Sinteza, NMR i DFT proračunavanja i ispitivanje antimikrobne aktivnosti Zn(II) kompleksa sa N-benziloksikarbonil-S-alaninom

In this study, the first complexes of Zn(II) with the N-benzyloxycarbonyl-S-alaninato ligand (N-Boc-S-ala) were synthesized. The new complexes were characterized by elemental analysis, conductometric measurements, IR. (1)H-NMR, (13)C-NMR and 2D-NMR spectroscopy. On the basis of the experimental data, tetrahedral geometry of the Zn(II) complexes was proposed. A very good agreement between the NMR and DFT calculated data was obtained. Investigation of antimicrobial activity of the newly synthesized complexes was also performed. It was established that [Zn(N-Boc-S-ala)(2)] was selective and acts only on Candida aibicans.U ovom radu su sintetizovani prvi kompleksi Zn(II) sa N-benziloksikarbonil-S-alaninato ligandom (N-Boc-S-ala). Kompleksi su okarakterisani elementalnom analizom, konduktometrijskim merenjem, IR, 1H-NMR, 13C-NMR i 2D-NMR spektroskopijom. Tetraedarska geometrija Zn(II) kompleksa pretpostavljena je na osnovu eksperimentalnih podataka. Dobijeno je veoma dobro slaganje između NMR i DFT podataka. Ispitivana je antimikrobna aktivnost novosintetizovanih kompleksa. Ustanovljeno je da je [Zn(N-Boc-S-ala)2] kompleks selektivan i da deluje samo na gljivu Candida albicans

Heteropentanuclear Oxalato-Bridged nd-4f (n=4, 5) Metal Complexes with NO Ligand: Synthesis, Crystal Structures, Aqueous Stability and Antiproliferative Activity

A series of heteropentanuclear oxalate-bridged Ru(NO)-Ln (4d-4f) metal complexes of the general formula (nBu(4)N)(5)[Ln{RuCl3(-ox)(NO)}(4)], where Ln=Y (2), Gd (3), Tb (4), Dy (5) and ox=oxalate anion, were obtained by treatment of (nBu(4)N)(2)[RuCl3(ox)(NO)] (1) with the respective lanthanide salt in 4:1 molar ratio. The compounds were characterized by elemental analysis, IR spectroscopy, electrospray ionization (ESI) mass spectrometry, while 1, 2, and 5 were in addition analyzed by X-ray crystallography, 1 by Ru K-edge XAS and 1 and 2 by (CNMR)-C-13 spectroscopy. X-ray diffraction showed that in 2 and 5 four complex anions [RuCl3(ox)(NO)](2-) are coordinated to Y-III and Dy-III, respectively, with formation of [Ln{RuCl3(-ox)(NO)}(4)](5-) (Ln=Y, Dy). While Y-III is eight-coordinate in 2, Dy-III is nine-coordinate in 5, with an additional coordination of an EtOH molecule. The negative charge is counterbalanced by five nBu(4)N(+) ions present in the crystal structure. The stability of complexes 2 and 5 in aqueous medium was monitored by UV/Vis spectroscopy. The antiproliferative activity of ruthenium-lanthanide complexes 2-5 were assayed in two human cancer cell lines (HeLa and A549) and in a noncancerous cell line (MRC-5) and compared with those obtained for the previously reported Os(NO)-Ln (5d-4f) analogues (nBu(4)N)(5)[Ln{OsCl3(ox)(NO)}(4)] (Ln=Y (6), Gd (7), Tb (8), Dy (9)). Complexes 2-5 were found to be slightly more active than 1 in inhibiting the proliferation of HeLa and A549 cells, and significantly more cytotoxic than 5d-4f metal complexes 6-9 in terms of IC50 values. The highest antiproliferative activity with IC50 values of 20.0 and 22.4M was found for 4 in HeLa and A549 cell lines, respectively. These cytotoxicity results are in accord with the presented ICP-MS data, indicating five- to eightfold greater accumulation of ruthenium versus osmium in human A549 cancer cells

