A privação dos hormônios sexuais, natural ou induzida, contribui para o aparecimento de diversas desordens metabólicas e endócrinas. Esse estudo investigou se a suplementação em dose única com DHEA, esteróide mais abundante em humanos, melhora a sensibilidade à insulina, bem como sua secreção e ou tolerância à glicose em ratas castradas alimentadas com dieta hiperlipídica (OHL). A castração induziu a perda da proteção fisiológica das fêmeas contra o ganho de peso. O tratamento com DHEA não promoveu alterações sobre esse parâmetro, porém, corrigiu a elevação na concentração de insulina plasmática e o índice HOMA IR, além da constante de decaimento de glicose, kitt. Os animais castrados apresentaram aumento da área da ilhota. DHEA não alterou essa condição. No entanto, as ilhotas das ratas tratadas com DHEA apresentaram aumento do grau de fosforilação da proteína Akt e melhora da capacidade secretória estática de insulina. Esse estudo sugere o uso do DHEA como alternativa protetora sobre a sensibilidade a insulina em fêmeas desprovidas de ovários. / Natural and induced privation of sexual hormones contributes to the development of several metabolic and endocrine disorders. The present study evaluated if DHEA supplementation, the most abundant steroid in humans, would improve the insulin sensitivity and secretion as well as the glucose tolerance, in high fat diet fed ovariectomized rats (OHL). Ovariectomy (OVX) reduced the physiological female protection against the weight gain. Although no effect upon adipose depot-specific action of DHEA has been found, DHEA has corrected the blood insulin levels and HOMA IR. In addition, DHEA has improved peripheral insulin action by the glucose disappearance rate, kitt. The islets area was increased in all ovariectomized groups. Pancreatic islets from DHEA-treated rats showed an increased in the Akt serine phosphorylation status and restored glucose-stimulated insulin secretion. Our results suggest that DHEA can promote protective effects by increasing the insulin sensitivity in females castrated rats exposed to health risk factors.

Chan Oi Chi. / "May 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 259-310) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Wong, Miu Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 140-152). / Abstracts in English and Chinese. / DECLARATION --- p.i / ACKNOWLEDGEMENT --- p.ii / ABBREVIATIONS --- p.iii / ABSTRACT IN ENGLISH --- p.iv / ABSTRACT IN CHINESE --- p.vii / TABLE OF CONTENTS --- p.ix / LIST OF FIGURES --- p.xii / LIST OF TABLES --- p.xviii / Chapter CHAPTER I - --- INTRODUCTION / Chapter 1.1 --- Regulation of human airway surface liquid --- p.1 / Chapter 1.2 --- Sodium reabsorption and chloride secretion in airway epithelium --- p.3 / Chapter 1.3 --- Purinergic receptors --- p.7 / Chapter 1.4 --- P2Y receptors in epithelial cells --- p.11 / Chapter 1.5 --- Autocrine or paracrine regulation of ion transport in epithelial cells --- p.13 / Chapter 1.6 --- Signaling pathways underlying the regulation of ion transport by P2Y receptors stimulation --- p.16 / Chapter 1.7 --- The therapeutic potential of P2Y receptors in treating cystic fibrosis --- p.18 / Chapter 1.8 --- Particular interest on P2Y6 receptor as potential target for treatment of cystic fibrosis --- p.21 / Chapter 1.9 --- Properties of 16HBE14o- cell line --- p.23 / Chapter 1.10 --- Objectives of the present experiments --- p.25 / Chapter CHAPTER II - --- MATERIALS AND METHODS / Chapter 2.1 --- Solutions and Chemicals --- p.26 / Chapter 2.2 --- Cell culture --- p.28 / Chapter 2.3 --- Simultaneous measurement of short-circuit current (Isc) and intracellular calcium concentration ([Ca2+ ])i --- p.29 / Chapter 2.3.1 --- Preparation of 16HBE14o- cells for simultaneous measurement of Isc and [Ca2+]i --- p.29 / Chapter 2.3.2 --- Measurement of Isc and transepithelial resistance with Ussing chamber --- p.32 / Chapter 2.3.3 --- Simultaneous measurement of Isc and [Ca2+]i --- p.35 / Chapter 2.4 --- Measurement of protein kinase A activity --- p.38 / Chapter 2.5 --- Data analysis --- p.39 / Chapter CHAPTER III - --- RESULTS / Chapter 3.1 --- Apical and basolateral application of P2Y agonists induced Isc and [Ca2+］i responses in 16HBE14o- cells --- p.40 / Chapter 3.1.1 --- Effect of apical and basolateral application of ATP on Isc and [Ca2+̐]ư --- p.40 / Chapter 3.1.2 --- Effect of apical and basolateral application of UTP on Isc and [Ca2+̐]ư --- p.45 / Chapter 3.1.3 --- Effect of