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During the key event 1 of skin sensitization defined as covalent binding or haptenization of sensitizer to either thiol or amino group of skin proteins, a sensitizer not only covalently binds with skin proteins but also interacts with nucleophilic small molecules such as glutathione (GSH). Although GSH would not be directly associated with skin sensitization, this interaction may be applied for developing an alternative test method simulating key event 1, haptenization. Thus, the aim of the present study was to examine whether N-acetyl-L-cysteine methyl ester (NACME), a thiol-containing compound, was selected as an electron donor to determine whether NACME reacted with sensitizers. Following a reaction of NACME with a sensitizer in a 96-well plate, the remaining NACME was measured spectrophotometrically using 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB). Following the optimization of test conditions with two different vehicles, such as acetonitrile (ACN) and dimethyl sulfoxide (DMSO), 64 test chemicals were tested to determine the predictive capacity of current NACME test method. The results obtained showed, the predictive capacity of 94.6% sensitivity, 88.9% specificity, and 92.2% accuracy utilizing DMSO as a vehicle with a cutoff NACME depletion of 5.85%. The three parameters were also over 85% in case of ACN. These values were comparable to or better than other OECD-approved test methods. Data demonstrated that a simple thiol-containing compound NACME might constitute as a reliable candidate for identifying reactive skin sensitizers, and that this method be considered as practical method as a screening tool for assessing a chemical's tendency to initiate skin sensitization. [ABSTRACT FROM AUTHOR]

Tetrahydrofuran (THF) purification by distillation is difficult due to the existence of its homogeneous, minimum boiling azeotrope with water. Previously conducted extractive distillation runs were used in this work to validate a rigorous model. The validated model was then used to arrive at a feasible range of operating parameters by performing sensitivity analysis. It is shown through simulations that with the correct operating parameters, use of dimethyl sulfoxide can help obtain almost pure THF. [ABSTRACT FROM AUTHOR]

Our study aimed to investigate the protective role of SDAPR on cisplatin-induced cytotoxicity and its’ possible mechanism in HEK293 cells. Cell viability was measured by MTT assay. Oxidative stress (SOD, GSH, LDH and MDA), inflammatory factors (TNF-α and IL-6) and apoptosis-related proteins (caspase-3, Bax, Bcl-2) expression were measured. The apoptotic cells were observed by TUNEL staining. Our study results indicated that non-cytotoxic levels of SDAPR significantly increased viability rate (LD50 value of cisplatin is 20 μM), which improved antioxidant defence, attenuated apoptosis by decreasing expression levels of cleaved-caspase-3 and Bax, increasing Bcl-2 expression and inhibiting apoptotic positive cells in HEK 293 cells. In addition, SDAPR treatment markedly inhibited the levels of TNF-α and IL-6. In conclusion, Sika deer antler protein, a potential modulator, could alleviate cisplatin-induced cytotoxicity in HEK 293 cells. [ABSTRACT FROM AUTHOR]

Genetic variation is imperative to any plant improvement program. Therefore, this study was primarily based on this aspect of inducing desirable genetic variation for enhancement of the available lentil genetic diversity. The lentil seeds were treated with methyl methanesulfonate (MMS) alone and in combination with dimethyl sulfoxide (DMSO) for inducing polygenic variation as well as determining the impact of DMSO on mutagenecity of MMS. Comparative observations were recorded for bio-physiological damages, morphological variation, and quantitative traits to assess the genetic response of the lentil cultivar L 4076 toward the different concentrations of chemicals. Significant statistics suggested that the DMSO interfere with the extent of mutagenecity of MMS in lentil which could be attributed to either synergistic action of both or variation in MMS uptake. The outcome of mutagenesis on the character association study revealed that mutagenic treatments can modify significantly the manner of association between any two traits in lentil. The moderate doses of MMS in combination with 2% DMSO showed notable diminution in the biological damages while accelerating the rate of desirable high-yielding mutants had proved to be economical. The segregate of the selected mutants in future generations will definitely contribute to the improvement of Lentil genotype. [ABSTRACT FROM AUTHOR]

