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Status esencijalnih elemenata u uzorcima seruma pacijenata obolelih od multipla skleroze
No full textCilj ovog rada je da se ispita status esencijalnih elemenata (Cr, Mn, Co, Cu, Zn i Se) kod pacijenata obolelih od multiple skleroze, da se uporede njihove koncentracije sa vrednostima u kontrolnoj grupi i da se utvrdi postoji li značajna povezanost između promena u nivou ovih elemenata i patofizioloških procesa bolesti. Takođe, rad se bavi uporednom analizom studija koji su određivali koncentraciju esencijalnih elemenata u serumu i/ili pune krvi kod MS. Dobijeni rezultati mogu doprineti boljem razumevanju uloge mikroelemenata u etiopatogenezi MS i eventualno poslužiti kao osnova za razvoj novih dijagnostičkih i terapijskih pristupa zasnovanih na korekciji elementalnog statusa
Proizvodnja PR-10b proteina sočiva (Lens culinaris) rekombinantnom DNK tehnologijom
No full textCilj ovog rada bio je proizvodnja i eksperimentalna potvrda ekspresije rekombinantnog PR-10b proteina sočiva primenom rekombinantne DNK tehnologije u prokariotskom ekspresionom sistemu. Gen za PR-10b protein ukloniran je u ekspresioni vektor, a potom su sojevi Escherichia coli DH5α (radi umnožavanja plazmida) i BL21 (radi ekspresije proteina) transformisani plazmidom. Prisustvo gena od interesa u plazmidu potvrđeno je restrikcionom analizom, dok je ekspresija rekombinantnog proteina indukovana dodatkom IPTG-a. Uspešnost ekspresije analizirana je SDS-PAG elektroforezom a potvrđena je imunoblot metodom korišćenjem anti-His antitela. Na imunoblotu je detektovana traka na očekivanoj molekulskoj masi od približno 18 kDa, što odgovara rekombinantnom PR-10b proteinu. Dobijeni rezultati potvrđuju uspešnu proizvodnju rekombinantnog PR-10b proteina u bakterijskom ekspresionom sistemu. Proizvedeni rekombinantni PR-10b protein predstavlja osnovu za dalja ispitivanja njegove IgE-reaktivnosti i potencijalnu primenu u molekularnoj dijagnostici alergije na sočivo
Mentha piperita Essential Oil in Olive Oil: Extending Erythrocyte Viability and Limiting Bacterial Growth Under Serum-Free Conditions
No full textBackground: Serum-free culture of red blood cells (RBCs) typically leads to rapid loss of viability, limiting experimental and translational applications. Lipid-rich formulations and essential oils may provide biocompatible support for RBC integrity while limiting microbial overgrowth. Methods: RBCs from nine healthy adult donors were cultured in serum-free RPMI under four conditions: control, vehicle (olive oil, 1:100 v/v), genuine adenosine triphosphate (ATP)-oil® (1:100 v/v), and laboratory oil, “mimicking” ATP-oil®. Cultures were maintained for 18 days. Viability was assessed by light microscopy and trypan blue exclusion; bacterial contamination was qualitatively observed on day 18. Results: Genuine ATP-oil® maintained 35–45% RBC viability at day 18, whereas control and vehicle cultures declined rapidly. The mimicking preparation did not reproduce these effects. ATP-oil® immersion was associated with a qualitative reduction in bacterial contamination versus control, consistent with a dual action on RBC preservation and microbial suppression under serum-free conditions. Conclusions: Supplementation with ATP-oil® substantially prolongs RBC survival and limits bacterial overgrowth in vitro, outperforming commonly used serum or plasma supplements on a per-volume basis. These findings suggest potential applications for improving ex vivo handling or storage of blood components and for reducing background contamination in diagnostic microbiology. Further studies with larger cohorts are warranted to reveal underlying mechanisms and to define active constituents in order to standardize production
Određivanje metala u svežem kravljem mleku pomoću ICP-MS tehnike
No full textOvaj rad bavi se određivanjem metala u svežem kravljem mleku korišćenjem ICP-MS tehnike, koja se ističe visokom osetljivošću i selektivnošću u analizi elemenata. Analizom su obuhvaćeni metali, kao što su hrom, mangan, kobalt, nikl, bakar, cink, arsen, molibden, kadmijum, živa, olovo, bizmut, torijum i uranijum, koji mogu imati ozbiljne zdravstvene posledice. S obzirom na značaj kravljeg mleka u ishrani ljudi i potencijalne rizike kontaminacije metalima usled industrijalizacije i zagađenja životne sredine, neophodno je primeniti precizne analitičke metode za procenu kvaliteta ovog prehrambenog proizvoda.
