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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.
261

Effects of Selected Natural Health Products on Drug Metabolism: Implications for Pharmacovigilance

Liu, Rui 10 March 2011 (has links)
Seventeen Cree anti-diabetic herbal medicines and eight Traditional Chinese Medicines have been examined for their potential to cause interactions with drugs, which is considered as a major reason for adverse drug effects. Specifically, the effect of these natural health products was examined on major Phase I drug metabolism enzymes including cytochrome P450, human carboxylesterase-1 and flavin-containing monooxygenases. Several of these natural health products have the potential to cause adverse drug effect through the inhibition of major drug metabolism enzymes. The results indicated that 7 Cree medicines plant extracts inhibited CYP3A4 activity, and 3 of them have been proven to cause potent mechanism-based inactivation of CYP3A4. Seven of eight Traditional Chinese Medicines have been identified as strong CYP3A4 inhibitors; the ethanol extract of Goji has identified as a potent inhibitor for CYP2C9 and 2C19. Goji juice showed universal inhibitory effects on most of the tested enzymes except flavin-containing monooxygenases 3.
262

Stress driven changes in the kinetics of bilayer embedded proteins: a membrane spandex and a voltage-gated sodium channel

Boucher, Pierre-Alexandre 27 May 2011 (has links)
Bilayer embedded proteins are affected by stress. This general affirmation is, in this thesis, embodied by two types of proteins: membrane spandex and voltage-gated sodium channels. In this work, we essentially explore, using methods from physics, the theoretical consequences of ideas drawn from experimental biology. Membrane spandex was postulated to exist and we study the theoretical implications and possible benefits for a cell to have such proteins embedded in its bilayer. There are no specific membrane spandex proteins, rather any protein with a transition involving a large enough area change between two non-conducting states could act as spandex. Bacterial cells have osmovalve channels which open at near-lytic tensions to protect themselves against rupture. Spandex expanding at tensions just below the osmovalves’ opening tension could relieve tension enough as to avoid costly accidental osmovalve opening due to transient bilayer tension excursions. Another possible role for spandex is a tension-damper: spandex could be used to maintain bilayer tension at a fixed level. This would be useful as many bilayer embedded channels are known to be modulated by tension. The Stress/shear experienced in traumatic brain injury cause an immediate (< 2 min) and irreversible TTX-sensitive rise in axonal calcium. In situ, this underlies an untreatable condition, diffuse axonal injury. TTX sensitivity indicates that leaky voltage-gated sodium (Nav) channels mediate the calcium increase. Wang et al. showed that the mammalian adult CNS Nav isoform, Nav1.6, expressed in Xenopus oocytes becomes “leaky” when subjected to bleb-inducing pipette aspiration. This “leaky” condition is caused by a hyperpolarized-shift (left-shift or towards lower potentials, typically 20 mV) of the kinetically coupled processes of activation and inactivation thus effectively degrading a well-confined window conductance into a TTX-sensitive Na leak. We propose experimental protocols to determine whether this left-shift is the result of an all-or-none or graded process and whether persistent Na currents are also left-shifted by trauma. We also use modeling to assess whether left-shifted Nav channel kinetics could lead to Na+ (and hence Ca2+ ) loading of axons and to study saltatory propagation after traumatizing a single node of Ranvier.
263

Δημιουργία ζώων μοντέλων για τη διερεύνηση του in vivo ρόλου της geminin : αδρανοποίηση του γονιδίου σε μύες με τη χρήση ολοδύναμων εμβρυονικών κυττάρων (knockout) και ιστοειδική υπερέκφραση σε διαγονιδιακούς μύες

