Carbon nitride impregnated non-woven jute post-industrial waste in photocatalytic degradation of textile dyes

Textile dye effluents and textile waste disposal represent two significant environmental challenges. Here, we present possible combined solution for both. Urea-derived graphitic carbon nitride g-C3N4 is thermally exfoliated to nano n-C3N4. Both obtained materials are characterized in detail, and their photocatalytic efficacies in photodegradation of three textile azo dyes under simulated solar light irradiation are compared. n-C3N4 exhibited superior performance over g-C3N4 under given experimental conditions. Novelty of the work is the subsequent usage of the non-woven jute post-industrial waste as a photocatalyst support. It was shown that NW jute impregnated with n-C3N4 can be successfully used in three consecutive photocatalytic cycles, keeping high photodegradation efficacy (~ 90% in the case of Acid Orange 7, and 55% in the case of Acid Blue 113). Additionally, possibility of usage of NW jute post-industrial waste as textile dye sorbent is presented in the case of Basic Yellow 28

Microstructure – Properties relationship in laser-welded AZ31B magnesium alloy

The AZ31B magnesium alloy was laser-welded at three different (1.2, 1.6, and 2 kW) laser output powers in the present work. All the butt weld joints are almost defect-free. The size of the weld joint slightly increases with increasing laser output power. The weld metal is formed by columnar grains of the alpha phase at the weld metal/base metal interface, but a finely equiaxed grain microstructure is formed in the centres of fusion zones. The minor phases are Mg17Al12 and (Al,Mg)8Mn5. The weld metal microstructure manifests clear refinement with a decrease in laser output power. Microstructural changes are reflected in changes in mechanical properties; weld joints prepared at the lowest laser output power manifest the highest microhardness, ultimate tensile strength, yield strength, and almost 90% joint efficiency. This is related to the different extents of strengthening mechanisms that act most effectively in weld joints made at 1.2 kW laser output power. Detail analysis of fracture surfaces confirmed that lower laser output power and general microstructural refinement favours the formation of plastically deformed material, which is in excellent agreement with both the experimentally determined and the calculated values of yield strength

Targeting Alzheimer’s Disease: Evaluating the Efficacy of C-1 Functionalized N-Aryl-Tetrahydroisoquinolines as Cholinergic Enzyme Inhibitors and Promising Therapeutic Candidates

We have synthesized 22 C-1 functionalized-N-aryl-1,2,3,4-tetrahydroisoquinoline derivatives showing biological activities towards cholinergic enzymes. Synthesis was performed using visible-light-promoted photo-redox chemistry, starting from a common intermediate, and the application of this synthetic methodology drastically simplified synthetic routes and purification of desired compounds. All synthesized derivates were divided into four groups based on the substituents in the C-1 position, and their inhibition potencies towards two cholinergic enzymes, acetyl- and butyrylcholinesterase were evaluated. Most potent derivatives were selected, and kinetic analysis was further carried out to obtain insights into the mechanisms of inhibition of these two enzymes. Further validation of the mode of inhibition of cholinergic enzymes by the two most potent THIQ compounds, 3c and 3i, was performed using fluorescence-quenching titration studies. Molecular docking studies further confirmed the proposed mechanism of enzymes’ inhibition. In silico predictions of physicochemical properties, pharmacokinetics, drug-likeness, and medicinal chemistry friendliness of the selected most potent derivatives were performed using Swiss ADME tool. This was followed by UPLC-assisted log P determination and in vitro BBB permeability studies performed in order to assess the potential of the synthesized compounds to pass the BBB

The effect of sintering temperature on cavitation erosion in glass–ceramics based on coal fly ash

