Plasma ethanol

If MDMA is co-administered with ethanol, as 100 mg plus 0.8 g/kg ethanol, plasma concentrations of the former demonstrate a 13% increase compared with MDMA administered alone.21 Plasma concentrations of ethanol decreased 9 to 15% after MDMA administration (n = 9). 

Ma j, Stoter G, Verweij J and Schellens JHM (1996) Comparison of ethanol plasma-protein precipitation with plasma ultrafiltration and trichloroacetic acid protein precipitationfor the measurement of unbound Pt concentrations. Cancer Chemother Pharmacol 38 391-394. 

Factor VIII, immunoglobulin, and albumin are all held as protein precipitates, the first as cryoprecipitate and the others as the Cohn fractions FI + II + III (or FII + III) and FIV + V (or FV), respectively (Table 7, Fig. 2). Similarly, Fractions FIVj + FIV can provide an intermediate product for the preparation of antithrombin III and a-1-proteinase inhibitor. This abiUty to reduce plasma to a number of compact, stable, intermediate products, together with the bacteriacidal properties of cold-ethanol, are the principal reasons these methods are stiU used industrially. 

Facial dushing after ingestion of alcohol occurs in up to one-third of patients taking chlorpropamide. The mechanism, like that of the disulfiram reaction, probably involves inhibition of the oxidation of acetaldehyde, a metaboUte of ethanol. The plasma concentration of chlorpropamide may be correlated with chlorpropamide—alcohol dushing. 

Two colorimetric methods are recommended for boron analysis. One is the curcumin method, where the sample is acidified and evaporated after addition of curcumin reagent. A red product called rosocyanine remains it is dissolved in 95 wt % ethanol and measured photometrically. Nitrate concentrations >20 mg/L interfere with this method. Another colorimetric method is based upon the reaction between boron and carminic acid in concentrated sulfuric acid to form a bluish-red or blue product. Boron concentrations can also be deterrnined by atomic absorption spectroscopy with a nitrous oxide—acetjiene flame or graphite furnace. Atomic emission with an argon plasma source can also be used for boron measurement. 

Zero-order kinetics describe the time course of disappearance of drugs from the plasma, which do not follow an exponential pattern, but are initially linear (i.e. the drug is removed at a constant rate that is independent of its concentration in the plasma). This rare time course of elimination is most often caused by saturation of the elimination processes (e.g. a metabolizing enzyme), which occurs even at low drug concentrations. Ethanol or phenytoin are examples of drugs, which are eliminated in a time-dependent manner which follows a zero-order kinetic. 

An efficient biocatalytic method for the production of amides in multigrara scale has been developed for the synthesis of a pyrrole-amide, which is an intermediate for the synthesis of the dipeptidyl peptidase IV that regulates plasma levels of the insulinotropic proglucagon. CALB catalyzes the ammonolysis of the ester with ammonium carbamate as source of ammonia (Scheme 7.8) [22]. The use of ascarite and calcium chloride as adsorbents for carbon dioxide and ethanol by-products. 

The anion gap is the concentration of plasma anions not routinely measured by laboratory screening. It is useful in the evaluation of acid-base disorders. The anion gap is greater with increased plasma concentrations of endogenous species (e.g., phosphate, sulfate, lactate, and ketoacids) or exogenous species (e.g., salicylate, penicillin, ethylene glycol, ethanol, and methanol). The formulas for calculating the anion gap are as follows ... 

Liver metabolism is affected by methylxanthines. In high doses, theophylline and caffeine increase the level of cyclic AMP. Very high levels of methylxanthines decrease the level of branched chain and aromatic amino acids in plasma. Coffee appears to have little effect on ethanol metabolism. 