Κοταντάκη, Πανωραία 16 June 2011 (has links)
Η ανάπτυξη του ανοσοποιητικού συστήματος ξεκινά από πολυδύναμα αρχέγονα αιμοποιητικά κύτταρα, τα οποία διαδοχικά δίνουν γένεση σε ενδιάμεσους πληθυσμούς προγονικών κυττάρων οι οποίοι σταδιακά χάνουν την ικανότητά τους για αυτοανανέωση και τελικά δίνουν γένεση στα πλήρως διαφοροποιημένα κύτταρα της μυελικής και λεμφικής σειράς. Η συγκεκριμένη διαδικασία στηρίζεται στο λεπτό συντονισμό της αυτοανανέωσης, αλλά και της διαφοροποίησης, απαιτεί δε την έκφραση διαφορετικών γονιδίων που σχετίζονται με τη ρύθμιση του κυτταρικού κύκλου, τη μεταγραφική ρύθμιση γονιδίων, αλλά και συμπλόκων αναδιοργάνωσης της δομής της χρωματίνης που εμπλέκονται στη διαφοροποίηση. Η geminin έχει προταθεί ότι ρυθμίζει την απόφαση ενός κυττάρου για πολλαπλασιασμό ή διαφοροποίηση. Αλληλεπιδρά με μεταγραφικούς παράγοντες, με σύμπλοκα αναδιάταξης της δομής της χρωματίνης, ρυθμίζοντας την έκφραση γονιδίων που ελέγχουν τη νευρωνική διαφοροποίηση. Παράλληλα, δρα σαν αναστολέας του κυτταρικού κύκλου, προσδενόμενη στο παράγοντα αδειοδότησης της αντιγραφής του DNA, CDT1. Στόχος μας ήταν να διερευνήσουμε τον in vivo ρόλο της Geminin στη διαφοροποίηση και τον πολλαπλασιασμό, στο ανοσοποιητικό σύστημα. Στα πλαίσια της διδακτορικής διατριβής, βασιζόμενοι στο σύστημα Cre-loxP, δημιουργήσαμε μύες που επιτρέπουν την υπό συνθήκη εξάλειψη (knockout) του γονιδίου της geminin, πλαισιώνοντας τα εξώνια 3 και 4 του γονιδίου της με θέσεις loxP. Η στόχευση του γονιδίου και η παρεμβολή των 3 loxP θέσεων πραγματοποιήθηκε σε pc3 εμβρυικά πολυδύναμα κύτταρα μυός, χρησιμοποιώντας κατάλληλο πλασμιδιακό knockout φορέα, που έφερε τη κασέτα επιλογής TKneo. Μετά από ένεση των ορθά ανασυνδυασμένων pc3 κλώνων σε βλαστοκύστεις, τη δημιουργία χιμαιρικών μυών που εκφράζουν την Cre ρεκομπινάση στη γαμετική σειρά, και την επακόλουθη διασταύρωσή τους με μύες αγρίου τύπου, δημιουργήθηκαν ετερόζυγοι μύες για το πλαισιωμένο με loxP θέσεις αλληλόμορφο της Geminin, που παράλληλα έφερε και τη κασέτα επιλογής TKneo («floxed-ΤΚneo»), το πλαισιωμένο με loxP θέσεις αλληλόμορφο της Geminin, που στερούνταν της κασέτας επιλογής TKneo (floxed), καθώς επίσης και το αλληλόμορφο που στερούνταν των εξωνίων 3 και 4 και είναι το πλήρες knockout (ΔGEM ΚΟ -null) αλληλόμορφο). Από διασταυρώσεις ετερόζυγων για το ΔGEM ΚΟ αλληλόμορφο της geminin, δεν προέκυψαν ομόζυγοι μύες για το ΔGEM ΚO αλληλόμορφο (-/-), τόσο μεταγεννητικά όσο και in utero. Η μειωμένη αντιπροσώπευση των ΔGEM+/- μυών σε συνδυασμό με την αύξηση των Thy1-/B220- κυττάρων σε σπλήνα και λεμφαδένες ενήλικων μυών, η σημαντική αύξηση των Thy1+ και ειδικότερα των CD8+ Τ κυττάρων, καθώς επίσης και η αισθητή μείωση των CD4+ Τ κυττάρων του σπλήνα σε ζώα ηλικίας 5 μηνών, προτείνει ένα είδος απλοανεπάρκειας των ετερόζυγων για Geminin μυών. Σε παραπλήσια αποτελέσματα οδηγηθήκαμε και μετά από την ανάλυση των GT KO για το γονίδιο της Geminin (GT) μυών με τη μεθοδολογία της παγίδευσης γονιδίων. Τα ετερόζυγα GT ζώα διασταυρώθηκαν με ετερόζυγα ζώα για το πλήρες ΚΟ του BRG1 (BRG) και με ετερόζυγα ζώα που υπερεκφράζουν μια επικρατούσα κατασταλτική μορφή του BAF57 (BAFΔΝ, BAF), προκειμένου να διαπιστωθεί εάν υπάρχει γενετική αλληλεπίδραση μεταξύ της Geminin και των μελών του συμπλέγματος αναδιοργάνωσης της δομής της χρωματίνης SWI/SNF, BRG1 και BAF57 που έχει δειχθεί ότι παίζουν σημαντικό ρόλο κατά την ανάπτυξη και διαφοροποίηση του ανοσοποιητικού συστήματος. Ιστοειδικά, χρησιμοποιώντας την floxedΤΚneo σειρά μυών σε συνδυασμό με την CD2-Cre, που επιτρέπει την εξάλειψη του γονιδίου από το στάδιο των DN κυττάρων του θύμου και μετά, είδαμε ότι η ανάπτυξη του θύμου δεν φαίνεται να επηρεάζεται κατά την απουσία της Geminin, ενώ αντίθετα ο ολικός αριθμός των σπληνοκυττάρων μειώνεται στα FlTKneo/KO;CD2 σε σχέση με τα WT. Μιτωγονική διέγερση με ConA εναιωρήματος σπληνοκυττάρων από FlTKneo/KO;CD2 και WT ζώα, έδειξε ότι τα FlTKneo/KO;CD2 Τ λεμφοκύτταρα αδυνατούν να διαιρεθούν. Τέλος, έγινε προσπάθεια για ιστοειδική υπερέκφραση στο ανοσοποιητικό σύστημα της ανθρώπινης Geminin συντηγμένης με τη πράσινη φθορίζουσα χρωστική (GFP). Το συγκεκριμένο σύστημα επιτρέπει την υψηλή έκφραση του διαγονιδίου κυρίως στα Τ κύτταρα. Ενώ προέκυψαν ιδρυτές για όλες τις πιο πάνω σειρές τόσο με χαμηλή όσο και με υψηλή ενσωμάτωση του διαγονιδίου, η έκφραση της GFP δεν κατέστη δυνατόν να ανιχνευθεί με FACS. Συνοψίζοντας, τα αποτελέσματά μας καταδεικνύουν ότι η Geminin είναι ιδιαίτερα σημαντική κατά τα αρχικά στάδια ανάπτυξης του εμβρύου μυός, ενώ ιστοειδικά στο ανοσοποιητικό σύστημα η πλήρης εξάλειψή της δεν έχει καμία επίπτωση στην ανάπτυξη του θύμου αδένα, ενώ αντίθετα στη σπλήνα εμφανίζονται μειωμένοι οι πληθυσμοί των ώριμων CD4 και CD8 Τ λεμφοκυττάρων. Τέλος, φαίνεται να συνεργάζεται με το σύμπλεγμα αναδιοργάνωσης της δομής της χρωματίνης SWI/SNF στη ρύθμιση των CD4 κυττάρων του θύμου αδένα και των CD8 του σπλήνα. / Immune system development initiates from a multipotent hematopoietic stem cell that consecutively generates intermediate progenitors that concomitantly lose their self-renewal ability and finally generate the fully differentiated cells of the myeloid and lymphoid lineage. The whole procedure is based on the fine tuning of the processes of both self-renewal and differentiation, and requires the expression of diverse genes that are implicated in the processes of cell cycle regulation, transcriptional regulation, and are constituents of chromatin remodeling complexes that operate during differentiation. Geminin has been proposed to control a cell’s decision to proliferate or differentiate. It interacts with transcription factors, with chromatin remodeling complexes, regulating neurospecific gene transcription. At the same time, Geminin acts as a cell cycle inhibitor through direct binding to the DNA licensing factor CDT1. Our goal was to investigate Geminin’s in vivo role in differentiation and cell cycle regulation in the immune system. In this thesis, using Cre-loxP system, we generated conditional knockout mice for Geminin’s gene, flanking exons 3 and 4 with loxP sites. Gene targeting and the insertion of the three loxP sites was performed in pc3 mouse embryonic stem cells, using a suitable knockout plasmid vector, which bared the TKneo cassette selection marker. Upon injection of the homologously recombined pc3 clones into blastocysts, the generation of chimeric mice that expressed Cre recombinase in their germ line, and their subsequent cross to wild type mice, we were able to generate heterozygote mice for the flanked by loxP sites allele of Geminin that also bared TKneo selection marker (“floxed-TKneo” allele), the flanked by loxP sites allele of Geminin that was deprived of the TKneo selection marker (the floxed allele) and the complete knockout allele of Geminin (ΔGEM KO (null) allele) that was deprived of exons 3 and 4. From ΔGEM+/- intercrosses we didn’t recover any homozygote knockout mice, both postnatally and in utero. The reduced number of the ΔGEM+/- obtained, in combination with the dramatic increase of Thy1-B220- cells from spleen and lymph nodes from ΔGEM+/- adult mice, the significant increase in Thy1+ and CD8+ from lymph nodes and the discernible decrease of spleenic CD4 T cells in ΔGEM+/- aged 5 months suggest that ΔGEM+/- mice are haploinsufficient. Similar results were obtained from the analysis of the GT knockout that we generated, using a gene trap mutagenesis approach. GT heterozygote mice were crossed with heterozygote mice for BRG1 Knockout (BRG mice) and with heterozygote mice that overexpressed a dominant negative form of BAF57 (BAFΔN, BAF mice), so as to investigate whether there is a genetic interaction between Geminin and the two members of the SWI/SNF chromatin remodeling complex that have significant roles during development and differentiation of the immune system. Upon conditional inactivation of Geminin’s gene in the immune system, using floxedTKneo and CD2-Cre mouse lines, that allowed the deletion of the gene from the DN stage and on, we were surprised to see that in the Geminin conditional knockout mice, thymic development was largely unaffected. On the contrary, spleenic cellularity from Geminin conditional knockout mice was fairly reduced, when compared to WT control littermates. Mitogenic stimulation with ConA of spleenic whole cell extract from Geminin conditional KO (FlTKneo/KO;CD2) and WT mice demonstrated that the mutant T cells were unable to divide. Finally, we tried to overexpress human Geminin tagged with Green Fluorescent Protein (GFP) specifically in the immune system. This particular system would ensure high expression of the transgene mainly in T cells. We obtained founders for all of the cloned constructs, both with low and high copy transgene integration, but we were unable to detect GFP expression by FACS analysis. Our results show that Geminin has a pivotal role during early mouse embryonic development, whereas tissue specific inactivation in the immune system leaves thymic development largely unaffected, whereas mature CD4 and CD8 T cells in the spleen are drastically reduced. Finally, Geminin seems to operate with SWI.SNF complex for the regulation of thymic CD4 and spleenic CD8.
264

