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1.
Front Immunol ; 15: 1358478, 2024.
Article in English | MEDLINE | ID: mdl-38698840

ABSTRACT

Introduction: Cancer combination treatments involving immunotherapies with targeted radiation therapy are at the forefront of treating cancers. However, dosing and scheduling of these therapies pose a challenge. Mathematical models provide a unique way of optimizing these therapies. Methods: Using a preclinical model of multiple myeloma as an example, we demonstrate the capability of a mathematical model to combine these therapies to achieve maximum response, defined as delay in tumor growth. Data from mice studies with targeted radionuclide therapy (TRT) and chimeric antigen receptor (CAR)-T cell monotherapies and combinations with different intervals between them was used to calibrate mathematical model parameters. The dependence of progression-free survival (PFS), overall survival (OS), and the time to minimum tumor burden on dosing and scheduling was evaluated. Different dosing and scheduling schemes were evaluated to maximize the PFS and optimize timings of TRT and CAR-T cell therapies. Results: Therapy intervals that were too close or too far apart are shown to be detrimental to the therapeutic efficacy, as TRT too close to CAR-T cell therapy results in radiation related CAR-T cell killing while the therapies being too far apart result in tumor regrowth, negatively impacting tumor control and survival. We show that splitting a dose of TRT or CAR-T cells when administered in combination is advantageous only if the first therapy delivered can produce a significant benefit as a monotherapy. Discussion: Mathematical models are crucial tools for optimizing the delivery of cancer combination therapy regimens with application along the lines of achieving cure, maximizing survival or minimizing toxicity.


Subject(s)
Immunotherapy, Adoptive , Receptors, Chimeric Antigen , Animals , Immunotherapy, Adoptive/methods , Mice , Combined Modality Therapy/methods , Receptors, Chimeric Antigen/immunology , Humans , Multiple Myeloma/therapy , Multiple Myeloma/immunology , Multiple Myeloma/radiotherapy , Models, Theoretical , Cell Line, Tumor , Neoplasms/therapy , Neoplasms/immunology , Neoplasms/radiotherapy , Radioisotopes/therapeutic use , T-Lymphocytes/immunology , Xenograft Model Antitumor Assays
2.
Int J Mol Sci ; 24(14)2023 Jul 22.
Article in English | MEDLINE | ID: mdl-37511566

ABSTRACT

The efficacy of antitumor radiotherapy can be enhanced by utilizing nonradioactive nanoparticles that emit secondary radiation when activated by a primary beam. They consist of small volumes of a radiosensitizing substance embedded within a polymer layer, which is coated with tumor-specific antibodies. The efficiency of nanosensitizers relies on their successful delivery to the tumor, which depends on their size. Increasing their size leads to a higher concentration of active substance; however, it hinders the penetration of nanosensitizers through tumor capillaries, slows down their movement through the tissue, and accelerates their clearance. In this study, we present a mathematical model of tumor growth and radiotherapy with the use of intravenously administered tumor-specific nanosensitizers. Our findings indicate that their optimal size for achieving maximum tumor radiosensitization following a single injection of their fixed total volume depends on the permeability of the tumor capillaries. Considering physiologically plausible spectra of capillary pore radii, with a nanoparticle polymer layer width of 7 nm, the optimal radius of nanoparticles falls within the range of 13-17 nm. The upper value is attained when considering an extreme spectrum of capillary pores.


Subject(s)
Nanoparticles , Neoplasms , Humans , Models, Theoretical , Neoplasms/radiotherapy , Neoplasms/blood supply , Polymers
3.
Dalton Trans ; 52(25): 8601-8612, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37282978

ABSTRACT

In contrast to V(V) complexes with various organic ligands, a simple vanadate without any additive is inactive in neutral medium toward the oxidation of alkanes with H2O2. In this work, we discovered that the insufficient activation of H2O2 upon coordination to the simple vanadate - the commonly accepted reason for the low catalytic activity of the vanadate - cannot explain this phenomenon. Two main findings are reported here on the basis of DFT calculations. First, the generally accepted Fenton-like mechanism of the generation of the active oxidizing species (HO˙) in a vanadate/H2O2(aq)/MeCN system was revisited. A new mechanism based on the tremendous activation of the OOH ligand in the intermediate [V(OO)2(OOH)(H2O)] toward the homolytic O-O bond cleavage is not only feasible but significantly more favourable than the Fenton-like pathway. The surprisingly low activation barrier calculated for the HO˙ generation (15.4 kcal mol-1) demonstrates the efficiency of this process. The presence of easily oxidizable non-innocent OO ligands in this intermediate explains such an activation. Second, it was found that the generated HO˙ radicals may be easily captured by the V atom soon after their formation followed by the elimination of the molecular oxygen. This side reaction of the H2O2 dismutation efficiently consumes the produced HO˙ radicals decreasing their concentration in the reaction mixture and preventing the following oxidation of alkanes.

