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Diseases of the Nervous System
Published in George Feuer, Felix A. de la Iglesia, Molecular Biochemistry of Human Disease, 2020
George Feuer, Felix A. de la Iglesia
Methyl chloride and methyl bromide also exert some toxicity on the nervous system.12,321,419 Methyl chloride is an odorless gas at room temperature and applied in the production of synthetic rubber and plastic. Some cases of methyl chloride-induced neurotoxicity has been reported in workers exposed to this compound. The toxic symptoms include staggering gait, weakness, tremors, blurred vision, and impairment of short-term memory. These abnormalities persist for over 10 weeks after exposure. Long-term exposure to dichloromethane exerts irreversible effects on the brain.500
Organic Chemicals
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Dichloromethane is a major component of paint strippers and degreasers. It is also used as a solvent for oils, fats, and waxes. At the EHC-Dallas, 15.7% of chemically sensitive patients studied had this substance identified in their blood. After using environmental control or outpatient treatment using heat depuration, 66% of these patients had cleared this substance from their blood.
Halogenated hydrocarbons
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
Dichloromethane (methylene dichloride, methylene chloride) is used as an ingredient in paint removers and as an industrial solvent. It has been used as an anesthetic agent, but fatalities occurred. The exposure limit is 100 ppm. The adult fatal dose by ingestion or inhalation is estimated to be 25 ml.
Polymer type effect on PLGA-based microparticles preparation by solvent evaporation method with single emulsion system using focussed beam reflectance measurement
Published in Journal of Microencapsulation, 2022
Muhaimin Muhaimin, Anis Yohana Chaerunisaa, Roland Bodmeier
The type and physical properties of polymer have influenced the opacity level of particle. All microparticles have different opacity level (Figure 2(a1–c1)). It is effect of polymer solubility in solvent dichloromethane. Polymers have high solubility in dichloromethane took longer time to solidify and stayed longer in the semi solid, the dispersed phase became more concentrated before it completely solidified. The polymer matrix is dense when it is allowed to shrink for a longer period of time. So, a gradual shrinkage of the droplet into solid microparticles was observed remain translucent. Mean diameter of polymeric microparticles ranged from 42 to 64 µm (FBRM) (Table 1). The particle size mean of microparticles which was prepared using the high viscosity of polymer organic solution were larger than those prepared with the low viscosity of polymer organic solution. This is caused by the more rapid solidification process occurring at the surface of embryonic microparticle droplets which resist in extensive shrinkage of embryonic microparticles droplets. Based on microscopy data, the square weighted mean of a chord length distribution is better estimation for mean particle diameter (Table 1).
Evaluation of non-clinical toxicity of extract and vouacapans from fruits of Pterodon pubescens Benth
Published in Drug and Chemical Toxicology, 2022
Vanessa Helena da Silva Souza, Rosanna Tarkany Basting, Ilza Maria de Oliveira Sousa, Núbia de Cássia Almeida Queiroz, João Ernesto de Carvalho, Mary Ann Foglio
The production of the dichloromethane extract in pilot-scale was standardized by Servat et al. (2012). In nociception and inflammation experimental models, Grando et al. (2017) demonstrated that the crude dichloromethane extract, contained both diterpene furans and acyclic diterpenes with higher potency than the aqueous extract, which only extracted vouacapans. Hence, the dichloromethane extract was chosen to continue with the toxicity evaluations. In this study, the extraction of Pterodon pubescens fruits provided 42.7% of crude dichloromethane extract (PPE) considering the ratio of the total mass. The extraction on a pilot-scale allowed producing in only one batch the sample amount needed for the execution of all the tests carried out throughout the study. Since dichloromethane is a highly volatile solvent (vapor pressure at 25 °C = 440 mmHg), the process of oven drying under vacuum ensured that all residual solvent was exhausted from the sample.
Bioanalytical strategies in drug discovery and development
Published in Drug Metabolism Reviews, 2021
Aarzoo Thakur, Zhiyuan Tan, Tsubasa Kameyama, Eman El-Khateeb, Shakti Nagpal, Stephanie Malone, Rohitash Jamwal, Chukwunonso K. Nwabufo
LLE offers an alternative to the PPT method which yields cleaner solutions (King et al. 2000; Chambers et al. 2007). However, it is more labor-intensive and requires a large volume of organics as compared to the PPT approach. The basic principle of LLE involves the separation of analytes from the interferences by partitioning the sample between two immiscible solvents. The organic solvent containing the analyte is then evaporated and the sample is reconstituted in starting mobile phase (Barroso et al. 2015). Ethyl acetate, dichloromethane, and methyl tertiary butyl ether are some of the commonly used organic solvents. The adjustment of sample pH is critical for LLE as non-ionized analytes are more efficiently extracted by organic solvents than charged species. As a rule of thumb, the pH of the sample should be adjusted within 2 units of the analyte pKa. For efficient extraction of basic analytes, the pH of the matrix should be at a pH at least 2 units above its pKa while for acidic analytes it should be at least 2 units below its pKa (Hendriks et al. 2007). LLE has been widely used for the quantification of small molecules in biological fluids (Desai et al. 2019; Domenech-Coca et al. 2019).