The role of CD69 molecule in the mucosal immune responses of the intestine

CD69 is highly expressed by lymphocytes at mucosal surfaces, but its role in immune responses is largely unknown. I aimed to investigate the role of CD69 in mucosal immune responses. The expression of CD69 by spleen, mesenteric lymph nodes, small intestinal and colonic lamina propria CD4 T cells was determined in specific pathogen free B6 and T cell receptor (TCR) transgenic mice and in germ-free B6 mice and intestinal microflora depleted TCR transgenic animals. Colitis was induced by transplanting RAG-/- mice with B6, CD69-/- or type I interferon receptor (IFNAR)-deficient CD45RBhigh CD4 T cells or by dextran sodium sulphate (DSS) treatment. CD69 expression by CD4 T cells is induced by the intestinal microflora, oral delivery of specific antigen or type I interfrons. CD69-/- CD4 T cells produce increased amounts of pro-inflammatory cytokines IFN-gamma, TNF-alpha and IL-21 and decreased amounts of regulatory cytokine TGF-ß1. Furthermore, CD69-deficient CD4 T cells show reduced potential to differentiate into Foxp3+ regulatory cells (Treg) in vivo and in vitro. The transfer of CD69-/- CD4 T cells into RAG-/- hosts or DSS administration to CD69-/- mice induce an accelerated colitis. CD69-/- CD4 T cells express higher levels of chemokine ligands and receptors and migrate more efficiently to the intestinal tissues in vivo compared to B6 cells. Oral tolerance is impaired in CD69-/- and IFNAR-/- mice comparing to B6 and OT-II x RAG-/- animals. Polyinosine polycytidylic acid (poly (I:C)) treatment of RAG-/- mice transplanted with B6 but not CD69-/- or IFNAR-/- CD4 T cells attenuate transfer colitis. In the line with this, CD69 deficiency on CD4 T cells affected poly (I:C)-induced IFN-ß1 expression. CD69 deficiency led to the increased production of pro-inflammatory cytokines and chemokines, reduced Foxp3+ Treg cell induction, impaired oral tolerance and more severe colitis. Hence, the activation antigen CD69 plays an important role in regulating mucosal immune responses

Omsorg och undervisning i förskolan : En kvalitativ studie om begreppens relationer

Syftet med denna studie var att undersöka hur undervisning och omsorg kan samverka i förskolans verksamhet, med fokus på de mellanmänskliga mötena mellan förskollärare och barn. Samt hur i dessa möten undervisningen tar sin utgångspunkt i omsorgen. Studien utgår från en kvalitativ metod med semistrukturerade intervjuer av åtta förskollärare som har ansvar för planering och arbete med undervisning i förskolan. Studiens teori har sin utgångspunkt i det sociokulturella perspektivet med fokus på de centrala begreppen den proximala utvecklingszonen, artefakter, mediering och scaffolding. I resultatet framkom det att förskollärarna anser att omsorgen utgör en förutsättning för undervisningen. Förskollärarna betonar även vikten av relationer som utgångspunkt i undervisningen. Slutsatsen av studien belyser att omsorg och undervisning samverkar på olika sätt. Däremot påvisar resultaten en ambivalens vad gäller undervisningen i förskolan och dess mätbara funktion gentemot omsorgens

Omsorg och undervisning i förskolan : En kvalitativ studie om begreppens relationer

Syftet med denna studie var att undersöka hur undervisning och omsorg kan samverka i förskolans verksamhet, med fokus på de mellanmänskliga mötena mellan förskollärare och barn. Samt hur i dessa möten undervisningen tar sin utgångspunkt i omsorgen. Studien utgår från en kvalitativ metod med semistrukturerade intervjuer av åtta förskollärare som har ansvar för planering och arbete med undervisning i förskolan. Studiens teori har sin utgångspunkt i det sociokulturella perspektivet med fokus på de centrala begreppen den proximala utvecklingszonen, artefakter, mediering och scaffolding. I resultatet framkom det att förskollärarna anser att omsorgen utgör en förutsättning för undervisningen. Förskollärarna betonar även vikten av relationer som utgångspunkt i undervisningen. Slutsatsen av studien belyser att omsorg och undervisning samverkar på olika sätt. Däremot påvisar resultaten en ambivalens vad gäller undervisningen i förskolan och dess mätbara funktion gentemot omsorgens

Gastro-intestinal tract: The leading role of mucosal immunity

An understanding of mucosal immunity is essential for the comprehension of intestinal diseases that are often caused by a complex interplay between host factors, environmental influences and the intestinal microbiota. Not only improvements in endoscopic techniques, but also advances in high throughput sequencing technologies, have expanded knowledge of how intestinal diseases develop. This review discusses how the host interacts with intestinal microbiota by the direct contact of host receptors with highly conserved structural motifs or molecules of microbes and also by microbe-derived metabolites (produced by the microbe during adaptation to the gut environment), such as short-chain fatty acids, vitamins, bile acids and amino acids. These metabolites are recognised by metabolite-sensing receptors expressed by immune cells to influence functions of macrophages, dendritic cells and T cells, such as migration, conversion and maintenance of regulatory T cells and regulation of proinflammatory cytokine production, which is essential for the maintenance of intestinal homeostasis and the development of intestinal diseases, such as inflammatory bowel diseases. First interventions in these complex interactions between microbe-derived metabolites and the host immune system for the treatment of gastrointestinal diseases, such as modification of the diet, treatment with antibiotics, application of probiotics and faecal microbiota transplantation, have been introduced into the clinic. Specific targeting of metabolite sensing receptors for the treatment of gastrointestinal diseases is in development. In future, precision medicine approaches that consider individual variability in genes, the microbiota, the environment and lifestyle will become increasingly important for the care of patients with gastrointestinal diseases