apical and basolateral application of UDP on Isc and [Ca2+̐]ư --- p.50 / Chapter 3.1.4 --- "Summary of the effects of apical and basolateral application of ATP, UTP and UDP on Isc and [Ca2+̐]ư" --- p.55 / Chapter 3.2 --- Ionic mechanisms underlying the effect of apical and basolateral UDP on 16HBE14o- cells --- p.56 / Chapter 3.2.1 --- Differential effect of apical and basolateral UDP on Isc --- p.56 / Chapter 3.2.2 --- Effect of various apical CI－ channel blockers on Isc response induced by apical and basolateral application of UDP --- p.59 / Chapter 3.2.3 --- Effect of various basolateral K+ channel blockers on Isc response induced by apical and basolateral application of UDP --- p.83 / Chapter 3.3 --- Involvement of other signaling molecules or pathways in regulation of the chloride secreting response evoked by apical and basolateral UDP --- p.108 / Chapter 3.3.1 --- Effect of apical and basolateral UDP on PKA activity --- p.109 / Chapter 3.3.2 --- Effect of PKC inhibitors on Isc response induced by apical and basolateral application of UDP --- p.111 / Chapter CHAPTER IV - --- DISCUSSION / Chapter 4.1 --- Simultaneous measurement of Isc and [Ca2+ ̐]ư upon apical and basolateral application of P2Y agonists in 16HBE14o- cells --- p.125 / Chapter 4.2 --- Ionic mechanism underlying the effect of apical and basolateral UDP on 16HBE14o- cells --- p.128 / Chapter 4.2.1 --- Possible ionic mechanism for chloride secretion mediated by apical P2Y6 receptors --- p.131 / Chapter 4.2.2 --- Possible ionic mechanism for chloride secretion mediated by basolateral P2Y6 receptors --- p.133 / Chapter 4.3 --- Involvement of other possible signaling molecules or pathway underlying the action of apical and basolateral UDP --- p.135 / Chapter 4.4 --- Summary --- p.138 / Chapter CHAPTER V - --- REFERENCES --- p.140 / Publications --- p.153

The thesis is focused on the unprecedented phenomenon namelysecretory activity in female De Brazza´s monkey (Cercopithecus neglectus). The work gives a comprehensive overview of the life of monkeys. There is also a comparison with other related species of monkeys that live in similar or even identical conditions. It analyzes the olfactory and visual communication, for which it may have color and density of the discharge in the anogenital section key role. It compares discolouring outlet discharge of individual female in the experimental part.

A privação dos hormônios sexuais, natural ou induzida, contribui para o aparecimento de diversas desordens metabólicas e endócrinas. Esse estudo investigou se a suplementação em dose única com DHEA, esteróide mais abundante em humanos, melhora a sensibilidade à insulina, bem como sua secreção e ou tolerância à glicose em ratas castradas alimentadas com dieta hiperlipídica (OHL). A castração induziu a perda da proteção fisiológica das fêmeas contra o ganho de peso. O tratamento com DHEA não promoveu alterações sobre esse parâmetro, porém, corrigiu a elevação na concentração de insulina plasmática e o índice HOMA IR, além da constante de decaimento de glicose, kitt. Os animais castrados apresentaram aumento da área da ilhota. DHEA não alterou essa condição. No entanto, as ilhotas das ratas tratadas com DHEA apresentaram aumento do grau de fosforilação da proteína Akt e melhora da capacidade secretória estática de insulina. Esse estudo sugere o uso do DHEA como alternativa protetora sobre a sensibilidade a insulina em fêmeas desprovidas de ovários. / Natural and induced privation of sexual hormones contributes to the development of several metabolic and endocrine disorders. The present study evaluated if DHEA supplementation, the most abundant steroid in humans, would improve the insulin sensitivity and secretion as well as the glucose tolerance, in high fat diet fed ovariectomized rats (OHL). Ovariectomy (OVX) reduced the physiological female protection against the weight gain. Although no effect upon adipose depot-specific action of DHEA has been found, DHEA has corrected the blood insulin levels and HOMA IR. In addition, DHEA has improved peripheral insulin action by the glucose disappearance rate, kitt. The islets area was increased in all ovariectomized groups. Pancreatic islets from DHEA-treated rats showed an increased in the Akt serine phosphorylation status and restored glucose-stimulated insulin secretion. Our results suggest that DHEA can promote protective effects by increasing the insulin sensitivity in females castrated rats exposed to health risk factors.

