Expression and Localization of Glycosaminoglycans/Proteoglycan in Pterygium: An Immunohistochemical Study

Pterygium is a triangle-shaped fibrovascular hyperplasia of the bulbar conjunctiva on the cornea. The purpose of this study was to analyze Proteoglycans (PGs) by Immunohistochemistry (IHC) in pterygium tissues and to compare the results with normal conjunctiva. Twenty-four patients (14 males) undergoing primary pterygium excision and 17 healthy individuals (10 males), undergoing extracapsular cataract surgery, were included. Pterygium tissues and normal conjunctiva tissues were surgically removed. The tissue sections were fixed in 2% paraformaldehyde and incubated with monoclonal antibodies against PGs anti-mouse IgG. Immunohistochemical study showed stronger expression of keratan sulfate in the stroma of the pterygium compared to normal conjunctiva. An increased expression of heparan sulfate was observed in the epithelial layer and around the pterygium vessels. On the other hand, dermatan sulfate showed an increased expression and localization not only in the sub-epithelial area of the pterygium and normal conjunctiva, yet throughout the stroma of the pterygium. The differences in the expression and localization of the studied extracellular matrix proteoglycans in the pterygium tissue compared to normal conjunctiva may explain the tissue hyperplasia, structure, and the functional properties in pterygium

Расчет, проектирование и монтаж каркаса автостоянки открытого типа

Актуальность работы: в данной выпускной квалификационной работе выполняются расчет и проектирование каркаса автостоянки открытого типа. Целью работы является разработка технологии изготовления каркаса. Целью данного курсового проекта является изучение составных частей изделия, определение марки стали, выбор метода сварки, определение режимов сварки и сварочных материалов, нормализация операций, составление технологического процесса, расчет необходимого количества оборудования и работников.Relevance of work: in this final qualification work, the calculation and design of the open-type carcass frame are performed. The aim of the work is to develop a technology for manufacturing a carcass. The objectives of this course project is to study the component parts of a product, determine the grade of steel, choose a welding method, determine welding modes and welding materials, normalize operations, draw up a process, calculate the required amount of equipment and the number of workers

Presenilin1 familial Alzheimer disease mutants inactivate EFNB1- and BDNF-dependent neuroprotection against excitotoxicity by affecting neuroprotective complexes of N-methyl-d-aspartate receptor

Excitotoxicity is thought to play key roles in brain neurodegeneration and stroke. Here we show that neuroprotection against excitotoxicity by trophic factors EFNB1 and brain-derived neurotrophic factor (called here factors) requires de novo formation of 'survival complexes' which are factor-stimulated complexes of N-methyl-D-aspartate receptor with factor receptor and presenilin 1. Absence of presenilin 1 reduces the formation of survival complexes and abolishes neuroprotection. EPH receptor B2- and N-methyl-D-aspartate receptor-derived peptides designed to disrupt formation of survival complexes also decrease the factor-stimulated neuroprotection. Strikingly, factor-dependent neuroprotection and levels of the de novo factor-stimulated survival complexes decrease dramatically in neurons expressing presenilin 1 familial Alzheimer disease mutants. Mouse neurons and brains expressing presenilin 1 familial Alzheimer disease mutants contain increased amounts of constitutive presenilin 1-N-methyl-D-aspartate receptor complexes unresponsive to factors. Interestingly, the stability of the familial Alzheimer disease presenilin 1-N-methyl-D-aspartate receptor complexes differs from that of wild type complexes and neurons of mutant-expressing brains are more vulnerable to cerebral ischaemia than neurons of wild type brains. Furthermore, N-methyl-D-aspartate receptor-mediated excitatory post-synaptic currents at CA1 synapses are altered by presenilin 1 familial Alzheimer disease mutants. Importantly, high levels of presenilin 1-N-methyl-D-aspartate receptor complexes are also found in post-mortem brains of Alzheimer disease patients expressing presenilin 1 familial Alzheimer disease mutants. Together, our data identify a novel presenilin 1-dependent neuroprotective mechanism against excitotoxicity and indicate a pathway by which presenilin 1 familial Alzheimer disease mutants decrease factor-depended neuroprotection against excitotoxicity and ischaemia in the absence of Alzheimer disease neuropathological hallmarks which may form downstream of neuronal damage. These findings have implications for the pathogenic effects of familial Alzheimer disease mutants and therapeutic strategies.This work was supported by National Institutes of Health grants 2RF1AG008200-29; 2R01-NS047229; P50AG05138; and by Grant AARF-17-531426 of the Alzheimer's Association