Fluctuations of the number of adsorbed micro/nanoparticles in sensors for measurement of particle concentration in air and liquid environments

A theoretical model of fluctuations of the number of adsorbed micro/nanoparticles in environmental sensors operating in air and liquids is presented, taking into account the effects of the mass transfer processes of the target particles in a sensor reaction chamber. The expressions for the total power of the corresponding adsorption-desorption noise, and for the corresponding signal-to-noise ratio are also derived. The presented analysis shows that the transfer processes can have a significant influence on the sensors limiting performance. The influence on both the fluctuations spectrum and the signal-to-noise ratio is estimated at different values of target particles concentration, functionalization sites surface density, and adsorption and desorption rate constants (the values are chosen from the ranges corresponding to real conditions). The analysis provides the guidelines for optimization of sensor design and operating conditions for the given target substance and sensor functionalization, in order to decrease the influence of the mass transfer, thus improving the ultimate performance (e.g., minimal detectable signal, signal-to-noise ratio) of sensors for particle detection. The calculations we performed show that it is possible to increase the signal-to-noise ratio for as much as two orders of magnitude by using optimization that eliminates the mass transfer influence.Prikazan je teorijski model fluktuacija broja adsorbovanih mikro/nanočestica kod senzora za merenje parametara životne sredine, koji rade u vazduhu ili u tečnoj sredini. Model uzima u obzir uticaj procesa prenosa mase ciljnih čestica u reakcionoj komori senzora. Izvedeni su izrazi za snagu odgovarajućeg adsorpciono-desorpcionog šuma, kao i za odgovarajući odnos signal/šum. Prikazana analiza pokazuje da procesi prenosa mase mogu značajno da utiču na granične performanse senzora. Procenjen je uticaj prenosa mase na spektar fluktuacija i na odnos signal/šum pri različitim vrednostima koncentracije ciljnih čestica, površinske gustine funkcionalizujućih mesta i konstanti adsorpcije i desorpcije (izabrane vrednosti parametara su iz opsega koji odgovaraju realnim uslovima). Analiza omogućuje da se donesu zaključci potrebni za optimizaciju dizajna senzora i radnih uslova u smislu smanjenja uticaja prenosa mase, i da se time postigne poboljšanje graničnih performansi (npr. smanjenje minimalnog detektabilnog signala) senzora za detekciju čestica

Development of an Antigen-driven Colitis Model to Study Presentation of Antigens by Antigen Presenting Cells to T Cells

Inflammatory bowel disease (IBD) is a chronic inflammation which affects the gastrointestinal tract (GIT). One of the best ways to study the immunological mechanisms involved during the disease is the T cell transfer model of colitis. In this model, immunodeficient mice (RAG(-/-) recipients) are reconstituted with naive CD4(+) T cells from healthy wild type hosts. This model allows examination of the earliest immunological events leading to disease and chronic inflammation, when the gut inflammation perpetuates but does not depend on a defined antigen. To study the potential role of antigen presenting cells (APCs) in the disease process, it is helpful to have an antigen-driven disease model, in which a defined commensal-derived antigen leads to colitis. An antigen driven-colitis model has hence been developed. In this model OT-II CD4(+) T cells, that can recognize only specific epitopes in the OVA protein, are transferred into RAG(-/-) hosts challenged with CFP-OVA-expressing E. coli. This model allows the examination of interactions between APCs and T cells in the lamina propria

UV-killed <i>B</i>. <i>bifidum</i> S17 does not protect C57BL/6J mice against DSS-induced colitis.

<p>(A) Effect of UV-killed <i>B</i>. <i>bifidum</i> S17/pMGC on DSS-induced weight loss (A) and increase in colonic weight:length ratio (B). Mice were treated with <i>B</i>. <i>bifidum</i> S17/pMGC and challenged with DSS (DSS/S17). Control mice received PBS as placebo and water with or without DSS (DSS/PBS and H₂O/PBS respectively, all groups <i>n</i> = 5). Values are mean ± standard error of the mean. Statistical analysis was performed by one-way ANOVA with Bonferroni post-test analysis for each day (B) or at the end of the trial (C). Asterisks indicate levels of statistical significance differences for comparison to H₂O/PBS group (*: p < 0.05; ***: p<0.001).</p

<i>B</i>. <i>bifidum</i> S17 is able to stably colonize GF but not SPF C57BL/6J mice.

<p>Fecal shedding of <i>B</i>. <i>bifidum</i> S17/pMGC following oral administration of three doses of 2×10⁹ CFU per animal on consecutive days (indicated as a black arrow) to C57BL/6J mice under SPF (A) or GF (B) conditions. Values are CFU/g feces and are mean ± standard error of the mean (<i>n</i> = 6 animals per experiment).</p