The incombustible portion of coal that remains after burning is known as bottom or fly ash, and it has a detrimental influence on the environment. One of the possible alternatives for reducing the amount of ash deposited in landfills might be the production of useful glass–ceramic from vitrified fly ash. Glass–ceramic was synthesized using fly ash from the thermal power plant "Nikola Tesla" and fluxing additives. Sinter crystallization of the parent glass resulted in glass ceramics. The glass was created by melting a combination of coal fly ash (CFA), Na2CO3, and CaCO3 at T = 1500 °C and quenching the melt in the air. Glass powders were sintered at temperatures 850 and 900 °C. The resulting glass–ceramics were characterized microstructurally, physically, and mechanically. The cavitation erosion of samples was evaluated. The cavitation rate was 0.015 mg/min for the sample sintered at 850 °C and 0.0053 mg/min for the sample sintered at 900 °C. The leaching of heavy metals in glass–ceramic samples was determined using Toxicity Characteristic Leaching Procedure. A low concentration of heavy metals in the leaching solution showed that heavy metals were successfully incorporated in the glass matrix and that obtained glass–ceramics are ecologically safe for usage. Both samples exhibit good resistance to cavitation erosion, suggesting their potential as possible replacements for structural ceramics commonly employed components of hydraulic machinery

Expression levels of GSDMB and ORMDL3 are associated with relapsing-remitting multiple sclerosis and IKZF3 rs12946510 variant

Multiple sclerosis (MS), a noncurable autoimmune neurodegenerative disease, requires constant research that could improve understanding of both environmental and genetic factors that lead to its occurrence and/or progression. Recognition of the genetic basis of MS further leads to an investigation of the regulatory role of genetic variants on gene expression. Among risk variants for MS, Ikaros zinc finger 3 (IKZF3) gene variant rs12946510 was identified as one of the top-ranked and the expression quantitative trait loci (eQTL) for genes residing in chromosomal locus 17q12- 21. The study aimed to investigate the association of gene expression of the immunologically relevant genes, which map to indicated locus, ORMDL3, GSDMB, and IKZF3, with MS and rs12946510 genotype, taking into account disease phase, clinical parameters of disease progression, and severity and immunomodulatory therapy. We used TaqMan® technology for both allelic discrimination and gene expression determination in 67 relapsing MS patients and 50 healthy controls. Decreased ORMDL3 and GSDMB mRNA levels had significant associations with MS and rs12946510 TT rare homozygote among patients. Significant positive correlations between ORMDL3 and GSDMB mRNA expression were observed in both patients and controls. We detected the significant between-effect of sex and rs12946510 on the expression of ORMDL3 in the patient group and interferon β therapy and rs12946510 on GSDMB expression. Our results show the association of ORMDL3 and GSDMB mRNA expression with the clinical manifestation of MS and confirm that IKZF3 rs12946510 exerts the eQTL effect on both genes in multiple sclerosis. Besides providing novel insight related to MS phases and interferon β therapy, the study results confirm previous studies on regulatory genetic variants, autoimmunity, and MS

