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American Industrial Hygiene Association... May 1981Recent data from animal tests, case reports, and other sources about the carcinogenic effects and metabolism of benzidine-, o-tolidine-, and o-dianisidine-based dyes...
Recent data from animal tests, case reports, and other sources about the carcinogenic effects and metabolism of benzidine-, o-tolidine-, and o-dianisidine-based dyes have come to the attention of OSHA and NIOSH. Both agencies have reviewed the data and concluded that the findings establish the potential of these dyes to cause cancer in humans. OSHA and NIOSH conclude that persons working with these dyes should be aware of the potential health hazards that could result from excessive exposure to them. The intent of this document is to summarize the information available on the carcinogenic effects and metabolism of benzidine-, o-tolidine-, and 0-dianisidine-based dyes and to provide guidance so that employers, employees, and physicians may work together to reduce potential health hazards that could result from excessive exposure to these dyes.
Topics: Animals; Benzidines; Carcinogens; Coloring Agents; Cricetinae; Dianisidine; Dogs; Female; Humans; Male; Mice; Occupational Diseases; Protective Devices; Rats; Rats, Inbred F344
PubMed: 7223641
DOI: No ID Found -
European Journal of Pharmacology Oct 1991Free radical mechanisms have been implicated in diabetic microangiopathy. Agents that scavenge free radicals may be beneficial. We assessed the scavenging ability of two...
Free radical mechanisms have been implicated in diabetic microangiopathy. Agents that scavenge free radicals may be beneficial. We assessed the scavenging ability of two sulphonylureas, gliclazide and glibenclamide, in vitro. The assay which employs o-dianisidine sensitised by riboflavin can be used to distinguish between superoxide scavengers and general scavengers. The former species lead to an augmentation while the latter has an inhibitory effect. The drugs were added in final concentrations of 0.5, 1.0, 2.5 and 5.0 micrograms/ml. The percentage inhibition (mean +/- S.D.) for each concentration of gliclazide respectively was 11.0 +/- 2.5%, 20.8 +/- 2.9%, 31.4 +/- 2.2% and 47.2 +/- 0.8%. Glibenclamide had no scavenging effects. The results demonstrate that gliclazide is a powerful general free radical scavenger in vitro. We postulate that this scavenging quality of gliclazide may be important in diabetes.
Topics: Dianisidine; Free Radical Scavengers; Gliclazide; Oxidation-Reduction; Oxygen; Photochemistry; Sulfonylurea Compounds
PubMed: 1800127
DOI: 10.1016/0922-4106(91)90069-t -
Biochemical and Biophysical Research... Jun 2018Chionodraco hamatus is a teleost within the suborder Notothenioidei, the members of which are known to lack functional erythrocytes with modified hematopoiesis....
Chionodraco hamatus is a teleost within the suborder Notothenioidei, the members of which are known to lack functional erythrocytes with modified hematopoiesis. Hematopoiesis is an essential process during the development of animals, where it is tightly regulated by many different transcription factors, signaling proteins, chromatin modifications, and microRNAs (miRNAs). The miRNAs are known to regulate the expression of their target genes at the post-transcriptional level. However, little is known about the miRNA-mediated regulation of hematopoiesis. In this study, we confirmed that miR-152 plays a crucial role in hematopoiesis during the development of C. hamatus. The overexpression of miR-152 reduced hematopoiesis according to the decreased expression of GATA1 and reduced o-dianisidine staining of hemoglobin. Mechanistically, reduced hematopoiesis was regulated by the miR-152-mediated down-regulated expression of GATA1. Bioinformatics analysis was used to predict the target gene of miR-152. Western blotting as well as dual luciferase and EGFP reporter assays were employed to investigate the expression of GATA1 mediated by miR-152. Finally, verification experiments in the zebrafish autologous model strongly supported the effect of miR-152 on hematopoiesis. In conclusion, we suggest that miR-152 is a novel molecular factor that regulates hematopoiesis during the development of C. hamatus by down-regulating the expression of GATA1.
