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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

MACROPHAGE MIGRATION INHIBITORY FACTOR AND LIVER DISEASE: THE ROLE OF MIF IN ALCOHOL-INDUCED LIVER INJURY AND CARBON TETRACHLORIDE (CCI4)-INDUCED LIVER FIBROSIS

Barnes, Mark Aaron, Jr 11 June 2014 (has links)
No description available.
42

Estudo do Fator Inibitório da Migração de Macrófagos(MIF) em pacientes com carcinoma epidermoide da cavidade bucal / Study of Macrophage Migration Inhibitory Factor (MIF) in patients with oral squamous cell carcinoma

Souza, Mariana Barbosa de 15 April 2014 (has links)
INTRODUÇÃO. A proteína Fator Inibitório da Migração de Macrófagos (MIF) é frequentemente observada com expressão elevada em tecidos tumorais quando comparados aos tecidos equivalentes normais e estudos têm sugerido seu papel como marcador prognóstico de neoplasias malignas, incluindo carcinomas hepatocelular, de ovário, de esôfago e também de cabeça e pescoço. Adicionalmente, alguns de seus mecanismos de ação já demonstrados, como a indução da proliferação e migração celular permitem implicar essa expressão diferencial no desenvolvimento tumoral e, consequentemente, no prognóstico das neoplasias malignas. OBJETIVO. Esse estudo objetivou avaliar o papel diagnóstico e prognóstico da proteína MIF em carcinoma epidermóide da cavidade bucal. METODOLOGIA. O estudo foi composto por 50 pacientes com carcinoma epidermoide da cavidade bucal coletados prospectivamente e 57 casos retrospectivos admitidos nos Serviços de Cirurgia de Cabeça e Pescoço do Hospital Heliópolis e da Faculdade de Medicina da Fundação ABC. As análises foram feitas por meio de imunoistoquímica dos tecidos tumorais e margens epiteliais normais e de ELISA das amostras de soro e saliva, coletadas pré e pós-tratamento cirúrgico, dos pacientes participantes. Os resultados foram correlacionados aos achados clínicos e histopatológicos. RESULTADOS. A expressão da proteína MIF e seu receptor CD74 mostrou-se elevada em tecido tumoral quando comparado ao tecido epitelial livre de neoplasia (p < 0,0001). Associação entre a alta expressão da MIF no tumor e infiltração vascular linfática foi observada (p=0,005) e alta expressão da MIF no epitélio livre de tumor apresentou correlação marginalmente significativa com ocorrência de segundo tumor primário (p=0,072). A expressão positiva do receptor CD74 não apresentou associação com variáveis clínicas ou histopatológicas. A concentração sorológica da proteína MIF apresentou associação inversa com metástase linfonodal (p=0,018) e estádios patológicos avançados (p=0,040) e foi significativamente reduzida após a ressecção do tumor (p=0,001). A concentração da MIF na saliva não apresentou redução significativa após o tratamento cirúrgico, mas foi associada aos estágios pT3 e pT4 (p=0,001) e a estádios patológicos avançados (p=0,032). CONCLUSÕES. A redução significante da concentração da MIF observada no soro dos pacientes após a ressecção cirúrgica do tumor permite sugerir papel potencial dessa proteína como biomarcador para a detecção precoce de recorrência do carcinoma epidermoide da cavidade bucal. A expressão tecidual da proteína MIF e seu receptor CD74 apresentou papel controverso, mas a concentração salivar da proteína MIF parece relacionar-se a um possível papel pró-tumoral em carcinoma epidermoide da cavidade bucal / INTRODUCTION. The Macrophage Migration Inhibitory Factor (MIF) overexpression is frequently observed in tumor tissues compared to normal tissues and some previous studies have suggested its role as a prognostic marker of malignancies, including hepatocellular, ovarian, esophageal and also head and neck carcinoma. Additionally, some of its mechanisms of action, as migration and cell proliferation induction, have been demonstrated, which allow imply a differential expression in tumor progression and therefore in the prognosis of malignant neoplasms. OBJECTIVES. This study aimed to evaluate the role of MIF protein and its receptor CD74 in prognosis and diagnostic of oral squamous cell carcinoma. METHODS. The study consisted of 50 patients with oral squamous cell carcinoma prospectively collected and 57 patients retrospectively collected admitted at the Head and Neck Surgery Service from Heliópolis Hospital and ABC Medical School. The analysis were performed by Imunohistochemistry of tumor and normal tissues and by ELISA of serum and saliva samples collected pre and post-surgical treatment. Results were correlated to clinical and histopathological data. RESULTS. The expression of MIF protein and of its receptor CD74 was higher in OSCC than in normal epithelium (p < 0,0001). Association between overexpression of MIF in tumor tissue and lymphatic vessel invasion was observed (p=0,005) and higher concentration of MIF in normal epithelium showed correlation of marginal significance with second primary tumor occurrence (p=0,072). The positive expression of the receptor CD74 did not presented association with clinical or histopathological variables. Serum MIF concentration presented inverse association with lymph node metastasis (p=0,018) and advanced pathological stage (p=0,040) and it was significantly reduced after the surgery (p=0,001). The salivary MIF concentration was not significantly reduced after the surgery, but it was associated with pT3 and pT4 stages (p=0,001) and advanced pathological findings (p=0,032). CONCLUSIONS. The results showing significant reduction of MIF concentration in post-surgical serum of patients suggest its potential role as a biomarker to early detection of oral squamous cell carcinoma recurrence. The MIF and CD74 expression presented controversial role, but the salivary concentration of MIF seems to develop a possible pro-tumoral role
43

