. The raw material for the process was the waste cooking oil (WCO) generated at 27 food courts of Autonomous University of the State of Mexico. The study was conducted by applying Life Cycle Assessment methodology and the environmental impacts were calculated with the SimaPro 9.1.0.11 PhD software with the Ecoinvent database. The method was CML-IA base line C3.06/EU25. The assessed impact categories were: Abiotic Depletion Potential (ADP, elements), Abiotic Depletion Potential (ADP, fossil fuels), Global Warming Potential (100 years) (GWP), Ozone Layer Depletion (ODP), Human Toxicity (HT), Freshwater Aquatic Ecotoxicity (FWAE), Marine Aquatic Ecotoxicity (MAE), Terrestrial Ecotoxicity (TE), Photochemical Oxidation (PO), Acidification (A) and Eutrophication (E). In addition, end point environmental indicators were also calculated (Ecosystems Quality, Human Health Damage and Resources Availability) by the method ReCiPe 2016 Endpoint (H) V1.04 / World (2010) H/A. The system boundary enclosed three main stages, WCO collection, pre-treatment and reaction (to produce biodiesel). It was concluded that the reaction stage is the one with the highest environmental impact. In this sense, the highest impact categories were ADP (fossil fuels) (105.56 MJ), GWP (8.91 kg CO2 eq) and MAE (2387.89 kg 1, 4-DB eq). Nevertheless, it was also found that the GWP for the heterogeneous process is 82.52 % lower than that calculated for the homogeneous process. In addition, the human health damage of the homogeneous process is 1.77 points and is higher than the observed with the heterogeneous process.
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"Early Life History of Fishes in the San Francisco Estuary and Watershed." In Early Life History of Fishes in the San Francisco Estuary and Watershed, edited by Swee J. Teh, Guo H. Zhang, Tom Kimball, and Foo C. Teh. American Fisheries Society, 2004. http://dx.doi.org/10.47886/9781888569599.ch16.
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<em>Abstract.</em>—Runoff from dormant spray applications to orchards can contain the insecticides diazinon and esfenvalerate, which may affect the health of the threatened splittail <em>Pogonichthys macrolepidotus</em>. To examine the potential effects of these two insecticides, splittail larvae were exposed to diazinon, esfenvalerate, and a mixture of the two insecticides in static renewal 96-h acute toxicity tests. Surviving fish were transferred to clean water for an additional 14 d (18 d total). Mortality, morphological anomalies, histopathology, and growth determinations were made to assess lethal and sublethal effects. The combination of diazinon and esfenvalerate produced less than additive (independent) toxicity. Diazinon (singly and in combination with esfenvalerate) produced latent toxicity after the 96-h exposure, as demonstrated by reduced growth and increased spinal deformities. Metabolic dysfunction in the liver and inflammation of the pancreas were likely related to slower growth of diazinon-exposed fish. These symptoms were almost absent from esfenvalerate-exposed fish. The use of 14-d EC50 values and the measurement of biomarkers may more accurately describe the effects of 96-h shortterm exposure to these insecticides than traditional 96-h LC50 values.
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Vargas-Bernal, Rafael. "Toxicity Analysis of Different Types of Two-Dimensional Nanomaterials Used in Biomedical Applications." In Implications of Nanoecotoxicology on Environmental Sustainability, 178–205. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-5533-3.ch009.
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The study of biological interactions with two-dimensional nanomaterials provides the scientific foundation for identifying and managing development risks in both biomedical and non-biomedical technologies. The purpose of this chapter is to carry out an analysis of the toxicity of two-dimensional materials in biomedical applications or in other applications where they could have contact with biological entities. The toxicity of graphene, graphdiyne, transition metal dichalcogenides (TMDs), MXenes, hexagonal boron nitride (h-BN), graphitic phase C3N4, phosphorene (BP), exfoliated pnictogens (antimonene, arsenene, bismuthene), Xenes (borophene), and layered metal oxides (LMOs) are analyzed. The different mechanisms involved in the interactions were identified to propose solutions to reduce or eliminate the adverse effects of their cytotoxicity. Future research topics that should be developed to ensure the safe use of two-dimensional nanomaterials in biomedical applications, before their use in commercial applications, are discussed.
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Balogun, Fatai O., and Saheed Sabiu. "Green Synthesis Application in Diabetes Therapy." In Therapeutic Use of Plant Secondary Metabolites, 238–68. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815050622122010013.