Avaliações das atividades fotossensibilizadoras do azul de metileno, da cloro-alumínio ftalocianina e do nitrosilo de rutênio no fungo Cryptococcus neoformans / Estimate of the photosensitizing activities of the methylene blue, chloroaluminum phthalocyanine and nitrosyl ruthenium complex in the fungus Cryptococcus neoformans.

Gabriela Braga Rodrigues 29 August 2008 (has links)
O basidiomiceto Cryptococcus neoformans é um fungo saprófita, com ampla distribuição geográfica, que é normalmente isolado de solos que contêm excretas de pombos e detritos vegetais. Apesar de saprófita, o fungo pode infectar e causar doença em uma grande variedade de hospedeiros animais, como mamíferos, aves e insetos. O número de casos de micoses graves, causadas por C. neoformans e por outros gêneros de fungos, tem aumentado em todo o mundo, principalmente devido ao aumento do número de indivíduos imunocomprometidos. Adicionalmente, a emergência de novas espécies de patógenos e a seleção de linhagens tolerantes aos antifúngicos comumente utilizados fazem com que o desenvolvimento de novas estratégias para o controle de fungos seja extremamente desejável. A inativação fotodinâmica de fungos é um método novo e promissor, que pode ser utilizado tanto para o controle de micoses (em animais e em vegetais), como para a eliminação de fungos do ambiente. A fotoinativação de fungos é baseada no uso de fotossensibilizadores que se acumulam ou que são preferencialmente metabolizados pelas células do microrganismo-alvo. A seguir, o fotossensibilizador é exposto à luz visível, que, na presença de oxigênio, inicia processos fotoquímicos que produzem uma série de espécies reativas de oxigênio capazes de matar as células fúngicas sem provocar danos significativos nos tecidos do hospedeiro. Neste trabalho, foram avaliadas as eficácias do azul de metileno (MB) (em solução e em nanoemulsão), da cloro-alumínio ftalocianina (em nanoemulsão) e do complexo nitrosilo de rutênio (em solução) como fotossensibilizadores para a fotoinativação de células melanizadas e não melanizadas de C. neoformans. C. neoformans foi suscetível à fotoinativação pela cloro-alumínio ftalocianina, com uma inativação próxima de 100% quando foi utilizada uma combinação apropriada da concentração do fotossensibilizador e da dose de luz. A completa fotoinativação do fungo pela ftalocianina, em condições compatíveis com a terapia fotodinâmica, abre a perspectiva da utilização desse fotossensibilizador para o tratamento de micoses causadas por C. neoformans. A fotoinativação pelo MB foi apenas parcial e não ocorreu fotoinativação pelo nitrosilo de rutênio. Nenhum dos fotossensibilizadores matou o fungo na ausência da luz. Também foram feitos experimentos para se verificar a influência do tempo de crescimento e da melanização na tolerância de C. neoformans à fotoinativação pelo MB. Houve diferença significativa na tolerância entre diferentes linhagens de C. neoformans. Para a maioria dos tratamentos [linhagens e tempo de crescimento (4, 6 ou 8 dias)], não houve diferença significativa entre a tolerância de células melanizadas e não melanizadas. Também não foi observada diferença na tolerância entre células com idade de 4 a 8 dias. / The basidiomycete Cryptococcus neoformans is a saprophytic worldwide fungus which is normally isolated from soils contaminated with pigeon excreta and plant detritus. Despite a saprophytic existence, the fungus can infect and cause disease in a wide variety of animal hosts such as mammals, birds and insects. Serious infections caused by C. neoformans and by other genera of fungi have emerged all over the world, primarily due to the increased numbers of immunocompromised individuals. Additionally, the emergence of new species and antimycotic-resistant strains of pathogenic fungi makes the development of new fungus-control techniques highly desirable. Photodynamic inactivation of fungi is a new and promising method that can be used to control localized mycoses or kill fungi in the environment. The photodynamic inactivation of fungi is based on the use of a photosensitizer that accumulates in, or preferentially is metabolized by, cells of the target microorganism. The photosensitizer is then exposed to visible light in the presence of oxygen, and this starts photochemical processes that produce a series of reactive oxygen species (ROS) capable of killing the fungal cells without causing significant damage to host tissues. We report here the efficacy of methylene blue (MB) (in solution and in nanoemulsion), chloroaluminum phthalocyanine (in nanoemulsion) and nitrosyl ruthenium complex (in solution) as photosensitizers in photoinactivation of melanized and nonmelanized Cryptococcus neoformans yeast cells. C. neoformans were susceptible to photoinactivation by chloroaluminum phthalocyanine with inactivation close to 100% when the appropriate combination of photosensitizer concentration and light-exposure dose was used. Photoinactivation by MB was only partial and nitrosyl ruthenium complex was ineffective. In the dark, neither photosensitizers inactivated the fungus. Complementary experiments were performed to estimate the effect of the age of the cells and of melanization in the fungus tolerance to photoinactivation by MB. There was a significative difference in the tolerance among strains of C. neoformans. For most of the treatments (strains and time of growth) there was no difference between the tolerance of melanized and nonmelanized cells. There was no difference in the tolerance among 4 to 8-day cells either.
265