4.
J Theor Biol ; 558: 111371, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36462667

ABSTRACT

A spatially-distributed continuous mathematical model of solid tumor growth and treatment by fractionated radiotherapy is presented. The model explicitly accounts for the factors, widely referred to as 4 R's of radiobiology, which influence the efficacy of radiotherapy fractionation protocols: tumor cell repopulation, their redistribution in cell cycle, reoxygenation and repair of sublethal damage of both tumor and normal tissues. With the use of special algorithm the fractionation protocols that provide increased tumor control probability, compared to standard clinical protocol, are found for various physiologically-based values of model parameters under the constraints of fixed overall normal tissue damage and maximum admissible fractional dose. In particular, it is shown that significant gain in treatment efficacy can be achieved for tumors of low malignancy by the use of protracted hyperfractionated protocols. The optimized non-uniform protocols are characterized by gradual escalation of fractional doses in their last parts, which start after the levels of oxygen and nutrients significantly elevate throughout the tumor and accelerated tumor proliferation manifests itself, which is a well-known experimental phenomenon.


Subject(s)
Neoplasms , Radiobiology , Humans , Dose Fractionation, Radiation , Neoplasms/pathology , Cell Division , Models, Theoretical
5.
Sensors (Basel) ; 22(22)2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36433199

ABSTRACT

Accurate information about growing crops allows for regulating the internal stocks of agricultural products and drawing strategies for negotiating agricultural commodities on financial markets. Machine learning methods are widely implemented for crop type recognition and classification based on satellite images. However, field classification is complicated by class imbalance and aggregation of pixel-wise into field-wise forecasting. We propose here a Bayesian methodology for the aggregation of classification results. We report the comparison of class balancing techniques. We also report the comparison of classical machine learning methods and the U-Net convolutional neural network for classifying crops using a single satellite image. The best result for single-satellite-image crop classification was achieved with an overall accuracy of 77.4% and a Macro F1-score of 0.66. Bayesian aggregation for field-wise classification improved the result obtained using majority voting aggregation by 1.5%. We demonstrate here that the Bayesian aggregation approach outperforms the majority voting and averaging strategy in overall accuracy for the single-image crop classification task.


Subject(s)
Agriculture , Crops, Agricultural , Bayes Theorem , Machine Learning , Neural Networks, Computer
6.
Int Angiol ; 41(5): 405-412, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36264097

ABSTRACT

BACKGROUND: This study aimed to assess the efficacy and safety of Actovegin for the treatment of patients with Fontaine stage IIB peripheral arterial disease (PAD). METHODS: The study included 366 patients with Fontaine stage IIB PAD from 19 centers (Russia, Georgia, Kazakhstan). Placebo or Actovegin (1200 mg daily [QD]) were administered intravenously for two weeks, followed by a 10-week course of oral administration (placebo or Actovegin 1200 mg QD). The primary efficacy outcome was percentage change in the initial claudication distance (ICD) by week 12. Secondary outcomes included percent and absolute changes in ICD, absolute claudication distance (ACD) and changes in Quality of Life (QoL) assessed by the SF-36 Mental Health Score. RESULTS: The increase in ICD after 12 weeks of Actovegin treatment was 29.19% (LS mean [Actovegin vs. placebo]; 95% CI: 9.35-49.02; P=0.0041). The percentage increase in ICD at 24 weeks was 35.51% (LS mean; 95% CI: 10.96-60.05; P=0.0047), which correspond to an increase in absolute ICD of 41.22 m (LS mean; 95% CI: 16.77-65.66; P=0.0010). The percentage increase in ACD after 24 weeks was 36.47% compared with the baseline (LS mean; 95% CI: 10.07-62.88; P=0.0069), which corresponded to an absolute increase in ACD of 50.92 m (LS mean; 95% CI: 18.35-83.49; P=0.0023). A statistically significant improvement in QoL with Actovegin compared with placebo was demonstrated within 24 weeks (LS mean 2.28; 95% CI: 0.88-3.68; P=0.0015). Actovegin demonstrated an acceptable safety and tolerability profile with minor differences from placebo. CONCLUSIONS: The results of this 12-week course of Actovegin demonstrated its superiority over placebo in the increase in ICD and ACD at weeks 2, 12 and 24 from the start of treatment. Actovegin has an acceptable safety and tolerability profile.