Μελέτη του ρυθμιστικού ρόλου του παράγοντα αναστολής της μετανάστευσης των μακροφάγων (MIF) στην επίδραση των κορτικοειδών στην παραγωγή μεταλλοπρωτεασών και των ενδογενών αναστολέων τους, κυτταροκινών και κολλαγόνου στο ρινικό πολύποδα / Study of the regulatory role of macrophage migration inhibitory factor (MIF) on the effect of corticosteroids on production of matrix metalloproteinases and their inhibitors (TIMPS), cytokines and collagen type-I in nasal polyps

Σταθάς, Θεόδωρος 09 July 2013 (has links)
Στην παρούσα διατριβή μελετήθηκε η έκφραση του παράγοντα αναστολής της μετανάστευσης των μακροφάγων (MIF) στον ιστό από ρινικό πολύποδα αλλά και στον φυσιολογικό ρινικό βλεννογόνο, καθώς και η ικανότητα αυτού να εξουδετερώνει την ανασταλτική δράση των γλυκοκορτικοειδών (ΓΚ) στην επαγόμενη από διάφορους αυξητικούς παράγοντες παραγωγή διαμεσολαβητών, όπως η IL-6 η MMP-1, η MMP-3 το κολλαγόνο τύπου-Ι και ο TIMP-1, που εμπλέκονται στη παθογένεια του ρινικού πολύποδα (ΡΠ). Ο MIF ανιχνεύθηκε στο μέσο καλλιέργειας όλων των ιστών και σε όλα τα εκχυλίσματα. Η έκφρασή του ήταν αυξημένη στον ρινικό πολύποδα σε σχέση με τον φυσιολογικό ρινικό βλεννογόνο. O TGF-β1 προκάλεσε δοσο- και χρονο-εξαρτώμενη αύξηση των επιπέδων της IL-6 του TIMP-1 και του κολλαγόνου τύπου-Ι, και παράλληλα ο TNF-α προκάλεσε δοσο- αλλά και χρονο-εξαρτώμενη διέγερση στην παραγωγή της IL-6 του TIMP-1 και των μεταλλοπρωτεασών MMP-1 και MMP-3. Η δεξαμεθαζόνη προκάλεσε στατιστικά σημαντική και δοσοεξαρτώμενη μείωση της επαγόμενης από τον TGF-β1 και TNF-α, παραγωγής της IL-6 του TIMP-1 του κολλαγόνου τύπου-Ι και των μεταλλοπρωτεασών MMP-1 και MMP-3. Διερευνώντας τον μηχανισμό μέσω του οποίου η δεξαμεθαζόνη ασκεί την κατασταλτική της δράση στην επαγόμενη τόσο από τον TGF-β1 όσο και από τον TNF-α, παραγωγή της IL-6, φάνηκε πως αυτή εκδηλώνεται κυρίως μέσω της επαγωγής αλλά και της προστασίας της ΜΚΡ-1 και κατά συνέπεια της καταστολής του μονοπατιού των ΜΑΡΚ και της ενεργοποίησης του ΑΡ-1, και λιγότερο μέσω της καταστολής της ενεργοποίησης του NF-κB. Ο ISO-1, ένας αναστολέας της δράσης του MIF, ενίσχυσε σημαντικά την κατασταλτική επίδραση της δεξαμεθαζόνης στα επίπεδα της IL-6 και του TIMP-1 στο μέσο καλλιέργειας ιστού από ΡΠ, ενώ αντίθετα προκάλεσε αναστροφή της κατασταλτικής δράσης της δεξαμεθαζόνης, η οποία ήταν στατιστικά σημαντική για την ΜΜΡ-1 όχι όμως και για την ΜΜΡ-3. Η ενίσχυση της κατασταλτικής δράσης της δεξαμεθαζόνης παρουσία του ISO-1, που κυμάνθηκε από 15.0% έως 20.5% θα πρέπει μάλλον να οφείλεται στην αναστολή του ενδογενούς MIF από τον ISO-1. Συμπερασματικά, η παρουσία του MIF στον ιστό του ρινικού πολύποδα, φαίνεται να εξασθενίζει το κατασταλτικό αποτέλεσμα της δεξαμεθαζόνης στην παραγωγή IL-6 και TIMP-1 από αυτόν τον ιστό, ενώ η ταυτόχρονη χρήση του αναστολέα του MIF, ISO-1 οδηγεί σε μια περαιτέρω ενίσχυση της κατασταλτικής δράσης της δεξαμεθαζόνης. Έτσι, είναι λογικό κατ΄αρχήν, να προταθεί πως η δημιουργία ενός φαρμακευτικού σχήματος που περιέχει κορτιζόλη και ένα αναστολέα του MIF, θα μπορούσε να είναι πιο αποτελεσματικό στην θεραπεία της ΡΠ. Απαιτούνται περαιτέρω πειράματα με συνδυασμό ΓΚ και αναστολέων του MIF για να μελετηθεί η επίδρασή τους στη παραγωγή και άλλων παραγόντων που εμπλέκονται στη παθογένεια της ΡΠ προκειμένου να εξαχθούν ασφαλέστερα συμπεράσματα. / In the present study we investigated the expression of macrophage migration inhibitory factor (MIF) in nasal polyp tissues and also in normal nasal mucosa. The ability of MIF to neutralize the inhibitory effect of glucocorticoids on various growth factors induced expression of IL-6, TIMP-1, collagen type-I and matrix metalloproteinases MMP-1 and MMP-3, involved in the pathogenesis of nasal polyps, was studied. MIF was detected in all polyp tissue extracts and tissue culture conditioned media and its expression was increased in nasal polyps compared with normal nasal mucosa. TGF-b1 caused a dose-and time-dependent increase in levels of IL-6 of TIMP-1 and collagen type-I, while the TNF-a induced a dose-and time-dependent stimulation in the production of IL-6 of TIMP-1 and metalloproteinases MMP-1 and MMP-3. Dexamethasone caused a statistically significant and dose-dependent reduction induced by TGF-b1 and TNF-a, production of IL-6 of TIMP-1 of collagen type-I and the metalloproteinases MMP-1 and MMP-3. Investigating the mechanism by which dexamethasone exercises the suppressive action on both induced by TGF-b1 and by TNF-a, production of IL-6, showed that this occurs mainly through the induction and protection of MKP-1 and hence the suppression of the MAPK pathway and activation of AP-1, and less through the suppression of the activation of NF-kB. The ISO-1, an inhibitor of the action of MIF, significantly enhanced the suppressive effect of dexamethasone on the levels of IL-6 and TIMP-1 in tissue culture medium from nasal polyps. In contrary, ISO-1 induced inversion of the suppresive action of dexamethasone, which was statistically significant for MMP-1 but not for MMP-3. Enhancing of the suppresive action of dexamethasone in the presence of ISO-1, which ranged from 15.0% to 20.5% would probably be due to inhibition of endogenous MIF by ISO-1. In conclusion, the presence of MIF in nasal polyp tissue, appears to attenuate the suppressor effect of dexamethasone on the production of IL-6 and TIMP-1by this tissue, while simultaneously using the inhibitor of MIF, ISO-1 leads to an enhancement of dexamethasone activity. Therefore, it is reasonable to propose that the creation of a pharmaceutical regimen containing cortisol and an inhibitor of MIF, might be more effective in the treatment of nasal polyposis. Of course, requires further experiments with a combination of glucocorticoids and MIF inhibitors to study their effect on production of other factors involved in the pathogenesis of nasal polyposis in order to draw safer conclusions.
44