Implication de l'hippocampe ventral et des noyaux reuniens et rhomboïde du thalamus dans les processus cognitifs sous-tendant la mémoire spatiale chez le Rat / lnvolvement of the ventral hippocampus and reuniens and rhomboid thalamic nuclei in cognitive processes underlying spatial memory in rats

Loureiro, Michaël 30 November 2012 (has links)
Ce travail de thèse avait pour objectif d’étudier le rôle de l’hippocampe (HPC) ventral et des noyaux reuniens (Re) et rhomboïde (Rh) du thalamus dans les processus cognitifs qui sous-tendent la mémoire spatiale chez le Rat. Par l’utilisation d’approches complémentaires combinant l’imagerie cérébrale, la lésion excitotoxique, l’inactivation fonctionnelle réversible et des évaluations comportementales, nos résultats ont mis en évidence : (1) l’implication spécifique de l’HPC ventral uniquement dans le rappel d’informations spatiales ; (2) un rôle-clé des noyaux Re et Rh dans la persistance d’un souvenir spatial ; (3) l’implication des noyaux Re et Rh dans le labyrinthe du double-H, un nouveau test nécessitant d’une part, l’utilisation d’informations spatiales dépendant de l’intégrité de l’HPC dorsal, et d’autre part, une flexibilité comportementale, impliquant le cortex préfrontal médian. Ainsi, l’ensemble de ces résultats permet de proposer l’existence d’un circuit HPC-préfronto-thalamique impliqué dans divers aspects du traitement des informations spatiales. / The main objective of this thesis was to investigate the role of the ventral hippocampus (HPC) and the reuniens (Re) and rhomboid (Rh) thalamic nuclei in the cognitive processes underlying spatial memory in the Rat. If our results first confirmed, in the Morris water maze, the role of the dorsal HPC in the acquisition and retrieval of a spatial reference memory, we demonstrated the specific involvement of the ventral HPC only in the recall of spatial information. In addition, by using complementary approaches combining brain imaging, excitotoxic lesion and reversible functional inactivation, we were able to show for the first time a key role for the Re and Rh in the persistence of a spatial memory (25 days). Finally, the third set of experiments has highlighted the involvement of the Re and Rh in a mnemonic task performed in a new test, the double-H maze, which requires the use of spatial information depending on the integrity of the dorsal HPC, and a behavioral flexibility, involving the medial prefrontal cortex. Thus, taken together, these results suggest the involvement of a HPC-prefronto-thalamic network in various aspects of spatial information processing.
266

Avaliação antibacteriana in vitro de extratos etanólicos de açafrão-da-terra (Curcuma longa L.) frente a microorganismos transmissíveis por alimentos

Paim, Marcelo Pinto January 2010 (has links)
Através de Testes de Diluição em Sistema de Tubos Múltiplos determinou-se in vitro a Intensidade de Atividade de Inibição Bacteriana (IINIB/bacteriostasia) e a Intensidade de Atividade de Inativação Bacteriana (IINAB/bactericidia) de soluções contendo extratos etanólicos a 50% de diferentes acessos in natura de rizomas (alcoolaturas), bem como diferentes amostras comerciais de pó de rizomas (hidroalcoolaturas) de açafrão-da-terra (Curcuma longa L.), sobre inóculos bacterianos padrões de Staphylococcus aureus (ATCC 25923), Salmonella Enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433) e Escherichia coli (ATCC 11229). Os extratos hidroalcoólicos apresentaram baixa atividade de inibição/inativação entre as quatro bactérias testadas, enquanto que a forma de extração alcoólica sem reidratação (extrato bruto) apresentou atividade antibacteriana seletiva e significativamente mais intensa. Salmonella Enteritidis e Enterococcus faecalis foram às bactérias mais sensíveis, frente a ambos os extratos (hidroalcoólico e alcoólico), enquanto que Escherichia coli e Stahphylococcus aureus apresentaram a menor sensibilidade. Houve diferença positiva significativa para os extratos não reconstituídos (bruto) quando comparados aos reconstituídos. / Through Test Dilution System in Multiple Tubes were determined in vitro the intensity bacterial inhibition activity (IINIB/bacteriostasys) and the Intensity of bacterial inactivation activity (IINAB/bactericidie) solutions containing 50% ethanol extracts of different accessions fresh root (alcoholic preparations) as well as commercial samples of powdered root (hidroalcoolaturas) from ground-saffron (Curcuma longa L.). patterns of bacterial inocula of Staphylococcus aureus (ATCC 25923), Salmonella Enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433) and Escherichia coli (ATCC 11229). The hydroalcoholic extracts showed low activity inhibition/inactivation among the four tested bacteria, while the form of alcohol extraction without rehydration (crude extract) showed selective antibacterial activity and significantly more intense. Salmonella enteritidis and Enterococcus faecalis bacteria were more sensitive, compared to both extracts (hydroalcoholic and alcohol), while Escherichia coli and Staphylococcus aureus Stahphylococcus showed the least sensitivity. There was a significant positive difference to the extracts not rehydrated (raw) when compared to rehydrated.
267