Vanadium compounds: New potential antidiabetic drugs

Glavni ciljevi u lečenju osoba sa dijabetesom su ostvarenje individualnih glikemijskih ciljeva i prevencija komplikacija. Današnja savremena terapija dijabetesa, uz izuzetne uspehe, ima i određena ograničenja kao što su: paranteralni put primene leka, smanjenje efikasnosti leka nakon početnog poboljšanja glikemije, nedostupnost novijih lekova u nerazvijenim zemljama ili nepristupačnost leka zbog visoke cene. Zbog toga postoji stalna potreba za razvojem antihipeglikemijskih lekova jeftinijih i lakših za primenu, sa većom efikasnošću i manje toksičnim. U tom cilju, znatan broj studija ispitivao je uticaj neorganskih i organskih jedinjenja vanadijuma u snižavanju vrednosti hiperglikemije. Pokazano je da neorganska jedinjenja vanadijuma nakon peroralne primene imaju jako nizak stepen apsorpcije, tako da su visoke doze u snižavanju hiperglikemije izazivale ozbiljne neželjene efekte kod ispitanika. S druge strane, organsko jedinjenje vanadijuma bis(etilmaltolat)oksovanadijum(IV) došlo je do faze 2 kliničke studije ispitivanja antidijabetičke efikasnosti i bezbednosti, ali je studija prekinuta zbog nefrotoksičnog neželjenog efekta. Poslednjih nekoliko godina velika pažnja je posvećena istraživanju antidijabetičke aktivnosti polioksovanadata, ali su podaci o toksičnom potencijalu ovih jedinjenja još uvek nedovoljni. Iako je antidijabetička aktivnost odavno dokazana, tačni mehanizmi dejstva jedinjenja vanadijuma još uvek nisu u potpunosti razjašnjeni. U literaturi se navodi da jedinjenja vanadijuma mogu delovati na: sekreciju insulina, osetljivost ciljnih tkiva na insulin, stvaranje glukoze u jetri ili obim apsorpcije glukoze u digestivnom traktu. U zaključku, uprkos obećavajućim rezultatima dobijenim u istraživanjima na životinjama i ljudima, za sada još uvek nije otkriveno jedinjenje vanadijuma delotvorno u snižavanju hiperglikemije, uz istovremeno prihvatljivu bezbednost i sigurnost. Zbog toga je u budućnosti potrebno ulagati u pronalaženje novih jedinjenja vanadijuma, čije koristi će biti veće u odnosu na rizike.The general goals of diabetes treatment are to maintain optimal individualized glycemic targets and to prevent complications. Today, there are significant barriers to successful diabetes therapy, such as parenteral drug administration, decreased therapeutic efficacy after an initial improvement in glycemia, inaccessibility of new medicines in lower-income countries, and high drug prices. Accordingly, significant research attention has been devoted to the development of a cheap and comfortable antidiabetic agent, which demonstrates success in lowering blood glucose levels as well as fewer toxicity properties. In recent years, the effects of inorganic and organic vanadium compounds have been investigated in diabetes treatment. These studies have found the low bioavailability of orally administered inorganic vanadium salts; thus, effective doses to reduce blood glucose levels to normal may cause serious adverse events. In addition, the only study with an organo-vanadium compound (bis(maltolato)oxovanadium(IV)), which has reached Phase IIa clinical trial, was terminated after three months due to renal complications. Moreover, despite a growing interest in polyoxovanadates for treating diabetes in the last few years, the toxic potentials of these compounds are still unknown. However, the precise mechanism of their antidiabetic actions remains unclear. A broad spectrum of possible mechanisms and hypotheses, such as enhancement of insulin secretion and enhanced sensitivity to insulin, as well as suppression of hepatic glucose production and decrease of intestinal glucose absorption, have been presented. In conclusion, besides the promising results obtained in animal and human studies, no vanadium compound has successfully reduced blood glucose with acceptable safety and tolerability. More studies of vanadium benefit-risk could lead to a new era in vanadium biomedicine

Sequence variability of HCV core region and host genetic and epigenetic factors can predict the response to combined PEG-IFN/RBV therapy in patients with chronic hepatitis c infection genotype 1B

Variations in the hepatitis C virus (HCV) core gene are related to the progression of liver fibrosis and therapy response. However, the influence of individual amino acid (aa) substitutions at different positions of HCV Core protein on the response to combined pegylated interferon/ribavirin (PEG-IFN/RBV) therapy and disease progression is not yet fully understood. The HCV Core protein can inactivate various genes in the host genome by affecting the methylation of their promoters, leading to liver damage and carcinogenesis. Two genes whose methylation status is affected by the HCV Core protein are the tumor suppressor genes RASSF1A and p16. We have previously shown that the methylation status of these two genes, together with the single nucleotide polymorphism (SNP) rs12979860 near the interleukin-28 beta subunit (IL-28B) gene, influences the response to combined therapy. Herein, we investigated a possible association between detected aa substitutions in HCV Core protein and response to combined therapy, liver disease progression, IL28B genotype, and the methylation status of the RASSF1A and p16 genes. In 29 examined patients we found no association between individual aa substitutions and therapy response. However, we observed that patients with HCV Core aa substitutions at position 75 and CT/TT IL28B genotypes were non-responders (NR) (p=0.023), which was associated with the presence of unmethylated RASSF1A gene. In contrast, even 75% of patients with aa substitutions at position 91 and CC IL28B genotype achieved a sustained virologic response (SVR) (p=0.030), and 70% of them had methylated RASSF1A gene. There was no significant association between the methylation status of the p16 gene and aa variations in the HCV core region. Our results suggest that combined analysis of aa substitutions in HCV Core protein, IL28B genotype, and methylation status of the RASSF1A gene may help predict response to PEG-IFN/RBV therapy in patients with chronic hepatitis C genotype 1b.xx2nd B&H Symposium of Laboratory Geneticists and Molecular Biologists (with International Participation) : Book of abstracts : 10-11 May, 2024