Subject(s)
Intermittent Claudication , Peripheral Vascular Diseases , Humans , Heme/therapeutic use , Intermittent Claudication/diagnosis , Intermittent Claudication/drug therapy , Quality of Life , Walking
7.
Dalton Trans ; 51(34): 13071-13084, 2022 Aug 30.
Article in English | MEDLINE | ID: mdl-35972307

ABSTRACT

In this work, four new ruthenium complexes [Ru(η6-p-cymene)(L1)Cl] 1, [Ru(η6-p-cymene)(L2)Cl] 2, [Ru(η6-p-cymene)(L3)Cl] 3 and [Ru(η6-p-cymene)(L4)Cl] 4 [HL1 = (2-cyanophenyl)glycine; HL2 = (5-chloro-2-cyanophenyl)glycine; HL3 = (2-cyano-3-fluorophenyl)glycine; HL4 = (4-cyanophenyl)glycine] were synthesized and well characterized by several spectroscopic and analytical techniques. Complexes 1 and 3 were found to be fluorescent in most of the solvents; however, 2 and 4 were found to be fluorescent mostly in EtOAc, DMF and ethanol. Amongst these four complexes, 3 has shown selective sensing against CO32- and SO42- anions by quenching of fluorescence. The LOD values are found to be in the sub-micromolar range. Investigations of the sensing mechanism performed by computation and NMR studies indicate a possible adduct formation between the NH group of the ligand and the anion(s) through hydrogen bond formation, which ultimately might lead to proton transfer to the bi-negative anion. The quantum yield of the complex 3 was found to decrease on addition of CO32- and SO42- anions from 0.46 to 0.13 and 0.12, respectively. The Job's plot indicates the binding between the probe and anion in a 1 : 1 ratio for both CO32- and SO42- anions. Along with that, all the complexes were found to be biocompatible when tested against several cell lines showing very high IC50 values. It can also be observed that 1 is capable of penetrating within the cells and can act as a cell imaging agent showing fluorescence, and thus can be used for bio-imaging purposes.


Subject(s)
Antineoplastic Agents , Coordination Complexes , Ruthenium , Anions , Antineoplastic Agents/chemistry , Cell Line, Tumor , Coordination Complexes/chemistry , Glycine , Ligands , Magnetic Resonance Spectroscopy , Ruthenium/chemistry
8.
Inorg Chem ; 61(23): 8670-8684, 2022 Jun 13.
Article in English | MEDLINE | ID: mdl-35650511

ABSTRACT

Imidoylamidinate-based heteroleptic bis(2-phenylbenzothiazole)iridium(III) and -rhodium(III) complexes [(bt)2M(N∩N)] (bt = 2-phenylbenzothiazole, N∩N = N'-(benzo[d]thiazol-2-yl)acetimidamidyl (Ir1 and Rh1), N'-(6-fluorobenzo[d]thiazol-2-yl)acetimidamidyl (Ir2), N'-(benzo[d]oxazol-2-yl)acetimidamidyl (Ir3), N'-(1-methyl-1H-benzo[d]imidazol-2-yl)acetimidamidyl (Ir4); yields 70-84%) were obtained by the reaction of the in situ-generated solvento-complex [(bt)2M(NCMe)2]NO3 and benzo[d]thia/oxa/N-methylimidozol-2-amines in the presence of NaOMe. Complexes Ir1-4 exhibited intense orange photoluminescence, reaching 37% at room temperature quantum yields, being immobilized in a poly(methyl methacrylate) matrix. A photophysical study of these species in a CH2Cl2 solution, neat powder, and frozen (77 K) MeOC2H4OH-EtOH glass matrix─along with density-functional theory (DFT), ab initio methods, and spin-orbit coupling time-dependent DFT calculations─verified the effects of substitution in the imidoylamidinate ligands on the excited-state properties. Electrochemical (cyclic voltammetry and differential pulse voltammetry) and theoretical DFT studies demonstrated noninnocent behavior of the imidoylamidinate ligands in Ir1-4 and Rh1 complexes due to the significant contribution coming from these ligands in the HOMO of the complexes. The iridium(III) species exhibit a ligand (L, 2-phenylbenzothiazole)-centered (3LC), metal-to-ligand (L', imidoylamidinate) charge-transfer (3ML'CT,3MLCT) character of their emission. The imidoylamidinate-based iridium(III) species were proved to be effective as the emissive dopant in an organic light-emitting diode device, fabricated in the framework of this study.

