imagine (Institute of molecular genetics and genetic engineering)
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Use of Wilms Tumor 1 Gene Expression as a Reliable Marker for Prognosis and Minimal Residual Disease Monitoring in Acute Myeloid Leukemia With Normal Karyotype Patients
The aim of the present study was to test the possibility for the usage of the WT1 (Wilms tumor 1) expression level as an additional biomarker for prognosis and minimal residual disease (MRD) monitoring in patients with acute myeloid leukemia with normal karyotype (AML-NK). We found that overexpression of WT1 had a negative effect on treatment outcome. It was a suitable marker for MRD monitoring and a marker for refined risk stratification of AML-NK patients. Background: Acute myeloid leukemia with normal karyotype (AML-NK) represents the largest group of AML patients classified with an intermediate prognosis. A constant need exists to introduce new molecular markers for more precise risk stratification and for minimal residual disease (MRD) monitoring. Patients and Methods: Quantitative assessment of Wilms tumor 1 (WT1) gene transcripts was performed using real-time polymerase chain reaction. The bone marrow samples were collected at the diagnosis from 104 AML-NK patients and from 34 of these patients during follow-up or disease relapse. Results: We found that overexpression of the WT1 gene (WT1(high) status), present in 25.5% of patients, was an independent unfavorable factor for achieving complete remission. WT1(high) status was also associated with resistance to therapy and shorter disease-free survival and overall survival. Assessment of the log reduction value of WT1 expression, measured in paired diagnosis/complete remission samples, revealed that patients with a log reduction of lt 2 had a tendency toward shorter disease-free survival and overall survival and a greater incidence of disease relapse. Combining WT1 gene expression status with NPM1 and FLT3-ITD mutational status, we found that the tumor behavior of intermediate patients (FLT3(-)ITD-/NPM1(-) double negative) with WT1(high) status is almost the same as the tumor behavior of the adverse risk group. Conclusion: WT1 expression status represents a good molecular marker of prognosis, response to treatment, and MRD monitoring. Above all, the usage of the WT1 expression level as an additional marker for more precise risk stratification of AML-NK patients could lead to more adapted, personalized treatment protocols
Uncovering Differences in Virulence Markers Associated with Achromobacter Species of CF and Non-CF Origin
Achromobacter spp. are recognized as emerging pathogens in hospitalized as well as in cystic fibrosis (CF) patients. From 2012 to 2015, we collected 69 clinical isolates (41 patient) of Achromobacter spp. from 13 patients with CF (CF isolates, n = 32) and 28 patients receiving care for other health conditions (non-CF isolates, n = 37). Molecular epidemiology and virulence potential of isolates were examined. Antimicrobial susceptibility, motility, ability to form biofilms and binding affinity to mucin, collagen, and fibronectin were tested to assess their virulence traits. The nrdA gene sequencing showed that A. xylosoxidans was the most prevalent species in both CF and non-CF patients. CF patients were also colonized with A. dolens/A, ruhlandii, A. insuavis, and A. spiritinus strains while non-CF group was somewhat less heterogenous, although A. insuavis, A. insolitus, and A. piechaudii strains were detected beside A. xylosoxidans. Three strains displayed clonal distribution, one among patients from the CF group and two among non-CF patients. No significant differences in susceptibility to antimicrobials were observed between CF and non-CF patients. About one third of the isolates were classified as strong biofilm producers, and the proportion of CF and non-CF isolates with the ability to form biofilm was almost identical. CF isolates were less motile compared to the non-CF group and no correlation was found between swimming phenotype and biofilm formation. On the other hand, CF isolates exhibited higher affinity to bind mucin, collagen, and fibronectin. In generall, CF isolates from our study exhibited in vitro properties that could be of importance for the colonization of CF patients
SOX14 activates the p53 signaling pathway and induces apoptosis in a cervical carcinoma cell line
SOX14 is a member of the SOX family of transcription factors mainly involved in the regulation of neural development. Recently, it became evident that SOX14 is one of four hyper-methylated genes in cervical carcinoma, considered as a tumor suppressor candidate in this type of malignancy. In this paper we elucidated the role of SOX14 in the regulation of malignant properties of cervical carcinoma cells in vitro. Functional analysis performed in HeLa cells revealed that SOX14 overexpression decreased viability and promoted apoptosis through altering the expression of apoptosis related genes. Our results demonstrated that overexpression of SOX14 initiated accumulation of p53, demonstrating potential cross-talk between SOX14 and the p53 signaling pathway. Further analysis unambiguously showed that SOX14 triggered posttranslational modification of p53 protein, as detected by the significantly increased level of phospho-p53 (Ser-15) in SOX14-overexpressing HeLa cells. Moreover, the obtained results revealed that SOX14 activated p53 protein, which was confirmed by elevated p21 Waf1/Cip1, a well known target gene of p53. This study advances our understanding about the role of SOX14 and might explain the molecular mechanism by which this transcription factor could exert tumor suppressor properties in cervical carcinoma