Estudo do Fator Inibitório da Migração de Macrófagos(MIF) em pacientes com carcinoma epidermoide da cavidade bucal / Study of Macrophage Migration Inhibitory Factor (MIF) in patients with oral squamous cell carcinoma

Mariana Barbosa de Souza 15 April 2014 (has links)
INTRODUÇÃO. A proteína Fator Inibitório da Migração de Macrófagos (MIF) é frequentemente observada com expressão elevada em tecidos tumorais quando comparados aos tecidos equivalentes normais e estudos têm sugerido seu papel como marcador prognóstico de neoplasias malignas, incluindo carcinomas hepatocelular, de ovário, de esôfago e também de cabeça e pescoço. Adicionalmente, alguns de seus mecanismos de ação já demonstrados, como a indução da proliferação e migração celular permitem implicar essa expressão diferencial no desenvolvimento tumoral e, consequentemente, no prognóstico das neoplasias malignas. OBJETIVO. Esse estudo objetivou avaliar o papel diagnóstico e prognóstico da proteína MIF em carcinoma epidermóide da cavidade bucal. METODOLOGIA. O estudo foi composto por 50 pacientes com carcinoma epidermoide da cavidade bucal coletados prospectivamente e 57 casos retrospectivos admitidos nos Serviços de Cirurgia de Cabeça e Pescoço do Hospital Heliópolis e da Faculdade de Medicina da Fundação ABC. As análises foram feitas por meio de imunoistoquímica dos tecidos tumorais e margens epiteliais normais e de ELISA das amostras de soro e saliva, coletadas pré e pós-tratamento cirúrgico, dos pacientes participantes. Os resultados foram correlacionados aos achados clínicos e histopatológicos. RESULTADOS. A expressão da proteína MIF e seu receptor CD74 mostrou-se elevada em tecido tumoral quando comparado ao tecido epitelial livre de neoplasia (p < 0,0001). Associação entre a alta expressão da MIF no tumor e infiltração vascular linfática foi observada (p=0,005) e alta expressão da MIF no epitélio livre de tumor apresentou correlação marginalmente significativa com ocorrência de segundo tumor primário (p=0,072). A expressão positiva do receptor CD74 não apresentou associação com variáveis clínicas ou histopatológicas. A concentração sorológica da proteína MIF apresentou associação inversa com metástase linfonodal (p=0,018) e estádios patológicos avançados (p=0,040) e foi significativamente reduzida após a ressecção do tumor (p=0,001). A concentração da MIF na saliva não apresentou redução significativa após o tratamento cirúrgico, mas foi associada aos estágios pT3 e pT4 (p=0,001) e a estádios patológicos avançados (p=0,032). CONCLUSÕES. A redução significante da concentração da MIF observada no soro dos pacientes após a ressecção cirúrgica do tumor permite sugerir papel potencial dessa proteína como biomarcador para a detecção precoce de recorrência do carcinoma epidermoide da cavidade bucal. A expressão tecidual da proteína MIF e seu receptor CD74 apresentou papel controverso, mas a concentração salivar da proteína MIF parece relacionar-se a um possível papel pró-tumoral em carcinoma epidermoide da cavidade bucal / INTRODUCTION. The Macrophage Migration Inhibitory Factor (MIF) overexpression is frequently observed in tumor tissues compared to normal tissues and some previous studies have suggested its role as a prognostic marker of malignancies, including hepatocellular, ovarian, esophageal and also head and neck carcinoma. Additionally, some of its mechanisms of action, as migration and cell proliferation induction, have been demonstrated, which allow imply a differential expression in tumor progression and therefore in the prognosis of malignant neoplasms. OBJECTIVES. This study aimed to evaluate the role of MIF protein and its receptor CD74 in prognosis and diagnostic of oral squamous cell carcinoma. METHODS. The study consisted of 50 patients with oral squamous cell carcinoma prospectively collected and 57 patients retrospectively collected admitted at the Head and Neck Surgery Service from Heliópolis Hospital and ABC Medical School. The analysis were performed by Imunohistochemistry of tumor and normal tissues and by ELISA of serum and saliva samples collected pre and post-surgical treatment. Results were correlated to clinical and histopathological data. RESULTS. The expression of MIF protein and of its receptor CD74 was higher in OSCC than in normal epithelium (p < 0,0001). Association between overexpression of MIF in tumor tissue and lymphatic vessel invasion was observed (p=0,005) and higher concentration of MIF in normal epithelium showed correlation of marginal significance with second primary tumor occurrence (p=0,072). The positive expression of the receptor CD74 did not presented association with clinical or histopathological variables. Serum MIF concentration presented inverse association with lymph node metastasis (p=0,018) and advanced pathological stage (p=0,040) and it was significantly reduced after the surgery (p=0,001). The salivary MIF concentration was not significantly reduced after the surgery, but it was associated with pT3 and pT4 stages (p=0,001) and advanced pathological findings (p=0,032). CONCLUSIONS. The results showing significant reduction of MIF concentration in post-surgical serum of patients suggest its potential role as a biomarker to early detection of oral squamous cell carcinoma recurrence. The MIF and CD74 expression presented controversial role, but the salivary concentration of MIF seems to develop a possible pro-tumoral role
45