9.
Molecules ; 27(9)2022 Apr 20.
Article in English | MEDLINE | ID: mdl-35566013

ABSTRACT

Ternary potassium-iron sulfide, KFeS2, belongs to the family of highly anisotropic quasi-one-dimensional antiferromagnets with unusual "anti-Curie-Weiss" susceptibility, quasi-linearly growing with a rising temperature up to 700 K, an almost vanishing magnetic contribution to the specific heat, drastically reduced magnetic moment, etc. While some of the measurements can be satisfactorily described, the deficiency of the entropy changes upon the magnetic transition and the spin state of the iron ion remains a challenge for the further understanding of magnetism. In this work, high-quality single-crystalline samples of KFeS2 were grown by the Bridgman method, and their stoichiometry, crystal structure, and absence of alien magnetic phases were checked, utilizing wave-length dispersive X-ray electron-probe microanalysis, powder X-ray diffraction, and 57Fe Mössbauer spectroscopy, respectively. An ab initio approach was developed to calculate the thermodynamic properties of KFeS2. The element-specific phonon modes and their density of states (PDOS) were calculated applying the density functional theory in the DFT + U version, which explicitly takes into account the on-site Coulomb repulsion U of electrons and their exchange interaction J. The necessary calibration of the frequency scale was carried out by comparison with the experimental iron PDOS derived from the inelastic nuclear scattering experiment. The infrared absorption measurements confirmed the presence of two high-frequency peaks consistent with the calculated PDOS. The calibrated PDOS allowed the calculation of the lattice contribution to the specific heat of KFeS2 by direct summation over the phonon modes without approximations and adjustable parameters. The temperature-dependent magnetic specific heat evaluated by subtraction of the calculated phonon contribution from the experimental specific heat provides a lower boundary for estimating the reduced spin state of the iron ion.

10.
Phys Rev E ; 105(1-1): 014209, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35193238

ABSTRACT

Over the past few decades, formation of Turing patterns in reaction-diffusion systems has been shown to be the underlying process in several examples of biological morphogenesis, confirming Alan Turing's hypothesis, put forward in 1952. However, theoretical studies suggest that Turing patterns formation via classical "short-range activation and long-range inhibition" concept in general can happen within only narrow parameter ranges. This feature seemingly contradicts the accuracy and reproducibility of biological morphogenesis given the stochasticity of biochemical processes and the influence of environmental perturbations. Moreover, it represents a major hurdle to synthetic engineering of Turing patterns. In this work it is shown that this problem can be overcome in some systems under certain sets of interactions between their elements, one of which is immobile and therefore corresponding to a cell-autonomous factor. In such systems Turing patterns formation can be guaranteed by a simple universal control under any values of kinetic parameters and diffusion coefficients of mobile elements. This concept is illustrated by analysis and simulations of a specific three-component system, characterized in absence of diffusion by a presence of codimension two pitchfork-Hopf bifurcation.

