Primena postupka elektrostatičke ekstruzije pri dobijanju alginatnih čestica malih dimenzija sa imobilisanim ćelijama pivskog kvasca

In beer brewing with immobilized yeast cells it is very important to minimize the mass transfer resistance, problem associated with large diameter beads, because the mass transfer limitations may force the cells to alter their metabolic states and thus, impact the efficiency of fermentation process and quality of final beer. Internal mass transfer can be optimized by adjusting the immobilization matrix size, texture and porosity. The classical dripping method, that is commonly used to produce gel beads, has a limitation in the large diameter of the produced beads, which is typically 2 to 3 mm. In recent time other techniques have been developed to produce smaller particles of equal size. The major objective of this study was to optimize the bead size by using the new technique, electrostatic droplet generation. We have obtained promising results since in this way it was possible to produce very small uniform microbeads (in the diameter range of several hundreds of micrometers to 2 mm) under stable conditions. The size of beads was strongly influenced by applied potential, needle size and electrode distance.Pri primeni imobilisanih ćelija kvasca u fermentaciji piva važno je, kako sa aspekta produktivnosti sistema, tako i sa aspekta hemijskog sastava piva, da se otpori prenosu mase supstrata i proizvoda metabolizma ćelija unutar matrice nosača svedu na najmanju moguću meru. Ovo se može postići podešavanjem veličine, teksture i poroznosti matrice nosača. Obzirom da klasična tehnika imobilizacije kvasca u matrici Ca-alginata daje čestice većih dimenzija (prečnika od 2 do 3 mm), danas je razvijeno vise različitih tehnika koje pružaju mogućnost dobijanja čestica malih dimenzija. Jedna od novih tehnika, čije su mogućnosti primene u cilju optimizacije veličine alginatnih čestica ispitivane u sklopu ovog istraživanja, je postupak elektrostatičke ekstruzije. Dobijeni rezultati su pokazali daje primenom ove tehnike moguće dobiti kontrolisanu i stabilnu proizvodnju mikro čestica uniformne veličine, čiji se prečnik kretao u rasponu od nekoliko stotina mikrometara do 2 mm, u zavisnosti od primenjene razlike potencijala, prečnika igle i rastojanja između elektroda

Association of Vitamin D, Zinc and Selenium Related Genetic Variants With COVID-19 Disease Severity

Background: COVID-19 pandemic has proved to be an unrelenting health threat for more than a year now. The emerging amount of data indicates that vitamin D, zinc and selenium could be important for clinical presentation of COVID-19. Here, we investigated association of genetic variants related to the altered level and bioavailability of vitamin D, zinc and selenium with clinical severity of COVID-19. Methods: We analyzed variants in genes significant for the status of vitamin D (DHCR7/NADSYN1 rs12785878, GC rs2282679, CYP2R1 rs10741657, and VDR rs2228570), zinc (PPCDC rs2120019) and selenium (DMGDH rs17823744) in 120 Serbian adult and pediatric COVID-19 patients using allelic discrimination. Furthermore, we carried out comparative population genetic analysis among European and other worldwide populations to investigate variation in allelic frequencies of selected variants. Results: Study showed that DHCR7/NADSYN rs12785878 and CYP2R1 rs10741657 variants were associated with severe COVID-19 in adults (p = 0.03, p = 0.017, respectively); carriers of DHCR7/NADSYN TG+GG and CYP2R1 GG genotypes had 0.21 and 5.9 the odds for developing severe disease, OR 0.21 (0.05-0.9) and OR 5.9 (1.4-25.2), respectively. There were no associations between selected genetic variants and disease severity in pediatric patients. Comparative population genetic analysis revealed that Serbian population had the lowest frequency of CYP2R1 rs10741657 G allele compared to other non-Finish Europeans (0.58 compared to 0.69 and 0.66 in Spanish and Italian population, respectively), suggesting that other populations should also investigate the relationship of CYP2R1 variant and the COVID-19 disease course. Conclusion: The results of the study indicated that vitamin D related genetic variants were implicated in severe COVID-19 in adults. This could direct prevention strategies based on population specific nutrigenetic profiles

