91 research outputs found

    Investigating the in vitro Antitumor Structure-activity Relationship of a Range of Cannabinolic Acid Derivatives

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    Aim: To investigate the in vitro structure-activity relationship (SAR) of a range of tetrahydrocannabinolic (THCA) and cannabidiolic (CBDA) derivatives using the PANC-1 tumor cell line (pancreas, ductal carcinoma). Materials and methods: The in vitro effects of a range of THCA and CBDA derivatives with different carbonyl group substituents were tested on the PANC-1 cells cell line using the CellTiter Glo Viability Assay (72 hours) and the XTT assay (48 hours). Results: A study of a series of THCA and CBDA derivatives containing different functional groups at the carbonyl nitrogen atom demonstrated that THCA amides have better inhibitory activity, on the PANC-1 tumor cell line, than CBDA derivatives. Conclusions: THCA derivatives have better inhibitory activity than CBDA analogs with the same substituents. It is noteworthy that even a slight change in the structure of the substituent of the amide or hydrazone moiety of the molecule has a dramatic effect on the activity of these compounds

    In vitro Activity of Novel Cannabinoids Derived from Tetrahydrocannabinolic Acid on Various Human Tumor Cell Lines

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    The in vitro study of tetracannabinolic acid (THCA) derivatives ALAM027 and ALAM108 was carried out on the following human tumor cells: T47D (breast, ductal carcinoma), PC-3 (prostate, adenocarcinoma), HT29 (colorectal carcinoma), Caco-2 (colon, adenocarcinoma), A549 (lung, carcinoma), U87MG (human glioblastoma) and U266B1 (multiple myeloma). The in vitro effects of THCA derivatives ALAM027 and ALAM108 on cell growth inhibition and IC50 values were measured using the CellTiter Glo assay. The ALAM027 compound showed good growth inhibition in all cell lines tested with the exception of U87MG cells. The ALAM108 compound also suppressed the growth of U87 MG cells but had little effect on T47D tumor cells. In vitro studies of THCA derivatives ALAM027 and ALAM108 showed antitumor activity in all cell lines tested. The difference in the activity of these compounds in relation to the T47D and U87MG tumor cells may be indicative of different functional mechanisms

    Numerical simulation of subsurface defect identification by pulsed thermography and improvement of this technique for noisy data

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    Pulsed thermography is an active non-destructive technique which uses optical excitation source to stimulate heating of the object under investigation. This work is devoted to the simulation of the pulsed thermography method in a steel plate with the ceramic coating containing artificial defects of various depths and sizes. The simulation has been carried out on the base of the model which takes into account complex heat exchange of the sample with the surrounding by convection, conduction and radiation. Comparison of the temperature contrast with the experimental data has shown that the results are in a good qualitative and quantitative agreement in all stages of the cooling process. Due to the fact that the temperature contrast is often susceptible to the surface noise of various nature the Kalman-based signal processing technique was developed. The comparative analysis has shown that the proposed filtration technique provides better value of signal-to-noise ratio in comparison to the considered well-known techniques of signal reconstruction when proper calibration of the filtration parameters is carried ou

    Numerical simulation of a heat generation in a layered material during ultrasonic wave propagation

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    Ultrasonic vibrothermography is an effective and non-destructive method, which can be used for a quick detection of coating defects on large surfaces. Mechanical excitation of a layered structure induces inelastic deformation and, as a consequence, energy dissipation in the defective area and local heating. In this work, a three-dimensional numerical simulation of this process is applied to the bi-metallic layered structure with an edge crack. Two models of energy dissipation are considered (hysteretic damping model and visco-elastic Maxwell’s model) for simulation of energy dissipation in a crack tip area under ultrasonic loading. The models allow us to study the effects of the loading frequency, loading direction and location of the coating defects on the heat dissipation and propose optimal regimes for the ultrasonic vibrothermography of bi-metallic layered structures

    Properties of CrSi2 Layers Obtained by Rapid Heat Treatment of Cr Film on Silicon

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    The changes in the morphology and the electrophysical properties of the Cr/n-Si (111) structure depending on the rapid thermal treatment were considered in this study. The chromium films of about 30 nm thickness were deposited via magnetron sputtering. The rapid thermal treatment was performed by the irradiation of the substrate’s back side with the incoherent light flux of the quartz halogen lamps in nitrogen medium up to 200–550 ◦C. The surface morphology was investigated, including the grain size, the roughness parameters and the specific surface energy using atomic force microscopy. The resistivity value of the chromium films on silicon was determined by means of the four-probe method. It was established that at the temperatures of the rapid thermal treatment up to 350◦C one can observe re-crystallization of the chromium films with preservation of the fine grain morphology of the surface, accompanied by a reduction in the grain sizes, specific surface energy and the value of specific resistivity. At the temperatures of the rapid thermal treatment from 400 to 550◦C there originates the diffusion synthesis of the chromium disilicide CrSi2 with the wave-like surface morphology, followed by an increase in the grain sizes, roughness parameters, the specific surface energy and the specific resistivity value
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