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Investigation of the Complexation Activity of 2,4-Dithiouracil with Au(III) and Cu(II) and Biological Activity of the Newly Formed Complexes
(2024-08-01) Marinova P.; Stoitsov D.; Burdzhiev N.; Tsoneva S.; Blazheva D.; Slavchev A.; Varbanova E.; Penchev P.
The goal of this study is to synthesize, determine the structure, and examine the antimicrobial properties of novel Cu(II) and Au(III) complexes of 2,4-dithiouracil and its derivatives. These complexes were obtained by mixing aqueous solutions of the corresponding metal salts with the ligand dissolved in DMSO and aqueous NaOH, using a metal-to-ligand ratio of 1:4:2. The structures of the new compounds were analyzed by melting point determination, microwave plasma atomic emission spectrometry (MP-AES) for Cu and Au, inductively coupled plasma optical emission spectrometry (ICP-OES) for S, attenuated total reflection (ATR), solution and solid-state NMR, and Raman spectroscopy. The data for 2,4-dithiouracil obtained from the 1H NMR, 13C NMR, distortionless enhancement by polarization transfer spectrum (DEPT-135), proton–proton homonuclear correlation spectrum (1H-1H COSY), long-range 1H-13C heteronuclear multiple bond correlation experiment (HMBC), and heteronuclear single quantum coherence spectra (HSQC) aided the interpretation of the NMR data for the gold and copper complexes. Furthermore, the antimicrobial effect of the free ligands and their complexes was assessed against Gram-positive and Gram-negative bacteria, as well as yeasts.
Methods and algorithms of optimization in computer engineering: review and comparative analysis Métodos y algoritmos de optimización en ingeniería informática: revisión y análisis comparativo
(2024-02-08) Yakhno V.; Kolumbet V.; Halachev P.; Khambir V.; Ivanenko R.
Introduction: the main areas of application of artificial intelligence for algorithmic analysis and optimization of information flows in tasks of multiparametric diagnostics by means of computer engineering are considered. The issues of globalization of all areas of humanitarian, scientific, technical and engineering activities of human society are considered. It is noted that the common denominator of all directions is information flows. The main tools for their management and algorithmic analysis are multi-parametric methods of artificial intelligence. Method: one of its most relevant areas has been highlighted-the use of evolutionary algorithms in combination with modern diagnostic systems based on computer engineering. The possibility of using intelligent analysis of data from biophysical laser systems in assessing the state of “living matter”-the biological media of the human body-is considered. Results: through algorithmic optimization, a set of new cancer detection markers was determined: the statistical parameters of optical anisotropy maps wavelet coefficients linear distributions-the differences between these markers lie in the range from 4 to 20 times; the asymmetry of the wavelet coefficients autocorrelation function-the differences between these markers lie within two orders of magnitude; for normal state, the wavelet coefficients distributions are multifractal; for prostate cancer, the distributions of the wavelet amplitude coefficients are multifractal. Conclusions: a comparative study of the algorithmic optimization of differences of cancer through the use of multiparametric statistical, correlational, fractal and wavelet analysis of polarization tomograms of optical anisotropy of blood layers of donors and prostate cancer sicks is presented.
Performance of diffusion absorption refrigerators at variable power input
(2024-01-01) Stoyanov Y.; Penkova N.; Krumov K.
Absorption refrigerators have been used in recent decades for utilization of waste or solar energy to produce heat or cold for industrial purposes or to condition the microclimate in buildings. Although these units are designed at nominal power input in the generator, they can also operate at variable parameters of the heat source, which is possible in the real situations. An experimental determination of the operating range and the performance of a diffusion absorption refrigerator at heat pump and refrigeration mode were carried out in the present study. The results are useful for predicting the efficiency and the effectiveness of such systems at variable heat source capacities.
Recent Advances in the Application of Nitro(het)aromatic Compounds for Treating and/or Fluorescent Imaging of Tumor Hypoxia
(2024-08-01) Anichina K.; Lumov N.; Bakov V.; Yancheva D.; Georgiev N.
This review delves into recent advancements in the field of nitro(het)aromatic bioreductive agents tailored for hypoxic environments. These compounds are designed to exploit the low-oxygen conditions typically found in solid tumors, making them promising candidates for targeted cancer therapies. Initially, this review focused on their role as gene-directed enzyme prodrugs, which are inert until activated by specific enzymes within tumor cells. Upon activation, these prodrugs undergo chemical transformations that convert them into potent cytotoxic agents, selectively targeting cancerous tissue while sparing healthy cells. Additionally, this review discusses recent developments in prodrug conjugates containing nitro(het)aromatic moieties, designed to activate under low-oxygen conditions within tumors. This approach enhances their efficacy and specificity in cancer treatment. Furthermore, this review covers innovative research on using nitro(het)aromatic compounds as fluorescent probes for imaging hypoxic tumors. These probes enable non-invasive visualization of low-oxygen regions within tumors, providing valuable insights for the diagnosis, treatment planning, and monitoring of therapeutic responses. We hope this review will inspire researchers to design and synthesize improved compounds for selective cancer treatment and early diagnostics.
Phenotypic characterization and molecular identification of Bacillus pumilus isolated from Algerian goat’s milk and evaluation of its synbiotic effect with Hammada scoparia L. extract and ZnO-NPs
(2024-01-01) Chaima B.; Boutlelis D.A.; Touhami L.A.; Ghemam Amara D.; Khemakhem M.M.; Naccache C.; Atanassova M.; Zahnit W.; Ahmad S.F.; Messaoudi M.
This study was conducted to identify and characterize the Bacillus strain from Goat’s milk in Algeria and to evaluate the prebiotic effect of H. scoparia aqueous extract and ZnO-NPs on the isolated Bacillus strain. Potentially probiotic bacteria were isolated and identified based on phenotypic characteristics, including the morphological, physiological (growth temperature, salt tolerance), biochemical (API 10S strip kits), and confirmed by 16S rDNA gene sequencing. Bacillus pumilus specie of lactic acid bacteria were identified. The base pair length of amplified DNA for the isolate was 1500 Bp. The isolates could not grow at 10°C and 45°C and tolerate up to 6% salt. H. scoparia extract and ZnO-NPs have a beneficial effect on the Bacillus pumilus strain for acid tolerance, bile tolerance, and cell surface hydrophobicity respectively; H. scoparia extract and ZnO-NPs results are high comparing to the control group’s results. As the concentration of the tested samples increases, the percentage of probiotic characteristics of Bacillus pumilus increases, in contrast to the control sample. Therefore, they could be useful tools to define adequate combinations in colonic foods development and health benefits. The beneficial physiological and biochemical properties of isolated Bacillus pumilus space from Goat’s milk with the H. scoparia aqueous extract and ZnO-NPs revealed their potential applications in the food industry.