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13. Nat'l Academies Press, Drinking Water and Health, Volume 9 (1989), 2 DNA-Adduct Technology
- books.nap.edu
- 2 DNA-Adduct Technology The consensus of several recent meetings on DNA-adduct research has been that new assay systems for detecting and measuring DNA adducts and protein adducts have the potential to improve markedly the biologic bases for estimating the risks of human exposure to several important classes of environmental pollutants (Bartsch et al. ... New DNA-adduct technology embodies striking technologic improvements in sensitivity and specificity and permits measurement of mammalian re- sponse to small, intermittent environmental exposures. ... Those figures correspond to about 1 adduct per 10-7 bases in the lung and at least 1 adduct per 10-4 bases per day in the upper layer of skin. ...
- DNA-Adduct Technology 39 TECHNIQUES FOR DETECTING DNA ADDUCTS Chromatographic and Spectrometric Methods Chromatography has many variations, but all involve the flow of test material through tubing containing stationary material designed to adsorb the components of the test mixture selectively, and thus create different flow rates and a series of bands (chromatograms) by which their identity can be determined. ... Each analytic method possesses potentially good to high resolving power, but the suitability and sensitivity of any method or combination of methods commonly depends on the physicochemical properties of the adduct or the class of adducts to be tested. ...
- These immunoassays are simple to perform, inexpensive, and thus appropriate for human samples; but the antisera are chemical-spe- cific, and thus different antisera must be developed for each adduct of interest (Santella, 19881. ...
- DNA-Adduct Technology 41 two chemically identical haptens (in this case, DNA adducts) compete for an antibody binding site. ...
- Less useful for low-molecular-weight compounds, 32p_ postlabeling is more sensitive for aromatic or bulky hydrophobic adducts and has been able to show the extent and persistence of adduct formation in animals by more than 70 compounds, including aromatic hydrocarbons, ar- omatic amines, estrogens, and methylating agents (Gupta and Randerath, 1988~. ... Several studies have found a direct correlation between hemoglobin-adduct and DNA- adduct concentrations in exposed experimental animals (Adriaenssens et al. ...
- DNA-Adduct Technology 43 SENSITIVITY AND SPECIFICITY The intrinsic sensitivity of an assay to detect the molecular effect of a given hypothetical chemical is usually expressed as femtomoles (fmol; 10- Is moles) of adduct per milligram of DNA or protein. ... The estimates are approximations and sensitivity might vary by sev- eral orders of magnitude, depending on the physicochemical nature of the chemical or adduct. ... A high adduct concentration in urine is often assumed to indicate high internal exposure, but this assumption is not necessarily correct. ...
- DNA-Adduct Technology 47 opments in the study of DNA binding and protein binding provide a useful tool for beginning to acquire that understanding. ... APPLICATIONS OF DNA ADDUCT TECHNOLOGY General Utility in Risk Assessment DNA-adduct and protein-adduct technology is potentially useful in the processes of hazard identification and risk assessment. ... It appears that adduct tech- nology could be extremely valuable in estimating dosimetry and systemic distribution, in establishing possible target tissues or organs, and in deter- mining the potential for irreversible toxicity such as cancer, mutation, or developmental effects. Table 2-3 lists some potential applications of DNA-adduct analysis to the toxicologic evaluation of drinking water contaminants for risk assessment. The table is arranged as a matrix with the components of toxicity assessment on one axis and the potential contribution of DNA-adduct analysis on the other. ... Toxic effects can be adduct-specific, and three toxicologic components relationship of adducts to toxic response, muta- genicity, and species extrapolation might require methods that identify the adducts detected. ... , 32P-postlabeling) do not identify the DNA adduct detected. ... Specific adduct identification is needed to correlate toxicity with adducts and is desirable in studies of mutagenic activity. ... The last column of the table identifies the extent to which DNA- adduct technology can now be used routinely in toxicologic assessments; .
14. Entrez PubMed
- www.ncbi.nlm.nih.gov
- Relationship between environmental tobacco smoke exposure and carcinogen-hemoglobin adduct levels in nonsmokers.
- PURPOSE: The goal of this study was to examine the relationship between exposure to environmental tobacco smoke and levels of 4-ABP-hemoglobin adducts in nonsmoking pregnant women and to compare adduct levels in those women with levels in smoking pregnant women. ... RESULTS: The mean adduct level in smokers (184 pg of 4-ABP per gram of hemoglobin) was substantially higher than that in nonsmokers (22 pg/g). ... 5 micrograms/m3 weekly average nicotine) had median 4-ABP-hemoglobin adduct levels of 15 pg of 4-ABP per gram of hemoglobin, while those in the highest exposure category (> or = 2. ... Nonsmokers in this study had a median adduct level of 20 pg/g, and smokers had a median level of 143 pg/g. CONCLUSIONS: 4-ABP-hemoglobin adduct levels in nonsmokers were 14% of the levels in smokers, which is consistent with findings of 20% in two other studies. ... IMPLICATION: The relationship between environmental tobacco smoke exposure and 4-ABP-hemoglobin adduct levels supports epidemiologic evidence that environmental tobacco smoke is carcinogenic to passive smokers.