Επίδραση του TGF-β1και του MIF στην παραγωγή IL-6 από ινοβλάστες ρινικού πολύποδα και διερεύνηση της πιθανής συνέργειάς τους στην έκφρασή της

Γιάννου, Αναστάσιος 05 February 2015 (has links)
Ο ρινικός πολύποδας (ΡΠ) είναι μια χρόνια φλεγμονώδης νόσος του ρινικού βλεννογόνου, η οποία χαρακτηρίζεται από διήθηση φλεγμονωδών κυττάρων, όπως ηωσινόφιλα, λεμφοκύτταρα και πλασμοκύτταρα, τροποποιήσεις στη διαφοροποίηση του επιθηλίου και ανάπλαση ιστού, που περιλαμβάνει υπερπλασία της βασικής μεμβράνης, συσσώρευση εξωκυττάριου υλικού και οίδημα. Ο παράγοντας αναστολής της μετανάστευσης μακροφάγων (MIF) είναι μία μοναδική κυτταροκίνη με σημαντικό ρόλο στο σηπτικό σόκ και στις χρόνιες φλεγμονώδεις και αυτοάνοσες ασθένειες.Παράγεται από ενεργοποιημένα Τ-κύτταρα, μακροφάγα αλλά και από ποικιλία άλλων κυττάρων. Εκτός των άλλων, έχει βρεθεί ότι επάγει την έκφραση της IL-6 από διάφορα κύτταρα και ανταγωνίζεται την κατασταλτική επίδραση των γλυκοκορτικοειδών στην έκφρασή της. Απαντάται σε αυξημένα επίπεδα στο ρινικό πολύποδα. Ο αυξητικός παράγοντας μετασχηματισμού-β1 (TGF-β1) θεωρείται ένας αντιφλεγμονώδης παράγοντες, ο οποίος ανταγωνίζεται τη δράση της IL-1β και του TNF-α, στην έκφραση της ΜΜΡ-1 και ΜΜΡ-3. Διεγείρει επίσης την έκφραση του ΤΙΜΡ-1, του κολλαγόνου τύπου Ι και της IL-6 και λόγω των δράσεών του αυτών εμπλέκεται ισχυρά στις διαδικασίες ίνωσης. Απαντάται σε σημαντικά επίπεδα στο ρινικό πολύποδα. Η IL-6 είναι μία Th2 πολυλειτουργική κυτταροκίνη η οποία εμπλέκεται σε ποικίλες φλεγμονώδεις καταστάσεις. Διεγείρει την ανάπτυξη των ινοβλαστών, αυξάνει τη σύνθεση και εναπόθεση του κολλαγόνου και μειώνει την αποικοδόμησή του. Απαντάται σε αυξημένα επίπεδα στο ρινικό πολύποδα και θεωρείται σημαντικός παθαγενετικός παράγοντας μέσω της επαγωγής του σχηματισμού των πλασμοκυττάρων και της σύνθεσης συστατικών του στρώματος, και της προαγωγής της σύνθεσης και εναπόθεσης κολλαγόνου και της ανάπλασης ιστού. Σκοπός της παρούσης εργασίας είναι η μελέτη της συμβολής του MIF και του TGF-β1 στη παραγωγή της IL-6 από ινοβλάστες ρινικού πολύποδα, των σηματοδοτικών μονοπατιών που εμπλέκονται, και η διερεύνηση της πιθανής συνεργειακής δράσης τους στην έκφραση της κυτταροκίνης. Τόσο ο TGF-β1 (0,01-1 ng/ml) όσο και ο MIF (1-100 ng/ml) προκάλεσαν διέγερση της έκφραση της IL-6 σε ινοβλάστες ρινικού πολύποδα κατά δοσοεξαρτώμενο τρόπο, η οποία κατεστάλλει σημαντικά από αναστολέις των ΜΑΡ κινασών και της ΡΙ-3 κινάσης. Ο TGF-β1 (1 ng/ml) προκάλεσε επίσης χρονοεξαρτώμενη αύξηση στα επίπεδα της IL-6 γιά χρόνο επώασης μέχρι 2 ώρες, τα οποιά έμεινα σταθερά στη συνέχεια μέχρι τις 72 ώρες επώασης, επαγωγή της παραγωγής ενδοκυτταρικών ενεργών ειδών οξυγόνου (ROS) με μέγιστο σε δύο χρόνους επώασης 20 και 180 λεπτά, και ενεργοποίηση των ERK κινασών από 15-60 λεπτά επώασης, με μέγιστη ενεργοποίηση στα 30 λεπτά, και στη συνέχεια πτώση στα επίπεδα του μάρτυρα. Ενώ ο MIF σε συγκέντρωση 1-100 ng/ml προκάλεσε μικρή μείωση στην έκφραση της φωσφατάσης-1 των ΜΑΡΚ (ΜΚΡ-1), ο TGF-β1 αντίθετα, σε συγκέντρωση 1 ng/ml προκάλεσε αύξηση στην έκφραση της ΜΚΡ-1 σε δύο χρόνους επώασης 0,5 και 24 ώρες. Μετά από επώαση των ινοβλαστών ρινικού πολύποδα παρουσία TGF-β1 (1 ng/ml) και MIF (100 ng/ml) μαζί, δεν παρατηρήθηκε συνεργειακή επίδραση στην έκφραση της IL-6. Ενώ τόσο ο TGF-β1 όσο και ο MIF προκάλεσαν διέγερση στην έκφραση της IL-6 από ινοβλάστες πνεύμονα, δεν παρατηρήθηκε και πάλι συνεργειακή επίδρασή τους στην έκφραση της κυτταροκίνης αυτής. Συμπερασματικά, φαίνεται ότι ο MIF, ενώ ανταγωνίζεται την κατασταλτική επίδραση των γλυκοκορτικοειδών στην έκφραση της IL-6 μέσω της ρύθμισης των επιπέδων της ΜΚΡ-1, δεν έχει την ίδια επίδραση στην έκφραση της IL-6 από τον TGF-β1, μέσω ρύθμισης της έκφρασης της φωσφατάσης αυτής. Από την άλλη μεριά η επαγωγή της έκφρασης της ΜΚΡ-1 από τον TGF-β1 φαίνεται να μην