Topics: Animals; Erythropoiesis; Fish Proteins; GATA1 Transcription Factor; Gene Expression Regulation; MicroRNAs; Perciformes
PubMed: 29753742
DOI: 10.1016/j.bbrc.2018.05.053 -
Indoor Air Mar 2021With an increasing use of indoor disinfectants such as chlorine (Cl ) and hypochlorous acid, a convenient sampler for estimating exposure to oxidants, such as effective...
With an increasing use of indoor disinfectants such as chlorine (Cl ) and hypochlorous acid, a convenient sampler for estimating exposure to oxidants, such as effective chlorine, is necessary. Here, we developed a personal passive air sampler (PPAS) composed of a redox dye, o-dianisidine, in a polydimethylsiloxane (PDMS) sheet. o-Dianisidine readily reacts with gaseous oxidants generated by bleach usage, and its color changes as the reaction progresses; hence, personal exposure to effective chlorine could be easily detected by the naked eye, while cumulative exposure could be determined by measuring concentrations of o-dianisidine reacting with it. The PPAS was calibrated, and a sampling rate of 0.00253 m /h was obtained using a small test chamber. The PPAS was tested with the help of ten volunteers whose personal exposure to Cl -equivalent gas was estimated after bathrooms were cleaned using spray and liquid-type household disinfection products, and the accumulated exposure-gas concentrations ranged from 69 to 408 ppbv and 148 to 435 ppbv, respectively. These PPAS-derived exposure concentrations were approximately two orders lower than those estimated using ConsExpo, suggesting a significant overestimation by prevailing screening models, possibly due to the ignorance of transformation reactions.
Topics: Air Pollutants; Air Pollution, Indoor; Chlorine; Dimethylpolysiloxanes; Disinfectants; Disinfection; Environmental Monitoring; Humans; Hypochlorous Acid; Inhalation Exposure
PubMed: 32978992
DOI: 10.1111/ina.12747 -
Zebrafish Aug 2016Thrombosis is a leading cause of death and the development of effective and safe therapeutic agents for thrombotic diseases has been proven challenging. In this study,...
Thrombosis is a leading cause of death and the development of effective and safe therapeutic agents for thrombotic diseases has been proven challenging. In this study, taking advantage of the transparency of larval zebrafish, we developed a larval zebrafish thrombosis model for drug screening and efficacy assessment. Zebrafish at 2 dpf (days post fertilization) were treated with phenylhydrazine (PHZ) and a testing drug for 24 h. Tested drugs were administered into the zebrafish either by direct soaking or circulation microinjection. Antithrombotic efficacy was quantitatively evaluated based on our previously patented technology characterized as an image analysis of the heart red blood cells stained with O-dianisidine staining. Zebrafish at 2 dpf treated with PHZ at a concentration of 1.5 μM for a time period of 24 h were determined as the optimum conditions for the zebrafish thrombosis model development. Induced thrombosis in zebrafish was visually confirmed under a dissecting stereomicroscope and quantified by the image assay. All 6 human antithrombotic drugs (aspirin, clopidogrel, diltiazem hydrochloride injection, xuanshuantong injection, salvianolate injection, and astragalus injection) showed significant preventive and therapeutic effects on zebrafish thrombosis (p < 0.05, p < 0.01, & p < 0.001) in this zebrafish thrombosis model. The larval zebrafish thrombosis model developed and validated in this study could be used for in vivo thrombosis studies and for rapid screening and efficacy assessment of antithrombotic drugs.
Topics: Animals; Disease Models, Animal; Fibrinolytic Agents; Humans; Microinjections; Thrombosis; Zebrafish
PubMed: 27333081
DOI: 10.1089/zeb.2016.1263 -
Veterinary Sciences Oct 2023Ceruloplasmin (Cp) assessment in biological samples exploits the oxidase activity of this enzyme against several substrates, such as -phenylenediamine (-P), -dianisidine...
