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International Journal of Occupational... 2016We report the results of the visual evoked potentials (VEP) examination in patients after severe poisoning by methanol.
OBJECTIVES
We report the results of the visual evoked potentials (VEP) examination in patients after severe poisoning by methanol.
MATERIAL AND METHODS
The group of 47 patients (38 males and 9 females) was assembled out of persons who survived an outbreak of poisoning by the methanol adulterated alcohol beverages, which happened in the Czech Republic in 2012-2013. The visual evoked potentials examination was performed using monocular checkerboard pattern-reversal stimulation. Two criteria of abnormality were chosen: missing evoked response, and wave P1 latency > 117 ms. Non-parametric statistical methods (median, range, and the median test) were used to analyze factors influencing the VEP abnormality.
RESULTS
The visual evoked potential was abnormal in 20 patients (43%), 5 of them had normal visual acuity on the Snellen chart. The VEP abnormality did not correlate significantly with initial serum concentrations of methanol, formic acid or lactate; however, it showed statistically significant inverse relation to the initial serum pH: the subgroup with the abnormal VEP had significantly lower median pH in comparison with the subgroup with the normal VEP (7.16 vs. 7.34, p = 0.04). The abnormality was not related to chronic alcohol abuse.
CONCLUSIONS
The visual evoked potentials examination appeared sensitive enough to detected even subclinical impairment of the optic system. Metabolic acidosis is likely to be the key factor related to the development of visual damage induced by methanol. The examination performed with a delay of 1-9 months after the poisoning documented the situation relatively early after the event. It is considered as a baseline for the planned long-term follow-up of the patients, which will make it possible to assess the dynamics of the observed changes, their reversibility, and the occurrence of potential late sequelae.
Topics: Adult; Aged; Evoked Potentials, Visual; Female; Formates; Humans; Hydrogen-Ion Concentration; Lactic Acid; Male; Methanol; Middle Aged; Visual Acuity; Young Adult
PubMed: 26988885
DOI: 10.13075/ijomeh.1896.00452 -
Physical Chemistry Chemical Physics :... Mar 2012Matrix isolation FTIR experiments have shown that methanol is a major product when argon gas doped with water and methane is exposed to an electrical discharge and...
Matrix isolation FTIR experiments have shown that methanol is a major product when argon gas doped with water and methane is exposed to an electrical discharge and condensed to a solid matrix at 11 K. Experiments with (2)H, (17)O and (18)O-labeled isotopologues show the mechanism for the methanol production is likely to be insertion of an excited oxygen atom in the (1)D state into a C-H bond of a methane molecule. In light of these experiments, the possibility of oxygen atom insertion into methane should be considered as a possible mechanism for the production of methanol in interstellar ices.
Topics: Argon; Electricity; Methane; Methanol; Spectroscopy, Fourier Transform Infrared; Water
PubMed: 22307542
DOI: 10.1039/c2cp22135g -
Fundamental and Applied Toxicology :... Jul 1993The toxicokinetics of intravenously administered methanol were examined in female Sprague-Dawley rats. Animals received a single administration of 100, 500, or 2500 mg...
The toxicokinetics of intravenously administered methanol were examined in female Sprague-Dawley rats. Animals received a single administration of 100, 500, or 2500 mg methanol/kg; the two lower doses were administered as a bolus, while the high dose was administered over 1.5 min. A small (approximately 3%) but statistically insignificant (p > 0.1) degree of transpulmonary methanol extraction, expressed as the fractional arterial-venous difference in concentration, was observed after administration of 250 mg methanol/kg. The elimination of methanol from the systemic circulation was markedly nonlinear, suggestive of a significant capacity-limited route of elimination. A single set of kinetic parameters (apparent distributional volume of the central compartment [Vc], intercompartmental transfer rate constants [k12 and k21], and Vmax and Km for elimination) described the blood methanol concentration-time data from rats receiving the 100 and 500 mg/kg doses. Blood methanol concentrations declined much more rapidly in animals receiving the 2500 mg/kg dose than would be predicted from the kinetic parameters derived from the other two experimental groups. The data from the 2500 mg/kg group could be described adequately by a kinetic model incorporating parallel first-order and saturable elimination processes. A portion of this apparent linear elimination pathway was due to renal excretion of the unchanged alcohol. The presence of both linear and nonlinear elimination pathways for methanol may have implications regarding high-dose to low-dose toxicologic extrapolations.
Topics: Animals; Female; Infusions, Intravenous; Kidney; Methanol; Rats; Rats, Sprague-Dawley
PubMed: 8365578
DOI: 10.1006/faat.1993.1078 -
Acta Crystallographica. Section C,... Jun 1997Anthracene-1,8-dimethanol, C16H14O2, crystallized in the centrosymmetric space group P21/n. The anthracene core is nearly planar and shows good agreement with the...
Anthracene-1,8-dimethanol, C16H14O2, crystallized in the centrosymmetric space group P21/n. The anthracene core is nearly planar and shows good agreement with the anthracene core of anthracene-1,8-dicarboxylic acid. The geometric disposition of the hydroxymethyl groups and the values of the hydrogen-bond parameters are strikingly similar to those in the naphthalene analog. As in that structure, each hydroxyl group participates both as a donor and acceptor in an infinite zigzag chain of hydrogen bonds which propagates along the [010] direction. Moreover, the disposition of the entire molecule in the cell of the present compound is also strikingly similar to that of the naphthalene analog in its cell.
Topics: Anthracenes; Chemical Phenomena; Chemistry, Physical; Crystallography, X-Ray; Hydrogen Bonding; Methanol; Models, Molecular; Molecular Structure
PubMed: 9208460
DOI: 10.1107/s0108270197001108 -
Nature Feb 2015The most powerful oxidant found in nature is compound Q, an enzymatic intermediate that oxidizes methane. New spectroscopic data have resolved the long-running...