Avaliação de manifestações clínicas e laboratoriais em heterozigotas para mucopolissacridose tipo II

Pinto, Louise Lapagesse de Camargo January 2009 (has links)
Introdução: A maioria das doenças lisossômicas são herdadas como traços recessivos, mas a mucopolissacaridose tipo II (MPS II) é de herança ligada ao cromossomo X. As doenças ligadas ao cromossomo X possuem um importante impacto para as famílias devido ao risco que as heterozigotas apresentam em ter um filho afetado. A maioria das heterozigotas para as doenças ligadas ao cromossomo X são clinicamente assintomáticas. Em relação à MPS II somente dez mulheres afetadas foram relatadas na literatura. Entretanto, nenhum estudo foi realizado para a avaliação da presença de sinais sutis da doença nessas heterozigotas. Objetivo: o objetivo principal desse estudo foi a identificação de sinais clínicos sutis e bioquímicos relacionados à MPS II nas heterozigotas para essa doença e adicionalmente estabelecer a associação desses achados com o padrão de inativação do cromossomo X. Métodos: esse foi um estudo observacional e transversal. Essas mulheres foram classificadas como heterozigotas e não heterozigotas baseadas na análise molecular do gene da iduronato sulfatase (IDS). Ambos grupos foram comparados com relação às seguintes variáveis: dados clínicos, achados do exame físico, cariótipo, padrão de inativação do cromossomo X (ensaio HUMARA), atividades da IDS em leucócitos e plasma, níveis de glicosaminoglicanos na urina, tomografia computadorizada de abdomen e coluna e ressonância magnetica de crânio. Resultados: Quarenta mulheres pertencentes a 24 famílias foram avaliadas. De acordo com a análise do DNA 22 foram classificadas em heterozigotas e 18 em não heterozigotas. Não foi encontrada nenhuma anormalidade no exame físico (n=40), cariótipo (n=31/40) ou na TC de coluna (n=31/40). A incidência de abortamento também não apresentou diferenças entre essas mulheres. Entretanto, a atividade da IDS em plasma (p<0,001) e em leucócitos (p<0,001) apresentaram níveis inferiores nas heterozigotas. A correção de Bonferroni foi aplicada e não foi encontrada nenhuma diferença entre os grupos dentre as variáveis analisadas. Também em relação ao padrão de inativação do cromossomo X não foi observada diferença esntre as heterozigotas e não heterozigotas. Conclusões: Esse é o primeiro estudo sistemático realizado em heterozigotas para MPS II. Não foi encontrada nenhuma evidência de manifestações clínicas sutis ou sinais radiológicos da doença MPS II nessas mulheres. Nossos achados sugerem que não existe relação entre a ausência dos sinais clínicos nessas mulheres e a ocorrência de um padrão favorável de desvio da inativação do cromossomo X. Esses dados sugerem que a MPS II apresenta uma baixa penetrância nas heterozigotas. / Introduction: Most lysosomal diseases are inherited as recessive traits, but muchopolysaccharidosis type II (MPS II) presents X-linked inheritance. The X-linked disorders have an important impact for families because the risk heterozygous present of having an affected child. Most heterozygotes for X-linked disorders are clinically asymptomatic. Regarding MPS II only ten affected females have been reported in the literature. However, none study has been taken in order to evaluate subtle signs of the disease in heterozygotes. Objective: The main objective of this study was to identify subtle clinical and biochemical signs of MPS II in heterozygotes for this disease, and to correlate the findings with the pattern of X chromosome inactivation presented by these women. Methods: This was an observational, transversal and controlled study. The women were classified as heterozygote or non-heterozygote based on molecular analysis of the iduronate sulfatase (IDS) gene. Both groups were compared between regarding clinical data, physical exam findings, karyotype, pattern of X inactivation (HUMARA assay), IDS activity in leukocytes and plasma, glycosaminoglicans levels in urine, computadorized tomography scans of abdomen and spine, and brain magnetic resonance imaging. Results: Forty women from 24 families were evaluated. According to DNA analysis, 22 women were classified as heterozygote and 18 as non-heterozygotes. We did not found any abnormality in physical examination (n=40), karyotype (n=31/40) or spine CT scans (n=31/40). The incidence of miscarriage also did not differ between these females. However, IDS activities in plasma (p<0.001) and in leukocyte (p<0.001) were lower in heterozygotes. Applying the Bonferroni’s correction, we did not find any difference between the groups regarding the variables analyzed. Also the pattern of X chromosome inactivation was not different between heterozygotes and non-heterozygotes. Conclusion: This is the first systematic study performed in heterozygotes for MPS II. We did not find any evidence of subtle clinical manifestations or radiological signs of MPS II disease in these females. Our findings suggest that there is no relation between the absence of clinical signs in these women and the occurrence of a favorable skewing pattern of X chromosome inactivation. This data suggests that MPS II is a disease which shows low penetrance in heterozygotes.
268

Qualidade e estabilidade das propriedades físico-químicas e biológicas relacionadas as características fitoquímicas em Ipomoea batatas na perspectiva de cadeias de produção e de agregação de valor a alimentos em sistemas agropastoris familiares