Application of neural network to study of frequency range effect to photoacoustic measurement of thermoelastic properties of thin aluminum samples

In this paper, the influence of the measurement range on the prediction of thermoelastic and geometric properties of a thin aluminum sample obtained by solving the inverse photoacoustic problem using neural networks was analyzed. Tests of neural networks on theoretical photoacoustic signals showed that the accuracy of solving the inverse problem increases with the increase of the measurement range, which is in accordance with the theory of solving inverse problems. Tests on experimentally measured signals in a transmission experimental setup with an open photoacoustic cell, from which the influence of the transmission characteristic of the detector was removed, show the advantages of using narrow frequency bands. This result indicates the need for further investigations of both: the influence of the measuring chain on the recorded signal and the influence of additional processes and sample properties on the thermoelastic behavior of thin metal films

Velocity Map Imaging Photoelectron Spectroscopy of Silver Iodide Aerosol Particles

The valence band electronic structure of isolated silveriodide nanoparticles (AgI NP) was investigated by vacuum-ultravioletaerosol photoelectron spectroscopy using the velocity map imagingtechnique (VUV VMI-PES). The VUV VMI-PES results were obtainedfor polydisperse aerosol produced by aggregation of hydrocolloid ofsilver iodide particles 8 - 15 nm in size. The ionization energy of theAgI particles was found to be 6.0 ± 0.1 eV with respect to the vacuumlevel. The DFT calculations showed that the main contribution to thedensity of AgI electronic states in the valence region originates from I5p orbitals. The dependence of the asymmetry parameter on theelectron energy showed that the value of the characteristic energyloss of excited photoelectrons was 2.7 eV, which coincided with theband gap of the nanomaterial.Peer-reviewed manuscript: [https://vinar.vin.bg.ac.rs/handle/123456789/13365

Cobalt-ferrite nano-cubes for magnetic hyperthermia applications

Highly crystalline superparamagnetic nano-cubes of CoFe2O4 with size of about 15 nm were prepared by the thermal decomposition method. The structure, morphology, magnetic properties, magnetothermal response, and cytotoxicity study were used to investigate the CoFe2O4 nano-cubes for magnetic hyperthermia. Diffraction methods (employing X-ray and transition electron microscope) confirm the presence of an inverted spinel structure of cobalt ferrite. The presence of a spin-disordered magnetically dead layer that has been confirmed both by X-ray diffraction and magnetometry data. The average crystallite size DXRD ∼ 12 nm has been found smaller than the average physical edge of the nano-cube observed by transition electron microscope DTEM ∼ 15 nm. The analysis of the isothermal magnetization data by assuming a cubic instead of spherical shape of the prepared nanoparticles yielded conclusive values of relevant parameters. The effective magnetocrystalline anisotropy constant K = 2.3×105 J/m3 determined by the Law of approach and by the fitting of coercivity data is in excellent correspondence with collected zero-field cooled magnetization data for nano-cube system of crystallite size ∼ 12 nm. In-vitro cytotoxicity tests on U87MG (cancer model) and HDF (non-cancer models) confirm the good biocompatibility and very low cytotoxicity. One of the our mail contributions is, that we provide exact analysis of relaxation processes responsible for heat generation in our nano-cube system and we obtained higher SAR and IPL coefficients than 30 commercial iron-oxide nanoparticle systems designed for magnetic hyperthermia. This, along with the promising results of the magneto-thermal response, indicates the suitability of using the prepared nano-cubes for applications in magnetic particle hyperthermia