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The use of medicinal plants and or medicinal plants-aided nanoparticles(NPs) in the management of diabetes mellitus has progressively received wideracceptance over the years due to the accompanying side effects with conventionaltherapy. The review explores the application of green-synthesized nanostructures in thecontrol or management of diabetes as well as probable mechanism of NPs formationand possible toxicity. Information sourced from scientific databases including ScienceDirect, Google Scholar, PubMed, Web of Science, SciFinder, JSTOR revealed 58medicinal plants explored in the synthesis of four (4) NS such as gold, silver, zincoxide and platinum with established antidiabetic potential. The NS is characterized byvarying microscopic and or spectroscopic instruments such as UV-Vis, SEM, EDS,FTIR and XRD commonly are stable, smaller-sized and mostly crystalline in nature.The functional groups responsible for the reduction and stabilization of thenanoparticles are predominantly C-O, C-H, COOH, N-H found in phenols, flavonoids,alkaloids, proteins and so on. The review identified and revealed 45% studies with lessthan 5% (mostly from India) conducted on animal models for antidiabetic and toxicitydeterminations, respectively with none for clinical studies, indicating the need forintensified efforts on research on these identified plants and unidentified species fordrug development.
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Anderson, Brian J. "The non-steroidal anti-inflammatory drugs and acetaminophen." In Oxford Textbook of Paediatric Pain, 436–44. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199642656.003.0043.
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The non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (N-acetyl-p-aminophenol, APAP) are the commonest analgesic drugs used in childhood. Although both drugs act through inhibition of prostaglandin H2 synthetase (PGHS), acetaminophen lacks the anti-inflammatory effects of the NSAIDs. Neonatal acetaminophen hepatic clearance is reduced in premature neonates (5–10% adult rates) and increases to 30% adult rates in neonates born at term; adult rates (approximately 16–20 L/h/70 kg) are reached within the first year of life. NSAID clearance maturation, mostly through cytochrome P450 mixed oxidases, is more rapid. Concentration–response relationships suggest a maximum pain reduction of 5 or 6 on a 10-point scale for both drugs. Combination therapy does not increase this maximum effect but does prolong duration of analgesia. While both drugs have good safety profiles, dosing of both drug groups is tempered by concerns about toxicity. Acetaminophen hepatotoxicity is associated with single doses (〉250 mg/kg in preschool children, 〉150 mg/kg in adults) and therapy duration longer than 3 to 5 days (〉90 mg/kg/day).The most common minor adverse events in NSAID recipients are nausea, dizziness, and headache. More concerning is the potential of NSAIDs to cause gastrointestinal irritation, blood clotting disorders, renal impairment, neutrophil dysfunction, and bronchoconstriction. These adverse effects are uncommon provided care is taken with drug dose, duration of therapy, and recognition of contraindications.
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Anderson, Brian J. "The nonsteroidal anti-inflammatory drugs and acetaminophen." In Oxford Textbook of Pediatric Pain, edited by Bonnie J. Stevens, Gareth Hathway, and William T. Zempsky, 449–63. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198818762.003.0043.
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Nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (N-acetyl-p-aminophenol (APAP; paracetamol)) are the commonest analgesic drugs used in childhood. Though both drugs act through inhibition of prostaglandin H2 synthetase, acetaminophen lacks the anti-inflammatory effects of the NSAIDs. Neonatal acetaminophen hepatic clearance is reduced in premature neonates (5–10% adult rates) and increases to 30% adult rates in neonates born at term; adult rates (approximately 16–20 l/h/70 kg) are reached within the first year of life. NSAID clearance maturation, mostly through cytochrome P450 mixed oxidases, is more rapid. Concentration–response relationships suggest a maximum pain reduction of 5 or 6 on a 10-point scale for both drugs. Combination therapy does not increase this maximum effect but does prolong duration of analgesia. Whilst both drugs have good safety profiles, dosing of both drug groups is tempered by concerns about toxicity. Acetaminophen hepatotoxicity is associated with single doses (>250 mg/kg in preschool children, >150 mg/kg in adults) and therapy duration longer than 3–5 days (>90 mg/kg/day).The most common minor adverse events in NSAID recipients are nausea, dizziness, and headache. More concerning is the potential of NSAIDs to cause gastrointestinal irritation, blood clotting disorders, renal impairment, neutrophil dysfunction, and bronchoconstriction. These adverse effects are uncommon provided care is taken with drug dose, duration of therapy, and recognition of contraindications.
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Dey, Satarupa. "Role of Bacterial Chromate Reductase in Bioremediation of Chromium-Containing Wastes." In Recent Advancements in Bioremediation of Metal Contaminants, 72–96. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-4888-2.ch005.
