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Selenium-binding proteins represent a ubiquitous protein family and recently SBP1 was described as a new stress response regulator in plants. SBP1 has been characterized as a methanethiol oxidase, however its exact role remains unclear. Moreover, in mammals, it is involved in the regulation of anti-carcinogenic growth and progression as well as reduction/oxidation modulation and detoxification. In this work, we delineate the functional potential of certain motifs of SBP in the context of evolutionary relationships. The phylogenetic profiling approach revealed the absence of SBP in the fungi phylum as well as in most non eukaryotic organisms. The phylogenetic tree also indicates the differentiation and evolution of characteristic SBP motifs. Main evolutionary events concern the CSSC motif for which Acidobacteria, Fungi and Archaea carry modifications. Moreover, the CC motif is harbored by some bacteria and remains conserved in Plants, while modified to CxxC in Animals. Thus, the characteristic sequence motifs of SBPs mainly appeared in Archaea and Bacteria and retained in Animals and Plants. Our results demonstrate the emergence of SBP from bacteria and most likely as a methanethiol oxidase.

Zwitterionic surfactants based on 3-(1-alkyl-3-imidazolio) propane-sulfonate ([ImS3-R] where R is octyl or dodecyl) is an emerging and important class of amphiphile due to their relevance as nano reactors for the synthesis of metallic nanoparticles and accelerated acid hydrolysis. The physicochemical properties of such synthesized imidazolium ring-containing zwitterionic surfactants have been characterized by surface tension and small-angle neutron scattering (SANS) techniques. Surface tension measurements were used to calculate several thermodynamic parameters over a range of concentrations and temperatures (298–313 K). The results obtained showed a weak signature representing the critical micelle concentration (CMC) for ImS3-8, however, by increasing the alkyl length of the hydrophobic group to dodecyl, that is, ImS3-8 to ImS3-12, the signature of the CMC was much more evident. As expected, the CMC for ImS3-12 shifted to a lower concentration. An increase in temperature increased the surface activity and decreased the CMC of both zwitterionic surfactants, although the changes were small. Compared to classical surfactants, that is, sodium dodecyl sulfate and dodecyl trimethylammonium bromide, the CMC of ImS3-12 is much lower. Modeling of SANS data demonstrated that the morphology of the micelles formed by these amphiphiles may be described by the “classical” model, a central hydrophobic core, with a shell of hydrated headgroups. Due to their widespread applications in colloidal and interfacial science, the present study adds new insight to the fundamental understanding of these interesting imidazolium-based surface-active ionic liquids (ImS3-R).

WD40-repeat-containing proteins (WDRs) are highly abundant in all eukaryotes. Several have been implicated as subunits of multi-protein CRL E3 ligase complexes that regulate ubiquitination mediated protein degradation and thus various cellular and developmental processes. Impairment of the WDR protein ULCS1 from Arabidopsis causes pleiotropic phenotypes during plant development, including reduced lignification, anther indehiscence, and sterility. Here we show that RNAi-mediated downregulation of ULCS1 results in a fast-growing phenotype during vegetative development. Due to accelerated growth, ulcs1i mutants reach their vegetative to reproductive transition point earlier than WT plants. However, their comparable germination rate and their similar number of secondary branches and rosette leaves at bolting indicate that ulcs1i is not an early flowering time mutant. GUS staining of progeny, obtained from crosses between ulcs1i and CYCB1::GUS plants, revealed an increased number of mitotic cell divisions in the root meristems of ulcs1i compared to WT. Immunolabeling of homogalacturonans (HGAs) epitopes showed significant fluorescent signal differences at the cell walls and the mucilage of the seeds between ulcs1i and WT. Furthermore, we demonstrate that ULCS1 interacts with the UBA-like protein in a yeast two-hybrid assay, suggesting a direct or indirect physical coupling of these proteins in Arabidopsis.

Selenium-binding proteins (SBPs) represent a ubiquitous protein family implicated in various environmental stress responses, although the exact molecular and physiological role of the SBP family remains elusive. In this work, we report the identification and characterization of CrSBD1, an SBP homolog from the model microalgae Chlamydomonas reinhardtii. Growth analysis of the C. reinhardtii sbd1 mutant strain revealed that the absence of a functional CrSBD1 resulted in increased growth under mild oxidative stress conditions, although cell viability rapidly declined at higher hydrogen peroxide (H2O2) concentrations. Furthermore, a combined global transcriptomic and metabolomic analysis indicated that the sbd1 mutant exhibited a dramatic quenching of the molecular and biochemical responses upon H2O2-induced oxidative stress when compared to the wild-type. Our results indicate that CrSBD1 represents a cell regulator, which is involved in the modulation of C. reinhardtii early responses to oxidative stress. We assert that CrSBD1 acts as a member of an extensive and conserved protein–protein interaction network including Fructose-bisphosphate aldolase 3, Cysteine endopeptidase 2, and Glutaredoxin 6 proteins, as indicated by yeast two-hybrid assays.