Vasopressin is a peptide hormone produced by the hypothalamus and secreted by the posterior pituitary in response to stimulation. Normal stimuli for vasopressin release are hyperosmolarity and hypovolemia, with thresholds for secretion of greater than 280 mOsm/kg and greater than 20% plasma volume depletion. A number of other stimuli, such as pain, nausea, epinephrine, and numerous drugs, induce release of vasopressin. Vasopressin release is inhibited by volume expansion, ethanol, and norepinephrine. The physiological effect of vasopressin is to promote free water clearence by altering the permeability of the renal collecting duct to water. In addition, it has a direct vasoconstrictor effect. Consequently, vasopressin results in water retention and volume restoration. In patients with septic shock, vasopressin is appropriately secreted in response to hypovolemia and to elevated serum osmolarity (R14). 

Mann and Mitchell [58] described a simple colorimetric method for estimation of (-D)-penicillamine in plasma. Blood containing 2-50 pg of penicillamine was mixed with 0.1 M EDTA solution in tromethamine buffer solution. 0.1 mL of this solution was adjusted to pH 7.4 and centrifuged. To a portion of the plasma was added 3 M HCL, the mixture was freeze-dried, and a suspension of the residue in ethanol was centrifuged. The supernatant liquid was mixed with tromethamine buffer solution (pH 8.2) and 10 mM 5,5 -dithiobis-(2-nitrobenzoic acid) in phosphate buffer solution (pH 7.0), the mixture was shaken with ethyl ether, and the absorbance of the separated aqueous layer was measured at 412 nm. The mean recovery was 60% (four determinations), and the calibration graph was linear for the cited range. 

Valproic acid was determined in plasma by treatment with 2,4-dibromoacetophe-none or 2-bromoacetonapththalone and with dicyclohexano-18-crown-6 and heated at 70 °C for 40 min. The solution was subjected to TLC on C8F octyl plates or to high performance TLC on RP 8 254 S or Kieselgel 60 F254 plates with developing solvents of aq. 63% ethanol, aq. 73% ethanol or CHCl3-cyclohexane (2 1), respectively, with detection at 280 or 254 nm for the naphthoylmethyl or phenacyl derivative, respectively. The limits of detection were 9.7 and 4.9 pg/mL of valproic acid for the TLC RP 8 and HPTLC RP 8 plates, respectively. Recovery was 84-92.74% [28],... 

Cohn, E.J. et al. (1947) Preparation and properties of serum and plasma proteins. XIII. Crystallization of serum albumins from ethanol-water mixtures./. Am. Chem. Soc. 69, 1753-1761. 

Partial oxidation is also mentioned as a process to convert ethanol to hydrogen.124 Another novel technology for ethanol to hydrogen has been described by Toci and Modica.125 It is based on cracking ethanol vapors by "cold-plasma-chemical processing" in the presence of a Ni-based catalyst. 

However, the DPPH assay is not suitable for measuring the antioxidant capacity of plasma because protein is precipitated in the presence of the ethanol/methanol solvent used. 

In the PO-CL system, the compounds showing native fluorescence or that fluoresce after chemical derivatization can be detected. As examples of the PO-CL detection of native fluorescence compounds, dipyridamole and benzydamine in rat plasma [57] and fluphenazine [58] have been reported in the former method, the detection limits of dipyridamole and benzydamine were 345 pM and 147 nM in plasma, respectively. Diamino- and aminopyrenes were sensitively determined using TCPO and their detection limits were in the sub-fmol range [59], Carcinogenic compounds such as 1- nitropyrene and its metabolites, can also be determined by the HPLC-PO-CL system. Nonfluorescent nitropyrenes were converted into the corresponding fluorescent aminopyrenes by online reduction on a Zn column followed by detection 2-50-fmol detection limits were achieved in the determination of ethanol extracts from airborne particulates (Fig. 13) [60],... 

Lipid extraction 200 pL of plasma sample is mixed by brief vortexing with 200 pL of ethanol followed 1 min of vortexing with 800 pL hexane. After centrifugation for 5 min at 5000 rpm, 400 pL of upper (hexane) phase is transferred to a glass tube with screwed cap, dried under nitrogen, and kept at - 60°C until PCL analysis. For PCL analysis the sample is dissolved in 400 pL of MeOH by 30 s of vortexing, and 100 pL aliquots are taken for ACL assay. 

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