Ceruloplasmin (Cp) assessment in biological samples exploits the oxidase activity of this enzyme against several substrates, such as -phenylenediamine (-P), -dianisidine (-D) and, most recently, ammonium iron(II) sulfate (AIS). Once developed in humans, these assays are often used in veterinary medicine without appropriately optimizing in the animal species of interest. In this study, two assays using AIS and -D as substrates have been compared and validated for Cp oxidase activity assessment in horse's plasma. The optimization of the assays was performed mainly by varying the buffer pH as well as the buffer and the substrate molar concentration. Under the best analytical conditions obtained, the horse blood serum samples were treated with sodium azide, a potent Cp inhibitor. In the -D assay, 500 µM sodium azide treatment completely inhibits the enzymatic activity of Cp, whereas, using the AIS assay, a residual analytical signal was still present even at the highest (2000 µM) sodium azide concentration. Even though the analytical values obtained from these methods are well correlated, the enzymatic activity values significantly differ when expressed in Units L. A disagreement between these assays has also been detected with the Bland-Altman plot, showing a progressive discrepancy between methods with increasing analytical values.
PubMed: 37888575
DOI: 10.3390/vetsci10100623 -
Heliyon Jan 2021Various aromatic compounds that are structurally analogous to lignin were tested as possible/preferred substrates for purified laccase from newly isolated white rote...
Various aromatic compounds that are structurally analogous to lignin were tested as possible/preferred substrates for purified laccase from newly isolated white rote fungi, WRF03. The pH optima were tested using different substrates and kinetic studies were conducted at these pH optima. The pH optima in the presence of ABTS, α-naphthol, o-dianisidine, and catechol were 4.5 but 5.0 and 5.5 in the presence of guaiacol and pyrogallol, respectively. The initial velocities obtained from the kinetic study were analyzed using Graph Pad Prism 7 and Lineweaver-Burk plot to obtain kinetic constants ( and ) which were used to calculate substrate specificity. Amongst all the substrates tested, ABTS had the highest specificity-constant (181.51 Ms), and therefore, the most preferred substrate was followed by α-naphthol, -dianisidine, guaiacol, pyrogallol, and catechol. Resorcinol, orcinol, and veratryl alcohol did not display any considerable chemical shift in the presence of WRF03 laccase. Also, oxidation of phenolic substrates appeared to be dependent on the nature of the substituent groups and their relative position on the aromatic nucleus. Since most of these substrates are structural analogs of lignin and many recalcitrant environmental pollutants, the enzyme may find application in delignification, treatment of wastewater containing dyes, and polycyclic aromatic hydrocarbons (PAHs).
PubMed: 33537494
DOI: 10.1016/j.heliyon.2021.e06080 -
Biochemical and Biophysical Research... Jul 2019ABCD4, a member of the ATP-binding cassette transporter superfamily, is associated with the transport of vitamin B which is crucial for the development of red blood...
ABCD4, a member of the ATP-binding cassette transporter superfamily, is associated with the transport of vitamin B which is crucial for the development of red blood cells (RBCs) and may also be involved in its metabolism. However, the molecular function of ABCD4 during RBC development in zebrafish is mostly unknown. Using a morpholino-based knockdown approach, we found that abcd4-knockdown resulted in abnormal RBCs of irregular shapes and various sizes. o-Dianisidine staining, as an indicator of hemoglobin in RBCs, further confirmed that abcd4 morphants possessed fewer hemoglobinized cells and impaired blood circulation. Multiple protein sequence alignment revealed that the amino acid sequence for residues 13-292, which is the domain of vitamin B transport, of the zebrafish Abcd4 was highly conserved compared to that of other species. Accordingly, the abcd4 morphants can be rescued with human ABCD4, demonstrating a conserved role of ABCD4 in vertebrates. Notably, the vitamin B-deficient phenotype in abcd4 morphants, which causes anemia, was recapitulated in the newly-established abcd4 mutant, indicating the possibility that the abcd4 mutant could be used as a disease model of vitamin B-deficiency anemia. Our study provides an insight that the analysis of the newly-established abcd4 mutant may contribute to understanding its roles in ABCD4-related vitamin B-deficiency anemia and the associated pathogeneses in humans.