AtRD19c is a member of the papain-like cysteine proteases known for its participation in anther development after its maturation by βVPE (vacuolar processing enzyme). This papain-like cysteine protease was identified as an interacting protein of AtSBP1 (selenium binding protein 1) in a yeast two-hybrid screening. To confirm this interaction, we studied AtRD19c with respect to its expression and ability to interact with AtSBP1. The highest gene expression levels of AtRD19c were observed in the roots of 10-day-old seedlings, whereas minimum levels appeared in the hypocotyls of 10-day-old seedlings and flowers. AtRD19c expression was upregulated by selenium, and analysis of its promoter activity showed colocalization of a reporter gene (GUS) with AtSBP1. Additionally, the AtRD19c expression pattern was upregulated in the presence of selenite, indicating its participation in the Se response network. Confocal fluorescence microscopy revealed that AtRD19c localizes in the root tip, lateral roots, and leaf trichomes. Finally, we confirmed the physical interaction between AtRD19c and AtSBP1 and showed the importance of the first 175 aa of the AtSBP1 polypeptide in this interaction. Importantly, the AtRD19c-AtSBP1 interaction was also demonstrated in planta by employing bimolecular fluorescent complementation (BiFC) in a protoplast system. © 2021 Elsevier B.V.

WD40-repeat-containing proteins (WDRs) are highly abundant in all eukaryotes. Several have been implicated as subunits of multi-protein CRL E3 ligase complexes that regulate ubiquitination mediated protein degradation and thus various cellular and developmental processes. Impairment of the WDR protein ULCS1 from Arabidopsis causes pleiotropic phenotypes during plant development, including reduced lignification, anther indehiscence, and sterility. Here we show that RNAi-mediated downregulation of ULCS1 results in a fast-growing phenotype during vegetative development. Due to accelerated growth, ulcs1i mutants reach their vegetative to reproductive transition point earlier than WT plants. However, their comparable germination rate and their similar number of secondary branches and rosette leaves at bolting indicate that ulcs1i is not an early flowering time mutant. GUS staining of progeny, obtained from crosses between ulcs1i and CYCB1::GUS plants, revealed an increased number of mitotic cell divisions in the root meristems of ulcs1i compared to WT. Immunolabeling of homogalacturonans (HGAs) epitopes showed significant fluorescent signal differences at the cell walls and the mucilage of the seeds between ulcs1i and WT. Furthermore, we demonstrate that ULCS1 interacts with the UBA-like protein in a yeast two-hybrid assay, suggesting a direct or indirect physical coupling of these proteins in Arabidopsis.

WD40-repeat-containing proteins (WDRs) are highly abundant in all eukaryotes. Several have been implicated as subunits of multi-protein CRL E3 ligase complexes that regulate ubiquitination mediated protein degradation and thus various cellular and developmental processes. Impairment of the WDR protein ULCS1 from Arabidopsis causes pleiotropic phenotypes during plant development, including reduced lignification, anther indehiscence, and sterility. Here we show that RNAi-mediated downregulation of

AtRD19c is a member of the papain-like cysteine proteases known for its participation in anther development after its maturation by βVPE (vacuolar processing enzyme). This papain-like cysteine protease was identified as an interacting protein of AtSBP1 (selenium binding protein 1) in a yeast two-hybrid screening. To confirm this interaction, we studied AtRD19c with respect to its expression and ability to interact with AtSBP1. The highest gene expression levels of AtRD19c were observed in the roots of 10-day-old seedlings, whereas minimum levels appeared in the hypocotyls of 10-day-old seedlings and flowers. AtRD19c expression was upregulated by selenium, and analysis of its promoter activity showed colocalization of a reporter gene (GUS) with AtSBP1. Additionally, the AtRD19c expression pattern was upregulated in the presence of selenite, indicating its participation in the Se response network. Confocal fluorescence microscopy revealed that AtRD19c localizes in the root tip, lateral roots, and leaf trichomes. Finally, we confirmed the physical interaction between AtRD19c and AtSBP1 and showed the importance of the first 175 aa of the AtSBP1 polypeptide in this interaction. Importantly, the AtRD19c-AtSBP1 interaction was also demonstrated in planta by employing bimolecular fluorescent complementation (BiFC) in a protoplast system.

