Disease relevance of Methyl-tert-butyl ether

• Renal failure during dissolution of gallstones by methyl-tert-butyl ether [1].
• Induction of methyl tertiary butyl ether (MTBE)-oxidizing activity in Mycobacterium vaccae JOB5 by MTBE [2].
• A public/private partnership was established in 1997, under the administrative oversight of the American Petroleum Institute (API), to develop aquatic toxicity data sufficient to calculate ambient water quality criteria for methyl tertiary-butyl ether (MTBE), a gasoline oxygenate [3].
• Genotoxicity testing of methyl tertiary-butyl ether (MTBE) in the Salmonella microsuspension assay and mouse bone marrow micronucleus test [4].
• CYP2A6 coexpressed with human CYP reductase by a baculovirus expression system was also more active than CYP isoform 2E1 (CYP2E1) in the metabolism of MTBE, ETBE, and TAME [5].

Psychiatry related information on Methyl-tert-butyl ether

• Under these conditions it was observed that: (i) MTBE was degraded at high extent (90-99%) after 1h of reaction time, (ii) MTBE mineralization was low in all cases and reached only 31.7% at the best conditions, and (iii) In all cases, most of MTBE degradation occurred during the initial 3-5 min of reaction [6].

High impact information on Methyl-tert-butyl ether

• HPLC separations were carried out on a C30 reversed phase column with gradient elution using mobile phases containing water, methanol, and methyl-tert-butyl ether [7].
• Unexpected dilatation of the common bile duct after methyl tertiary butyl ether (MTBE) in rabbits. Possible implications to findings in man [8].
• Preliminary results suggest that MTBE is effective for dissolution of many gallbladder stones and some bile duct stones [9].
• Comparison of biostimulation versus bioaugmentation with bacterial strain PM1 for treatment of groundwater contaminated with methyl tertiary butyl ether (MTBE) [10].
• Methyl-tert-butyl-ether for treating bile duct stones: the British experience [11].

Chemical compound and disease context of Methyl-tert-butyl ether

• Addition of dimethylsulphoxide to methyl-tert-butyl ether and ethyl propionate increases cholesterol dissolving capacity and cholesterol gall stone dissolution in vitro [12].
• On the basis of these findings, the authors instituted two changes in their clinical protocol: All patients with gallstones are now examined by means of CT before chemical dissolution begins, and monooctanoin is instilled overnight before the MTBE procedure [13].
• Cholesterol gallstones from 5 patients were weight matched and incubated in 5 different solutions at 37 degrees C. These solutions consisted of methyl-tertiary butyl ether (MTBE), 90% mono-octanoin (MO), absolute alcohol, normal saline, and water [14].

Biological context of Methyl-tert-butyl ether

• A widely used gasoline additive, methyl tertiary butyl ether (MTBE), has been controversial, in part because of concerns about potential inhalation health effects and more recently because of added concerns about water contamination [15].
• Johnson et al. estimate that 9,000 leaking underground fuel tanks have caused MTBE contamination at community water supplies in the 31 states surveyed (excluding California and Texas) (6) [16].
• Biotransformation and kinetics of excretion of methyl-tert-butyl ether in rats and humans [17].
• With the contamination of groundwater by MtBE being a wide-ranging problem throughout the United States, it is essential to develop a technology capable of effectively remediating such aquifers in order to protect public health and the environment [18].
• The aerobic biodegradation of methyl tert-butyl ether (MtBE), a widely used fuel oxygenate, was investigated using a pilot-scale biomass-retaining bioreactor called a Biomass Concentrator Reactor (BCR) [18].

Anatomical context of Methyl-tert-butyl ether

• All animals receiving MTBE had different degrees of gallbladder necrosis, common bile duct necrosis and necrosis of intrahepatic bile ducts [19].
• Methyl-tertiary-butyl ether (MTBE) inhibits growth and induces cell transformation in rodent fibroblasts [20].
• Metyrapone, a potent inhibitor of P450 2B, consistently inhibited both the MTBE and ETBE dealkylations in microsomes from PB-treated rats [21].
• Kinetic studies on MTBE metabolism with human liver microsomes (n = 3) exhibited an apparent Michaelis constant (Km) of 28 to 89 microM and a maximum rate of metabolism (Vmax) of 215 to 783 pmol/min/mg [5].
• Previous studies have demonstrated the utility of MTBE in the setting of a large solitary gallstone impacted within the cystic duct as well as with multiple non-obstructing gallstones [22].

Associations of Methyl-tert-butyl ether with other chemical compounds

• Percutaneous transhepatic catheterization of the gallbladder for dissolution of cholesterol stones by instillation of methyl tert-butyl ether (MTBE) is an invasive therapeutic procedure [23].
• The mean relative percent difference (RPD) between measured and simulated VOC concentrations at the study site, accounting only for volatilization losses, was 50.6% for MTBE and 113% for toluene [24].
• Moreover, no detectable amounts of TDA were found in foam or MTBE extract of foam incubated in phosphate buffer, pH 7.4, at 37 degrees C for 5 days [25].
• This research suggests thatthe reported widespread contamination of groundwater with MTBE may also be due to heating oil and diesel fuel releases to the environment. used extensively for the past 20 years as a gasoline additive (up to 15 wt %) to reduce automobile carbon monoxide and hydrocarbon emissions [16].
• The half life of 7-10 h in blood and urine indicates that TBA would be more suitable than the parent compound as a biomarker for MTBE exposure [26].

Gene context of Methyl-tert-butyl ether

• Correlation analysis of the ether-metabolizing activities with individual CYP enzyme activities in the human liver microsomes showed that the highest degree of correlation was with CYP isoform 2A6 (CYP2A6)+ (r = 0.94 for MTBE, 0.95 for ETBE, and 0.90 for TAME), which is constitutively expressed in human livers and known to be polymorphic [5].
• These results provide strong evidence that CYP enzymes play a critical role in the metabolism of MTBE in human livers [5].
• Naturally occurring bacteria similar to the methyl tert-butyl ether (MTBE)-degrading strain PM1 are present in MTBE-contaminated groundwater [27].
• Carbon and hydrogen KIE values, calculated for different potential reaction mechanisms, imply that anaerobic biodegradation of MTBE follows a SN2-type reaction mechanism [28].
• The simultaneous application of ultrasound energy greatly accelerated the rate of cholesterol gallstone dissolution by methyl-tert-butyl ether (MTBE) [29].

Analytical, diagnostic and therapeutic context of Methyl-tert-butyl ether

• Endoscopy of the gallbladder as control of gallstone therapy with methyl-tert-butyl ether [30].
• The modalities for the non-surgical treatment of gallstones include oral dissolution by bile salts, local dissolution by methyl-tert-butyl-ether (MTBE), extracorporeal shockwave lithotripsy (ESWL) and percutaneous gallstone clearance [31].
• Occurrence of methyl tert-butyl ether (MTBE) in riverbank fiftered water and drnking water produced by riverbank filtration. 2 [32].
• After laparotomy, MTBE (5-11 ml) was infused into the gallbladder for eight hours [19].
• Dermal, oral, and inhalation pharmacokinetics of methyl tertiary butyl ether (MTBE) in human volunteers [33].

References