15. EVIDENCE OF ACETALDEHYDE-PROTEIN ADDUCT FORMATION IN RAT BRAIN AFTER LIFELONG CONSUMPTION OF ETHANOL -- Rintala et al. 35 (5): 458 -- Alcohol and Alcoholism
- alcalc.oupjournals.org
- EVIDENCE OF ACETALDEHYDEPROTEIN ADDUCT FORMATION IN RAT BRAIN AFTER LIFELONG CONSUMPTION OF ETHANOL .
- The animals were bled at 2-week intervals after the second immunization and the anti-acetaldehyde adduct serum was cross-adsorbed on human plasma proteinacetaldehyde conjugate linked to Sepharose 4B (Pharmacia, Uppsala, Sweden). ...
- For immunohistochemistry the sections were stained by the biotinstreptavidin complex method, employing the following steps: (1) pre-treatment of the cryo-sections with 3% hydrogen peroxide for 5 min followed by rinsing in PBS for 5 min; (2) pre-treatment with undiluted cow colostral whey (Hi-Col, Oulu, Finland) for 40 min to block non-specific binding followed by rinsing in PBS; (3) incubation for 1 h with a 1:200 dilution of the anti-acetaldehyde adduct antiserum in 1% BSAPBS followed by washing in PBS three times for 10 min; (4) treatment with cow colostral whey for 40 min followed by rinsing in PBS; (5) incubation for 1 h with biotinylated affinity-purified goat immunoglobulins to rabbit immunoglobulins (Dakopatts, Glostrup, Denmark), diluted 1:300 in 1% BSAPBS followed by washing in PBS three times for 10 min; (6) treatment with cow colostral whey for 5 min; (7) incubation for 30 min with a 1:600 dilution of peroxidase-conjugated streptavidin in PBS and washing in PBS three times for 5 min; (8) incubation for 2 min in diaminobenzidine (DAB) (9 mg DAB in 15 ml PBS plus 10 µl of 30% hydrogen peroxide). ...
- Tissue sections were stained with anti-acetaldehyde adduct antibodies as described in Materials and methods. ...
- Tissue sections were stained with anti-acetaldehyde adduct antibodies as described in Materials and methods. ...
- Tissue sections were stained with anti-acetaldehyde adduct antibodies as described in Materials and methods. ...
- (1987) has shown that free -aminolysine groups are important targets for adduct formation. ... Adduct formation with low concentrations of acetaldehyde has been demonstrated with microtubular proteins, which has been suggested to disturb neurotubulin polymerization (McKinnon et al. ...
- The present data indicate, however, that Purkinje cells were not preferential targets for acetaldehyde adduct formation, which may indicate that alcohol may act directly on Purkinje neurons, or it may act on other cells that in turn influence Purkinje neuronal activity. ...
- Thus, it appears that the present type of prolonged ethanol administration may favour adduct formation in brain structures, instead of liver. ...
- (1993) Effect of ethanol on cytochrome P450 (CYP2E1), lipid peroxidation and serum protein adduct formation in relation to liver pathology. ...
- (1988) Detection of a protein acetaldehyde adduct in the liver of rats fed alcohol chronically. ...
- (1992) Modification of proteins and other biological molecules by acetaldehyde: adduct structure and functional significance. ...
16. Endogenous DNA damage in humans: a review of quantitative data -- De Bont and van Larebeke 19 (3): 169 -- Mutagenesis
- mutage.oupjournals.org
- A list of endogenous DNA-damaging agents, processes and DNA adduct levels is presented. For the sake of comparison, DNA adduct levels are expressed in a standardized way, including the number of adducts per 106 nt. ...
17. Biological Relevance of Adduct Detection to the Chemoprevention of Cancer -- Sharma and Farmer 10 (15): 4901 -- Clinical Cancer Research
- clincancerres.aacrjournals.org
- Biological Relevance of Adduct Detection to the Chemoprevention of Cancer .
- The sensitivity of adduct detection in histologically normal tissue offers opportunities for the early detection of carcinogenesis. ...
18. Methemoglobin Oxidation of N-Acetylbenzidine to Form a Sulfinamide -- Zenser et al. 29 (4): 401 -- Drug Metabolism and Disposition
- www.dmd.org
- The possible peroxidatic formation of an N-acetylbenzidine (ABZ) sulfinamide adduct by methemoglobin was examined. ... The results demonstrate that methemoglobin can catalyze the peroxidatic formation of an ABZ sulfinamide adduct, perhaps by a diimine monocation intermediate. ...