During abiotic stress the primary symptom of phytotoxicity can be ROS production which is strictly regulated by ROS scavenging pathways involving enzymatic and non-enzymatic antioxidants. Furthermore, ROS are well-described secondary messengers of cellular processes, while during the course of evolution, plants have accomplished high degree of control over ROS and used them as signalling molecules. Glutaredoxins (GRXs) are small and ubiquitous glutathione (GSH) -or thioredoxin reductase (TR)-dependent oxidoreductases belonging to the thioredoxin (TRX) superfamily which are conserved in most eukaryotes and prokaryotes. In Arabidopsis thaliana GRXs are subdivided into four classes playing a central role in oxidative stress responses and physiological functions. In this work, we describe a novel interaction of AtGRXS14 with the Selenium Binding Protein 1 (AtSBP1), a protein proposed to be integrated in a regulatory network that senses alterations in cellular redox state and acts towards its restoration. We further show that SBP protein family interacts with AtGRXS16 that also contains a PICOT domain, like AtGRXS14.

Οι πρωτεΐνες που δεσμεύουν σελήνιο (SBPs) είναι πρωτεΐνες με πολύ υψηλή συντήρηση και παρούσες σε όλα τα βασίλεια της ζωής. Στον άνθρωπο, οι μελέτες είναι πολυάριθμες και η σημασία τους στη διαδικασία ανάπτυξης κακοηθειών είναι ήδη γνωστή. Στους φυτικούς οργανισμούς έχει φανεί η συμμετοχή της SBP1 στην αντιμετώπιση βιοτικών και αβιοτικών καταπονήσεων. Προηγούμενες μελέτες έχουν αποκαλύψει την πιθανή ικανότητα της SBP1 να αλληλεπιδρά με δεκατέσσερις στο σύνολό τους πρωτεΐνες που σχετίζονται με την μεταφορά πρωτεϊνών μέσω κυστιδίων, την μεμβρανική σύνθεση και τον οξειδωτικό έλεγχο του κυττάρου, υποδεικνύοντας την συμμετοχή της σε ένα νέο πρωτεϊνικό δίκτυο που σχετίζεται με την οξειδωτική καταπόνηση. Σκοπός της συγκεκριμένης διατριβής ήταν η επιβεβαίωση της ύπαρξης του πρωτεϊνικού δικτύου της SBP1 μέσω της μελέτης των πιθανών αλληλεπιδρωσών πρωτεϊνών και της διερεύνησης των αλληλεπιδράσεών τους με αυτή. Έτσι, μελετήθηκαν λεπτομερώς δυο πρωτεΐνες που σχετίζονται με την μεταφορά πρωτεϊνών μέσω κυστιδίων (RD19c) και με την μεμβρανική σύνθεση (DALL3), ενώ μελετήθηκαν και άλλες τρεις πρωτεΐνες (GRXS14, GRXS16, SAH7) ως προς την ικανότητα τους να αλληλεπιδρούν με την SBP1. Η φωσφολιπάση και η πρωτεάση μελετήθηκαν ως προς την ιστοειδική τους έκφραση, όπου η πρώτη εντοπίστηκε στον αγωγό ιστό της ρίζας, στα υδατόδια, στα καταφρακτικά κύτταρα και στο αγγειακό σύστημα των κοτυληδόνων και των πρώτων φύλλων, στο αγωγό σύστημα των ανθήρων, των πετάλων και των κερατίων και στο στίγμα, ενώ η δεύτερη στα καταφρακτικά κύτταρα, στα υδατόδια των κοτυληδόνων και των πρώτων φύλλων, στις τρίχες των πρώτων φύλλων, στον αγωγό ιστό της ρίζας και των πλάγιων ριζών, των πρώτων φύλλων και των κοτυληδόνων, των πετάλων και των ανθήρων καθώς και στη βάση των κερατίων και στους γυρεόκοκκους. Με αυτό τον τρόπο δείχτηκε ότι τα μετάγραφα της DALL3 και της RD19c επάγονται στους ίδιους ιστούς με αυτούς της SBP1, όπως είναι το στίγμα, τα καταφρακτικά κύτταρα και η ρίζα. Επιπλέον, με την μελέτη του υποκυτταρικού τους εντοπισμού ανιχνεύθηκαν η φωσφολιπάση στα πλαστίδια που περιβάλλουν τον αγωγό ιστό και σε αυτά της ακραίας περιοχής της ρίζας, στις πλάγιες ρίζες και στους χλωροπλάστες των καταφρακτικών κυττάρων. Αντίστοιχα, η πρωτεάση εντοπίστηκε στην ακραία περιοχή της κεντρικής ρίζας και των πλάγιων ριζών αλλά και στις τρίχες των πρώτων φύλλων. Ως προς τα επίπεδα έκφρασης, εκτός από αυτές τις πρωτεΐνες, μελετήθηκε και το αλλεργιογόνο SAH7. Παρατηρήθηκε μια συνεχή έκφραση και για τις τρεις πρωτεΐνες με την φωσφολιπάση να έχει μέγιστο στον ιστό της ρίζας αρτιβλάστων 10 ημερών και στα άνθη και ελάχιστο στα αρτίβλαστα 10 ημερών και στα φύλλα ροζέτας. Η πρωτεάση παρουσίασε υψηλότερα επίπεδα έκφρασης στη ρίζα χωρίς όμως στατιστικά σημαντική διαφορά και χαμηλότερα στα άνθη και στα φύλλα ροζέτας, ενώ η SAH7 είχε μέγιστο στις κοτυληδόνες και στο βλαστό αρτιβλάστων 10 ημερών και ελάχιστο στα φύλλα ροζέτας. Επιπρόσθετα, μελετήθηκαν και ως προς την επαγωγή τους στην παρουσία σεληνώδους, σεληνικού και καδμίου, όπου και οι τρεις παρουσίασαν αυξημένα επίπεδα παρουσία σεληνώδους, υποδεικνύοντας την συμμετοχή τους στον μηχανισμό απόκρισης τουλάχιστον αυτής της μορφής σεληνίου. Ο αρχικός έλεγχος των αλληλεπιδράσεων πραγματοποιήθηκε στο σύστημα ζύμης δύο υβριδίων, όπου αποκαλύφθηκε η αλληλεπίδραση και των τεσσάρων πρωτεϊνών που ελέγχθηκαν με την SBP1. Στο ίδιο σύστημα δείχθηκε ότι τα πρώτα 175 αμινοξικά κατάλοιπα της SBP1 είναι απαραίτητα για την αλληλεπίδρασή της με την DALL3 και την RD19c, ενώ τα πρώτα 105 για την αλληλεπίδρασή της με την γλουταρεδοξίνη 14 και το αλλεργιογόνο SAH7. Τέλος, εντοπίστηκε