επηρεάζει την παραγωγή της IL-6 για μικρούς χρόνους επώασης, μέχρι 2 ώρες, πιθανόν λόγω της ανασταλτικής επίδρασης των ROS, που επάγονται από τον TGF-β1, στη δράση της ΜΚΡ-1, ενώ την επηρεάζει για μεγάλους χρόνους επώασης , εξ ού και τα σταθερά επίπεδα της IL-6 μέχρι και 72 ώρες επώασης. / Nasal polyp (NP) is a chronic inflammatory condition of nasal mucosa, characterized by infiltration of inflammatory cells such as eosinophils, lymphocytes and plasma cells, alterations in epithelial differentiation and tissue reconstruction, involving hyperplasia of basal membrane, accumulation of extracellular material and edema. Macrophage migration inhibitory factor (MIF) is a unique cytokine, the role of which in chronic inflammatory and autoimmune diseases and septic shock pathogenesis is very important. MIF is produced by activated T-lymphocytes, macrophages and a plethora of other cells. MIF appears to antagonize the suppressive effect of glucocorticoids as well as induce the expression of IL-6 in multiple cells. High levels of MIF are detected in nasal polyps. Transforming growth factor- β1 (TGF-β1) is an anti-inflammatory factor antagonizing the positive effect of IL-1β and TNF-α on the expression of MMP-1 and MMP-3, TGF-β1 also stimulates the expression of TIMP-1, collagen type I and IL-6; because of these effects, TGF-β1 is involved in the process of fibrosis. TGF-β1 levels in nasal polyps are significantly elevated. IL-6 is a cytokine participating in Th2 response and consequently is involved in a subset of inflammatory reactions. IL-6 stimulates the growth of fibroblasts, increases the production and deposition of collagen and it decreases its degradation. IL-6 is found in nasal polyps at elevated levels and it is thought to be an important pathogenic factor acting mainly in tissue reconstruction, stimulation of plasma cell differentiation, production of stromal material, promotion of collagen synthesis and deposition. The purpose of this paper is to study the effect of MIF and TGF-β1 in IL-6 production by fibroblasts isolated from nasal polyps, dissect the signaling pathways involved, and investigate their synergistic effect on the production of IL-6. Both TGF-β1 (0, 01-1 ng/ml) and MIF (1-100 ng/ml) induced IL-6 expression in nasal polyp fibroblasts in a dose-dependent manner. This effect was significantly suppressed by inhibitors of MAP and PI-3 kinase pathways. TGF-β1 (1 ng/ml) also induced IL-6 expression within 2 hours of administration. Elevated IL-6 levels remained unchanged for 72h further. TGF-β1 also promoted the production of intracellular reactive oxygen species (ROS), which peaked in 20 and 180 minutes and the activation of ERK kinase, peaked in 30 minutes. While MIF, at a concentration of 1-100 ng/ml, caused a slight decrease in the expression of phospatase-1 of MAPK (MKP-1), TGF-β1, at a concentration of 1 ng/ml, increased the expression of MKP-1. No synergistic effect on IL-6 expression was detected after incubating nasal polyp and lung fibroblasts together with TGF-β1 (1 ng/ml) and MIF (100 ng/ml). In conclusion, while MIF antagonizes the suppressive effect of glucocorticoids on the expression of IL-6 by regulating the levels of MKP-1, it fails to antagonize the TGF-β1 inducing effect on IL-6 via MKP-1. The induction of MKP-1expression by TGF-β1 is not affecting the production of IL-6 after short incubation periods; this effect can be explained by the inhibitory effect of TGF-β1 induced ROS on MKP-1. After prolong incubation with TGF-β1 (up to 72 hours), IL-6 levels remain elevated.
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Možnosti a limity stanovení specifických markerů zánětu oka na základě analýzy slz / Determination of inflammatory markers of the eye based on the analysis of tears - potential and limits