- The hemoglobin adduct of the aromatic amine 4-aminobiphenyl has also been used for this purpose. This adduct is a sulfinamide that upon hydrolysis yields the primary amine for biomonitoring analysis (Green et al. ... The 4-aminobiphenyl hemoglobin adduct is elevated in smokers compared with nonsmokers (Bryant et al. ...
- This acetylated metabolite is also found as the major DNA adduct in human bladder cells (Rothman et al. , 1996) and as a hemoglobin adduct in rats exposed to benzidine (Birner et al. ... This DNA adduct, N'-(3'-monophospho-deoxyguanosin-8-yl)-N-acetylbenzidine, can be formed by cytochrome P-450 oxidation or prostaglandin H synthase peroxygenation of ABZ (Lakshmi et al. ... Peroxidation may be responsible for bladder cell DNA adduct formation (Rothman et al. ...
- This is the first study to demonstrate methemoglobin peroxidatic metabolism of an aromatic amine to form a sulfinamide adduct. ...
- In contrast, the adduct seems quite stable in the normal physiological pH range. ...
- Although ABZ, like benzidine, is peroxidatically activated to form a glutathione adduct, the mechanism of formation must be different. ...
- N'-(Glutathion-S-yl)-N-acetylbenzidine S-oxide has been detected as the main hemoglobin adduct in rats administered benzidine (Birner et al. , 1990; Zwirner-Baier and Neumann, 1998) and is anticipated as an adduct in hemoglobin from benzidine-exposed workers (Rothman et al. ... This article describes the formation of this adduct by a peroxidatic mechanism involving methemoglobin at pH < 7. ... Thus, plasma ABZ could be used by red cells to form the hemoglobin sulfinamide biomarker, and this adduct could be produced by peroxidatic metabolism. ...
19. Nucleic acid sequence and repair: role of adduct, neighbor bases and enzyme specificity -- Singer and Hang 21 (6): 1071 -- Carcinogenesis
- carcin.oupjournals.org
- Nucleic acid sequence and repair: role of adduct, neighbor bases and enzyme specificity .
- The literature on this topic has so far been limited and also diverse in terms of adduct type, base composition and repair systems. ...
- These results indicate that efficiency of repair is also adduct dependent. ...
- In the in vivo system described by these authors (46) it is now possible to separate the effect of the adduct position from that of the nearest neighbors. ...
- Sequences were also designed and synthesized to test the effects on repair of specific factors such as nearest neighbors, adduct type and position and thermodynamics. ...
- Another important aspect of the in vivo studies is that a given adduct can be repaired by multiple pathways. ...
- There were also indications that selective repair may be a factor which affects persistence of the adduct at specific sites in DNA when different repair backgrounds were used. ...
- The repair rate differed markedly from site to site over a time period of 030 h, as measured by the percentage of adduct remaining (Figure 2). ... These experiments show that quantitation of adduct, site and repair background can be used to study in vivo repair sequence specificity and that the data discussed above support the hypothesis that selectivity of repair of mutational events is an important factor in specificity of mutation. ...
- (1989) Single adduct mutagenesis: strong effect of the position of a single acetylaminofluorene adduct within a mutation hot spot. ...
- coli excinucleases are affected differently by the sequence context of acetylaminofluoreneguanine adduct. ...
- (1998) Rate of incision of N-acetyl-2-aminofluorene and N-2-aminofluorene adducts by UvrABC nuclease is adduct- and sequence-specific: comparison of the rates of UvrABC nuclease incision and protein-DNA complex formation. ...
- (1993) Effect of sequence, adduct type and opposing lesions on the binding and repair of ultraviolet photodamage by DNA photolyase and (A)BC excinuclease J. ...
- (1998) Differential cleavage of oligonucleotides containing the benzene-derived adduct 1,N6-benzetheno-dA, by the major human AP endonuclease HAP1 and Escherichia coli exonuclease III and endonuclease IV. ...
- (1998) 3,N4-ethenocytosine, a highly mutagenic adduct, is a primary substrate for Escherichia coli double-stranded uracil-DNA glycosylase and human mismatch-specific thymine-DNA glycosylase. ...
- (1995) N-2-aminofluorene and N-2 acetylaminofluorene adducts: the local sequence context of an adduct and its chemical structure determine its replication properties. ...
20. adduct
- www.infoplease.com
- adduct .
- See synonyms for adduct.
21. EVIDENCE OF ACETALDEHYDE-PROTEIN ADDUCT FORMATION IN RAT BRAIN AFTER LIFELONG CONSUMPTION OF ETHANOL -- Rintala et al. 35 (5): 458 -- Alcohol and Alcoholism
- alcalc.oupjournals.org
- EVIDENCE OF ACETALDEHYDEPROTEIN ADDUCT FORMATION IN RAT BRAIN AFTER LIFELONG CONSUMPTION OF ETHANOL .