η πρωτεάση RD19c σε κυστίδια, η φωσφολιπάση DALL3 σε δομές που εφάπτονται στους χλωροπλάστες και στα πλαστίδια της ρίζας, τις γλουταρεδοξίνες GRXS14 και GRXS16 στους χλωροπλάστες, το αλλεργιογόνο SAH7 στο ενδοπλασματικό δίκτυο και την SBP1 στον πυρήνα και το κυτταρόπλασμα. Παρά τον διαφορετικό τους υποκυτταρικό εντοπισμό αποκαλύφθηκε ότι οι αλληλεπιδράσεις πραγματοποιούνται in planta. H SBP1 αλληλεπιδρά με την DALL3 σε δομές που εφάπτονται στους χλωροπλάστες, με την RD19c στο κυτταρόπλασμα, την GRXS14 στο κυτταρόπλασμα και τον πυρήνα, ενώ με την GRXS16 μόνο στο κυτταρόπλασμα και τέλος με το SAH7 στο ενδοπλασματικό δίκτυο. Η SBP1 έχει βρεθεί ότι συμμετέχει στις διαδικασίες αποτοξίνωσης του φυτού από την οξειδωτική καταπόνηση και από στην παρούσα διατριβή επιβεβαιώθηκε η ύπαρξη του νέου πρωτεϊνικού δικτύου της SBP1, στο οποίο έχει κυρίαρχο ρόλο και σχετίζεται με την απόκριση του φυτού στην οξειδωτική καταπόνηση. Selenium binding proteins (SBPs) are highly conserved and have representatives in all life kingdoms. In humans, many studies have demonstrated SBP1 importance in cancer development. In plants, SBP1 participates in biotic and abiotic stress responses. Previous studies have revealed its ability to interact with 14 proteins related to protein trafficking, membrane synthesis and redox control, indicating its participation in a novel protein network linked to oxidative stress. The aim of this thesis was to confirm the existence of the SBP1 network by studying the interacting proteins in the model plant Arabidopsis thaliana. Thus, two proteins related to protein trafficking (RD19c) and membrane synthesis (DALL3) were studied, while GRXS14, GRXS16 and SAH7 were additionally investigated for their ability to interact with SBP1. The phospholipase DALL3 and the protease RD19c were initially studied for tissue-specific expression, with the first one expressed in the root cylinder, hydothodes, guard cells, vasculature of cotyledons, first emerging leaves, sepals, siliques and anthers and in the stigma, while RD19c was expressed in guard cells, hydothodes, leaf trichomes, vasculature tissues of roots, lateral roots, first emerging leaves, cotyledons, sepals, anthers as well as in the silique base and in pollen. In these analyses it was shown that the transcipts of DALL3 and RD19c are expressed in the same tissues with those of SBP1, such as guard cells, stigma and root. Moreover, in subcellular analysis the phospholipase DALL3 was detected in the chloroplasts of the guard cells, in plastids of the root apex and the central root and in the lateral root primordia. Similarly, the protease localized in the root apex of the central and lateral roots and leaf trichomes. The relative expression levels were studied also in the allergen SAH7. The expression levels of these proteins were constitutive, with the highest expression in 10-day-old roots and flowers for DALL3 and minimum in 10-days-old seedlings and rosette leaves. The protease exhibited its highest expression levels in roots with no statistical significance difference and the lowest expression was in flowers and rosette leaves, while SAH7 was upregulated in cotyledons and shoots and downregulated in rosette leaves. Furthermore, the respective genes were studied for their induction in the presence of selenite, selenate and cadmium, and were highly expressed after selenite treatment, indicating their participation in the response mechanism related at least to this chemical compound. The initial investigation of protein-protein interactions was accomplished in yeast two-hybrid assay, which revealed the interaction of the four proteins with SBP1. In the same system, it was showed that the first 175 amino acids of SBP1 are crucial for its interaction with the DALL3 and RD19c, whereas the 105 with the GRXS14 and SAH7. Finally, the protease RD19c was detected in vesicles, the phospholipase DALL3 in speckle-like structures attached to chloroplasts and in root plastids, the gloutaredoxins GRXS14 and GRXS16 in chloroplasts, the allergen SAH7 in the endoplasmic reticulum and the SBP1 in cytoplasm and nucleus. Despite their different subcellular localization we revealed that these interactions can take place in planta. SBP1 interacts with the DALL3 in speckle-like structures attached to the chloroplasts and in root plastids, with the RD19c in cytoplasm, GRXS14 in the cytoplasm and nucleus, GRXS16 only in cytoplasm and lastly SAH7 in the endoplasmic reticulum. SBP1 is known for its participation in plant detoxification procedures against oxidative stress and our study confirms the existence of a novel protein network, where SBP1 exhibits the main role and is related to plant responses against oxidative stress.