Expression of p63 as predictive and prognostic factor in advanced non-small-cell lung cancer

Background/Aim. Serbia belongs to the group of countries with a high lung cancer incidence and mortality rate. p63 gene plays an important role in development of lung cancer and immunohistochemical expression of p63 is considered to be a reliable marker for squamous histology. The results of some in vitro studies show a significant association of p63 expression and cisplatin chemoresistance. The aim of this study was to estimate the significance of p63 expression as predictive and prognostic factor in advanced non-small-cell lung cancer (NSCLC). Methods. Expression of p63 in 85 NSCLC (stages III, and IV) was investigated by the use of immunohistochemistry. Four weeks after the completion of 2 cycles of platinum-based doublet chemotherapy all the patients were evaluated based on the treatment response. Kaplan-Meier analysis with log-rank tests were used for overall survival (OS) and progression free survival (PFS) calcultations. Results. The expression of p63 was present in 49.4% of the patients out of whom 38.8% were with positive expression (p63+) and 10.6% of the patients were with weak expression (p63+-). Positive expression of p63 was seen in 93.9% of squamous cell carcinomas (SQCC), 5% of adenocarcinomas (AC), and in no patient with not otherwise specified (NOS) NSCLC. Weak expression of p63 was found in 12.5% of AC, 25% of NOS and only in 3% of SQCC. Analysis of the impact of the presence of p63 expression on the initial response to chemotherapy showed no statistical significance. The patients with weak p63 expression had a significantly shorter OS than the patients with no p63 expression (p = 0.049), and the tendency of shorter OS than the patients with p63 expression (p = 0.068). Conclusion. This study shows that p63 expression has no predictive significance for tumor response to initial chemotherapy regimen gemcitabine/ cisplatin or paclitaxel/cisplatin observed in advanced NSCLC. Weak expression of p63 have a negative prognostic effect in stage III and IV NSCLC

Genetic variants in TNFA, LTA, TLR2 and TLR4 genes and risk of sepsis in patients with severe trauma: nested case-control study in a level-1 trauma centre in SERBIA

Introduction: Single nucleotide variants (SNVs) represent important genetic risk factors for susceptibility to posttraumatic sepsis and a potential target for immunotherapy. We aimed to evaluate the association between 8 different SNVs within tumor necrosis factor alpha (TNFA), lymphotoxin alpha (LTA) and Tolllike receptor (TLR2 and TLR4) genes and the risk of posttraumatic sepsis. Methods: Nested case-control study was conducted in the emergency department of the Clinical Centre of Serbia including 228 traumatized patients (44 with sepsis and 184 without sepsis). To compare the results of trauma subjects with the data from the general population, a control group of 101 healthy persons was included in the study. Genotyping of TNFA (rs1800629 and rs361525), LTA (rs909253), TLR2 (rs3804099, rs4696480 and rs3804100), and TLR4 (rs4986790 and rs4986791) was performed for all patients within all three groups using the real-time PCR method. MutationTaster database and in silico software SIFT were used to predict the variant pathogenic effect. Results: Carriage of the G allele of the TNFA rs1800629 gene variant (OR 2.1, 95%CI 1.06-4.16) and T allele-carriage of the TLR4 rs4986791 genetic variant (OR 3.02, 95%CI 1.31-6.57) were associated with significantly higher risk of sepsis in trauma patients when compared to the general population prone to sepsis and traumatized patients without developing a sepsis, respectively. Of these two variants, only variant in TLR4 gene (rs4986791) has been labeled as disease causing by both the MutationTaster database and the in-silico software SIFT, which further supports the role of this variant in various pathologies including sepsis. For the remaining six variants no significant association with the susceptibility to sepsis was detected. Conclusions: Carriage of the G allele of the TNFA rs1800629 gene variant and T allele-carriage of the TLR4 rs4986791 genetic variant confer significant risk of posttraumatic sepsis. TLR4 gene variants (rs4986790 and rs4986791) has been labelled as disease causing

