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The article discusses the issues of analyzing objects of handwriting examination provided in electronic form. The authors describe the ways of obtaining such manuscripts and their features determined by the type of the electronic documents submitted for examination. They also provide some information on the possibility of establishing if the manuscript was made using the handwriting input option, the specifics of such objects, and their differences from digitized manuscripts. The peculiarities of the stage of separate research of manuscripts presented in electronic files are outlined, as well as the problems of formulating conclusions are addressed. Finally, the authors determine the directions for further scientific research on the matters raised.

A procedure is proposed for the extraction of 2,6-diisobornyl-4-methylphenol (IBP), the molecule with potential multi-target activity, and its active metabolite 2,6-diisobornyl-4-hydroxymethylphenol (IBP-OH) from human and rat plasma samples for further determination by liquid chromatography-tandem mass spectrometry. The solubility of IBP (in mg/mL) in various organic solvents is determined. In particular, the compound is readily soluble in chloroform (346 ± 14), methyl tert-butyl ether (98.6 ± 3.8), and ethyl acetate (96.8 ± 2.0). It is shown that the use of a mixture of chloroform and isopropanol (5 : 1, v/v) as an extraction system with simultaneous protein precipitation makes it possible to extract only 66 ± 10% of IBP, while the recovery of IBP-OH is 96 ± 7%. Pre-dilution of 200 [micro]L of plasma with 300 [micro]L saline increases IBP recovery to 100 ± 4%. Drying the extracts in a vacuum concentrator (air, 45°C) with the further reconstitution of the residues in 300 [mu]L of acetonitrile facilitates the purification of biosamples and the preconcentration of analytes. The total sample preparation time does not exceed 70 min, and the duration of an analysis is 7 min, the injection volume is 2 [micro]L. The procedure has been successfully tested on actual rat plasma samples after a single oral administration of IBP (10 mg/kg in oil) in the framework of pharmacokinetic studies., Author(s): A. P. Lakeev [sup.1] [sup.2] , E. A. Yanovskaya [sup.1] [sup.2] , V. A. Yanovsky [sup.1] , M. O. Andropov [sup.1] Author Affiliations: (1) grid.77602.34, 0000 0001 1088 3909, [...]

A procedure for the determination of dexketoprofen trometamol in human plasma by liquid chromatography-mass spectrometry (HPLC-MS/MS) using ibuprofen as an internal standard was proposed and validated. The matrix effect on the analyte response value was estimated; its short-term and long-term stability in a biological matrix and an aqueous acetonitrile solution was investigated. In addition, the stability of the analyte after freezing and thawing of samples was studied. It was shown that the dilution of samples by one half does not affect the accuracy and precision of the analysis. The limit of detection and the lower limit of quantification were 0.01 [micro]g/mL; the linearity range was 0.01-8.50 [micro]g/mL (R.sup.2 = 0.9974); the total analysis time was 3.5 min. Intra- and interday accuracy values were in the ranges 96.66-100.00% and 94.97-97.92%, respectively. Sample preparation, including liquid-liquid extraction with ethyl acetate in an acidic medium, is simple and fast. The developed procedure was successfully tested on real plasma samples from healthy volunteers in the framework of a comparative study of the pharmacokinetics and bioequivalence of a generic drug., Author(s): A. P. Lakeev [sup.1] [sup.2], E. A. Yanovskaya [sup.1], O. S. Bryushinina [sup.1], Yu. G. Zyuz'kova [sup.1], G. A. Frelikh [sup.1], N. Yu. Abdrashitova [sup.1], V. V. Udut [sup.1] [...]