The most powerful oxidant found in nature is compound Q, an enzymatic intermediate that oxidizes methane. New spectroscopic data have resolved the long-running controversy about Q’s chemical structure.
Topics: Iron Compounds; Methane; Methanol; Oxygenases
PubMed: 25607367
DOI: 10.1038/nature14199 -
JAMA Jun 1975
Topics: Acidosis; Bicarbonates; Humans; Infant; Methanol; Peritoneal Dialysis; Skin Absorption
PubMed: 1173626
DOI: 10.1001/jama.1975.03250090010004 -
The Journal of Physical Chemistry. A Nov 2008To understand the interaction between toluene and methanol, the chemical reactivity of [(C6H5CH3)(CH3OH) n=1-7](+) cluster ions has been investigated via tandem...
To understand the interaction between toluene and methanol, the chemical reactivity of [(C6H5CH3)(CH3OH) n=1-7](+) cluster ions has been investigated via tandem quadrupole mass spectrometry and through calculations. Collision Induced Dissociation (CID) experiments show that the dissociated intracluster proton transfer reaction from the toluene cation to methanol clusters, forming protonated methanol clusters, only occurs for n = 2-4. For n = 5-7, CID spectra reveal that these larger clusters have to sequentially lose methanol monomers until they reach n = 4 to initiate the deprotonation of the toluene cation. Metastable decay data indicate that for n = 3 and n = 4 (CH3OH)3H(+) is the preferred fragment ion. The calculational results reveal that both the gross proton affinity of the methanol subcluster and the structure of the cluster itself play an important role in driving this proton transfer reaction. When n = 3, the cooperative effect of the methanols in the subcluster provides the most important contribution to allow the intracluster proton transfer reaction to occur with little or no energy barrier. As n >or= 4, the methanol subcluster is able to form ring structures to stabilize the cluster structures so that direct proton transfer is not a favored process. The preferred reaction product, the (CH3OH)3H(+) cluster ion, indicates that this size-restricted reaction is driven by both the proton affinity and the enhanced stability of the resulting product.
Topics: Electrons; Mass Spectrometry; Methanol; Protons; Quantum Theory; Toluene
PubMed: 18950147
DOI: 10.1021/jp8041186 -
The British Journal of Ophthalmology Mar 1989
Topics: Animals; Humans; Macaca mulatta; Methanol; Optic Nerve Diseases
PubMed: 2706217
DOI: 10.1136/bjo.73.3.238 -
International Journal of Legal Medicine 1992Four male subjects aged between 20 and 29 years were given intravenous injections of methanol at a dosage of 10 mg per kg body weight, once without prior administration...
Four male subjects aged between 20 and 29 years were given intravenous injections of methanol at a dosage of 10 mg per kg body weight, once without prior administration of ethanol, and once after oral ingestion of 0.3 g ethanol per kg body weight. The serum methanol concentration was monitored over the next 5 h (after methanol administration alone) and 6-7 h (after methanol administration following ethanol ingestion). The elimination of methanol administered alone was found to follow first-order kinetics with a rate constant for the elimination phase of 0.475-0.259 h-1, corresponding to an elimination half-life of 1.8-3.0 h. When ethanol was also administered methanol oxidation was found to be completely blocked until the blood ethanol concentration had fallen to 0.2 g/kg. When the ethanol concentration had dropped to zero, methanol elimination followed exactly the same course as that observed in the experiment without prior administration of ethanol (k: 0.378-0.231 h-1; t1/2: 1.5-2.7 h).
Topics: Adult; Drug Evaluation; Drug Interactions; Ethanol; Forensic Medicine; Humans; Male; Metabolic Clearance Rate; Methanol
PubMed: 1520634
DOI: 10.1007/BF02340834 -
Human & Experimental Toxicology Nov 2001Methanol, a potent toxicant in humans, occurs naturally at a low level in most alcoholic beverages without causing harm. However, illicit drinks made from "industrial...
Methanol, a potent toxicant in humans, occurs naturally at a low level in most alcoholic beverages without causing harm. However, illicit drinks made from "industrial methylated spirits" [5% (v/v) methanol:95% (v/v) ethanol] can cause severe and even fatal illness. Since documentation of a no-adverse-effect level for methanol is nonexistent in the literature a key question, from the public health perspective, is what is the maximum concentration of methanol in an alcoholic drink that an adult human could consume without risking toxicity due to its methanol content? Published information about methanol-intoxicated patients is reviewed and combined with findings in studies in volunteers given small doses of methanol, as well as occupational exposure limits (OELs), to indicate a tolerable ("safe") daily dose of methanol in an adult as 2 g and a toxic dose as 8 g. The simultaneous ingestion of ethanol has no appreciable effect on the proposed "safe" and "toxic" doses when considering exposure over several hours. Thus, assuming that an adult consumes 4 x 25-ml standard measures of a drink containing 40% alcohol by volume over a period of 2 h, the maximum tolerable concentration (MTC) of methanol in such a drink would be 2% (v/v) by volume. However, this value only allows a safety factor of 4 to cover variation in the volume consumed and for the effects of malnutrition (i.e., folate deficiency), ill health and other personal factors (i.e., ethnicity). In contrast, the current EU general limit for naturally occurring methanol of 10 g methanol/l ethanol [which equates to 0.4% (v/v) methanol at 40% alcohol] provides a greater margin of safety.
Topics: Alcoholic Beverages; Humans; Maximum Allowable Concentration; Methanol; Occupational Exposure
PubMed: 11926610
DOI: 10.1191/096032701718620864