Synthesis and characterization of platinum(IV)-complexes with S-alkyl derivatives of thiosalicylic acid and the crystal structure of the S-butyl derivative of thiosalicylic acid

© 2017, University of Kragujevac, Faculty of Science. All rights reserved. New platinum(IV)-complexes with S-alkyl derivatives of thiosalicylic acid (alkyl = benzyl-(L1), methyl-(L2), ethyl-(L3), propyl-(L4), butyl-(L5)) have been synthesized and characterized by microanalysis, infrared spectroscopy, and1H and13C NMR spectroscopy. The bidentate S,O ligand precursor, the S-butyl derivative of thiosalicylic acid (S-bu-thiosal), was prepared, and its crystal structure was determined. Single crystals suitable for X-ray measurements were obtained by slow crystallization from a DMSO-water system. S-bu-thiosal crystallized in a P21/c space group of a monoclinic crystal system with a = 8.0732 (3) Å, b = 19.6769 (4) Å, c = 8.2291 (3) Å and Z = 4. S-bu-thiosal also has a coplanar geometry

Stereospecific ligands and their complexes. IV: Synthesis, characterization and cytotoxicity of novel platinum(IV) complexes with ethylenediamine-N,N '-di-S,S-2-propanoate and halogenido ligands: Crystal structure of s-cis-[Pt(S,S-eddp)Cl-2]center dot 4H(

The syntheses of two novel platinum(IV) complexes of formula [PtX2(S,S-eddp)center dot nH(2)O (S,S-eddp = ethylenediamine-N,N'-di-S,S-2-propanoate ion, X = chlorido (1) or bromido (2), n = 4, 0) are reported. The complexes have been obtained by direct reaction of corresponding potassium hexahalogenidoplatinate(IV) with neutralized ethylenediamine-N,N'-di-S,S-2-propanoic acid (H-2-S,S-eddp). The complexes were characterized by elemental analysis, infrared, H-1 and C-13 NMR spectroscopy. The spectroscopically predicted geometrical configurations of the obtained complexes were confirmed by X-ray analyses of the crystal structures of the s-cis-[Pt(S,S-eddp)Cl-2]center dot 4H(2)O and uns-cis-[Pt(S,S-eddp)Br-2]. These complexes displayed significantly lower in vitro cytotoxicity in comparison to cisplatin. (c) 2010 Elsevier Ltd. All rights reserved

Synthesis, characterization and cytotoxicity of a new palladium(II) complex with a coumarin-derived ligand. Crystal structure of 4-hydroxy-3-(1-(p-tolylimino)ethyl)-2H-chromen-2-one-palladium(II) complex

The new coumarine derivative, 4-hydroxy-3-(1-(p-tolylimino)ethyl)-2H-chromen-2-one, and corresponding palladium(II) complex have been synthesized and characterized by microanalysis, infrared, H-1 and C-13 NMR spectroscopy. The proposed structure of the complex was confirmed on the basis of an X-ray structural study. In vitro antitumor activity for the ligand and complex was investigated. (C) 2013 Elsevier B.V. All rights reserved.Ministry of Education, Science and Technological Development of the Republic of Serbia [OI172016, OI172021, III41010, III41031]; Research Center of Serbian Academy of Arts and Sciences and the University of Kragujeva

Synthesis, characterization and cytotoxicity of a new palladium(II) complex with a coumarin-derived ligand. Crystal structure of 4-hydroxy-3-(1-(p-tolylimino)ethyl)-2H-chromen-2-one-palladium(II) complex

The new coumarine derivative, 4-hydroxy-3-(1-(p-tolylimino)ethyl)-2H-chromen-2-one, and corresponding palladium(II) complex have been synthesized and characterized by microanalysis, infrared, H-1 and C-13 NMR spectroscopy. The proposed structure of the complex was confirmed on the basis of an X-ray structural study. In vitro antitumor activity for the ligand and complex was investigated. (C) 2013 Elsevier B.V. All rights reserved.Ministry of Education, Science and Technological Development of the Republic of Serbia [OI172016, OI172021, III41010, III41031]; Research Center of Serbian Academy of Arts and Sciences and the University of Kragujeva