Phenyl Bis-Sulfonamide Keap1-Nrf2 Protein–Protein Interaction Inhibitors with an Alternative Binding Mode

Inhibitors of Kelch-like ECH-associated protein 1 (Keap1) increase the activity of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) by stalling its ubiquitination and degradation. This enhances the expression of genes encoding proteins involved in drug detoxification, redox homeostasis, and mitochondrial function. Nrf2 activation offers a potential therapeutic approach for conditions including Alzheimer’s and Parkinson’s diseases, vascular inflammation, and chronic obstructive airway disease. Non-electrophilic Keap1-Nrf2 protein–protein interaction (PPI) inhibitors may have improved toxicity profiles and different pharmacological properties to cysteine-reactive electrophilic inhibitors. Here, we describe and characterize a series of phenyl bis-sulfonamide PPI inhibitors that bind to Keap1 at submicromolar concentrations. Structural studies reveal that the compounds bind to Keap1 in a distinct “peptidomimetic” conformation that resembles the Keap1-Nrf2 ETGE peptide complex. This is different to other small molecule Keap1-Nrf2 PPI inhibitors, including bicyclic aryl bis-sulfonamides, offering a starting point for new design approaches to Keap1 inhibitors

Phenyl Bis-Sulfonamide Keap1-Nrf2 Protein-Protein Interaction Inhibitors with an Alternative Binding Mode

[Image: see text] Inhibitors of Kelch-like ECH-associated protein 1 (Keap1) increase the activity of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) by stalling its ubiquitination and degradation. This enhances the expression of genes encoding proteins involved in drug detoxification, redox homeostasis, and mitochondrial function. Nrf2 activation offers a potential therapeutic approach for conditions including Alzheimer’s and Parkinson’s diseases, vascular inflammation, and chronic obstructive airway disease. Non-electrophilic Keap1-Nrf2 protein–protein interaction (PPI) inhibitors may have improved toxicity profiles and different pharmacological properties to cysteine-reactive electrophilic inhibitors. Here, we describe and characterize a series of phenyl bis-sulfonamide PPI inhibitors that bind to Keap1 at submicromolar concentrations. Structural studies reveal that the compounds bind to Keap1 in a distinct “peptidomimetic” conformation that resembles the Keap1-Nrf2 ETGE peptide complex. This is different to other small molecule Keap1-Nrf2 PPI inhibitors, including bicyclic aryl bis-sulfonamides, offering a starting point for new design approaches to Keap1 inhibitors

Presenilin1 familial Alzheimer disease mutants inactivate EFNB1- and BDNF-dependent neuroprotection against excitotoxicity by affecting neuroprotective complexes of N-methyl-d-aspartate receptor

Excitotoxicity is thought to play key roles in brain neurodegeneration and stroke. Here we show that neuroprotection against excitotoxicity by trophic factors EFNB1 and brain-derived neurotrophic factor (called here factors) requires de novo formation of 'survival complexes' which are factor-stimulated complexes of N-methyl-d-aspartate receptor with factor receptor and presenilin 1. Absence of presenilin 1 reduces the formation of survival complexes and abolishes neuroprotection. EPH receptor B2- and N-methyl-d-aspartate receptor-derived peptides designed to disrupt formation of survival complexes also decrease the factor-stimulated neuroprotection. Strikingly, factor-dependent neuroprotection and levels of the de novo factor-stimulated survival complexes decrease dramatically in neurons expressing presenilin 1 familial Alzheimer disease mutants. Mouse neurons and brains expressing presenilin 1 familial Alzheimer disease mutants contain increased amounts of constitutive presenilin 1-N-methyl-d-aspartate receptor complexes unresponsive to factors. Interestingly, the stability of the familial Alzheimer disease presenilin 1-N-methyl-d-aspartate receptor complexes differs from that of wild type complexes and neurons of mutant-expressing brains are more vulnerable to cerebral ischaemia than neurons of wild type brains. Furthermore, N-methyl-d-aspartate receptor-mediated excitatory post-synaptic currents at CA1 synapses are altered by presenilin 1 familial Alzheimer disease mutants. Importantly, high levels of presenilin 1-N-methyl-d-aspartate receptor complexes are also found in post-mortem brains of Alzheimer disease patients expressing presenilin 1 familial Alzheimer disease mutants. Together, our data identify a novel presenilin 1-dependent neuroprotective mechanism against excitotoxicity and indicate a pathway by which presenilin 1 familial Alzheimer disease mutants decrease factor-depended neuroprotection against excitotoxicity and ischaemia in the absence of Alzheimer disease neuropathological hallmarks which may form downstream of neuronal damage. These findings have implications for the pathogenic effects of familial Alzheimer disease mutants and therapeutic strategies.This work was supported by National Institutes of Health grants 2RF1AG008200-29; 2R01-NS047229; P50AG05138; and by Grant AARF-17-531426 of the Alzheimer’s Association.Peer reviewe