Topics: ATP-Binding Cassette Transporters; Anemia; Animals; Mutation; Vitamin B 12 Deficiency; Zebrafish
PubMed: 31113616
DOI: 10.1016/j.bbrc.2019.05.099 -
Methods in Molecular Biology (Clifton,... 2018The zebrafish, Danio rerio, is a powerful model for the study of erythropoiesis and defining the genetic basis of hematological diseases. The mechanisms of erythroid...
The zebrafish, Danio rerio, is a powerful model for the study of erythropoiesis and defining the genetic basis of hematological diseases. The mechanisms of erythroid differentiation are highly conserved in the zebrafish, permitting translational research studies and the modeling of erythropoiesis in higher vertebrates. An advantage of the system is the ability to manipulate gene expression and observe the effect on erythroid development in vivo, with relative ease and rapidity. The production of optically transparent embryos also makes it an attractive tool for visual analysis of circulating erythrocytes that can be used to study erythropoiesis. Through large-scale chemical mutagenesis screens, a variety of zebrafish blood mutants have been identified that are used for gene discoveries and the recapitulation of human diseases. Experimental techniques including in situ hybridization, o-dianisidine staining, flow cytometry, and microinjection are now commonly employed to study red blood cell biochemistry and erythropoiesis in the zebrafish. These techniques have been applied for identifying novel genes required for the hemoglobin synthesis, isolating blood cell lineages, visualizing genetic expression within erythroid tissues, and characterizing the phenotype of blood disorders. The applications of zebrafish methodology to the study of erythropoiesis and optimized step-by-step protocols are discussed in this chapter.
Topics: Animals; Biomarkers; Cell Differentiation; Cell Lineage; Drosophila Proteins; Erythrocytes; Erythropoiesis; Flow Cytometry; GATA1 Transcription Factor; GATA2 Transcription Factor; Gene Expression Regulation, Developmental; Hemoglobins; Humans; In Situ Hybridization; Microinjections; Models, Animal; Mutation; Phenotype; Vertebrates; Zebrafish
PubMed: 29076082
DOI: 10.1007/978-1-4939-7428-3_2 -
Ecotoxicology and Environmental Safety Jan 2021The environmental effects of additives have attracted increasing attention. Sodium dehydroacetate (DHA-S), as an approved preservative, is widely added in processed...
The environmental effects of additives have attracted increasing attention. Sodium dehydroacetate (DHA-S), as an approved preservative, is widely added in processed foods, cosmetics and personal care products. However, DHA-S has been recently reported to induce hemorrhage and coagulation aberration in rats. Yet little is known about the ecotoxicological effect and underlying mechanisms of DHA-S. Here, we utilized the advantage of zebrafish model to evaluate such effects. DHA-S induced cerebral hemorrhage, mandibular dysplasia and pericardial edema in zebrafish after 24 h exposure (48-72 hpf) at 50 mg/L. We also observed the defective heart looping and apoptosis in DHA-S-treated zebrafish through o-dianisidine and acridine orange staining. Meanwhile, DHA-S induced the deficiency of Ca and vitamin D3 in zebrafish. We further demonstrated that DHA-S stimulated Ca influx resulting in Ca-dependent mitochondrial damage in cardiomyocytes. Additionally, DHA-S inhibited glucose uptake and repressed the biosynthesis of amino acids. Finally, we identified that sodium bicarbonate could rescue zebrafish from DHA-S induced cardiovascular toxicity. Altogether, our results suggest that DHA-S is a potential risk for cardiovascular system.
Topics: Animals; Apoptosis; Calcium; Cardiotoxicity; Cell Line; Cerebral Hemorrhage; Dose-Response Relationship, Drug; Edema, Cardiac; Embryo, Nonmammalian; Embryonic Development; Heart; Myocardium; Pericardium; Pyrones; Rats; Zebrafish
PubMed: 33396133
DOI: 10.1016/j.ecoenv.2020.111613