The dose proportionality and bioavailability of the potential anti-inflammatory and neuroprotective JNK inhibitor 11H-indeno[1,2-b]quinoxalin-11-one oxime (IQ-1) were evaluated by comparing pharmacokinetic parameters after single oral (25, 50 and 100 mg/kg) and intravenous (1 mg/kg) IQ-1 administration in rats. IQ-1 and its major metabolite ketone 11H-indeno[1,2-b]quinoxalin-11-one (IQ-18) were isolated from plasma samples by liquid–liquid extraction. IQ-1 (E-isomer) and IQ-18 were simultaneously quantified in plasma by the validated method of liquid chromatography with triple quadrupole mass spectrometry (HPLC–MS/MS). The absolute bioavailability of IQ-1 was < 1.5%. Cmax values were 24.72 ± 4.30, 25.66 ± 7.11 and 37.61 ± 3.53 ng/mL after single oral administration of IQ-1 at doses of 25, 50 and 100 mg/kg, respectively. IQ-1 exhibited dose proportionality at 50–100 mg/kg dose levels, whereas its pharmacokinetics was not dose proportional over the range of 25–50 mg/kg. IQ-18 demonstrated the invariance of the dose-normalized Cmax. In this study we systematically elucidated the absorption characteristics of IQ-1 in rat gastrointestinal tract and provided better understanding of IQ-1 pharmacology for the future development of a new formulations and therapeutic optimisation. [ABSTRACT FROM AUTHOR]

Barbituric acids are a useful tool for the construction of various supramolecular compounds with intriguing physicochemical properties. Also, barbiturates play a significant role in biology and medicine. The same is true for imidazole derivatives. Herein, three novel salts of barbituric (H2BA) and 2-thiobarbituric (H2TBA) acids with imidazole (Im), namely imidazolium barbiturate in two polymorphic modifications, HIm(HBA) (1) (pale yellow) and (2) (pale orange), and imidazolium 2-thiobarbiturate, HIm(HTBA) (3), were synthesized and characterized by CHNS elemental analysis, single-crystal and powder X-ray diffraction, FT-IR and UV-Vis spectroscopy techniques. Crystal structure analysis revealed that the compounds feature three different supramolecular architectures with the formula unit count (Z′) varying from 1 for 3 to 4 for 1, which is governed by an unusual geometry of hydrogen bonding motifs. Intermolecular interactions in crystals 1–3 were analyzed using 2D-fingerprint plots derived from the Hirshfeld surfaces. According to the TG-DSC analysis, compounds 1–3 were thermally stable up to ∼100 °C in air. The solubility studies (solubility product constants and solubility at a fixed pH value were determined) showed that salts 2 and 3 were more soluble in water than H2(T)BA. To the best of our knowledge, this is one of the first reports on the phenomenon of polymorphism among organic salts with barbiturate moieties. Thus, the present findings broaden our understanding of the supramolecular organization of barbiturates, complement the systematic studies of the correlation between their crystal structure and physicochemical properties and lay the foundation for the further development of novel materials based on imidazolium (2-thio)barbiturates. [ABSTRACT FROM AUTHOR]

Aim. Controlled treatment of the physico-chemical and mechanical properties of a three-dimensional crosslinked matrix based on reactive chitosan. Materials and methods. The three-dimensional matrices were obtained using photosensitive composition based on allyl chitosan (5 wt%), poly(ethylene glycol) diacrylate (8 wt%) and the photoinitiator Irgacure 2959 (1 wt%) by laser stereolithography setting. The kinetic swelling curves were constructed for structures in the base and salt forms of chitosan using gravimetric method and the contact angles were measured using droplet spreading. The supercritical fl uid setting (40 °C, 12 MPa) was used to process matrices during 1.5 hours. Using nanohardness Piuma Nanoindenter we calculated values of Young’s modulus. The study of cytotoxicity was performed by direct contact with the culture of the NIH 3T3 mouse fi broblast cell line. Results. Architectonics of matrices fully repeats the program model. Matrices are uniform throughout and retain their shape after being transferred to the base form. Matrices compressed by 5% after treatment in supercritical carbon dioxide (scCO2 ). The elastic modulus of matrices after scCO2 treatment is 4 times higher than the original matrix. The kinetic swelling curves have similar form. In this case the maximum degree of swelling for matrices in base form is 2–2.5 times greater than that of matrices in salt form. There was a surface hydrophobization after the material was transferred to the base form: the contact angle is 94°, and for the salt form it is 66°. The basic form absorbs liquid approximately 1.6 times faster. The fi lm thickness was increased in the area of contact with the liquid droplets after absorption by 133 and 87% for the base and the salt forms, respectively. Treatment of samples in scCO2 reduces their cytotoxicity from 2 degree of reaction (initial samples) down to 1 degree of reaction. Conclusion. The use of supercritical carbon dioxide for scaffolds allows improving biocompatibility of the applied material for 1 degree and increasing the elastic modulus of the material more than 3 times. Allyl chitosan forms stable three-dimensional networks during laser photopolymerization. This enables desorbing toxic low molecular weight component without destruction of the matrix structure.