11.
Dalton Trans ; 51(3): 1019-1031, 2022 Jan 17.
Article in English | MEDLINE | ID: mdl-34935834

ABSTRACT

A solvothermal reaction of Cd(II) with the dicarboxyl-functionalized arylhydrazone pro-ligands, 5-(2-(2,4,6-trioxotetrahydro-pyrimidin-5(2H)-ylidene)hydrazineyl)isophthalic acid (H5L1) and 5-(2-(2,4-dioxopentan-3-ylidene)hydrazineyl)isophthalic acid (H3L2), or their halogen bond donor centre(s) decorated analogs 2,4,6-triiodo-5-(2-(2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)hydrazineyl)isophthalic acid (H5L3) and 5-(2-(2,4-dioxopentan-3-ylidene)hydrazineyl)-2,4,6-triiodoisophthalic acid (H3L4), leads to the formation of known [Cd(H3L1)(H2O)2]n (1) and new {[Cd(HL2)(H2O)2(DMF)]·H2O}n (2), [Cd(H3L3)]n (3) and {[Cd2(µ-H2O)2(µ-H2L4)2(H2L4)2]·2H2O}n (4) coordination compounds, respectively. The aggregation of mononuclear units via Cd-OC and Cd-OH2 coordination and CAr-I⋯I types of intramolecular halogen bonds lead to a dinuclear tecton 4. Both CAr-I⋯O and CAr-I⋯I types of intermolecular halogen bonds play a fundamental role in the supramolecular architectures of the obtained metal-organic frameworks 3 and 4. Theoretical (DFT) calculations confirmed the presence of the CAr-I⋯O and CAr-I⋯I halogen bonds in 3 and 4 and allowed their characterisation. The formation of intermolecular noncovalent interactions between the attached iodine substituents to the hydrazone ligands and polar solvent (water or methanol) molecules promoted, at least in part, the solubility of the corresponding complexes (3 and 4), which act as homogeneous catalyst precursors in the Henry reaction between aldehydes and nitroethane. The corresponding ß-nitroalkanol products were obtained in good yields (66-79%) and with good diastereoselectivity (threo/erythro ca. 72 : 28) in water at room temperature.

12.
Lasers Surg Med ; 54(4): 611-622, 2022 04.
Article in English | MEDLINE | ID: mdl-34918347

ABSTRACT

OBJECTIVES: The development of compact diagnostic probes and instruments with an ability to direct access to organs and tissues and integration of these instruments into surgical workflows is an important task of modern physics and medicine. The need for such tools is essential for surgical oncology, where intraoperative visualization and demarcation of tumor margins define further prognosis and survival of patients. In this paper, the possible solution for this intraoperative imaging problem is proposed and its feasibility to detect tumorous tissue is studied experimentally. METHODS: For this aim, the sapphire scalpel was developed and fabricated using the edge-defined film-fed growth technique aided by mechanical grinding, polishing, and chemical sharpening of the cutting edge. It possesses optical transparency, mechanical strength, chemical inertness, and thermal resistance alongside the presence of the as-grown hollow capillary channels in its volume for accommodating optical fibers. The rounding of the cutting edge exceeds the same for metal scalpels and can be as small as 110 nm. Thanks to these features, sapphire scalpel combines tissue dissection with light delivering and optical diagnosis. The feasibility for the tumor margin detection was studied, including both gelatin-based tissue phantoms and ex vivo freshly excised specimens of the basal cell carcinoma from humans and the glioma model 101.8 from rats. These tumors are commonly diagnosed either non-invasively or intraoperatively using different modalities of fluorescence spectroscopy and imaging, which makes them ideal candidates for our feasibility test. For this purpose, fiber-based spectroscopic measurements of the backscattered laser radiation and the fluorescence signals were carried out in the visible range. RESULTS: Experimental studies show the feasibility of the proposed sapphire scalpel to provide a 2-mm-resolution of the tumor margins' detection, along with an ability to distinguish the tumor invasion region, which results from analysis of the backscattered optical fields and the endogenous or exogenous fluorescence data. CONCLUSIONS: Our findings justified a strong potential of the sapphire scalpel for surgical oncology. However, further research and engineering efforts are required to optimize the sapphire scalpel geometry and the optical diagnosis protocols to meet the requirements of oncosurgery, including diagnosis and resection of neoplasms with different localizations and nosologies.