Thesis (PhD)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Diabetes Mellitus (DM) is synonymous with "B-cell failure". Ligation of the pancreatic duct distally to its confluence into the bile duct has been shown to induce endocrine tissue regeneration from a number of probable sources. The cells responsible for regeneration are supposed to possess either dormant pluripotent stem cell ability and/or the plasticity to undergo metaplasia to form new and surplus endocrine tissue able to replace pathologically and/or experimentally compromised pancreas. The sequence of events (cell lineage) during this process of neogenesis, has been the source of controversy for quite some time as various studies suggest that the cell lineage differs from in vivo and in vitro studies, according to experimental model and species of laboratory animal. The object of this study was to utilise an established experimental laboratory animal model to study islet morphological changes, neogenesis and or both in vivo. Further aims of the study were to determine the extent, sequence and magnitude of pancreatic duct ligation (PDL) induced endocrine neogenesis/morphogenesis in a laboratory rat model using occlusive pancreatic duct ligation. PDL's were performed on six groups of 25 normal adult Sprague-Dawley (SD) rats (300g+) according to the method of Hultquist and Jonsson (1965). Experimental animals were sacrificed at 12 hr intervals from day one post-PDL to day 10 and every 24 hrs thereafter to day 14 as described by Wang, Klëppel, Bouwens (1995). Animals received BrdU (a thymidine marker and cell proliferation indicator) 50mglkg intraperitoneally as described by Wang et al. (1995), one hour prior to removal of the pancreas after which it was fixed in Bouin's solution and histologically processed. Seven consecutive 3-6 urn thick serial sections were sequentially stained with H & E, insulin (I), glucagon (G), somatostatin (ST), pancreatic polypeptide (PP), neuropeptide tyrosine (NPY) and peptide tyrosine tyrosine (PYY). Immunolabeling was done according to the method of Guesdon, Temynck , Avrameas (1979). Double immunolabeling for BrdU and each pancreatic peptide was performed on the sections on days 3,5, 7, 9 and 11 as described by Wang et al (1994). Cellular transformation between one and 3Yz days was characterised by simultaneous total deletion and/or transdifferentiation of the acinar compartment and the appearance of immunoreactive cells for I (11.53 ±1.5%), G (1.85 ±0.8%), pp (1.50 ±0.09%), and ST (1.96 ±0.24%). Changes in the endocrine composition in existing islets, occurred along a pathway that saw PP- and ST-cells invading the islet core, islet mantle glucagon deletion and random appearance of all endocrine cell types within the inter-islet interstitium on day 3Yz. Days 4 to 6Yz saw further endocrine expansion while days 7 to 14 were distinguished by islet reconstitution and consolidation. NPY immunoreactivity appeared on day 4Y2 and persisted intermittently throughout while PVV first appeared on day 4 and disappeared after day 7Yz. The results suggest that PDL firstly induced the development of endocrine tissue distributed haphazardly throughout the space previously occupied by acinar parenchyma. Secondly, the appearance of insulin is preceded by the appearance of PP, glucagon and somatostatin by 24-hours. A still to be determined proportion of the ligation induced endocrine formation appeared to be associated with existing islets, resulting in a number of very large islets, some of which might have secretory access through the glomerularlike capillary network known to occupy the islet core. The remainder appeared to form separate "new" islets, which have a dubious access to the blood stream. In conclusion, if it is true that the pancreas can regenerate some of its endocrine tissue then it has potential clinical implication for the stabilising of diabetes mellitus. Ligated exocrine pancreatic tissue, devoid of its acinar component, has been shown to contain notable quantities of insulin positive cells. This presents intriguing possibilities as an alternative for donor tissue, usually obtained from rat foetuses, during foetal rat pancreas transplantation studies. Pancreas tissue harvested from duct ligated rats could replace the foetal tissue currently used in the treatment of experimental diabetes mellitus in laboratory animals in this laboratory. / AFRIKAANSE OPSOMMING: Diabetes Mellitus is sinoniem met B-sel disfunksie. Endokriene regenerasie kan segmenteel bewerkstellig word deur eksperimentele afbinding van die pankreasbuis distaal tot sy samesmelting met die gemene galbuis. 