相关实验视频

Updated: Jul 23, 2026

A General Method for Detecting Nitrosamide Formation in the In Vitro Metabolism of Nitrosamines by Cytochrome P450s
07:38

A General Method for Detecting Nitrosamide Formation in the In Vitro Metabolism of Nitrosamines by Cytochrome P450s

Published on: September 25, 2017

核酸中的所有氧都会与致癌性乙基化剂发生反应

B Singer

    Nature
    |November 25, 1976
    PubMed
    概括

    乙烯基酸盐和乙烯基酸主要修改核酸氧基. 在单链RNA/DNA和双链DNA之间,反应性不同,O2-alkylpyrimidines显示出可变的糖化键.

    更多相关视频

    Formation of Covalent DNA Adducts by Enzymatically Activated Carcinogens and Drugs In Vitro and Their Determination by 32P-postlabeling09:33

    Formation of Covalent DNA Adducts by Enzymatically Activated Carcinogens and Drugs In Vitro and Their Determination by 32P-postlabeling

    Published on: March 20, 2018

    Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter12:15

    Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter

    Published on: May 29, 2019

    相关概念视频

    Oxidations of Aldehydes and Ketones to Carboxylic Acids01:15

    Oxidations of Aldehydes and Ketones to Carboxylic Acids

    Oxidation of aldehydes and ketones results in the formation of carboxylic acids. Aldehydes, bearing hydrogen next to the carbonyl group, are easily oxidized compared to ketones. This is because an aldehydic proton can easily be abstracted during oxidation.
    Aldehydes readily undergo oxidation in strong oxidizing agents such as potassium permanganate and chromic acid. The oxidation can also be carried out using mild oxidizing agents such as silver oxide. In fact, aldehydes can be easily oxidized...
    Toxic Reactions: Overview01:26

    Toxic Reactions: Overview

    When toxic substances penetrate the human body, they disseminate to various tissues, undergoing metabolic changes. This process yields reactive metabolites that may covalently bind with specific target molecules, resulting in toxicity.
    Toxicity falls into two primary categories: local and systemic.
    Local toxicity appears at the exposure site, such as protein denaturation caused by caustic substances.
    In contrast, systemic toxicity requires the toxic agent's absorption and distribution,...
    Mutagenicity and Carcinogenicity01:25

    Mutagenicity and Carcinogenicity

    Mutagenicity and carcinogenicity refer to the ability of drugs to cause genetic defects and induce cancer, respectively. The International Agency for Research on Cancer (IARC) classifies agents into four groups based on their carcinogenic potential. Group 1 agents are known human carcinogens; group 2A agents are probably carcinogenic to humans; group 3 agents lack data to support their role in carcinogenesis; and group 4 includes agents for which data support that they are not likely to be...
    Phase I Reactions: Oxidation of Carbon-Heteroatom and Miscellaneous Systems01:15

    Phase I Reactions: Oxidation of Carbon-Heteroatom and Miscellaneous Systems

    Oxidative reactions are pivotal in metabolizing numerous compounds, including pharmaceutical drugs. These reactions often occur in carbon-heteroatom systems, such as carbon-nitrogen, carbon-sulfur, and carbon-oxygen.
    In carbon-nitrogen systems, aliphatic and aromatic amines can undergo oxidative reactions. Secondary and tertiary amines, like those found in tricyclic antidepressants, can undergo N-dealkylation, a process that involves the oxidation of the alkyl group. In addition, oxidative...
    Bioactivation and Tissue Toxicity01:25

    Bioactivation and Tissue Toxicity

    Bioactivation is a metabolic process that transforms less reactive substances into highly reactive metabolites, initiating tissue toxicity. This transformation can lead to various toxic effects, including carcinogenesis and teratogenesis. Reactive metabolites are classified into two main types: electrophiles and free radicals.Electrophiles are electron-deficient species and are produced primarily by the enzyme cytochrome P-450 during the metabolism of compounds containing carbon, nitrogen, or...
    Spontaneous and Induced Mutations01:30

    Spontaneous and Induced Mutations

    Spontaneous mutations arise infrequently during DNA replication due to errors in the process. A key factor behind these errors is tautomeric shifts in nitrogenous bases, where bases transition from keto to enol forms or amino to imino forms. This shift can alter base-pairing rules, leading to mutations. Additionally, reactive oxygen species (ROS) arising from aerobic metabolism can damage DNA, resulting in depurination (loss of a purine base) or depyrimidination (loss of a pyrimidine base).