Temperature, pH and Trimethoprim-Sulfamethoxazole Are Potent Inhibitors of Biofilm Formation by Stenotrophomonas maltophilia Clinical Isolates
Stenotrophomonas maltophilia, an opportunistic pathogen usually connected with healthcare-associated infections, is an environmental bacterium. Intrinsic resistance to multiple antibiotics, with different virulence determinants in the last decade classified this bacterium in the group of global multiple drug resistant (MDR) organism. S. maltophilia clinical isolates, were collected from tertiary care pediatric hospital in Belgrade, Serbia to investigate influence of different factors on biofilm formation, kinetics of biofilm formation for strong biofilm producers and effect of trimethoprim-sulfamethoxazole (TMP/SMX) on formed biofilm. Most of the isolates (89.8%) were able to form a biofilm. Analysis of biofilm formation in different growth conditions showed that changing of temeperature and pH had the stronggest effect on biofilm formation almost equally in group of cystic fibrosis (CF) and non-CF strains. TMP/SMX in concentration of 50 mu g/ml reduced completely 24 h old biofilms while concentration of 25 mu g/ml effects formed biofilms in a strain dependent manner. Among strains able to form strong biofilm CF isolates formed biofilm slower than non-CF isolates, while shaking conditions did not affect biofilm formation. Swimming motility was detected in both CF and non-CF isolates, however more motile strain formed stronger biofilms. This study suggests that temperature, pH and TMP/SMX had the strongest influence on biofilm formation in analyzed collection of S. maltophilia. A positive correlation between motility and strength of formed biofilm was demonstrated
Ontogenetic stage, plant vigor and sex mediate herbivory loads in a dioecious understory herb
Plant-herbivore interactions can be mediated by plant apparency, defensive and nutritional quality traits that change through plant ontogeny, resulting in age-specific herbivory. In dioecious species, opposing allocation patterns in defense may lead to sex-biased herbivory. Here, we examine how onto stage and plant sex determine levels of herbivore damage in understory herb Mercurialis perennis under field conditions. We analyzed variation in plant size (height, total leaf area), physical (specific leaf area) and chemical (total phenolic and condensed tannins contents) defense, and nutritional quality (total water, soluble protein and nonstructural carbohydrate contents) during the shift from reproductive to post-reproductive stage. Furthermore, we explored correlations between the analyzed traits and levels of foliar damage. Post-reproductive plants had lower levels of chemical defense, and larger leaf area removed, in spite of having lower nutritive quality. Opposing patterns of intersexual differences were detected in protein and phenolic contents during reproductive stage, while in post-reproductive stage total leaf area was sexually dimorphic. Female-biased herbivory was apparent only after reproduction. Plant size parameters combined with condensed tannins content determined levels of foliar damage during post reproductive stage, while the only trait covarying with herbivory in reproductive stage was total nonstructural carbohydrate content. Our results support claims of optimal defense theory - sensitive stage of reproduction was better defended. We conclude that different combinations of plant traits mediated interactions with herbivores in mature stages. Differences in reproductive allocation between the sexes may not immediately translate into different levels of damage, stressing the need for considering different ontogenetic stages when exploring sex bias in herbivory
Transport of silver nanoparticles from nanocomposite Ag/alginate hydrogels under conditions mimicking tissue implantation
The aim of this work was to assess phenomena occurring during AgNP transport from nanocomposite Ag/alginate hydrogels under conditions relevant for potential biomedical applications as antimicrobial soft tissue implants. First, we have studied AgNP migration from the nanocomposite to the adjacent alginate hydrogel mimicking soft tissue next to the implant. AgNP deposition was carried out by the initial burst release lasting for similar to 24 h yielding large aggregates on hydrogel surfaces and smaller clusters (similar to 400 nm in size) inside. However, the overall released content was low (0.67%) indicating high nanocomposite stability. In the next experimental series, release of AgNPs, 10-30 nm in size, from Ag/alginate microbeads in water was investigated under static conditions as well as under continuous perfusion mimicking vascularized tissues. Mathematical modeling has revealed AgNP release by diffusion under static conditions with the diffusion coefficient within the Ag/alginate hydrogel of 6.9x10(-19) m(2) s(-1). Conversely, continuous perfusion induced increased AgNP release by convection with the interstitial fluid velocity estimated as 4.6 nm s(-1). Overall, the obtained results indicated the influence of hydrodynamic conditions at the implantation site on silver release and potential implant functionality, which should be investigated at the experimentation beginning using appropriate in vitro systems