Subject(s)
Aluminum Oxide , Neoplasms , Animals , Humans , Lasers , Margins of Excision , Optical Fibers , Phantoms, Imaging , Rats
13.
J Am Chem Soc ; 143(38): 15701-15710, 2021 Sep 29.
Article in English | MEDLINE | ID: mdl-34529411

ABSTRACT

Platinum(II) complexes exhibiting an expressed dz2-nucleophilicity of the positively charged metal centers, namely, [Pt(ppy)(acac)] (1; acacH is acetylacetone; ppyH is 2-Ph-pyridine) and [Pt(ppy)(tmhd)] (2; tmhdH is 2,2,6,6-tetramethylheptanedione-3,5), were cocrystallized with the chalcogen bond donors (4-NC5F4)2Ch (Ch = Se, Te) to form two isostructural cocrystals 1·1/2(4-NC5F4)2Ch, and 2·2/3(4-NC5F4)2Se and 2·(4-NC5F4)2Te. The X-ray data for these cocrystals and appropriate theoretical DFT calculations (PBE0-D3BJ) allowed the recognition of the metal-involving chalcogen bond, namely, Ch···dz2-PtII (its energy spans from -7 to -12 kcal/mol). In 1·1/2(4-NC5F4)2Ch, Ch···dz2-PtII bonding is accompanied by the C···dz2-PtII interaction, representing a three-center bifurcate, whereas in 2·(4-NC5F4)2Te the chalcogen bond Te···dz2-PtII is purely two-centered and is stronger than that in 1·1/2(4-NC5F4)2Ch because of more efficient orbital overlap. The association of 2 with (4-NC5F4)2Te and the structure of the formed adduct in CDCl3 solutions was studied by using 1H, 13C, 19F, 195Pt, 125Te NMR, 19F-1H HOESY, and diffusion NMR methods. The 195Pt and 125Te NMR titration and the isothermal titration calorimetry results revealed a 1:1 association of 2 with (4-NC5F4)2Te.

14.
Molecules ; 26(18)2021 Sep 21.
Article in English | MEDLINE | ID: mdl-34577180

ABSTRACT

The 3-Iodo-1-nitrosonaphthalene-2-ol (I-NON) was obtained by the copper(II)-mediated iodination of 1-nitroso-2-naphthol (NON). The suitable reactants and optimized reaction conditions, providing 94% NMR yield of I-NON, included the usage of Cu(OAc)2·H2O and 1:2:8 CuII/NON/I2 molar ratio between the reactants. The obtained I-NON was characterized by elemental analyses (C, H, N), high-resolution ESI+-MS, 1H and 13C{1H} NMR, FTIR, UV-vis spectroscopy, TGA, and X-ray crystallography (XRD). The copper(II) complexes bearing deprotonated I-NON were prepared as follows: cis-[Cu(I-NON-H)(I-NON)](I3) (1) was obtained by the reaction between Cu(NON-H)2 and I2 in CHCl3/MeOH, while trans-[Cu(I-NON-H)2] (2) was synthesized from I-NON and Cu(OAc)2 in MeOH. Crystals of trans-[Cu(I-NON-H)2(THF)2] (3) and trans-[Cu(I-NON-H)2(Py)2] (4) were precipitated from solutions of 2 in CHCl3/THF and Py/CHCl3/MeOH mixtures, respectively. The structures of 1 and 3-4 were additionally verified by X-ray crystallography. The characteristic feature of the structures of 1 and 3 is the presence of intermolecular halogen bonds with the involvement of the iodine center of the metal-bound deprotonated I-NON. The nature of the I···I and I···O contacts in the structures of 1 and 3, correspondingly, were studied theoretically at the DFT (PBE0-D3BJ) level using the QTAIM, ESP, ELF, NBO, and IGM methods.

15.
Molecules ; 26(7)2021 Apr 05.
Article in English | MEDLINE | ID: mdl-33916483

ABSTRACT

Bond energy is the main characteristic of chemical bonds in general and of non-covalent interactions in particular. Simple methods of express estimates of the interaction energy, Eint, using relationships between Eint and a property which is easily accessible from experiment is of great importance for the characterization of non-covalent interactions. In this work, practically important relationships between Eint and electron density, its Laplacian, curvature, potential, kinetic, and total energy densities at the bond critical point as well as bond length were derived for the structures of the [Z-I···Hal]- and [Z-Hal···I]- types bearing halogen bonds and involving iodine as interacting atom(s) (totally 412 structures). The mean absolute deviations for the correlations found were 2.06-4.76 kcal/mol.

