Publications by authors named "Constantinos E Vorgias"

Microarray experiments, a mainstay in gene expression analysis for nearly two decades, pose challenges due to their complexity. To address this, we introduce DExplore, a user-friendly web application enabling researchers to detect differentially expressed genes using data from NCBI's GEO. Developed with R, Shiny, and Bioconductor, DExplore integrates WebGestalt for functional enrichment analysis.

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Sfela is a white brined Greek cheese of protected designation of origin (PDO) produced in the Peloponnese region from ovine, caprine milk, or a mixture of the two. Despite the PDO status of Sfela, very few studies have addressed its properties, including its microbiology. For this reason, we decided to investigate the microbiome of two PDO industrial Sfela cheese samples along with two non-PDO variants, namely Sfela touloumotiri and Xerosfeli.

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Immune checkpoint inhibitors (ICIs) exhibit remarkable antitumor activity and immune-related cardiotoxicity of unknown pathomechanism. The aim of the study was to investigate the ICI class-dependent cardiotoxicity in vitro and pembrolizumab's (Pem's) cardiotoxicity in vivo, seeking for translational prevention means. Cytotoxicity was investigated in primary cardiomyocytes and splenocytes, incubated with ipilimumab, Pem and avelumab.

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Galactosemia is an inherited disorder caused by mutations in the three genes that encode enzymes implicated in galactose catabolism. Currently, the only available treatment for galactosemia is life-long dietary restriction of galactose/lactose, and despite treatment, it might result in long-term complications. Here, we present five cases of newborn patients with elevated galactose levels, identified in the context of the newborn screening program.

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Anaerobic methane metabolism is among the hallmarks of Archaea, originating very early in their evolution. Here, we show that the ancestor of methane metabolizers was an autotrophic CO-reducing hydrogenotrophic methanogen that possessed the two main complexes, methyl-CoM reductase (Mcr) and tetrahydromethanopterin-CoM methyltransferase (Mtr), the anaplerotic hydrogenases Eha and Ehb, and a set of other genes collectively called "methanogenesis markers" but could not oxidize alkanes. Overturning recent inferences, we demonstrate that methyl-dependent hydrogenotrophic methanogenesis has emerged multiple times independently, either due to a loss of Mtr while Mcr is inherited vertically or from an ancient lateral acquisition of Mcr.

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Background/aim: Numerous missense mutations have been determined in the BRCT domain of the BRCA1 gene, affecting localization and interaction of BRCA1 with other proteins.

Materials And Methods: We examined whether the M1775K and V1809F mutations in the BRCT domain affect BRCA1 cellular localization. Cells were transfected with pEGFP-C3-BRCA1 and detected by fluorescence microscopy.

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Cystathionine -synthase (CBS) is a key enzyme in the production of the signaling molecule hydrogen sulfide, deregulation of which is known to contribute to a range of serious pathological states. Involvement of hydrogen sulfide in pathways of paramount importance for cellular homeostasis renders CBS a promising drug target. An in-house focused library of heteroaromatic compounds was screened for CBS modulators by the methylene blue assay and a pyrazolopyridine derivative with a promising CBS inhibitory potential was discovered.

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Analyzing the structure of proteins from extremophiles is a promising way to study the rules governing the protein structure, because such proteins are results of structural and functional optimization under well-defined conditions. Studying the structure of chitinases addresses an interesting aspect of enzymology, because chitin, while being the world's second most abundant biopolymer, is also a recalcitrant substrate. The crystal structure of a thermostable chitinase from (Chi40) has been solved revealing a β/α-barrel (TIM-barrel) fold with an α+β insertion domain.

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Consensus-based protein engineering strategy has been applied to various proteins and it can lead to the design of proteins with enhanced biological performance. Histone-like HUs comprise a protein family with sequence variety within a highly conserved 3D-fold. HU function includes compacting and regulating bacterial DNA in a wide range of biological conditions in bacteria.

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Here, the complete assembly of the MP-1 (ATCC 15381) genome, combining Illumina and long Nanopore reads, is presented. The gapless assembly consists of a 4.7-Mb circular chromosome and a 26-kb plasmid, with a G+C content of 40.

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18α-Glycyrrhetinic acid (18α-GA) is a bioactive triterpenoid that has been shown to activate the nuclear factor (erythroid-derived-2)-like 2 (Nrf2), the main transcription factor that orchestrates the cellular antioxidant response, in both cellular and organismal context. Although various beneficial properties of 18α-GA have been revealed, including its anti-oxidation and anti-aging activity, its possible protective effect against DNA damage has never been addressed. In this study, we investigated the potential beneficial properties of 18α-GA against DNA damage induced by mitomycin C (MMC) treatment.