Epigenetic signature of early trauma: differences in the FKBP5 DNA methylation levels among psychotic patients, their healthy siblings and controls
Synthesis of core-shell hematite (α-Fe 2 O 3 ) nanoplates: Quantitative analysis of the particle structure and shape, high coercivity and low cytotoxicity
Hematite core-shell nanoparticles with plate-like morphology were synthesized using a one-step hydrothermal synthesis. An XRPD analysis indicates that the sample consist of single-phase alpha-Fe2O3 nanoparticles. SEM and TEM measurements show that the hematite sample is composed of uniform core-shell nanoplates with 10-20 nm thickness, 80-100 nm landscape dimensions (aspect ratio 5) and 3-4 nm thickness of the surface shells. We used computational methods for the quantitative analysis of the core-shell particle structure and circularity shape descriptor for the quantitative shape analysis of the nanoparticles from TEM micrographs. The calculated results indicated that a percentage of the shell area in the nanoparticle area (share [%]) is significant. The determined values of circularity in the perpendicular and oblique perspective clearly show shape anisotropy of the nanoplates. The magnetic properties revealed the ferromagnetic-like properties at room temperature with high coercivity H-C = 2340 Oe, pointing to the shape and surface effects. These results signify core-shell hematite nanoparticles' for practical applications in magnetic devices. The synthesized hematite plate-like nanoparticles exhibit low cytotoxicity levels on the human lung fibroblasts (MRC5) cell line demonstrating the safe use of these nanoparticles for biomedical applications.Related to accepted verison: [https://imagine.imgge.bg.ac.rs/handle/123456789/1806
Mononuclear gold(III) complexes with L-histidine-containing dipeptides: tuning the structural and biological properties by variation of the N-terminal amino acid and counter anion
Gold(III) complexes with different L-histidine-containing dipeptides, [Au(Gly-L-His-N-A,N-P,N3)Cl]Cl center dot 3H(2)O (1a), [Au(Gly-L-His-N-A,N-P,N-3)Cl]NO3 center dot 1.25H(2)O (1b), [Au(L-Ala-L-His-N-A,N-P,N-3)Cl][AuCl4]center dot H2O (2a), [Au(L-Ala-L-His-N-A,N-P,N-3)Cl]NO3 center dot 2.5H(2)O (2b), [Au(L-Val-L-His-N-A,N-P,N-3)Cl]Cl center dot 2H(2)O (3), [Au(L-Leu-L-His-N-A,N-P,N-3)Cl]Cl (4a) and [Au(L-Leu-L-His-N-A,N-P,N-3)Cl][AuCl4]center dot H2O (4b), have been synthesized and structurally characterized by spectroscopic (1H NMR, IR and UV-vis) and single-crystal X-ray diffraction techniques. The antimicrobial efficiency of these gold(III) complexes, along with K[AuCl4] and the corresponding dipeptides, was evaluated against the broad panel of Gram-positive and Gram-negative bacteria and fungi, displaying their moderate inhibiting activity. Moreover, the cytotoxic properties of the investigated complexes were assessed against the normal human lung fibroblast cell line (MRC5) and two human cancer, cervix (HeLa) and lung (A549) cell lines. None of the complexes exerted significant cytotoxic activity; nevertheless complexes that did show selectivity in terms of cancer vs. normal cell lines (2a/b and 4a/b) have been evaluated using zebrafish (Danio rerio) embryos for toxicity and antiangiogenic potential. Although the gold(III) complexes achieved an antiangiogenic effect comparable to the known angiogenic inhibitors auranofin and sunitinib malate at 30-fold higher concentrations, they had no cardiovascular side effects, which commonly accompany auranofin and sunitinib malate treatment. Finally, binding of the gold(III) complexes to the active sites of both human and bacterial (Escherichia coli) thioredoxin reductases (TrxRs) was demonstrated by conducting a molecular docking study, suggesting that the mechanism of biological action of these complexes can be associated with their interaction with the TrxR active site.Related to accepted verison: [https://imagine.imgge.bg.ac.rs/handle/123456789/1807]Supplementary material: [https://imagine.imgge.bg.ac.rs/handle/123456789/1808
Ixodes ricinus immunogenic saliva protein, homologue to Amblyomma americanum AV422: Determining its potential for use in tick bite confirmation
Tick bites often go unnoticed, so specific reliable tests are needed to confirm them for prompt diagnosis and treatment of tick-borne diseases. One of the promising candidates for developing such a test is AV422, a tick saliva protein that has been conserved across tick genera. In this study, we demonstrate the potential of the AV422 homologue from Ixodes ricinus to be used for tick bite detection for both Prostriata and Metastriata. We expressed recombinant (r) I. ricinus (Ir) AV422 in E. coli and subjected it to Western blot analysis using rat antibodies to saliva proteins of both I. ricinus (Prostriata) and Dermacentor reticulatus (Metastriata) larvae. Our data demonstrate that rIrAV422 specifically bound to antibodies from sera of rats used for both I. ricinus and D. reticulatus larvae feeding, but not to antibodies from control serum, emphasizing its specificity since tick bites were the sole cause of sera reactivity