Healthcare is a complex system with many actors involved such as Patient, General Practitioner, Hospital, and Pharmacy. The focus is on the Patient, however, actors collaborate to deliver the best healthcare service to the patient. Each of the elements of the healthcare system is a separate complicated system. This paper proposed a patient-centric smart healthcare information system (PCSHIS) integrates and orchestrates Patient Records Repository, General Practitioner Information System, Pharmacy Information System, and Hospital Information System to optimize the expenses of health service delivery and to ensure the best possible healthcare. All systems are built and integrated into a prototype PCSHIS with a software platform for building applications dOS of dWare company.

Phospholipase PLA1-Iγ2 or otherwise DAD1-LIKE LIPASE 3 (DALL3) is a member of class I phospholipases and has a role in JA biosynthesis. AtDALL3 was previously identified in a yeast two-hybrid screening as an interacting protein of the Arabidopsis Selenium Binding Protein 1 (SBP1). In this work, we have studied AtDALL3 as an interacting partner of the Arabidopsis Selenium Binding Protein 1 (SBP1). Phylogenetic analysis showed that DALL3 appears in the PLA1-Igamma1, 2 group, paired with PLA1-Igammma1. The highest level of expression of AtDALL3 was observed in 10-day-old roots and in flowers, while constitutive levels were maintained in seedlings, cotyledons, shoots and leaves. In response to abiotic stress, DALL3 was shown to participate in the network of genes regulated by cadmium, selenite and selenate compounds. DALL3 promoter driven GUS assays revealed that the expression patterns defined were overlapping with the patterns reported for AtSBP1 gene, indicating that DALL3 and SBP1 transcripts co-localize. Furthermore, quantitative GUS assays showed that these compounds elicited changes in activity in specific cells files, indicating the differential response of DALL3 promoter. GFP::DALL3 studies by confocal microscopy demonstrated the localization of DALL3 in the plastids of the root apex, the plastids of the central root and the apex of emerging lateral root primordia. Additionally, we confirmed by yeast two hybrid assays the physical interaction of DALL3 with SBP1 and defined a minimal SBP1 fragment that DALL3 binds to. Finally, by employing bimolecular fluorescent complementation we demonstrated the in planta interaction of the two proteins. © 2019 Elsevier B.V.