U okviru istraživanja, posebna pažnja je posvećena pripremi uzoraka i optimizaciji uslova rada ICP-MS uređaja kako bi se postigla maksimalna tačnost i preciznost rezultata. Validacija metode je izvedena korišćenjem referentnih materijala i standardizovanih postupaka, čime je osigurana pouzdanost analize. Rezultati istraživanja su pokazali prisustvo različitih metala u svežem kravljem mleku, a njihove koncentracije su upoređene sa važećim standardima i preporukama za bezbednost hrane. Na osnovu dobijenih podataka, pružene su preporuke za smanjenje rizika od kontaminacije metala u mleku, čime se doprinosi poboljšanju kvaliteta i bezbednosti mlečnih proizvoda.
Ovaj rad pruža značajan doprinos razumevanju prisustva metala u mleku i predstavlja osnovu za dalja istraživanja u ovoj oblasti. Korišćenje ICP-MS tehnike omogućava detaljnu i pouzdanu analizu, što je ključno za zaštitu javnog zdravlja i unapređenje standarda kvaliteta hrane
Elementarni status zdravih tkiva pluća
No full textCilj ovog rada je ispitivanje elementarnog statusa zdravog plućnog tkiva, kao i utvrđivanje koncentracije analiziranih elemenata u ispitivanim uzorcima. Pored toga, cilj rada je i poređenje dobijenih rezultata sa podacima iz naučne literature različitih zemalja kako bi se procenilo da li se utvrđene vrednosti nalaze u okviru vrednosti koje su zabeležene u drugim istraživanjima
Biological responses to 30 mT static magnetic field in young and 36-month-old rats
No full textThis study aimed to investigate the effects of subchronic exposure to a 30 mT static magnetic field
(SMF) on hematological parameters, spleen and tibia cellularity in 36-month-old and young rats.
A total of 27 rats were divided into four groups (Young, Young SMF, Old, Old SMF) and two groups
were exposed to SMF for 10 weeks. After exposure period, blood counts, neutrophil-to-lymphocyte
ratio (NLR, an index of systemic inflammation), platelet-to-lymphocyte ratio (PLR, a platelet-based
inflammatory marker) and cellularity of immune-related organs were analyzed. SMF exposure
reduced lymphocyte counts and increased NLR in both age groups, while PLR increased only in
young rats. In 36-month-old rats, SMF significantly reduced platelet counts, whereas this effect was
not observed in young animals. SMF exposure also enhanced tibial and splenic cellularity in both
groups but exerted opposite effects on the proportions of lymphocytes and erythrocytes depending on age. These findings suggest age-dependent immune modulation by SMF. In young animals,
SMF likely promoted a proinflammatory shift, reflected by elevated NLR and PLR. In contrast, in 36-
month-old rats, SMF may act as a nonspecific physiological stressor, potentially triggering the
General Adaptation Syndrome (three-stage stress response), leading to corticosterone-mediated
immunosuppression and cell redistribution. To our knowledge, this is the first study demonstrating
age-dependent differential modulation of NLR and PLR by subchronic SMF exposure, linking
proinflammatory shifts in youth with stress-related immunosuppression in aging. Overall, age
appears to be a critical factor in determining the biological responses to SMF, underscoring the
need for age-specific evaluation of SMF exposure
Elementarni status malignih tkiva pluća
No full textCilj ovog rada je ispitivanje elementarnog statusa malignog plućnog tkiva i poređenje dobijenih rezultata sa koncentracijama elemenata u zdravom plućnom tkivu. Dodatni cilj istraživanja je poređenje dobijenih rezultata sa podacima iz naučne literature kako bi se utvrdile eventualne sličnosti i razlike u koncentracijama analiziranih elemenata
Differential Allergenicity and Heavy Metal Content in Dactylis glomerata and Lolium perenne Pollen Across Contrasting Environments
No full textAir pollution and heavy metals can alter the composition and allergenicity of grass pollen, yet field-based evidence remains scarce. This study investigates Dactylis glomerata and Lolium perenne pollen, and how urban/industrial conditions influence sub-pollen particle (SPP) release, chemical composition, and IgE reactivity—extending prior work on Phleum pratense pollen. Pollen was collected near Kruševac (central Serbia) from two sites ~10 km apart: a rural area (D1/L1) and a location adjacent toa regiona l road and chemical plant (D2/L2). SPP release during osmolysis was quantified by light microscopy; protein profiles were assessed via 1D SDS-PAGE; elemental content analyzed by ICP- OES/MS; PAHs by GC–MS; and IgE binding measured by ELISA, using sera from a previous study (16 grass pollen–allergic patients). Urban samples released significantly more SPP
