Manganese is absorbed mainly via ingestion, but can also be inhaled. It binds to alpha-2-macroglobulin, albumin, or transferrin in the plasma and is distributed to the brain and all other mammalian tissues, though it tends to accumulate more in the liver, pancreas, and kidney. Manganese is capable of existing in a number of oxidation states and is believed to undergo changes in oxidation state within the body. Manganese oxidation state can influence tissue toxicokinetic behavior, and possibly toxicity. Manganese is excreted primarily in the faeces. (L228)
Manganese is a cellular toxicant that can impair transport systems, enzyme activities, and receptor functions. It primarily targets the central nervous system, particularily the globus pallidus of the basal ganglia. It is believed that the manganese ion, Mn(II), enhances the autoxidation or turnover of various intracellular catecholamines, leading to increased production of free radicals, reactive oxygen species, and other cytotoxic metabolites, along with a depletion of cellular antioxidant defense mechanisms, leading to oxidative damage and selective destruction of dopaminergic neurons. In addition to dopamine, manganese is thought to perturbations other neurotransmitters, such as GABA and glutamate. In order to produce oxidative damage, manganese must first overwhelm the antioxidant enzyme manganese superoxide dismutase. The neurotoxicity of Mn(II) has also been linked to its ability to substitute for Ca(II) under physiological conditions. It can enter mitochondria via the calcium uniporter and inhibit mitochondrial oxidative phosphorylation. It may also inhibit the efflux of Ca(II), which can result in a loss of mitochondrial membrane integrity. Mn(II) has been shown to inhibit mitochondrial aconitase activity to a significant level, altering amino acid metabolism and cellular iron homeostasis. (L228)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌物分类
对人类不具有致癌性(未被国际癌症研究机构IARC列名)。
No indication of carcinogenicity to humans (not listed by IARC).
Manganese mainly affects the nervous system and may cause behavioral changes and other nervous system effects, which include movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as “manganism”. (L228)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
暴露途径
所有暴露途径均可能产生严重的局部影响。
Serious local effects by all routes of exposure.
来源:ILO-WHO International Chemical Safety Cards (ICSCs)
Adult channel catfish Ictalurus punctatus were exposed to waterborne potassium permanganate for 12 wk to determine if such exposure would alter the manganese content of axial muscle or liver tissue. Continuous exposure to 0.5 mg KMnO4 or exposure to 1 or 2 mg KMnO4/L on alternate days did not cause a significant incr in manganese in axial muscle or liver tissue. The mean (|SE) concn of manganese in axial muscle of unexposed controls was 0.262 | 0.018 mg/kg (wet weight). Means of scle could be detected within groups. The mean (|SE) concn of manganese in liver tissue of controls was 1.67 | 0.09 mg/kg (wet weight). Manganese concns in liver tissue of the three exposure groups were 1.57 | 0.07 mg/kg, 1.68 | 0.08 mg/kg, and 1.58 | 0.10 mg/kg, for 0.5 (continuous), 1, or 2 mg/L (alternate days), respectively. Manganese was thought to accumulate in liver tissue, however, there were no statistically significant differences between those groups & the controls.
IONIZABLE LIPIDS AND LIPID NANOPARTICLE COMPOSITIONS FOR THE DELIVERY OF NUCLEIC ACIDS
摘要:
Novel ionizable lipids are provided. Also provided are novel lipid nanoparticle compositions for the delivery of nucleic acid material to cells in vitro and in vivo with different and improved pharmacokinetic profiles as compared to what is typically observed in the art. Also provided are methods for using the compositions in research and as therapeutics.
The kinetics and the mechanism of oxidative decarboxylation of benzilic acid by acidic permanganate (stopped-flow technique) An autocatalytic study
作者:Sairabanu A Farokhi、Sharanappa T Nandibewoor
DOI:10.1139/v04-102
日期:2004.9.1
The kinetics of the oxidation of benzilic acid by potassium permanganate in an acidic medium were studied spectrophotometrically. The reaction followed a two-stage process, wherein both stages of the reaction followed first-order kinetics with respect to permanganate ion and benzilic acid. The rate of the reaction increased with an increase in acid concentration. Autocatalysis was observed by one of
3-ARYL PROPIOLONITRILE COMPOUNDS FOR THIOL LABELING
申请人:UNIVERSITE DE STRASBOURG
公开号:US20160145199A1
公开(公告)日:2016-05-26
The present invention relates to a process for labeling compounds comprising thiol moieties with 3-arylpropiolonitrile compounds, to 3-arylpropiolonitrile compounds substituted with tag moieties and to specific 3-arylpropiolonitrile linkers.
A method for forming an imine comprises reacting a first reactant comprising a hydroxyl functionality, a carbonyl functionality, or both a hydroxyl functionality and a carbonyl functionality with a second reactant having an amine functionality in the presence of ordered porous manganese-based octahedral molecular sieves and an oxygen containing gas at a temperature and for a time sufficient for the imine to be produced.
desired. In this study, we have successfully developed manganese oxide-based efficient heterogeneous catalysts for aerobic oxygenation of sulfides. Firstly, we prepared four kinds of manganese oxides possessing different crystal structures, such as α-MnO2, β-MnO2, γ-MnO2, and δ-MnO2, and their structure–activity relationships were examined for the aerobic oxygenation of thioanisole. Amongst them, α-MnO2