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Ionizing radiation-induced bystander effects (RIBE) encompass a number of effects with potential for a plethora of damages in adjacent non-irradiated tissue. The cascade of molecular events is initiated in response to the exposure to ionizing radiation (IR), something that may occur during diagnostic or therapeutic medical applications. In order to better investigate these complex response mechanisms, we employed a unified framework integrating statistical microarray analysis, signal normalization, and translational bioinformatics functional analysis techniques.

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γH2AX has emerged in the last 20 years as a central player in the DDR (DNA damage response), with specificity for DSBs (double-strand breaks). Upon the generation of DSBs, γ-phosphorylation extends along megabase-long domains in chromatin, both sides of the damage. The significance of this mechanism is of great importance; it depicts a biological amplification mechanism where one DSB induces the γ-phosphorylation of thousands of H2AX molecules along megabaselong domains of chromatin, that are adjusted to the sites of DSBs.

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Background: Natural oil seeps offer the opportunity to study the adaptation of ecosystems and the associated microbiota to long-term oil exposure. In the current study, we investigated a land-to-sea transition ecosystem called "Keri Lake" in Zakynthos Island, Greece. This ecosystem is unique due to asphalt oil springs found at several sites, a phenomenon already reported 2500 years ago.

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Background/aim: Medulloblastoma (MBL), an archetypal primitive neuroectodermal tumor of the cerebellum, is the most common pediatric central nervous system malignancy representing approximately 20% of all childhood brain tumors. Herein, we report on a new xenotransplantable tumor cell line, derived from a 6-year-old female patient with cerebellar medulloblastoma, and the completele proteome molecular characterization of subsequent tumors from MBL xenotrasplanted mice.

Materials And Methods: Tumors were grown in nude mice as subcutaneous xenografts (MBLX) composed of small round cells with hyperchromatic nuclei and scant cytoplasm.

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Background/aim: Proteomics based on high-resolution mass spectrometry (MS) is the tool of choice for the analysis of protein presence, modifications and interactions, with increasing emphasis on the examination of tumor tissues. Application of MS-based proteomics offers a detailed picture of tumor tissue characteristics, facilitating the appreciation of different tumor entities, whilst providing reliable and fast results for therapeutic marker targeting and prognostic factor assessment. Through use of the high analytical resolution of nano-high-pressure liquid chromatography (nanoHPLC) and the high resolution of an Orbitrap Elite mass spectrometer, the present study aimed to provide knowledge on the proteome of the generally unknown entity of pediatric ependymal tumors.

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Breast cancer cells are suggested to be organized in a hierarchical manner with a subpopulation of stem cells, termed as breast cancer stem cells (BCSCs), which contribute significantly to tumorigenesis, cancer recurrence and metastasis. BCSCs have been demonstrated to exhibit significant resistance to conventional chemo- and radiotherapy. Recent evidence suggests that treatment of breast cancers with radiation or chemotherapy agents induces stem cell-like properties in non-stem cells.

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The histone-like DNA-binding proteins (HU) serve as model molecules for protein thermostability studies, as they function in different bacteria that grow in a wide range of temperatures and show sequence diversity under a common fold. In this work, we report the cloning of the hutth gene from Thermus thermophilus, the purification and crystallization of the recombinant HUTth protein, as well as its X-ray structure determination at 1.7 Å.

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The last 50 years, a variety of archaea and bacteria able to withstand extremely high doses of ionizing radiation, have been discovered. Several lines of evidence suggest a variety of mechanisms explaining the extreme radioresistance of microorganisms found usually in isolated environments on Earth. These findings are discussed thoroughly in this study.

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Streptococcus macedonicus ACA-DC 198 produces the bacteriocin macedocin in milk only under low NaCl concentrations (<1.0%w/v). The thermosensitive plasmid pGh9:ISS1 was employed to generate osmotic stress resistant (osmr) mutants of S.

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Chitinase 60 from the psychrophilic bacterium Moritella marina (MmChi60) is a four-domain protein whose structure revealed flexible hinge regions between the domains, yielding conformations in solution that range from fully extended to compact. The catalytic domain is a shallow-grooved TIM-barrel. Heat-induced denaturation experiments of the wild-type and mutants resulting from the deletions of the two-Ig-like domains and the chitin binding domain reveal calorimetric profiles that are consistent with non-collaborative thermal unfolding of the individual domains, a property that must be associated to the "hinge-regions".

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Efficient radiation therapy is characterized by enhanced tumor cell killing involving the activation of the immune system (tumor immunogenicity) but at the same time minimizing chronic inflammation and radiation adverse effects in healthy tissue. The aim of this study was to identify gene products involved in immune and inflammatory responses upon exposure to ionizing radiation by using various bioinformatic tools. Ionizing radiation is known to elicit different effects at the level of cells and organism i.

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The four-domain structure of chitinase 60 from Moritella marina (MmChi60) is outstanding in its complexity. Many glycoside hydrolases, such as chitinases and cellulases, have multi-domain structures, but only a few have been solved. The flexibility of the hinge regions between the domains apparently makes these proteins difficult to crystallize.

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