Mandíková, Šárka January 2018 (has links)
In this study, we aimed to determine the levels of cytokines IL-1β, IL-4, IL-10, IFN-γ, MIF and VEGF in tears derived from healthy subjects. We tested cytokines as potential markers of inflammation for their potential use in clinical practice. Having reliable method for measuring cytokine levels in tears would enable an early diagnosis of eye diseases. In two phases, cytokines in tears of healthy individuals were analyzed using Bio-Plex Cytokine Assay (Bio-Rad). We assessed the suitability of methods for diagnostic purposes as well as the suitability of our selected cytokines. Statistically significant positive correlations of cytokines were confirmed: IL-10 with IFN-γ (r = 0,81), MIF with VEGF (r = 0,42 / r = 0,49), IL-1β with IL-10 (r = 0,52), IL-1β with IFN-γ (r = 0,55), IL-1β with VEGF (r = 0,38), IFN-γ with VEGF (r = 0,45) and IL-4 with VEGF (r = 0,48) in healthy subjects in tears. IL-4 (r = -0,37) and IFN-γ (r = -0,42) correlate negatively with age. In healthy individuals, there seem to be no differences with regard to gender, BMI, body fat, time of meal consumption prior to tear collection, eye strain when using a computer, dry eyes. Thus, studied cytokines are suitable for diagnostic purposes. Significant differences in concentrations of four (IL-1β, IL-10, IFN-γ a VEGF) of the five...
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Ecrits de droit financier : de certaines insuffisances de la régulation financière / Writings of financial law : some insufficiencies of financial regulation

Boucheta, Haroun 28 June 2017 (has links)
Les écrits de Monsieur Haroun BOUCHETA, rassemblés en vue de l’obtention du titre de Docteur en droit, portent sur le droit financier. Depuis 2005, en prenant appui sur ses expériences professionnelles, l’auteur publie régulièrement des articles à destination tant des praticiens que des universitaires. Les écrits rassemblés sont de deux ordres. Premièrement, l’auteur s’intéresse à l’encadrement juridique de certains acteurs des marchés financiers ainsi qu’à celui d’instruments financiers et techniques financières.Parmi les acteurs étudiés, les contreparties centrales tiennent une place importante. Les études de l’auteur portant sur ce thème permettent d’appréhender l’environnement juridique et réglementaire spécifique et de comprendre ses récentes évolutions aux niveaux européen et français. Quant aux instruments financiers et techniques financières ayant fait l’objet de publications, l’auteur s’est essentiellement concentré sur les dérivés et les matières premières. Deuxièmement, d’autres écrits sont plus transversaux, voire prospectifs, puisqu’ils ont trait à des réformes européennes incontournables en matière de réglementation financière. A côté du règlement EMIR, l’auteur a consacré plusieurs études approfondies sur la réforme de la directive concernant les marchés d’instruments financiers (MIF). Ces écrits de droit financier sont accompagnés d’une introduction générale. La première partie s’appuie sur quinze articles publiés et a vocation à mettre en exergue certaines des lacunes de la régulation financière post-crise. Dans la seconde partie, l’auteur s’interroge sur la physionomie actuelle des sources du droit financier et sur le processus d’élaboration des textes. / The writings of Mr. Haroun BOUCHETA, gathered for the title of Doctor of Laws, deal with financial law. Since 2005, drawing on his professional experience, the author regularly publishes articles for both practitioners and academics. The collected writings are of two kinds.First, the author is interested in the legal framework of certain players in the financial markets as well as those of financial instruments and financial techniques.Among the actors studied, central counterparties play an important role. The author's studies on this subject make it possible to understand the specific legal and regulatory environment and to understand its recent developments at European and French levels.As for financial instruments and financial techniques that have been the subject of publications, the author concentrated mainly on derivatives and commodities.Secondly, other writings are more cross-cutting and even forward-looking, as they relate to unavoidable European reforms in financial regulation. In addition to the EMIR regulation, the author devoted several in-depth studies on the reform of the Markets in Financial Instruments Directive (MiFID).These writings of financial law are accompanied by a general introduction. The first part is based on fifteen published articles from the author and is intended to highlight some of the shortcomings of post-crisis financial regulation. In the second part, the author examines the current physiognomy of the sources of financial law and the process of drafting the texts.
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Le risque de découverte des prix sur les marchés boursiers : aspects théoriques et empiriques / The equity market and its price discovery risk