It is well known that dimethyl sulphoxide (DMSO) increases membrane permeability, which makes it widely used as a vehicle to facilitate drug delivery across biological membranes. However, the mechanism of how DMSO increases membrane permeability has not been well understood. Recently, molecular dynamics simulations have demonstrated that DMSO can induce water pores in biological membranes, but no direct experimental evidence is so far available to prove the simulation result. Using FluxOR Ti+ influx assay and intracellular Ca2+ imaging technique, we studied the effect of DMSO on Ti+ and Ca2+ permeation across cell membranes. Upon application of DMSO on CHO-K1 cell line, Ti+ influx was transiently increased in a dose-dependent manner. The increase in Ti+ permeability induced by DMSO was not changed in the presence of blockers for K+ channel and Na+-K+ ATPase, suggesting that Ti+ permeates through transient water pores induced by DMSO to enter into the cell. In addition, Ca2+ permeability was significantly increased upon application of DMSO, indicating that the transient water pores induced by DMSO were non-selective pores. Furthermore, similar results could be obtained from RAW264.7 macrophage cell line. Therefore, this study provided experimental evidence to support the prediction that DMSO can induce transient water pores in cell membranes, which in turn facilitates the transport of active substances across membranes. [ABSTRACT FROM AUTHOR]

1. The effects of organic solvents, acetonitrile, dimethyl sulfoxide (DMSO), and methanol, which are used to dissolve lipophilic test compounds and cytochrome P450 (P450) substrates, and carried into preincubation at 1% (v/v), on time-dependent inhibition of CYP3A4 by diazepam, were evaluated using human liver microsomes (HLM) and recombinant human P450 expressed microsomes (rCYPs). 2. The inactivation kinetics of CYP3A4 by diazepam dissolved in acetonitrile and methanol were almost equal with kinact/KI values, 0.095 and 0.15 min-1 mM-1 for HLM and 1.1 and 1.4 min-1 mM-1 for rCYP3A4, respectively. In contrast, the inactivation by diazepam dissolved in 1% DMSO significantly decreased and the kinetic parameter could not be calculated. 3. The formation rate of nordiazepam and temazepam metabolized from diazepam dissolved in DMSO were approximately half of those using substrate dissolved in acetonitrile and methanol in both HLM and rCYP3A4. Dixon plots revealed that the metabolism of diazepam in rCYP3A4 were inhibited by DMSO in a competitive or mixed-type manner with Ki (inhibition constant) values of 6 and 24 mM for nordiazepam and temazepam, respectively. 4. In conclusion, the time-dependent inhibition of CYP3A4 by diazepam was attenuated by DMSO, while acetonitrile and methanol had no effect. The metabolite formation profile under the conditions tested suggested that DMSO competitively inhibit the formation of the reactive metabolites of diazepam by CYP3A4. The effect of organic solvents should be taken into consideration when evaluating the in vitro time-dependent inhibition of new chemical entities. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize Huh7 cells' baseline capacity to metabolize drugs and to investigate whether the drug metabolism was enhanced upon treatment with dimethyl sulfoxide (DMSO). The messenger RNA (mRNA) levels of major Phase I and Phase II enzymes were determined by quantitative real-time-polymerase chain reaction (RT-PCR), and activities of major drug-metabolizing enzymes were examined using probe drugs by analysing relevant metabolite production rates. The expression levels of drug-metabolizing enzymes in control Huh7 cells were generally very low, but DMSO treatment dramatically increased the mRNA levels of most drug-metabolizing enzymes as well as other liver-specific proteins. Importantly, functionality assays confirmed concomitant increases in drug-metabolizing enzyme activity. Additionally, treatment of the Huh7 cells with 3-methylcholanthrene induced cytochrome P450 (CYP) 1A1 expression. The results indicate that DMSO treatment of Huh7 cells profoundly enhances their differentiation state, thus improving the usefulness of this common cell line as an in vitro hepatocyte model. [ABSTRACT FROM AUTHOR]