José, António Elísio January 2016 (has links)
Experimentos com vista à avaliação das propriedades físico-quimica, fitoquímicas e biológica, bem como a sua estabilidade, em raízes tuberosas maduras, caules e folhas jovens de duas cultivares, RBS Amélia e RBS Cuia, e dois acessos de Ipomoea batatas, um de polpa púrpura com manchas brancas (C) e outro de polpa púrpura (D), cultivados ecologicamente e em condições de sequeiro na Horta Comunitária de Lomba do Pinheiro (30º 06’ 46’’ S; 51º 06’ 34’’ O) no Município de Porto alegre, RS no período de 2013 a 2015 foram efetuados nos laboratórios de Higiene, Qualidade e Microbiologia de alimentos e de Química e Bromatologia do Instituto de Ciência e Tecnologia de Alimento (ICTA) da Universidade Federal do Rio Grande do Sul (UFRGS). A avaliação quantita-tiva das propriedades físico-químicas e fitoquímicas seguiu os métodos descritos no Manual das Normas Técnicas para Determinação das Propriedades Físico-químicas em alimentos do Instituto Adolfo Lutz. O teor de polifenóis totais foi determinado pelo método de Folin & Ciocalteu, o con-teúdo de antocianinas pelo método de pH diferencial, os flavonoides, taninos e vitamina C avalia-dos por métodos espectrofotométricos. A atividade biológica consistiu na determinação das pro-priedades antioxidantes dos materiais usando o método fotocolorimétrico in vitro, empregando o radical livre estável 2,2-difenil-1-picrilhidrazila (DPPH) e na avaliação da atividade antimicrobi-ana, expressa como intensidade de atividade de inibição bacteriana (IINIB) e intensidade de ativi-dade de inativação bacteriana (IINAB), usando sistema de tubos múltiplos frente a diferentes con-centrações de Salmonella Enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433), Es-cherichia coli (ATCC 11229) e Staphylococcus aureus (ATCC 25923). Foi igualmente analisada a estabilidade físico-química, fitoquímica e biológica das raízes tuberosas, caules e folhas estoca-dos a temperatura ambiente por períodos de 90, 180 e 270 dias, através da mensuração e avaliação das concentrações dos componentes físico-químicos, fitoquímicos e atividade biológica naqueles pontos de estocagem, Foram encontrados teores de proteínas variando de 10,5 a 26,3%, carboidra-tos totais oscilando de 15,7 a 61,1% com valores altos observados na cultiva RBS Amélia. Maiores teores de fenólicos totais e antocianinas foram observados em acessos de polpa púrpura com valo-res até 709,3 e 78,7mg/100g, respectivamente. Elevada atividade antioxidante foi também verifi-cada na maioria dos extratos testados que, igualmente, evidenciaram atividade antibacteriana frente a todos os inóculos testados ainda que a sua intensidade tenha sido diferente. Porém, nenhuma atividade antibacteriana foi verificada em extratos preparados com base no calor, quais sejam in-fusão e decocção. A estabilidade das propriedades de todos esses materiais foi presenciada embora algumas características tenham reduzido seus teores aos 270 dias de estocagem. O trabalho conclui que as raízes tuberosas, caules e folhas das cultivares RBS Amélia e RBS Cuia e dos acessos de batata-doce estudados se constituem em hortaliças vegetais com alto potencial físico-químico, fi-toquímico e biológico, a avaliar pelos altos teores de carboidratos totais, considerável concentração de proteínas, elevados valores de polifenóis totais e, ou antocianinas, principalmente nos acessos de polpa púrpura. Os mesmos materiais têm um indicativo de atividade antioxidante e de atividade antibacteriana seletiva frente a Salmonella Enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229) e Staphylococcus aureus (ATCC 25923). Figuram-se, portanto, como uma excelente fonte de proteína, carboidratos e de compostos fenólicos relativamente estável por período de 270 dias de estocagem a temperatura ambiente, tornando-se importante na segurança alimentar e nutricional, saúde e bem-estar social. / Experiments for the evaluation of the physic-chemical, phytochemical and biological properties, and their stability in mature tuber roots, young stems and leaves of two cultivars, RBS Amelia and RBS Cuia and of two accessions of Ipomoea batatas, one having purple fleshed tuber roots with white spots (C) and another purple fleshed tuber (D), grown ecologically in “ Horta Comunitária da Lomba do Pinheiro (30º 06' 46'' S, 51° 06' 34'' O), Porto alegre, RS from the period of 2013 to 2015 were perfomed in the Hygiene, Quality and Microbiology and Food Chemistry laboratories of the Institute of Science and food Technology (ICTA), Federal University of Rio Grande do Sul (UFRGS). The quantitative assessment of physicochemical and phytochemical properties followed the described methods in the Manual of Technical Standards for Determination of Physical and Chemical Properties, Institute Adolfo Lutz. The total polyphenol content was determined by the Folin & Ciocalteu method, the content of anthocyanins at pH differential method, flavonoids, tan-nins, and vitamin C evaluated by spectrophotometric methods. Biological activity was analysed evaluated by determinating antioxidant properties of materials using fotocolorimétrico in vitro method, using the stable free radical 2,2-diphenyl-1-picrilhidrazila (DPPH) and also by evaluating antimicrobial activity, expressed as intensity of bacterial inhibition activity (IINIB) and intensity of bacterial inactivation activity (IINAB) using multiple tube system against different concentra-tions of Salmonella enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229) and Staphylococcus aureus (ATCC 25923). It was also analyzed the physical and chemical, phytochemical and biological stability of tuber roots, stems and leaves stored at room temperature for periods of 90, 180 and 270 days, through the measurement and assessment of con-centrations of physico-chemical components, phytochemicals and biological activity on those points of storage. Protein levels were found ranging from 10.5 to 26.3%, total carbohydrates rang-ing from 15.7 to 61.1% with higher values observed in the RBS Amelia cultivar. Higher total phe-nolic content and anthocyanins were found in the purple fleshed roos, with values of up to 709.3 and 78,7mg / 100g, respectively. High anti-oxidant activity was also observed in most of the tested extracts which also showed antibacterial activity against all inocula tested, although its intensity was different. However, no antibacterial activity was detected in extracts prepared by heat, namely infusion and decoction. The stability of the properties of all materials was attended although some features have reduced its contents to 270 days of storage. The paper concludes that the tuber roots, stems and leaves of the RBS Amélia and RBS Cuia cultivars and sweet potato accessions studied constitute vegetables with high physical-chemical, phytochemical and biological potential, accord-ing to the high levels of total carbohidrates, considerable protein concentration, high total polyphe-nol values, or anthocyanins, mainly in pupuple fleshed roots accesses. The same materials have an indicative of antioxidant activity and selective antibacterial activity against Salmonella enteritidis (ATCC 11076), Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229) and Sta-Staphylococcus aureus (ATCC 25923). Therefore, this specie can be seen as an excellent source of protein, carbohydrates and relatively stable phenolic compounds for a period of 270 days of storage at room temperature, making it important for food security and nutrition, health and social welfare.
269