16.
Dalton Trans ; 50(10): 3701-3716, 2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33634805

ABSTRACT

Two new benzimidazole Schiff base copper(ii) compounds [Cu(5-CH2PPh3-2-salmethylben)(NO3)(H2O)][BF4]·2/3(H2O)·1/3(MeOH) (1) and [Cu(5-CH2NEt3-2-salmethylben)(Cl)][BF4] (2) were synthesised by mixing 2-(1-methyl-1H-benzo[d]imidazol-2-yl)aniline, (3-formyl-4-hydroxybenzyl)triphenylphosphonium chloride or N,N-diethyl-N-(3-formyl-4-hydroxybenzyl)ethanaminium chloride and Cu(NO3)2·3H2O or CuCl2·2H2O in the presence of tetrafluoroborate in a binary mixture of MeOH : H2O under refluxing conditions. The structures of the compounds were established by elemental analysis, FT-IR, ESI-MS analytical techniques and, for 1, by single-crystal X-ray diffraction analysis. Absorption and fluorescence spectroscopic methods were performed to evaluate the calf thymus DNA interactions with the compounds. The calculated binding constants (Kb) of 3.14 × 105 M-1 for 1 and 3.20 × 105 M-1 for 2 were established. The intercalative DNA binding mode was also verified by molecular docking studies. Both compounds demonstrated a notable in vitro cytotoxic effect against human A-549 (lung carcinoma), MCF-7 (breast cancer) and HeLa (cervical cancer) cancer cell lines. A substantial repressive effect on the proliferation of MCF-7 cells (breast cancer cells) was observed for compound 1. The mechanism of action for the effective antiproliferative activity of 1 has additionally been confirmed by means of various biological studies such as morphological assessment through AO/EB, detection of apoptotic induction via Hoechst/PI dual staining, flow cytometry for detection of cell cycle arrest, quantitative analysis of apoptotic cells, DNA degradation, generation of reactive oxygen species (ROS) and by apoptotic induction through mitochondrial staining.


Subject(s)
Antineoplastic Agents/pharmacology , Benzimidazoles/pharmacology , Breast Neoplasms/drug therapy , Coordination Complexes/pharmacology , Copper/pharmacology , DNA/drug effects , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Benzimidazoles/chemistry , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cattle , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Copper/chemistry , Crystallography, X-Ray , DNA/chemistry , DNA/metabolism , Density Functional Theory , Drug Screening Assays, Antitumor , Estrogens/metabolism , Female , Humans , Molecular Docking Simulation , Schiff Bases/chemistry , Schiff Bases/pharmacology
17.
Neural Regen Res ; 16(3): 550-560, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32985487

ABSTRACT

Despite emerging contemporary biotechnological methods such as gene- and stem cell-based therapy, there are no clinically established therapeutic strategies for neural regeneration after spinal cord injury. Our previous studies have demonstrated that transplantation of genetically engineered human umbilical cord blood mononuclear cells producing three recombinant therapeutic molecules, including vascular endothelial growth factor (VEGF), glial cell-line derived neurotrophic factor (GDNF), and neural cell adhesion molecule (NCAM) can improve morpho-functional recovery of injured spinal cord in rats and mini-pigs. To investigate the efficacy of human umbilical cord blood mononuclear cells-mediated triple-gene therapy combined with epidural electrical stimulation in the treatment of spinal cord injury, in this study, rats with moderate spinal cord contusion injury were intrathecally infused with human umbilical cord blood mononuclear cells expressing recombinant genes VEGF165, GDNF, NCAM1 at 4 hours after spinal cord injury. Three days after injury, epidural stimulations were given simultaneously above the lesion site at C5 (to stimulate the cervical network related to forelimb functions) and below the lesion site at L2 (to activate the central pattern generators) every other day for 4 weeks. Rats subjected to the combined treatment showed a limited functional improvement of the knee joint, high preservation of muscle fiber area in tibialis anterior muscle and increased H/M ratio in gastrocnemius muscle 30 days after spinal cord injury. However, beneficial cellular outcomes such as reduced apoptosis and increased sparing of the gray and white matters, and enhanced expression of heat shock and synaptic proteins were found in rats with spinal cord injury subjected to the combined epidural electrical stimulation with gene therapy. This study presents the first proof of principle study of combination of the multisite epidural electrical stimulation with ex vivo triple gene therapy (VEGF, GDNF and NCAM) for treatment of spinal cord injury in rat models. The animal protocols were approved by the Kazan State Medical University Animal Care and Use Committee (approval No. 2.20.02.18) on February 20, 2018.