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Chromium toxicity is a major environmental concern as it is the chief environmental pollutant released by paint, stainless steel, and mining industries. In nature, chromium exists in two stable valance states: Cr(VI) and Cr(III). Cr(VI) is highly toxic and soluble at neutral pH, whereas Cr(III) is insoluble at normal pH and is less toxic. Thus, it is essential to draw strategies for mitigation of Cr(VI), and microbial reduction of toxic Cr(VI) has been identified as a bioremediation technique not only to detoxify chromium but also to recover the non-toxic Cr(III) by physical means. Chromate reductase, the central enzyme involved in bioreduction of Cr(VI) to Cr(III) may be both intracellular as well as extracellular in nature. Most of the chromate reductase enzyme belongs to the oxidoreductase group such as nitroreductase, iron reductase, quinone reductase, hydrogenase, flavin reductase, as well as NAD(P)H-dependent reductase. Detailed analysis of the structure of the enzymes will help us in the suitable application of these enzymes in bioremediation of metal-contaminated wastes.
Conference papers on the topic "H+ toxicity"
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TAVARES, JOSEINA MOUTINHO, Jorge Tadeu de Freitas, Anderson Silva de Oliveira, Paulo Moutinho Andrade de Souza, and Walter da Silva Junior. "EVALUATION OF TOXICITY IN SURGICAL STEEL PANS." In I South Florida Congress of Development. CONGRESS PROCEEDINGS I South Florida Congress of Development - 2021, 2021. http://dx.doi.org/10.47172/sfcdv2021-0013.
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This research aims to verify if the water heated in a surgical steel pan has metal contents since few studies are found involving this type of pot. The results have shown that only Al levels showed levels at the limit and above the values recommended by the Ministry of Health Consolidation Ordinance 5 / XX / 2017 after 40 h of discontinuous heating. This may have been caused by the pH between 4-5 of the deionized and drinking water used for heating. It is known that most metals are soluble in the acidic medium and, therefore, Al can be transferred to food. This shows that the level of salt contamination in foods heated continuously in these pans in an acid medium will most likely be significant and harmful. Thus, the intake of food prepared continuously in these pans may develop serious illnesses in people, such as Alzheimer s and Parkinson s. since metals, including Al, are cumulative in organisms and can cause pathogenic disturbances in humans
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Hawthorne, Steven B., Arnaud J. M. Lagadec, David J. Miller, and Peter J. Hammond. "Non-Oxidative Destruction of TNT, RDX, and HMX on Contaminated Soil Using Subcritical (Hot/Liquid) Water." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4792.
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Subcritical (hot/liquid) water was used in a simple static (non-flowing) vessel to treat three soils from former defense sites which were contaminated with the explosives TNT (12 wt.%), or RDX (0.62 wt.%) and HMX (0.16 wt. %). Significant degradation of RDX began at 100 C, and at 125 C for TNT and HMX, with the bulk of the undergraded explosives remaining in the soil rather than in the water phase. Based on HPLC/UV analysis, intermediate degradation products formed, but quickly degraded at < 250 C. Remediations performed using a generator-powered mobile pilot-scale unit (4 to 6 kg soil) with 4-L of water at 275 C for 1 h of real soils resulted in > 99.9% destrcution of TNT and HMX, and > 99.5% desstruction of RDX. None of the mutagenic nitroso derivatives of RDX and HMX were formed. “Microtox” acute toxicity tests with Vibrio fischeri showed no significant (compared to background) residual toxicity in either the process wastewaters or leachates from the treated soils. The operation is closed-loop (no air or water emissions), and process water can be recycled without treatment. Initial cost analysis indicates that the process should be competitive with other approaches such as bioremediation.
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Shupletsova, O. N. "Obtaining barley genotypes in selective in vitro systems with complex resistance to soil stress factors." In CURRENT STATE, PROBLEMS AND PROSPECTS OF THE DEVELOPMENT OF AGRARIAN SCIENCE. Federal State Budget Scientific Institution “Research Institute of Agriculture of Crimea”, 2020. http://dx.doi.org/10.33952/2542-0720-2020-5-9-10-99.
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The aim of the work was to develop selective in vitro systems and obtain on their basis the initial breeding material of spring barley adapted to adverse soil conditions – increased acidity, toxicity of aluminum and heavy metals, drought. In the process of research, optimal patterns for selecting callus lines on selective media using various combinations of stress factors were identified: Al3 + (20–40 mg/l), H+ (4.0–6.0 pH units), Cd2 + (10-20 mg/l), Mn2 + (100–250 mg/l) and osmotic (10–20 % polyethyleneglycol). In the proposed in vitro selective systems, more than a thousand regenerated plants were obtained. Varieties created on the basis of regenerants exceed the standard in yield, have high productive tillering (29.0–67.5 % higher than the standard) and dense spike (4.5–6.6 % higher than the standard). Their advantage is due to resistance to lodging, a high level of survival, germination and environment-forming activity of the root system.