22. Food Mutagens -- Goldman and Shields 133 (3): 965 -- Journal of Nutrition
- nutrition.org
- Not all adducts are promutagenic, and some sequences are more prone to allowing adduct formation or mutation. ...
- Each of these adduct assays has its usefulness and limitations, and all are challenged by sensitivity and/or specificity. ...
- The mechanism of action for aflatoxin B1 mutagenicity begins with metabolic activation by CYP3A4, CYP3A5 and/or CYP1A2 (7781) that forms an exo-8,9-epoxide and subsequent adduct formation and DNA damage (82,83). ...
- Measurements of the adduct or its metabolite in the urine indicate a dose-response effect for aflatoxin B1 exposure and liver cancer (46,63). ...
- The bay-region diol epoxide binds to DNA mostly as the N2-deoxyguanosine adduct (117). The metabolic activation by the CYP1A (118) and CYP1B (119,120) classes of enzymes are required for adduct formation. ...
- (1989) Interindividual variation among humans in carcinogen metabolism, DNA adduct formation and DNA repair. ...
- (1998) DNA adduct formation by polycyclic aromatic hydrocarbon dihydrodiol epoxides. ...
- (1999) DNA and protein adduct formation in the colon and blood of humans after exposure to a dietary-relevant dose of 2-amino-1-methyl-6-phenylimidazo 4,5-b pyridine. ...
- (1977) Structural identification of the major DNA adduct formed by aflatoxin B1 in vitro. ...
- (1997) Aflatoxin B1 induced DNA adduct formation and p53 mutations in CYP450-expressing human liver cell lines. ...
- (1997) Genotypes of glutathione transferase M1 and P1 and their significance for lung DNA adduct levels and cancer risk. ...
23. adduct
- www.factmonster.com
24. Patent 4716232: 1-(vinyl phosphonate adduct) pyrazolidinones
- www.freepatentsonline.com
- 1-(vinyl phosphonate adduct) pyrazolidinones.
- 1-(Vinyl phosphonate adduct) pyrazolidinones are intermediates to bicyclic pyrazolidinone antimicrobial compounds.
- The compounds of Formula I are 4-(substituted amino)-3-oxo-1-(vinyl phosphonate adduct)-1,2-pyrazolidinones, which for brevity's sake will be referred to as a "vinyl phosphonate adduct pyrazolidinone" compound, or, more simply, "vinyl phosphonate adduct" compound, in the following Specification. ...
- The species of carboxy-protecting group employed is not critical so long as the derivatized carboxylic acid is stable to the conditions of subsequent reaction(s) on other positions of the vinyl phosphonate adduct and can be removed at the appropriate point without disrupting the remainder of the molecule. ...
- The species of amino-protecting group employed is not critical so long as the derivatized amino group is stable to the conditions of subsequent reaction(s) on other positions of the vinyl phosphonate adduct and can be removed at the appropriate point without disrupting the remainder of the subsequent product molecule(s) Preferred amino-protecting groups are the allyloxycarbonyl, the t-butoxycarbonyl, and the trityl groups. ...
- 4 of the vinyl phosphonate adduct (Formula I) of the above reaction is determined by the C. ... Thus, a 4-(S) pyrazolidinone starting material will yield a 4-(S) vinyl phosphonate adduct (Formula I). ...
- 4 of the vinyl phosphonate adduct. Thus, a 4-(S) vinyl phosphonate adduct will yield a 7-(S) bicyclic pyrazolidinone product.
- The vinyl phosphonate adduct obtained from the alkylation reaction (Scheme 1) is acylated at the 2-position nitrogen with an oxalate ester acid chloride (after deprotonation of the pyrazolidinone with di(isopropyl)ethylamine). ...
- In the acylation reaction approximately one molar equivalent of the amine base and one molar equivalent or less of the oxalate reactant per equivalent of the adduct reactant are combined. ... The usual order is to combine the adduct and the oxalate reactants then add the amine base.
- The vinyl phosphonate adduct may be acylated in either chlorinated hydrocarbon or ether solvents. ...
- A preferred reaction sequence for the above Scheme 2 is to acylate the vinyl phosphonate adduct and then cyclize the product without isolating the 1,2-disubstituted pyrazolidinone. In this preferred combination reaction, the vinyl phosphonate adduct and the acylating reagent are combined in any order and in the stoichiometry discussed for the acylation reaction. ... The combination reaction requires more equivalents of di(isopropyl)ethylamine base per equivalent of adduct starting material (at least 2 versus at least 1) to effect both the acylation and the subsequent cyclization. ...
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