The pharmacological regulation of cellular mitophagy

Small molecules are pharmacological tools of considerable value for dissecting complex biological processes and identifying potential therapeutic interventions. Recently, the cellular quality-control process of mitophagy has attracted considerable research interest; however, the limited availability of suitable chemical probes has restricted our understanding of the molecular mechanisms involved. Current approaches to initiate mitophagy include acute dissipation of the mitochondrial membrane potential (ΔΨm) by mitochondrial uncouplers (for example, FCCP/CCCP) and the use of antimycin A and oligomycin to impair respiration. Both approaches impair mitochondrial homeostasis and therefore limit the scope for dissection of subtle, bioenergy-related regulatory phenomena. Recently, novel mitophagy activators acting independently of the respiration collapse have been reported, offering new opportunities to understand the process and potential for therapeutic exploitation. We have summarized the current status of mitophagy modulators and analyzed the available chemical tools, commenting on their advantages, limitations and current applications

The RO(G) Cohomology of Equivariant Classifying Spaces

We compute the $RO(G)$-graded cohomology of various $G$-equivariant classifying spaces, where $G$ is a cyclic 2-group. We then relate these descriptions to ``genuine" $G$-equivariant characteristic class and power operations. Depending on the context, we take coefficients $R$ in the constant Green functors $Z, F_2$ or the rational Burnside Green functor $A_Q$. The classifying spaces we study are $B_GL$ for $L$ a compact connected Lie group such as $U(m),SO(m),Sp(m)$. For certain combinations of $G,L$ and $R$, we compute $\underline{H}_G^{\bigstar}(B_GL;\underline{R})$ as an $RO(G)$-graded Green functor algebra over the cohomology of a point $\underline{H}_G^{\bigstar}(*;\underline{R})$. We also develop a computer program to partially verify and automate these computations. The results in this dissertation first appeared in the author's preprints [3,4,5,6,7]

Νανοδιασπορές ως μέσα μεταφοράς βιοδραστικών ενώσεων. Εφαρμογές στην αντικαρκινική θεραπεία.