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Baumgartner, C., B. A. Perret, E. Meili, M. Furlan, H. Friedli, and J. J. Morgen-thaler. "NORMAL IN VIVO KINETICS OF FACTOR VIII (F VIII) AND FACTOR IX (F IX) TREATED WITH TRI (N-BUIYL) PHOSPHATE (TNBP) AND TWEEN 80 FOR INACTIVATION OF VIRUSES." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644068.
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Heat treatment has been cxxnmonly used for the sterilisation of coagulation factor concentrates. This causes, however, considerable loss of coagulation factor activity? therefore alternative methods have been developed. Two new virus-inactivated coagulation factor preparations were recently introduced by our institution. Their manufacturing procedure includes a lipid solvent extraction step: The cryoprecipitate (F VIII preparation) or the first DEAE eluate (F IX preparation) is incubated with 0.3 % TNBP and 1 % Tveen 80 at 24°C for at least 12 hours. (Horowitz, Transfusion 25 : 516-522, 1985). Single doses of these preparations (F VIII: median 20.5, range 6-33 U/kg, F IX: median 25, range 9-46 U/kg body weight) were given intravenously to 28 hemophilic patients with minor or no bleeding. F VIII or F IX levels in plasma were determined before and at intervals up to 48 h after injection. The recovery was calculated from the maximum increase of activity and an plasma volume of 41 ml/kg body weight. The plasma half life was calculated according to the procedures described by Morfini (Thrcmb. Res. 42: I-III, 1986). Results are shown in the table below.No side effects were recorded. Hemostasis was satisfactory in all patients with bleedings (n = 13). These results are within the range expected for conventional and heat treated F VIII and F IX preparations. We conclude that the lipid solvent extraction procedure as used here does not influence the in vivo kinetics and the function of F VIII and F IX and does not induce any acute toxicity.
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"Molecular composition - inhibition activity relationships for humic substances narrow fractions sets obtained by solid-phase extraction." In Sixth International Conference on Humic Innovative Technologies "Humic Substances and Eco-Adaptive Technologies ”(HIT – 2021). Non-Commercial Partnership "Center for Biogenic Resources "Humus Sapiens" (NP CBR "Humus Sapiens"), 2021. http://dx.doi.org/10.36291/hit.2021.mikhnevich.001.
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Humic substances (HS) have a wide spectrum of biological activity including inhibitory activity against β-lactamases.1 The latter are capable of hydrolyzing beta-lactam antibiotics and represent one of the main pathways of bacterial antibiotic resistance. HS are characterized by low toxicity and good solubility in water. A use of HS for therapeutic purposes is hindered by extreme molecular heterogeneity and high level of isomeric complexity. Solid-phase extraction (SPE) fractionation in combination with ultra-high resolution mass spectrometry (FTICR MS) is a promising method to simplify this molecular system and isolate the most active components of HS. The aim of this work was to test various SPE fractionation schemes as an approach to directed isolation of the components with the given activity from HS. The sample of coal humic acids (CHA-G) was isolated from the commercial sodium humate “Genesis” and separated using SPE cartridge according to gradients in polarity1 and acidity2 inherent within the molecular components of HS. Inhibitory activity against β- lactamase TEM-1 and its mutants was measured using chromogenic substrate CENTA. Molecular composition of fractions was determined using FTICR mass spectrometer 15 T solariX (Bruker Daltonics) located at the Collective Use Center of Zelinsky Institute of Organic Chemistry of RAS. Molecular assignments were plotted into van Krevelen diagrams. The diagrams were binned into 20 cells are assigned to seven chemotypes, and occupational densities for each chemotype were calculated after Perminova.3 For the fractions separated by polarity, a substantial difference in the molecular composition was observed. Inhibitory activity grew along with an increase in hydrophobicity. The HS activity increased along with an increase in contribution of condensed tannins and phenylisopropanoids (O/C <0.5, H/C <1.4) and decreased along with contribution of hydrolyzed tannins (O/C> 0.5, H/C <1.4). The similar analysis was conducted for the fractions separated with regard to pKa value of the dominating functional groups. The most isomeric complex molecular components were defined, which can be found in different HS fractions, but they are identical in elemental composition. The data obtained make it possible to choose the most efficient fractionation method that effectively lowers the molecular complexity of HS and makes it possible to isolate the most active HS fractions. SPE-fractionation in combination with 2D chromatography is going to be used in our future studies to achieve high resolution separation and more reliable “molecular composition-activity” relationships. Further research might bring substantial advance in the field of directed design of biologically active humic-based materials and compositions. Acknowledgements. This work was supported by the grant of the Russian Science Foundation no 21-73-20202. The center of collective use of the Zelinsky IOC RAS is appreciated. The research was conducted in the framework of the Scientific-Educational School of the Lomonosov MSU “Future of the plant and global environmental change”. References 1. Mikhnevich et al., ACS Omega, 2021, https://doi.org/10.1021/acsomega.1c02841 2. Zherebker et al., Environ. Sci. Technol. 2020, 54, 2667−2677 3. Perminova, I. V. PAC, 2019, 91(5), 851
Reports on the topic "H+ 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.
