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Relation Between Contraction and Metabolic Efficiency
Published in Samuel Sideman, Rafael Beyar, Analysis and Simulation of the Cardiac System — Ischemia, 2020
Joseph Kedem, M. Scheinowitz, E. Furman, J. Sonn, H. R. Weiss
Glucose concentrations were determined (in duplicate) with the aid of a kit from Sigma® using Technical Bulletin No. 510. Glucose oxidase reacting with glucose forms gluconic acid and hydrogen peroxide. Peroxidase catalyzes the oxidation of colorless Q-dianisidine by hydrogen peroxide. Oxidized O-dianisidine absorbs light at 425 to 475 nm. The intensity of the absorption is proportional to the glucose concentration. Lactic and pyruvic acids were also measured (in duplicate) using a Sigma® kit employing the enzyme lactic dehydrogenase and NADH/NAD oxidation-reduction, according to Technical Bulletins No. 726-UV and No. 826-UV. NADH absorbance is measured at 340 nm and 10 ml of blood sufficed for all the above-mentioned substrate analyses.
Brief History and Use of Chemical Warfare Agents in Warfare and Terrorism
Published in Brian J. Lukey, James A. Romano, Salem Harry, Chemical Warfare Agents, 2019
Harry Salem, Andrew L. Ternay Jr., Jeffery K. Smart
Germany’s use of chemical weapons on the battlefield began on October 27, 1914, when Germans fired shells loaded with dianisidine chlorosulfonate, a tear gas, at the British near Neuve Chapelle. This tear gas normally produced violent sneezing. In this case, however, the chemical dispersed so rapidly in the air that the British never knew they had been attacked with gas (Charles, 2005). Following this experiment, the Germans continued to test other potential chemical weapons. In mid-December 1914, Haber’s assistant was killed while working on an arsenic-containing weapon (cacodyl: (CH3)2As–As(CH3)2). In January 1915, the Germans used xylyl bromide (T-Stoff) against the Allies, but it was so cold that the gas froze and settled in the snow.
Anisakis
Published in Dongyou Liu, Laboratory Models for Foodborne Infections, 2017
Mauricio Afonso Vericimo, Gerlinde Teixeira, Israel Figueiredo, Janaina Ribeiro, Maria Augusta Moulin Fantezia, Sergio Carmona São Clemente
Knowing that essential oils can irritate the mucosa, gut inflammatory reaction was studied after oral administration of the tested compounds.161 A marker of neutrophilic infiltration is the titration of myeloperoxidase activity (MPO), determined by solubilization of myeloperoxidase with hexadecyltrimethylammonium bromide and measured with a dianisidine-H2O2 assay.162
Benzo-a-pyrene-induced reproductive toxicity was abated in rats co-treated with taurine
Published in Toxin Reviews, 2022
Solomon E. Owumi, Opeoluwa Popoola, Moses T. Otunla, Uche A. Okuu, Eseroghene S. Najophe
Testicular and epididymal nitric oxide (NO) levels were estimated by the methods by Green et al. (1982). An equal volume of Griess reagent and samples was incubated for 15 min; subsequently, the mixture's absorbance was read (540 nm), and NO level in the sample calculated by extrapolation using a standard curve. Myeloperoxidase's (MPO) activity was estimated spectrophotometrically by the modified method described by Trush and previously reported (Trush et al.1994). In the presence of H2O2, MPO catalyzes the oxidation of o-dianisidine to produce a brown colored product with an absorbance of 470 nm. Moreover, testicular and epididymal TNF-α levels were analyzed as previously reported (Owumi et al.2020) by Enzyme-Linked Immunosorbent Assay (ELISA) kits (Elabscience Biotechnology, Beijing, China) with the aid of Molecular Devices SpectraMaxTM 384 multi-plate reader (San Jose, CA) following the manufacturer’s manual.
Oxidative degradation perturbs physico-chemical properties of hemoglobin in cigarette smokers: a threat to different biomolecules
Published in Inhalation Toxicology, 2021
Payel Biswas, Paromita Seal, Jyotirmoy Sikdar, Rajen Haldar
The peroxidase like activities of nonsmoker and smoker’s Hb were estimated according to the method of Everse et al. (1994). Reaction mixture of 2 ml contained 10 × 10−6 M Hb and 0.002% o-dianisidine in 0.05 M citrate buffer, pH 5.4. The reaction was initiated adding 1 × 10−3 M H2O2. The absorbance was recorded at 450 nm. Peroxidase like activity was further confirmed in 12% polyacrylamide discontinuous gel, where 10 × 10−6 M Hb from smoker and nonsmoker were added into four wells and run at 70 − 80 Volts. After completing the electrophoresis, one pair of nonsmoker and smoker’s samples were stained with Coomassie brilliant blue for identification of proper loading. Another pair was washed with 3:7 (v/v) methanol: acetic acid solutions for 10 min. A fresh o-dianisidine solution (6 × 10−6 M) was prepared in methanol. Immediately before use, 3 parts of the o-dianisidine solution were mixed with seven parts of 0.25 M sodium acetate at pH 5.0. The gels were immersed in this mixture at room temperature in dark. After 1 to 2 hrs with occasional mixing (every 10 − 15 min), H2O2 was added to a final concentration of 1 × 10−3 M. The staining was visible within 5 min and increased in intensity over the next 30 min. Then the gel was placed in 3:7 isopropanol: 0.25 M sodium acetate, pH 5.0. After removal of any precipitated o-dianisidine, the gel was ready for densitometric analysis (Thomas et al. 1976).
Chloroform extract of Calliandra portoricensis inhibits tumourigenic effect of N-methyl-N-nitrosourea and benzo(a)pyrene in breast experimental cancer
Published in Drug and Chemical Toxicology, 2022
Adedoyin O. Adefisan, Solomon E. Owumi, Kehinde O. Soetan, Oluwatosin A. Adaramoye
The method of Trush et al. (1994) was used to estimate the reaction between O-dianisidine and hydrogen peroxide. The MPO catalyzed the oxidation of O-dianisidine to yield a brown colored product (oxidized O-dianisidine product) and optical density was taken at 460nm using a spectrophotometer. In brief, sample (7μL) was added to O-dianisidine (200μL) and diluted H2O2 (50μL). The optical density was observed for 3minutes. A unit of MPO activity may be defined as the amount of MPO that caused a change in absorbance at 460nm for 3min.