'n Verskeidenheid van selle word vermoedelik by hierdie proses betrek. Dormante stamselle besit die vermoë en/of plastisiteit om 'n aantal vorms van metaplasie te ondergaan om nuwe en/of oortollige endokriene weefsel te vorm wat patologiese en/of eksperimenteel gekompromiseerde weefsel vervang. Die selontwikkelings volgorde wat tydens hierdie proses plaasvind is al vir 'n geruime tyd die middelpunt van 'n meningsverskil. Sommige studies dui daarop dat die in vivo selontwikkelingsvolgorde verskil van in vitro, volgens eksperimentele model en tipe proefdier gebruik. Die doel van die studie was die gebruik van 'n bestaande eksperimentele laboratorium proefdier model om pankreas eiland morfologiese verandering en/ofneogenese of beide in vivo te evalueer. Die oogmerk van die studie was om die omvang en volgorde van veranderings in die endokriene kompartement (neogenese/morfogenese) te bepaal deur gebruik te maak van 'n pankreas buis afbindings (PBA) model wat totale afsnyding van die buis tot gevolg het. PBA's is uitgevoer op ses groepe van 25 volwasse normale Sprague-Dawley (SD) laboratorium rotte (±300g) soos beskryf deur Hultquist en Jonsson (1965). Proefdiere is elke 12 uur geoffer vanaf dag een post-PBA tot dag tien en elke 24 uur daarna tot dag 14 soos beskryf deur Wang, Bouwens, Kloppel (1995) na die toediening van 50 mg/kg 5-Bromo-2-deoksi-uridien intraperitoneaal ('n selprolifererings aanduider) soos beskryf deur Wang et al. (1995). Die pankreas is werwyder, in Bouin se oplossing gefikseer en histologies geprosesseer. Sewe openvolgende seriesnitte (3-6 urn) is alternatiewelik gekleur met H & E, en immunositochemies, soos beskryf deur Guesdon, Terugnek, Avrameas (1979), vir insulien (I), glukagon (G), somatostatien (ST), pankreatiesepolipeptied (PP), neuropeptied tirosien (NPY) en peptied tirosien-tirosien (PYY). BrdU dubbel-immuunkleuring is ingesluit op dae 3,5, 7, 9 en 11 soos beskryf deur Wang et al. (1994). Sellulêre transformasie tussen dae een en 3~ dae is gekenmerk deur gelyktydige en totale uitwissing en/ofmetaplasie van die asinêre kompartement en die verskyning van selle immunorektiefvir I(11.53 ±1.5%), G (1.85 ±0.8%), PP (1.50 ±0.09%), ST (1.96 ±0.24%). Metaplasie was verantwoordelik vir merkbare veranderings in bestaande endokriene weefsel langs In transformasie weg waar eiland insulien kemselle vervang is deur PP- en ST-selle, glukagon buitelaag uitwissing en die toevallige verskyning van alle endokriene seltipes in the inter-eiland interstitium teen dag 3Y2. Dae 4Y2deur 6~ is gekenmerk deur verdere endokrinetoename terwyl dag 7 deur 14 gekenmerk is deur eiland hersamestelling en konsolidering. NPY immunoreaktiwiteit was vanaf dag 4~, met afwisseling, te bespeur terwyl PVV slegs tussen dae 4 en 7 In verskyning gemaak het. . Die resultate suggereer eerstens, PBA induseer die ontwikkeling van oortollige endokriene weefsel op In lukrake wyse versprei deur die ruimte voorheen deur asinêre parenchiem beset. Tweedens, dat die verskyning van insulien deur dié van PP, glukagon en somatostatien met minstens 24-uur voorafgegaan is. Die verhouding, van nuutgevormde endokriene weefsel wat met bestaande eilande assosieer om In aantal baie groot eilande te vorm, moet nog vasgestel word. Sulke strukture mag moontlik afskeidings toegang hê tot die bloedstroom, deur die glomerulusagtige kapillêre netwerk, in die eilandkern teenwoordig terwyl die oorblywende nuutgevormde endokrine weefsel "nuwe" apparte eilande vorm wat wel of gladnie toegang tot die bloedstroom mag hê nie. As gevolgtrekking, indien dit waar is dat volwasse pankreas eilandweefsel wel regenerasie kan ondergaan, dan het dit kliniese implikasie vir die stabilisering van diabetes mellitus. Weefsel verkry uit PBA bevat geen asinêre weefsel nie maar wel merkbare hoeveelhede endokriene weefsel, veral insulin positief. Dit bied dan interessante alternatiewe as skenker weefsel by fetal rot pankreas oorplantings. PBA en/of die oorplanting van pankreasbuis afgebinde weefsel, na in vitro weefsel kultuur, bied moontlikhede vir die behandeling van diabetes mellitus.