Densities ρ, of the binary systems of dimethyl sulfoxide (DMSO) with methanol, ethanol, propan-1-ol, propan-2-ol, butan-1-ol, and butan-2-ol have been measured as a function of the composition of DMSO at 298.15 K and atmospheric pressure, using an Anton Paar model DMA 4500 oscillating U-tube densitometer. From the experimental results, excess molar volumes [image omitted], and excess partial molar volumes [image omitted], were calculated. Limiting excess partial molar volumes [image omitted], are also calculated by extrapolation of partial excess molar volumes to infinite dilution. The excess molar volumes are negative for methanol, ethanol, propan-1-ol and positive for propan-2-ol, butan-1-ol, and butan-2-ol in the entire composition range. The results are explained in terms of aggregates between unlike molecules through O ··· HO hydrogen bonding. [ABSTRACT FROM AUTHOR]

Dimethyl sulfoxide (DMSO) is extensively used in industry and a large amount of wastewater that contains DMSO is discharged. This investigation evaluates the feasibility and effectiveness of the use of UV, O3 and UV/O3 to degrade aqueous DMSO. DMSO oxidation tests were performed with initial DMSO concentrations of 400-890 mg/L, at various ozone dosages (5.44, 8.25, 12.80 mg/L.min), solution pH values (acidic, alkaline, uncontrolled), and UV irradiation power intensities (0 and 2.25 W/L). Experimental results demonstrated that acidic conditions favored the degradation of DMSO and increased the mass of DMSO decomposition per unit mass of ozone consumption, in both the presence and the absence of UV. DMSO exhibited zero-order degradation kinetics when sufficient ozone was supplied. The cost of the ozone or UV/ozone process per unit volume of wastewater with a DMSO concentration of 2500 mg/L is comparable to that of the UV/H2O2-biological and electrolysis-biological processes described in the literature. [ABSTRACT FROM AUTHOR]

Objectives: To present additional surgical maneuvers that might lead to improved results in the treatment of acute spinal cord injuries (SCI). Methods: Techniques are presented that allow the dura mater to be widely opened over a traumatized spinal cord, thus limiting the opportunity for extrusion of edematous spinal cord material. Additionally, placement of an intact omental pedicle over a traumatized SCI allows absorption of spinal cord edematous fluid. Results: Widely opening the dura mater and placing an intact omental pedicle over an SCI site results in a dynamic equilibrium between the production of spinal cord injury edema fluid and its absorption by the omentum. This absorption of edema fluid allows for the associated absorption of fibrinogen. A decreased fibrinogen level lessens its activation to fibrin, thus resulting in the decreased production of scar tissue which is readily observed in patients with a chronic SCI. Conclusion: A proposal is presented that may have the potential to improve the neurological results following the surgical treatment of an acute SCI. [ABSTRACT FROM AUTHOR]

A single oral dose of 1.25 ml kg -1 of carbon tetrachloride (CCl 4 ) was sufficient to induce significantly elevated levels of serum glutamic pyruvic transaminase (SGPT) and serum glutamic oxaloacetic transaminase (SGOT) together with signs of acute centrilobular necrosis and fatty accumulation in liver tissue. Dimethyl sulfoxide (DMSO) in different dosages (2750 mg kg -1 , 5500 mg kg -1 and 8250 mg kg -1 ; dissolved in saline) were screened for their potential activity against CCl 4 -induced liver injury in Sprague-Dawley rats. The results showed that post-administration of high dosages (5500 mg kg -1 and 8250 mg kg -1 ) of DMSO-saline solution significantly reduced CCl 4 -induced acute elevation in the levels of SGPT and SGOT. The same result was observed in histopathological study of liver tissue. DMSO, in high doses, probably prevented CCl 4 -induced liver injury through its antioxidant, anti-inflammatory or microsomal enzyme arresting properties. [ABSTRACT FROM AUTHOR]