Phospholipase PLA1-Iγ2 or otherwise DAD1-LIKE LIPASE 3 (DALL3) is a member of class I phospholipases and has a role in JA biosynthesis. AtDALL3 was previously identified in a yeast two-hybrid screening as an interacting protein of the Arabidopsis Selenium Binding Protein 1 (SBP1). In this work, we have studied AtDALL3 as an interacting partner of the Arabidopsis Selenium Binding Protein 1 (SBP1). Phylogenetic analysis showed that DALL3 appears in the PLA1-Igamma1, 2 group, paired with PLA1-Igammma1. The highest level of expression of AtDALL3 was observed in 10-day-old roots and in flowers, while constitutive levels were maintained in seedlings, cotyledons, shoots and leaves. In response to abiotic stress, DALL3 was shown to participate in the network of genes regulated by cadmium, selenite and selenate compounds. DALL3 promoter driven GUS assays revealed that the expression patterns defined were overlapping with the patterns reported for AtSBP1 gene, indicating that DALL3 and SBP1 transcripts co-localize. Furthermore, quantitative GUS assays showed that these compounds elicited changes in activity in specific cells files, indicating the differential response of DALL3 promoter. GFP::DALL3 studies by confocal microscopy demonstrated the localization of DALL3 in the plastids of the root apex, the plastids of the central root and the apex of emerging lateral root primordia. Additionally, we confirmed by yeast two hybrid assays the physical interaction of DALL3 with SBP1 and defined a minimal SBP1 fragment that DALL3 binds to. Finally, by employing bimolecular fluorescent complementation we demonstrated the in planta interaction of the two proteins.

During abiotic stress the primary symptom of phytotoxicity can be ROS production which is strictly regulated by ROS scavenging pathways involving enzymatic and non-enzymatic antioxidants. Furthermore, ROS are well-described secondary messengers of cellular processes, while during the course of evolution, plants have accomplished high degree of control over ROS and used them as signalling molecules. Glutaredoxins (GRXs) are small and ubiquitous glutathione (GSH) -or thioredoxin reductase (TR)-dependent oxidoreductases belonging to the thioredoxin (TRX) superfamily which are conserved in most eukaryotes and prokaryotes. In Arabidopsis thaliana GRXs are subdivided into four classes playing a central role in oxidative stress responses and physiological functions. In this work, we describe a novel interaction of AtGRXS14 with the Selenium Binding Protein 1 (AtSBP1), a protein proposed to be integrated in a regulatory network that senses alterations in cellular redox state and acts towards its restoration. We further show that SBP protein family interacts with AtGRXS16 that also contains a PICOT domain, like AtGRXS14. © 2019 Elsevier B.V.

Quality characteristics of olive products significantly depend on cultivar (cv), among other factors. In this study, seven traditional, noncommercial Greek cultivars, along with the commercial Spanish Arbequina cv., were examined for the phenolic antioxidant dynamic of their leaves. Polar extracts (aqueous, methanol, and ethanol) were analyzed for Total Phenol (TP), Flavonoid (TFL), Hydroxycinnamic Acid Derivatives (THAD), Flavonol (TFLVN) contents, DPPH radical scavenging ability, and Ferric Reducing Capacity (FRAP). Selective characteristics of olive leaf methanol extracts for all cultivars were re-examined on a second sampling period. Olive leaf is considered a rich source of phenolic antioxidants total phenol content reaching 29.3 &plusmn, 1.3, 30.6 &plusmn, 0.4, and 27.0 &plusmn, 1.1 mg caffeic acid/g dry leaf for aqueous, methanol, and ethanol extracts, respectively) and all cultivars were considered of equal bioactive dynamic. TP data derived from Folin&ndash, Ciocalteu and another spectrophotometric assay employed presented a high correlation for all examined cases (R2 = 71.5&ndash, 86.9%). High correlation (R2 = 0.92) was also found between TP and FRAP findings of aqueous extracts. Olive leaf is considered a promising source of phenolic antioxidants irrelevant to cultivar and therefore even cultivars less effective for oil or table olive production could be efficiently exploited for the bioactive dynamic of their leaves.

A systematic study of the cellular uptake of emissive complexes as a function of their lipophilicity is presented. Here a series of amphiphilic rhenium fac-tricarbonyl bisimine complexes bearing axial substituted imidazole or thiazole ligands, [Re(bpy)(CO)3(ImCnHm)]+ {n = 1 m = 3 (1+), n = 4 m = 9 (2+), n = 8 m = 17 (3+), n = 12 m = 25 (4+), n = 16 m = 33 (5+), n = 2 m = 3 (6+); bpy = 2,2'-bipyridine, Im = imidazole} and [Re(bpy)(CO)3(L)]+ {L = 1-mesitylimidazole, ImMes (7+), 4,5-dimethylthiazole, dmt (8+) and 4-methyl-5-thiazole-ethanol, mte (9+)} is reported. The X-ray crystal structures of 2+, 8+ and 9+ confirm the geometry and expected distribution of ligands and indicated that the plane of the imidazole/thiazole ring is approximately parallel to the long axis of the bipy ligand. Luminescence studies revealed excellent properties for their use in cell imaging with visible excitation and broad emission profiles. Their uptake in two distinct species has been examined by fluorescence imaging of the diplomonad fish parasite Spironucleus vortens (S. vortens) and rod-shaped yeast Schizosaccharomyces pombe (Schiz. pombe) as a function of their lipophilicity. The uptake of the complexes was highest for the more lipophilic 2+-5+ in both S. vortens and Schiz. pombe in which the long alkyl chain aids in crossing bilipid membranes. However, the increased lipophilicity of longer chains also resulted in greater toxicity. Localisation over the whole cell varied with differing alkyl chain lengths with complex 2+ preferentially locating to the nucleus of S. vortens, 3+ showing enhanced nuclear partitioning in Schiz. pombe, and 4+ for the remaining cell wall bound in the case of S. vortens. Interestingly, complexes of intermediate lipophilicity such as 7+ and 8+ showed reasonable uptake, proved to be non-toxic, and were capable of crossing exterior cell walls and localising in the organelles of the cells.