Ligot, Stephanie 20 October 2017 (has links)
La thèse se concentre sur l’étude des impacts de la directive européenne concernant les Marchés d’Instruments Financiers (MIF) et de sa révision (MIF II et MiFIR) sur le processus de découverte des prix. Selon Schreiber et Schwartz (1986), celui-ci est défini comme l´incorporation de l´information nouvelle dans le prix des actifs et la recherche de l´équilibre par le marché. Cette directive clé a pour objectif d´augmenter la concurrence et l´efficience au niveau des marchés européens tout en assurant la protection des investisseurs, ceci via une augmentation de la transparence et une exigence de politique de meilleure exécution des ordres de la part des firmes d´investissement. Plus particulièrement, l´étude se focalise sur les actions françaises du CAC40 qui peuvent désormais être échangées en dehors du marché national réglementé, Euronext Paris. Les plateformes multilatérales de trading, les internalisateurs systématiques et les dark pools sont des alternatives qui ont été introduites par la directive. En l´absence de consolidation du marché européen dans son ensemble et en présence d’une fragmentation spatiale des ordres de bourse, le risque est que certaines places d´échanges reçoivent plus d´ordres d´achat et d´autres, plus d´ordres de vente. Certains pensent que la technologie devrait lier des marchés spatialement fragmentés. Cependant, si suffisamment de flux d´ordres est retiré du marché réglementé et transparent, ce dernier pourrait ne plus assurer la découverte des prix car les prix et les quantités d´équilibre n´auraient pas été découverts par le marché dans son ensemble. De plus, même en présence d´un marché consolidé au niveau spatial, une fragmentation temporelle peut subsister. Elle correspond à la fracturation du flux d’ordres dans le temps, rendant la rencontre des ordres d´achat et de vente plus compliquée. […] La thèse apporte tout d’abord un éclairage sur les enjeux et les implications de la directive sur l’efficience des marchés européens. Dans le premier chapitre, nous proposons un cadre d´évaluation de la directive. Une sélection des principaux travaux académiques est réalisée dans le domaine de la microstructure des marchés afin d´identifier les problématiques restant sans réponse et les enjeux pour sa révision en cours (MIF II). Ensuite, une revue de la littérature sur le processus de découverte des prix du marché est opérée par la mise en lumière des principaux travaux théoriques, méthodologiques et empiriques. Les deux principales fonctions d´un marché sont de fournir de la liquidité et de permettre la découverte des prix. Cependant, la fonction de découverte des prix a souvent été un objectif de régulation négligé par rapport aux objectifs de transparence et de concurrence. […] / The thesis focusses on the impacts of the European Markets in Financial Instruments Directive (MiFID) and its revisions (the MiFID II and the MiFIR) on the price discovery process. According to Schreiber and Schwartz (1986), the price discovery process is defined as the incorporation of new information into the prices of assets and the search for an equilibrium by the market participants. This key directive aims to increase competition and efficiency at the European level without neglecting investor protection by increasing transparency and by requiring a best execution policy for the execution of client orders from investment firms.The study specifically highlights the CAC40 stocks, which, with the implementation of the MiFID, can be exchanged outside the regulated domestic market (Euronext Paris). The directive has introduced Multilateral Trading Facilities (MTFs), Systematic Internalisers (SI) and Dark Pools as alternative trading venues.In absence of an overall consolidation of the European market and in presence of a spatial fragmentation of orders, there is a risk that some exchange places may receive more buy orders and others more sell orders. Technology should bind spatially fragmented markets; however, if enough of the order flow were removed from the regulated and transparent market, it would be unable to ensure the price discovery because the equilibrium prices and quantities would not befound by the overall market. In addition, even in the presence of a consolidated market at the spatial level, temporal fragmentation may still exist. […]The first chapter studies the challenges and the implications of the MiFID on the efficiency of the European financial markets. This research proposes a regulatory framework to assess the directive. A selection of the principal academic work in the microstructure research area has been carried out in order to identify the remaining unanswered issues and challenges for the current revision of the MIF. The second chapter proposes a literature review of the concept of price discovery by highlighting the principal theoretical, methodological and empirical academic research. The two main functions of a market are to provide liquidity and to allow price discovery. However, the price discovery function has often been a neglected regulatory objective in comparison to transparency and competition objectives. It is important to assess the impacts of fragmentation on the quality of the market after the implementation of the MiFID. The object of study is the price discovery accuracy in the post-crisis context of more high-frequency and algorithmic trading. At this level, the thesis first offers a quantification of the degree of spatial and temporal fragmentation of CAC40 shares in the post-MiFID context. This study shows an increase in fragmentation. Furthermore, the quality of the market is evaluated from a price discovery perspective through the study of an indicator developed by Ozenbas et al. (2002, 2011) called the normalised volatility ratio. The study confirms the existence of a price discovery risk at the opening of the market before and after the implementation of MiFID. The potential causes of price discovery accuracy have been studied using three types of variables that characterise each transaction. The number of ransactions and the proportion of high-frequency traders on the buy side for the first half-hour of the day are significant variables for price discovery accuracy. In the post-MiFID scenario, spatial fragmentation does not significantly affect the market quality of CAC40 shares. At this level, temporal fragmentation seems to be a greater determinant. […]
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Development of high-performance algorithms for a new generation of versatile molecular descriptors. The Pentacle software