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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.
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Specht, W. L., and B. Bowers. Toxicity of Water Samples Collected in the Vicinity of F and H Seepage Basin 1990-1995. Office of Scientific and Technical Information (OSTI), September 1996. http://dx.doi.org/10.2172/624642.
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Greenwood, K. P., M. E. Hane, and A. J. Lander. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site. Edited by C. Loehle and C. J. Richardson. Office of Scientific and Technical Information (OSTI), December 1990. http://dx.doi.org/10.2172/6267968.
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Elmann, Anat, Orly Lazarov, Joel Kashman, and Rivka Ofir. therapeutic potential of a desert plant and its active compounds for Alzheimer's Disease. United States Department of Agriculture, March 2015. http://dx.doi.org/10.32747/2015.7597913.bard.
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We chose to focus our investigations on the effect of the active forms, TTF and AcA, rather than the whole (crude) extract. 1. To establish cultivation program designed to develop lead cultivar/s (which will be selected from the different Af accessions) with the highest yield of the active compounds TTF and/or achillolide A (AcA). These cultivar/s will be the source for the purification of large amounts of the active compounds when needed in the future for functional foods/drug development. This task was completed. 2. To determine the effect of the Af extract, TTF and AcA on neuronal vulnerability to oxidative stress in cultured neurons expressing FAD-linked mutants.Compounds were tested in N2a neuroblastoma cell line. In addition, we have tested the effects of TTF and AcA on signaling events promoted by H₂O₂ in astrocytes and by β-amyloid in neuronal N2a cells. 3. To determine the effect of the Af extract, TTF and AcA on neuropathology (amyloidosis and tau phosphorylation) in cultured neurons expressing FAD-linked mutants. 4. To determine the effect of A¦ extract, AcA and TTF on FAD-linked neuropathology (amyloidosis, tau phosphorylation and inflammation) in transgenic mice. 5. To examine whether A¦ extract, TTF and AcA can reverse behavioral deficits in APPswe/PS1DE9 mice, and affect learning and memory and cognitive performance in these FAD-linked transgenic mice. Background to the topic.Neuroinflammation, oxidative stress, glutamate toxicity and amyloid beta (Ab) toxicity are involved in the pathogenesis of Alzheimer's diseases. We have previously purified from Achilleafragrantissimatwo active compounds: a protective flavonoid named 3,5,4’-trihydroxy-6,7,3’-trimethoxyflavone (TTF, Fl-72/2) and an anti-inflammatory sesquiterpenelactone named achillolide A (AcA). Major conclusions, solutions, achievements. In this study we could show that TTF and AcA protected cultured astrocytes from H₂O₂ –induced cell death via interference with cell signaling events. TTF inhibited SAPK/JNK, ERK1/2, MEK1 and CREBphosphorylation, while AcA inhibited only ERK1/2 and MEK1 phosphorylation. In addition to its protective activities, TTF had also anti-inflammatory activities, and inhibited the LPS-elicited secretion of the proinflammatorycytokinesInterleukin 6 (IL-6) and IL-1b from cultured microglial cells. Moreover, TTF and AcA protected neuronal cells from glutamate and Abcytotoxicity by reducing the glutamate and amyloid beta induced levels of intracellular reactive oxygen species (ROS) and via interference with cell signaling events induced by Ab. These compounds also reduced amyloid precursor protein net processing in vitro and in vivo in a mouse model for Alzheimer’s disease and improvedperformance in the novel object recognition learning and memory task. Conclusion: TTF and AcA are potential candidates to be developed as drugs or food additives to prevent, postpone or ameliorate Alzheimer’s disease. Implications, both scientific and agricultural.The synthesis ofAcA and TTF is very complicated. Thus, the plant itself will be the source for the isolation of these compounds or their precursors for synthesis. Therefore, Achilleafragrantissima could be developed into a new crop with industrial potential for the Arava-Negev area in Israel, and will generate more working places in this region.