Η φωσφολιπάση Α1, PLA1-Iγ2 (AT2G30550, DAD1-like lipase 3 ή DALL3) είναι μια χλωροπλαστιδιακή πρωτεΐνη και ανήκει στην οικογένεια λιπασών DAD1-like lipase λόγω ομοιοτήτων στην αμινοξική αλληλουχία της καταλυτικής περιοχής με την πρωτεΐνη DAD1. Η φωσφολιπάση PLA1-Iγ2 (DALL3) συμμετέχει στο μονοπάτι βιοσύνθεσης του ιασμονικού και επιπλέον σχετίζεται με αποκρίσεις σε βιοτικές και αβιοτικές καταπονήσεις. Επίσης, πιθανόν αλληλεπιδρά με τις πρωτεΐνες που δεσμεύουν σελήνιο (SBP, Selenium-Binding Proteins). Για να διερευνηθεί η πιθανή κοινή ιστοειδική παρουσία, της PLA1-Iγ2 και των SBP, έγινε μελέτη της πρωτεΐνης PLA1-Iγ2, μέσω της ιστοειδικής μελέτης της έκφρασης του γονιδίου PLA1-Iγ2. Για το σκοπό αυτό επιλέχθηκε μια αλληλουχία, μεγέθους 2.430bp, ανοδικά του σημείου έναρξης της αντιγραφής του γονιδίου και μια απαλοιφή του 5’-άκρου του, μεγέθους 1.571bp, και ακολούθησε η δημιουργία διαγονιδιακών GUS φυτών, με τη δημιουργία κατασκευών που περιέχουν αυτές τις αλληλουχίες σε μεταγραφική σύντηξη με το γονίδιο αναφοράς GUS. Παρατηρήθηκε αλλαγή στο πρότυπο έκφρασης μεταξύ των δύο κατασκευών, λόγω της παρουσίας ρυθμιστικών στοιχείων που σχετίζονται με το φως. Επίσης, μελετήθηκε το επίπεδο έκφρασης του γονιδίου PLA1-Iγ2, μέσω ημιποσοτικής αλυσιδωτής αντίδρασης αντίστροφης μεταγραφής σε διάφορα αναπτυξιακά στάδια και ιστούς, όπου παρατηρήθηκε η συνεχής έκφρασή του με μέγιστο στις κοτυληδόνες αρτιβλάστων 10 ημερών. Τέλος, μέσω της μελέτης των επιπέδων έκφρασης του γονιδίου υπό αβιοτικές συνθήκες καταπόνησης, παρατηρήθηκε αύξηση της έκφρασης κατά την παρουσία τετρασθενούς σεληνίου (SeIV) και μείωση της έκφρασης με την παρουσία εξασθενούς σεληνίου (SeVI). Τα στοιχεία αυτά ενισχύουν την πιθανή κοινή ιστοειδική παρουσία των δύο πρωτεϊνών. Phospholipase A1, PLA1-Iγ2 (AT2G30550, DAD1-like lipase 3 or DALL3) is a chloroplastic protein, which shares similarities in the aminoacid sequence of the catalytic region of DAD1. Hence, phospholipase A1 belongs to a major protein family called DAD1-like lipase. PLA1-Ιγ2 (DALL3) is involved in the biosynthesis pathway of jasmonic acid and is also related to responses to biotic and abiotic stress. In the present study we investigated the tissue specific expression of PLA1-Iγ2. An upstream sequence of 2430bp and its 5' end deletion (1571bp) were selected for the engineering of transgenic GUS plants. This has been accomplished through transcriptional fusion of the aforementioned sequences with the GUS reporter gene. A change in the pattern of expression was between the two transgenic constructs, which is attributed to regulatory elements related to light. Additionally, the level of expression of PLA1-Iγ2 gene was measured by semi-quantitive RT-PCR in various tissues and developmental stages. Ubiquitous expression was observed with a maximum occurring in cotyledon leaves of 10 day old seedlings. While studying the PLA1-Iγ2 level of expression under abiotic stress, we observed upregulation of PLA1-Iγ2 in the presence of Selenite (SeIV), whereas downregulation was recorded in the presence of Selenate (SeVI). Our results present further evidence in support of the proposed interaction and common tissue specific expression of PLA1-Iγ2 and SBPs.