Durán Alcaide, Ángel 04 March 2010 (has links)
The work of this thesis was focused on the development of high-performance algorithms for a new generation of molecular descriptors, with many advantages with respect to its predecessors, suitable for diverse applications in the field of drug design, as well as its implementation in commercial grade scientific software (Pentacle). As a first step, we developed a new algorithm (AMANDA) for discretizing molecular interaction fields which allows extracting from them the most interesting regions in an efficient way. This algorithm was incorporated into a new generation of alignmentindependent molecular descriptors, named GRIND-2. The computing speed and efficiency of the new algorithm allow the application of these descriptors in virtual screening. In addition, we developed a new alignment-independent encoding algorithm (CLACC) producing quantitative structure-activity relationship models which have better predictive ability and are easier to interpret than those obtained with other methods. / El trabajo que se presenta en esta tesis se ha centrado en el desarrollo de algoritmos de altas prestaciones para la obtención de una nueva generación de descriptores moleculares, con numerosas ventajas con respecto a sus predecesores, adecuados para diversas aplicaciones en el área del diseño de fármacos, y en su implementación en un programa científico de calidad comercial (Pentacle). Inicialmente se desarrolló un nuevo algoritmo de discretización de campos de interacción molecular (AMANDA) que permite extraer eficientemente las regiones de máximo interés. Este algoritmo fue incorporado en una nueva generación de descriptores moleculares independientes del alineamiento, denominados GRIND-2. La rapidez y eficiencia del nuevo algoritmo permitieron aplicar estos descriptores en cribados virtuales. Por último, se puso a punto un nuevo algoritmo de codificación independiente de alineamiento (CLACC) que permite obtener modelos cuantitativos de relación estructura-actividad con mejor capacidad predictiva y mucho más fáciles de interpretar que los obtenidos con otros métodos.
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Homology modeling and structural analysis of the antipsychotic drugs receptorome

López Muñoz, Laura 22 June 2010 (has links)
Classically it was assumed that the compounds with therapeutic effect exert their action interacting with a single receptor. Nowadays it is widely recognized that the pharmacological effect of most drugs is more complex and involves a set of receptors, some associated to their positive effects and some others to the side effects and toxicity. Antipsychotic drugs are an example of effective compounds characterized by a complex pharmacological profile binding to several receptors (mainly G protein-coupled-receptors, GPCR). In this work we will present a detailed study of known antipsychotic drugs and the receptors potentially involved in their binding profile, in order to understand the molecular mechanisms of the antipsychotic pharmacologic effects.The study started with obtaining homology models for all the receptors putatively involved in the antipsychotic drugs receptorome, suitable for building consistent drug-receptor complexes. These complexes were structurally analyzed and compared using multivariate statistical methods, which in turn allowed the identification of the relationship between the pharmacological properties of the antipsychotic drugs and the structural differences in the receptor targets. The results can be exploited for the design of safer and more effective antipsychotic drugs with an optimum binding profile. / Tradicionalmente se asumía que los fármacos terapéuticamente efectivos actuaban interaccionando con un único receptor. Actualmente está ampliamente reconocido que el efecto farmacológico de la mayoría de los fármacos es más complejo y abarca a un conjunto de receptores, algunos asociados a los efectos terapéuticos y otros a los secundarios y toxicidad. Los fármacos antipsicóticos son un ejemplo de compuestos eficaces que se caracterizan por unirse a varios receptores simultáneamente (principalmente a receptores unidos a proteína G, GPCR). El trabajo de la presente tesis se ha centrado en el estudio de los mecanismos moleculares que determinan el perfil de afinidad de unión por múltiples receptores de los fármacos antipsicóticos.En primer lugar se construyeron modelos de homología para todos los receptores potencialmente implicados en la actividad farmacológica de dichos fármacos, usando una metodología adecuada para construir complejos fármaco-receptor consistentes. La estructura de estos complejos fue analizada y se llevó a cabo una comparación mediante métodos estadísticos multivariantes, que permitió la identificación de asociaciones entre la actividad farmacológica de los fármacos antipsicóticos y diferencias estructurales de los receptores diana. Los resultados obtenidos tienen interés para ser explotados en el diseño de fármacos antipsicóticos con un perfil farmacológico óptimo, más seguros y eficaces.

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