Nas secreções glandulares de anfíbios, muitos dos compostos isolados apresentam ação antifúngica e/ou antibacteriana, cuja função é protegê-los contra infecções, uma vez que estes animais habitam ambientes inóspitos. Os peptídeos têm-se destacado dentre os compostos com atividade antimicrobiana isolados de venenos de diversos animais. Além disso, compostos de natureza não proteica presentes nestas secreções têm demonstrado ação antimicrobiana. O objetivo deste estudo foi, primeiramente, isolar e caracterizar, estruturalmente, compostos com atividade antifúngica relevante. Em um segundo momento, foi realizar um estudo comparativo, através de técnicas ômicas, dos compostos presentes nas secreções das glândulas mucosas e parotoides. Os ensaios antimicrobianos, in vitro, foram realizados com fungos, leveduras e bactérias. O material de baixa massa molecular da água de diálise das secreções das glândulas parotoides apresentou atividade antimicrobiana sobre, principalmente, os fungos filamentosos. Este mesmo material foi submetido a uma filtração em gel, resultando em 11 frações as quais foram testadas contra Microsporum canis no ensaio de diluição seriada. A fração 9 mostrou atividade antifúngica e foi submetida a uma cromatografia de fase reversa, resultando em 9 frações, as quais foram testados contra M. canis. Destas frações, as frações 1 e 9 demonstraram, respectivamente, atividade fungicida e fungistática contra M. canis. No segundo momento, as secreções de ambas as glândulas foram analisadas por nanocromatografia líquida de ultra eficiência acoplada a um espectrômetro de massas de alta resolução. Desta análise, foram obtidos 11.034 compostos, distribuídos entre as secreções de ambas as glândulas. Todos os íons obtidos foram fragmentados (MS/MS) e submetidos à análise no programa PEAKS 6. Foram obtidas 511 sequências de peptídeos e/ou sequências parciais de proteínas das secreções das glândulas mucosas, enquanto que para as secreções das glândulas parotoides foram obtidas 110 sequências. Nas secreções das glândulas mucosas, a maior parte das sequências de aminoácidos são de compostos com massas moleculares entre 1 e 3 kDa, o que corresponde a 82% das sequências obtidas. Já para as secreções das glândulas parotoides, a maioria das sequências de aminoácidos são correspondentes aos peptídeos/proteínas com massas moleculares entre 1 e 2 kDa, o que representa 55% do total de sequências obtidas para esta secreção. As sequências foram analisadas pelo BLAST e revelou que um peptídeo presente nas secreções das glândulas parotoides apresenta 66,7% de identidade com o peptídeo antimicrobiano conhecido como ponericin-G2. Entre as sequências encontradas para as secreções das glândulas mucosas, o destaque foi para o precursor do peptídeo brevinin-1, com identidade de 31,2%. Todas as frações obtidas da filtração em gel das secreções das glândulas mucosas e parotoides foram direcionadas à análise por espectrometria de massas MALDI-TOF, o que resultou em maiores informações sobre a natureza dos compostos presentes nestas frações. A fração 8 das secreções das glândulas mucosas foi fracionada por cromatografia de fase reversa, resultando em 7 frações denominadas Pep1-Pep7. O composto denominado Pep7 teve sua massa molecular (6,012 kDa) determinada através da espectrometria de ressonância ciclotrônica de íons por transformada de Fourier com ionização por electrospray. Os peptídeos Pep4, Pep6 e Pep7 foram sequenciados pelo método de degradação de Edman. Estes peptídeos mostraram identidades com peptídeos antimicrobianos das famílias das tigerinin, shepherin e microcin e brevinins, respectivamente. Este estudo demonstrou que há compostos com atividade antimicrobiana significativa nestas secreções, principalmente para fungos filamentosos. Além disso, foi o primeiro a fazer uma análise comparativa dos compostos presentes nas secreções das glândulas mucosas e parotoides de R. schneideri, destacando a presença de peptídeos antimicrobianos / In amphibian glandular secretions, many of the isolated compounds have antifungal and/or antibacterial action, whose function is to protect the animal against infections, since they usually inhabit inhospitable environments. Peptides have been