18.
Chemistry ; 26(65): 14833-14837, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-32567710

ABSTRACT

Intramolecular chalcogen bonding in arylhydrazones of sulfamethizole is strengthened by conjugation in the π-system of a noncovalent five-membered ring. The S⋅⋅⋅O distance in the sulfamethizole moiety of these compounds ranges from 2.698(3) to 2.806(15) Å, which indicates its strong dependence on the attached arylhydrazone fragments. Information on the nature of the intramolecular chalcogen bond was afforded by DFT calculations.


Subject(s)
Chalcogens/chemistry , Coloring Agents , Vibration
19.
Molecules ; 25(11)2020 Jun 06.
Article in English | MEDLINE | ID: mdl-32517273

ABSTRACT

The mononuclear zinc(II) complex cis-[ZnL2(H2O)2] (1; L = 4-(pyridin-3-ylcarbamoyl)benzoate) was synthesized and characterized. By soaking crystals of 1 in a mixture of DMF-H2O solution containing a slight excess of Cu(NO3)2 × 3H2O a transmetalation reaction occurred affording the related copper(II) complex trans-[CuL2(H2O)2] (2). The structures of the compounds were authenticated by single crystal X-ray diffraction revealing, apart from a change in the isomerism, an alteration in the relative orientation of the chelating carboxylate groups and of the pyridine moieties. H-bond interactions stabilize both geometries and expand them into two-dimensional (2D) networks. The transmetalation was confirmed by SEM-EDS analysis. Moreover, the thermodynamic feasibility of the transmetalation is demonstrated by density-functional theory (DFT) studies. The catalytic activities of 1 and 2 for the oxidation of styrene and for the nitroaldol (Henry) C-C coupling reaction were investigated. The copper(II) compound 2 acts as heterogeneous catalyst for the microwave-assisted oxidation of styrene with aqueous hydrogen peroxide, yielding selectively (>99%) benzaldehyde up to 66% of conversion and with a turnover frequency (TOF) of 132 h-1. The zinc(II) complex 1 is the most active catalyst (up to 87% yield) towards the nitroaldol (Henry) coupling reaction between benzaldehyde and nitro-methane or -ethane to afford the corresponding ß-nitro alcohols. The reaction of benzaldehyde with nitroethane in the presence of 1 produced 2-nitro-1-phenylpropanol in the syn and the anti diastereoisomeric forms, with a considerable higher selectivity towards the former (66:34).


Subject(s)
Amides/chemistry , Chelating Agents/chemistry , Copper/chemistry , Heterocyclic Compounds, 3-Ring/chemistry , Nitro Compounds/chemistry , Styrene/chemistry , Zinc/chemistry , Catalysis , Models, Molecular , Oxidation-Reduction
20.
Chaos ; 30(3): 033106, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32237770

ABSTRACT

The classical concept for emergence of Turing patterns in reaction-diffusion systems requires that a system should be composed of complementary subsystems, one of which is unstable and diffuses sufficiently slowly while the other one is stable and diffuses sufficiently rapidly. In this work, the phenomena of emergence of Turing patterns are studied and do not fit into this concept, yielding the following results. (1) The criteria are derived, under which a reaction-diffusion system with immobile species should spontaneously produce Turing patterns under any diffusion coefficients of its mobile species. It is shown for such systems that under certain sets of types of interactions between their species, Turing patterns should be produced under any parameter values, at least provided that the corresponding spatially non-distributed system is stable. (2) It is demonstrated that in a reaction-diffusion system, which contains more than two species and is stable in absence of diffusion, the presence of a sufficiently slowly diffusing unstable subsystem is already sufficient for diffusion instability (i.e., Turing or wave instability), while its complementary subsystem can also be unstable. (3) It is shown that the presence of an immobile unstable subsystem, which leads to destabilization of waves within an infinite range of wavenumbers, in a spatially discrete case can result in the generation of large-scale stationary or oscillatory patterns. (4) It is demonstrated that under the presence of subcritical Turing and supercritical wave bifurcations, the interaction of two diffusion instabilities can result in the spontaneous formation of Turing structures outside the region of Turing instability.

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