(several-fold increase) and showed elevated protein expression with altered protein/allergen patterns. D2 pollen contained ~10× more As and ~5× more Cd than D1; L. perenne from L2 had elevated Ni (~15 μg/g) and 5× more indium than L1. Acenaphthylene was detected only in polluted samples, while anthracene was present only in D2 pollen. Notably, 56% of sera showed stronger IgE
binding to contaminated D. glomerata, suggesting heightened allergic potential at equal pollen loads. These findings support a link between air pollution and increased respiratory allergy risk, highlighting pollen's potential as a bioindicator of environmental contamination
Insights into adaptation mechanisms and survival strategies of Pseudomonas chlororaphis subsp. aurantiaca: A comparative proteomic study under PFOA exposure
No full textPerfluorooctanoic acid (PFOA), increasingly detected at extreme concentrations in industrial hotspots, caused a reduction in growth and a prolonged lag phase in Pseudomonas chlororaphis subsp. aurantiaca. In order to reveal microbial adaptation mechanisms and survival strategies under exposure to PFOA, a comparative proteomic analysis was undertaken. The up-regulation of phosphoglycerol transferase, lipoproteins, and long-chain fatty acid synthesis, together with the down regulation of cis unsaturation of fatty acids and changes in specific membrane-embedded porins, indicate alterations in membrane structure, fluidity, and permeability. The up-regulation of the divalent cation–regulated outer membrane protein H1, accompanied by the down-regulation of zinc and other metal transporters, reflect changes in metal ion homeostasis. In particular, altered iron homeostasis and expression of iron-, Fe-S clusters-, and heme-containing proteins were detected, along with the reduced activity of some iron-containing enzymes, as a result of inhibition by PFOA. Up-regulated enzymes of the methylcitrate and the glyoxylate cycles indicate alterations in central metabolic pathways associated with lipid metabolism in PFOA-treated cells. Changes in the respiratory chain may influence enhanced superoxide radical formation, triggering increased ROS production and the up-regulation of antioxidant enzymes, except those involved in thiol-based redox processes. In addition, PFOA alters the regulation of virulence-associated proteins
Analiza CF3-CF3 interakcija u Kembričkoj banci podataka
No full textUgljenik je osnovni element organske hemije i života, zahvaljujući sposobnosti da gradi stabilne kovalentne veze, lance i prstenove, što omogućava nastanak velikog broja različitih organskih jedinjenja. Fluor je, sa druge strane, izuzetno elektronegativan i reaktivan element koji značajno utiče na osobine molekula u koje je ugrađen. Veza između ugljenika i fluora (C–F) jedna je od najjačih polarnih kovalentnih veza, što fluorovanim jedinjenjima daje veliku hemijsku i termičku stabilnost. Zbog toga fluor ima važnu ulogu u razvoju materijala i farmaceutskih supstanci, jer njegovo prisustvo može značajno uticati na fizičko-hemijske i biološke osobine molekula.
Izvršena je pretraga Kristalografske strukturne banke podataka (CSD, verzija 5.46, November 2024) nearomatičnih jedinjenja sa ciljem ispitivanja C–F / F–C interakcija. U analizu su uključene samo strukture dobijene iz monokristala sa kompletnim trodimenzionalnim koordinatama, bez polimera, grešaka i disordera, uz uslov da je kristalografski R-faktor ≤ 0.05. Jedan od glavnih kriterijuma bilo je rastojanje između dva atoma fluora ograničeno do 3.5 Å. Analizirani su različiti geometrijski parametri, uključujući rastojanja između atoma i vektorske uglove C–F veza, kao i torzioni ugao C1–F1–F2–C2. Na osnovu zadatih kriterijuma identifikovano je ukupno 41.418 kontakata koji su korišćeni za dalju analizu interakcija.
Nakon analiziranja rezultata došlo se do zaključka da je najzastupljenije F-F rastojanje oko 3.1–3.3 Å i da postoje bliski F-F kontakti. Rezultati histograma pokazuju da je antiparalelna orijentacija CF₃ grupa, u kojoj su grupe usmerene jedna prema drugoj najčešća. Takođe, torzioni uglovi T ukazuju da je anti konformacija najzastupljenija, sa maksimumima uglavnom oko 180°