In body-centric communications, energy efficiency is a critical performance metric, while the achievable data rate is not of primary concern. In this paper we present a novel modulation scheme, which can be efficiently used in body-centric terahertz (THz) nanonetworks. The proposed scheme is a combination of the time-spread On-Off keying (TS–OOK) and the pulse position modulation (PPM) and presents lower energy consumption, compared to other existing methods as TS–OOK, at a minor cost to the data rate. Furthermore, another important aspect is that the proposed modulation scheme can be effectively used to mitigate the impact of the specific kind of noise in THz body-centric communications, thus leading to better error performance. Finally, we present analytical and simulation results in order to compare the new scheme with the existing TS–OOK.

Wir betrachten eine Gruppe von stochastischen Volatilit��tsmodellen, f��r welche die Momente der Inkremente eine ungew��hnliche Skalierung, eine Form des sogenannten Multiscaling, zeigen. Sie verhalten sich asymptotisch f��r kleine Intervalle wie Potenzen der Intervalll��nge, wobei der Exponent eine nichtlineare Funktion der Ordnung der Momente ist. Wir interessieren uns f��r die Gruppe von Modellen, die k��rzlich von Andreoli, Caravenna, Dai Pra, und Posta eingef��hrt wurden. Ausgangspunkt sind logarithmische Returns, die als stochastische Integrale bez��glich einer Brownscher Bewegung modelliert werden, die Volatilit��t ist ein Ornstein-Uhlenbeck-Prozess, der von einem Subordinator angetrieben wird. In diesem Fall gibt es kein Multi-Scaling. Ersetzt man den Drift-Term im Ornstein-Uhlenbeck-Prozess durch eine superlineare Funktion der Volatilit��t entsteht Multiscaling. Durch eine genaue Analyse und Fallunterscheidugen werden konkrete Formeln f��r die entsprechenden Exponenten hergeleitet., We consider a group of stochastic volatility models, that exhibit an unusual scaling behaviour, which is called multi-scaling. They behave asymptotically like powers of the interval length, where the exponent is a non-linear function of the order of the moments. We are in particular interested in a group of models introduced recently by Andreoli, Caravenna, Dai Pra, and Posta. Starting point are logarithmic returns, that are modeled as stochastic integrals with respect to a Brownian motion. The volatility is an Ornstein-Uhlenbeck-type process driven by a subordinator. In this case there is no multi-scaling. If we replace the drift term in the Ornstein-Uhlenbeck equation by a superlinear function of the volalitility we obtain multi-scaling. A careful and detailed anaysis and distinction of cases we obtain explicit formulas for the corresponding exponents.

Cationic Ir(III) systems supported by a bis(expanded NHC) framework and featuring both agostic C-H and cis alkyl/hydride ligand sets have been targeted by protonation of the corresponding bis(alkyl) hydride complexes. Remarkably, the steric shielding afforded by the NHC substituents is such that these and related putative 14-electron cations are air and moisture stable. In solution, degenerate fluxional exchange is brought about by reversible σ-bond activation within the agostic alkyl C(sp3)-H bond; a non-dissociative mechanism is implied by the activation parameters ΔH‡ = 8.8(0.4) kcal mol-1 and ΔS‡ = -12.2(1.7) eu. © 2012 American Chemical Society.

The synthesis and silver(I) and gold(I) coordination chemistry of a new chiral, bidentate N-heterocyclic carbene (NHC) dehydrohexitol derivative (3) are reported. The imidazolium salt [H23][PF6]2 reacts with Ag2O and Au(tht)Cl (tht = tetrahydrothiophene) precursors to form the isostructural 18-membered metallamacrocyclic dimers [Ag2(μ-3)2][PF6]2 and [Au2(μ-3)2][PF6]2 and the monocarbene complex [(AuCl)2(μ-3)]. Single-crystal X-ray structures have been determined for the bis-imidazolium precursor [H23][PF6]2 and corresponding Ag(I) and Au(I) complexes of ligand 3. Comparison between the X-ray-derived structures and solution-phase NMR data for [Ag2(μ-3)2][PF6]2 and [Au2(μ-3)2]- [PF6]2 demonstrate that the complexes adopt a conformation in solution different from that found in the solid state, implying a conformational flexibility of the metallamacrocycle in solution. Both [(AuCl)2(μ-3)] and [Au2(μ-3)2][PF6]2 are emissive in the solid state at ca. 380 nm (λex = 295 nm). Time-resolved luminescence measurements indicate different excited-state lifetimes for the two species, with [(AuCl)2(μ-3)] measured at 35 ns and [Au2(μ-3)2][PF6]2 at 379 ns. The chiroptical properties of the silver and goldNHCcomplexes have been studied by circular dichroism (CD).