Relação entre salmonelas isoladas de alimentos e extratos de plantas condimentares, na perspectiva de atividade antibacteriana e preditividade diagnóstica

Girolometto, Giovani January 2014 (has links)
As bactérias do gênero Salmonella são, atualmente, uma grande preocupação pela alta incidência de casos registrados, e um sério problema de saúde pública, pela severidade do processo infeccioso. Em função disto os protocolos de controle e legislações em vigilância em saúde obrigam a ausência total de Salmonella em alimento. Para garantir a segurança do alimento, uma crescente demanda de produtos naturais vem sendo estudas para controlar os patógenos alimentares. As plantas condimentares historicamente vêm sendo usadas para conferir sensorialidade aos alimentos, porém muitos desses recursos naturais possuem propriedades antimicrobianas. No entanto, pouco se sabe sobre a interação que essas especiarias influem sobre esses patógenos. Este estudo foi dividido em duas partes. Na primeira, através de testes de diluição em sistemas de tubos múltiplos, determinou-se a Intensidade de Atividade e Inibição Bacteriana (IINIB) e a Intensidade de Atividade e Inativação Bacteriana (IINAB) de diferentes extratos de Artemisia dracunculus L. (“estragão”) e Origanum vulgare L. (“orégano”) frente a oito isolados de Salmonella spp. de sete surtos toxinfectivos alimentares ocorridos no Rio Grande do Sul além de Salmonella Enteritidis ATCC (13076). Foram testados também diferentes formas de extração e suas concentrações, bem como o tempo de contato das bactérias ao extrato. A quantidade de polifenois totais foram, relacionadas à forma de extração (etanólica e hidroetanólico) e ao tipo de extrato da planta. Os resultados foram apresentados como variáveis arbitrárias sendo 9 a atividade máxima e 1 a não atividade bacteriana. Entre as Salmonella spp. houve diferença significativa (p >0,05) em IINIB 7,99 mais resistente a 8,28 mais sensível e os resultado em IINAB 6,77 mais resistente 7,22 mais sensível. As bactérias foram significativamente mais sensíveis aos extratos de estragão do que o de orégano da mesma forma a concentração de 25 % foi mais efetiva que as outras assim como o tempo de contato dos extratos com a bactéria resultou em maior atividade no tempo de 144h. Quanto ao tipo de extração a forma etanólica recebeu maiores notas que a extração Hidroetanólica e quando relacionada a quantidade de fenóis totais foram mais elevadas na etanólica e a planta com maior quantidade de polifenois foi o estragão. Com esses dados pode se dizer que as duas plantas mostraram ação bactericida e bacteriostática frente às salmonelas. Na segunda parte do trabalho contaminou-se carne bovina moída com inóculo padrão final em 104 UFC/mL de salmonela em contato com extratos de Artemisia dracunculus à concentração de 40 % e 45%, o extrato etanólico de Origanum vulgare L. Foi testada a sensibilidade do teste diagnostico de identificação de salmonelas criando uma modificação à técnica padrão oficial do Ministério da Agricultura, Pecuária e Abastecimento (MAPA) acrescentando desestressores que serviram de comparação (teste ouro). Para extrato de estragão observou-se uma sensibilidade do teste em 8 horas de 73,3% e em 24horas de 40% em quanto para orégano a sensibilidade do teste em 8 horas foi de 93,3% e em 24 horas de 6,6 %. Dessa forma o objetivo desse estudo foi trazer à discussão a necessidade de avaliar os processos de ativação das salmonelas originadas de alimentos contaminados, possibilitando uma qualificação dos resultados preditivos do teste oficial. / The Salmonella genus bacteria are currently a major concern because of the high incidence of reported cases, and a serious public health problem, due to the severity of the infectious process. Because of that, the control protocols and laws on health surveillance require a total absence of Salmonella in food. To ensure food security, there is a growing demand for natural products able to control food pathogens. The condiment plants have been historically used to flavor food, but many of these natural resources have antimicrobial properties. However, little is known about the action of the spices on those pathogens. This study was divided in two parts: The first, through dilution tests in a multiple tube testing system, we determined the Intensity of Activity and Bacterial Inhibition (IINIB) and Intensity of Activity and Bacterial Inactivation (IINAB) of different extracts of Artemisia dracunculus L. ("tarragon") and Origanum vulgare L. ("oregano"), compared to eight isolated types of Salmonella spp. from seven alimentary toxinfection outbreaks in Rio Grande do Sul, as well as Salmonella Enteritidis ATCC (13076). Different forms of extraction and their concentrations, as well as the contact time of the bacteria to the extracts were tested. The amount of total polyphenols were related to the form of extraction (ethanolic and hydroethanolic) and the type of the plant extract. The results were presented as arbitrary variables, showing 9 to the maximum activity and 1 to non-bacterial activity. Among Salmonella spp., there was significant difference (p> 0.05) in IINIB, 7.99 the most resistant to 8.28 the most sensitive, and results in IINAB 6.77the most resistant and 7.22 the most sensitive. The bacteria were remarkably more sensitive to tarragon extracts than oregano extracts. Similarly, the 25% concentration was more effective than the others, as well as the contact time of the extracts with the bacteria resulted in a higher activity within 144 h time. Regarding to the type of extraction, the ethanolic form showed higher scores than the hydroethanolic, and when related to the total amount phenols, these were higher in ethanolic extraction, and the highest amount of polyphenols was found in tarragon. With these data we can say that the two plants showed bactericidal and bacteriostatic action on the Salmonella. These data show that the two studied plants showed bactericidal and bacteriostatic action on the Salmonella. The second part of the study consisted in contacting contaminated ground meat with final standard inoculum 104 CFU / ml of Salmonella with extracts of Artemisia dracunculus in 40% and 45% concentration, and ethanol extract of Origanum vulgare. The responsiveness of the diagnosing test for identification of Salmonella was tested, creating a technical amendment to the official standard of the Ministério da Agricultura, Pecuária e Abastecimento (MAPA), adding de-stressors used as a comparison (gold standard). The tarragon extract showed responsiveness to the test within 8 hours at 73.3% and 24 hours at 40%, while for oregano the test responsiveness was within 8 hours at 93.3% and 24 hours at 6.6%. Therefore, the aim of this study was to discuss the need of evaluating the activation processes of the Salmonella originated from contaminated food, enabling a predictive qualification of the official test results.
270