Η στοχευμένη μεταφορά χημειοθεραπευτικών παραγόντων, ώστε να αποφευχθούν οι παρενέργειες και να ενισχυθεί η χημειοευαισθησία, παραμένει μείζον ζήτημα στην έρευνα για τη θεραπεία του καρκίνου. Σε αυτό το πλαίσιο, αξιολογήθηκε ένα βιοσυμβατό σύστημα μικρογαλακτώματος ελαίου-σε-νερό (O/W) ως φορέας ενθυλάκωσης λιπόφιλων βιοδραστικών μορίων. Ένα τέτοιο μόριο είναι η DPS-2, μία καινοφανής βιοενεργή χημική ένωση, η οποία εμφανίζει υψηλή κυτταροστατικότητα σε διάφορες ανθρώπινες κυτταρικές σειρές, ανάμεσα στις οποίες η WM 164 (δερματικό μελάνωμα) και η Caco-2 (αδενοκαρκίνωμα παχέος εντέρου). Το σύστημα μεταφοράς, αποτελούμενο από 81,5% w/w PBS, 10,6% w/w Tween 80 και 7,9% w/w τριακετίνη και όντας χαρακτηρισμένο δομικά με Δυναμική Σκέδαση Φωτός (DLS), Κρυογενική Ηλεκτρονική Μικροσκοπία (cryo-TEM) και Ηλεκτρονικό Παραμαγνητικό Συντονισμό (EPR), μελετήθηκε ως προς την ικανότητά του για ενδοκυτταρική απελευθέρωση λιπόφιλων ενώσεων με Συνεστιακή Μικροσκοπία. Επιπλέον, η κυτταροτοξική δράση του μικρογαλακτώματος O/W, παρουσία και απουσία της DPS-2, στις παραπάνω κυτταρικές σειρές, εξετάστηκε με δοκιμή βιωσιμότητας (ΜΤΤ). Το μικρογαλάκτωμα O/W, ως νανοφορέας, δεν είχε τοξική επίδραση και δεν παρουσίασε γονοτοξικότητα, όπως επιβεβαιώθηκε με δοκιμή Comet. Αντίθετα, η DPS-2, όταν χορηγήθηκε ενθυλακωμένη στο μικρογαλάκτωμα, αν και επίσης μη άμεσα γονοτοξική, εμφάνισε σημαντική κυτταροστατικότητα και στις δύο καρκινικές κυτταρικές σειρές, αλλά όχι σε κυτταρικές σειρές με λειτουργική πρωτεΐνη p53 (HLF-1 και Α549). Η εις βάθος κατανόηση, για το πώς μία δεδομένη χημικοθεραπευτική αγωγή επηρεάζει τα κυτταρικά σηματοδοτικά μονοπάτια που εμπλέκονται στον κυτταρικό θάνατο είναι επιβεβλημένη για την ανάπτυξη αποτελεσματικής αντικαρκινικής θεραπείας. Συνεπώς, διερευνάται ο μοριακός μηχανισμός του επαγόμενου κυτταρικού θανάτου, με τα μέχρι στιγμής πειραματικά ευρήματα να υποδεικνύουν πως η DPS-2 είναι αναστολέας του αναδιπλασιασμού του DNA, επάγωντας τελικά μη-αποπτωτικό κυτταρικό θάνατο μέσω επιβράδυνσης της φάσης S του κυτταρικού κύκλου. Σε εξέλιξη βρίσκεται η προσπάθεια για την αποσαφήνιση του μοριακού μηχανισμού του κυτταρικού θανάτου που επάγεται, καθώς και την ταυτοποίηση των σηματοδοτικών μονοπατιών που εμπλέκονται σε κάθε κυτταρικό τύπο.Targeted delivery of chemotherapeutics, in order to avoid side effects and enhance chemosensitivity, remains a major issue in cancer research worldwide. In this context, a biocompatible O/W microemulsion system was developed, as matrice for the encapsulation of lipophilic bioactive molecules. Such a molecule is DPS-2, a novel bioactive compound, exhibiting high cytotoxicity in various cancer cell lines, among them, the MW 164 skin melanoma and the Caco-2 human epithelial colorectal adenocarcinoma. The delivery system, composed of 81.5% w/w PBS buffer, 10.6% w/w Tween 80 and 7.9% w/w triacetin, was structurally characterized by Dynamic Light Scattering (DLS), Cryogenic-transmission electron microscopy (Cryo-TEM) and Electron Paramagnetic Resonance (EPR) and its capacity for intracellular release of lipophilic compounds was evaluated via Confocal Microscopy. The cytotoxic effect of O/W microemulsions, in the presence and absence of DPS-2, in the above cell lines, was examined through the MTT cell proliferation assay. The O/W microemulsion, as nanocarrier, had neither effect on cell lines’ viability nor genotoxic effect, as confirmed by a Comet test. In contrast, DPS-2, when loaded in microemulsion, although not showing direct genotoxicity, exhibited significant cytostaticity in the two cancer cell lines, but not in cell lines with functional p53 (HLF-1 and A549). A deep understanding of how a given chemotherapy affects cell signaling pathways involved in cell death is highly relevant in order to develop more effective therapeutics. Therefore, the molecular mechanism of the induced cell death is being investigated. Experimental evidence so far indicate that DPS-2 is a DNA replication inhibitor inducing a non-apoptotic cell death, through cell cycle arrest in the S-phase. Currently, further characterization of the type of the cell death induced as well as identification of the molecular pathways involved in each cell type, are ongoing