The role of urban areas in the global land-use structure is permanently growing. Urban ecosystems differ principally from natural ones in formation conditions, driving factors and functioning. Green areas play a key role in city structure, performing important environmental, ornamental and health functions. The methodology widely accepted so far for the environmental control of urban green zones is not able to consider multiple functions of urban areas as well as their unique spatial variability. Herewith we propose a new approach for functional-environmental monitoring of urban green zones in Moscow city, including not only static, but also dynamic parameters and considering their spatial variability and profile distribution. The proposed approach was tested for the case of six green areas within the Sadovoe Ring, Central administrative district of the Moscow city. It was demonstrated that the proposed methodology was much more informative than conventional ones and also better support taking optimal decisions in the sphere of maintaining environmental quality of urban ecosystems.

There is still lack of clear information on the urban soils mainly because of their extremely high spatial variability. In this study we analyzed the specific features of urban soils’ spatial variability at the local level (64 ha plot; 126 sampling points). Four contrast urban soil sub-types were distinguished in the study area: primitive urban soils on the technogenic parent material, grey-humus soils with urbopedogenensis features, urbanozems and urban soil on the layers of sewage accumulation. Comparison between the results of regional and local analysis did not show the trend of spatial variability decrease as a result of detailed elaboration. Thus it may be concluded that high spatial variability is an integral feature of urban soils, that assumes principally different approach for their spatial analysis.

Indole‐3‐carbinol is the subject of ongoing biomedical research owing to its potential antiatherogenic, anticarcinogenic and antioxidant effects. The antitumor properties are mainly associated with its major metabolite, i.e. 3,3′‐diindolylmethane (DIM). Typically, the biological activity of the chemical compound is manifested in the ng/ml concentration range. Consequently, the development of highly sensitive analytical methods to determine DIM in various biological samples is an urgent issue. In this study, an HPLC–MS/MS method was established for the quantification of DIM in human plasma. The developed method was validated according to the European Medicines Agency guidelines. Sensitivity, selectivity, accuracy and precision were good, allowing DIM quantification in the concentration range of 5–500 ng/ml. The limit of detection and the lower limit of quantification were 1 and 5 ng/ml, respectively. 4‐Methoxy‐1‐methylindole was used as an internal standard (IS). The analytes were extracted from the human plasma by the acetonitrile‐induced protein precipitation method with the addition of 3 mol/L ammonium sulfate as a salting‐out agent, which is a facile and efficient approach for high‐throughput bioanalysis. The chromatographic separation was performed on the Synergi Fusion‐RP C18 column (50 × 2.0 mm, 4 μm, 80 Å) under isocratic elution at 40°C. The mobile phase consisting of acetonitrile and water (0.1% formic acid; 85:15, v/v) was delivered at a flow rate of 0.20 ml/min. DIM and the IS were eluted at 2.36 ± 0.04 and 2.43 ± 0.03 min, respectively. The total analysis time was 3.20 min. Atmospheric pressure chemical ionization was carried out using multiple reaction monitoring in the positive polarity mode. The ion transitions were set to m/z 247.1 → 130.1 (DIM) and 162.1 → 147.1 (IS). The method was successfully applied to the analysis of plasma samples after a single oral administration of the Indinol® Forto drug (200 mg) to healthy female Russian volunteers. Also, the developed method was used for the analysis of rabbit plasma samples after a single oral dose of DIM (20 mg/kg). [ABSTRACT FROM AUTHOR]