Avaliação de manifestações clínicas e laboratoriais em heterozigotas para mucopolissacridose tipo II

Pinto, Louise Lapagesse de Camargo January 2009 (has links)
Introdução: A maioria das doenças lisossômicas são herdadas como traços recessivos, mas a mucopolissacaridose tipo II (MPS II) é de herança ligada ao cromossomo X. As doenças ligadas ao cromossomo X possuem um importante impacto para as famílias devido ao risco que as heterozigotas apresentam em ter um filho afetado. A maioria das heterozigotas para as doenças ligadas ao cromossomo X são clinicamente assintomáticas. Em relação à MPS II somente dez mulheres afetadas foram relatadas na literatura. Entretanto, nenhum estudo foi realizado para a avaliação da presença de sinais sutis da doença nessas heterozigotas. Objetivo: o objetivo principal desse estudo foi a identificação de sinais clínicos sutis e bioquímicos relacionados à MPS II nas heterozigotas para essa doença e adicionalmente estabelecer a associação desses achados com o padrão de inativação do cromossomo X. Métodos: esse foi um estudo observacional e transversal. Essas mulheres foram classificadas como heterozigotas e não heterozigotas baseadas na análise molecular do gene da iduronato sulfatase (IDS). Ambos grupos foram comparados com relação às seguintes variáveis: dados clínicos, achados do exame físico, cariótipo, padrão de inativação do cromossomo X (ensaio HUMARA), atividades da IDS em leucócitos e plasma, níveis de glicosaminoglicanos na urina, tomografia computadorizada de abdomen e coluna e ressonância magnetica de crânio. Resultados: Quarenta mulheres pertencentes a 24 famílias foram avaliadas. De acordo com a análise do DNA 22 foram classificadas em heterozigotas e 18 em não heterozigotas. Não foi encontrada nenhuma anormalidade no exame físico (n=40), cariótipo (n=31/40) ou na TC de coluna (n=31/40). A incidência de abortamento também não apresentou diferenças entre essas mulheres. Entretanto, a atividade da IDS em plasma (p<0,001) e em leucócitos (p<0,001) apresentaram níveis inferiores nas heterozigotas. A correção de Bonferroni foi aplicada e não foi encontrada nenhuma diferença entre os grupos dentre as variáveis analisadas. Também em relação ao padrão de inativação do cromossomo X não foi observada diferença esntre as heterozigotas e não heterozigotas. Conclusões: Esse é o primeiro estudo sistemático realizado em heterozigotas para MPS II. Não foi encontrada nenhuma evidência de manifestações clínicas sutis ou sinais radiológicos da doença MPS II nessas mulheres. Nossos achados sugerem que não existe relação entre a ausência dos sinais clínicos nessas mulheres e a ocorrência de um padrão favorável de desvio da inativação do cromossomo X. Esses dados sugerem que a MPS II apresenta uma baixa penetrância nas heterozigotas. / Introduction: Most lysosomal diseases are inherited as recessive traits, but muchopolysaccharidosis type II (MPS II) presents X-linked inheritance. The X-linked disorders have an important impact for families because the risk heterozygous present of having an affected child. Most heterozygotes for X-linked disorders are clinically asymptomatic. Regarding MPS II only ten affected females have been reported in the literature. However, none study has been taken in order to evaluate subtle signs of the disease in heterozygotes. Objective: The main objective of this study was to identify subtle clinical and biochemical signs of MPS II in heterozygotes for this disease, and to correlate the findings with the pattern of X chromosome inactivation presented by these women. Methods: This was an observational, transversal and controlled study. The women were classified as heterozygote or non-heterozygote based on molecular analysis of the iduronate sulfatase (IDS) gene. Both groups were compared between regarding clinical data, physical exam findings, karyotype, pattern of X inactivation (HUMARA assay), IDS activity in leukocytes and plasma, glycosaminoglicans levels in urine, computadorized tomography scans of abdomen and spine, and brain magnetic resonance imaging. Results: Forty women from 24 families were evaluated. According to DNA analysis, 22 women were classified as heterozygote and 18 as non-heterozygotes. We did not found any abnormality in physical examination (n=40), karyotype (n=31/40) or spine CT scans (n=31/40). The incidence of miscarriage also did not differ between these females. However, IDS activities in plasma (p<0.001) and in leukocyte (p<0.001) were lower in heterozygotes. Applying the Bonferroni’s correction, we did not find any difference between the groups regarding the variables analyzed. Also the pattern of X chromosome inactivation was not different between heterozygotes and non-heterozygotes. Conclusion: This is the first systematic study performed in heterozygotes for MPS II. We did not find any evidence of subtle clinical manifestations or radiological signs of MPS II disease in these females. Our findings suggest that there is no relation between the absence of clinical signs in these women and the occurrence of a favorable skewing pattern of X chromosome inactivation. This data suggests that MPS II is a disease which shows low penetrance in heterozygotes.

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