highlighted among antimicrobial compounds isolated from several venomous animals. In addition, non-proteic compounds present in these secretions have demonstrated antimicrobial action. The aim of this study was to isolate and structurally characterize antifungal compounds from Rhinella schneideri parotoid and mucous secretions. Moreover, in this study it was also performed a comparative study of the composition of mucous and parotid gland secretion by omics techniques. The low molecular weight material from parotoid gland secretion showed antimicrobial activity against filamentous fungi and bacteria. The low molecular weight material that showed antimicrobial activity was subjected to gel filtration, resulting in 11 fractions that were tested against Microsporum canis in serial dilution assay. The fraction 9 showed antifungal activity and it was subjected to a reversed phase chromatography, resulting in 9 fractions, which were tested against M. canis. Among them, fraction 1 and 9 showed fungicidal and fungistatic activity against M. canis, respectively. Gland secretion and the respective low molecular weight material were subjected to gel filtration and, each obtained fraction was analyzed by SDSTricine- PAGE. Secretion of the both glands were also quantitatively analyzed by nano ultraperformance liquid chromatography hyphenated to a high-resolution mass spectrometer. It was obtained 6,460 compounds distributed among secretions of both glands. All obtained ions were fragmented (MS/MS) and analyzed by PEAKS 6 program. 511 sequences were obtained from mucous gland secretion, against 110 sequences from parotoid gland secretion. In mucous gland secretion, most of the amino acid sequences (82%) are compounds with molecular masses between 1 and 3 kDa, while for parotoid gland secretion, most of sequences (55%) correspond to peptides/proteins with molecular masses between 1 and 2 kDa. Sequences were analyzed by BLAST, reveling a peptide in parotoid gland secretion that presents 66.7% of identify with an antimicrobial peptide known as ponericin-G2. Among sequences found in mucous gland secretion, the highlight was to one presenting 31.2% of identify with brevinin-1 precursor. All fractions obtained from gel filtration of the mucous and parotoid gland secretions were analyzed by MALDI-TOF mass spectrometry, which resulted in more informations about the nature of the compounds present in these secretions. Fraction 8 from mucous gland secretion was fractionated by reversed phase chromatography on C18 column, resulting in seven fractions denominated Pep1-Pep7. Pep7 presented a molecular mass of 6.012 kDa when analyzed by Fourier transform ion cyclotron resonance mass spectrometry. In this analysis, six precursor ions were identified, but no sequence was obtained. Pep4, Pep6 and Pep7 were sequenced by Edman degradation method. These peptides showed identity with tigerinin, shepherin and microcin and brevinins, respectively. This study revealed compounds with significant antimicrobial activity in the analyzed secretions, especially to filamentous fungi. In addition, it was the first to perform a comparative analysis of compounds present in mucous and parotoid gland secretion from R. schneideri toad, highlighting the presence of antimicrobial peptides

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Title from first page of PDF file (viewed Feb 17, 2009). Includes bibliographical references.

Η βλέννα του σαλιγκαριού έχει χρησιμοποιηθεί στην ιατρική από την αρχαιότητα από την εποχή του Ιπποκράτη, ο οποίος είχε προτείνει τη χρήση της βλέννας για την καταπολέμηση του πόνου, εγκαυμάτων και άλλων τραυμάτων. Πρόσφατη επιστημονική μελέτες του εκκρίματος του σαλιγκαριού Helix aspersa επιβεβαίωσαν ότι η βλέννα περιέχει ένα ασυνήθιστο συνδυασμό φυσικών προϊόντων με ευεργετικές και θεραπευτικές ιδιότητες στο ανθρώπινο δέρμα. Η βλέννα του σαλιγκαριού παρουσιάζει σημαντικό οικονομικό - εμπορικό ενδιαφέρον, ως προς την αξιοποίηση των χημικών συστατικών της όπως η αλλαντοΐνη και το γλυκολικό οξύ που χρησιμοποιούνται ευρύτατα ως δραστικά συστατικά κατά την παρασκευή φαρμακευτικών και καλλυντικών προϊόντων. Η αλλαντοΐνη είναι μία ετεροκυκλική οργανική ένωση που παράγεται από την κατάλυση των πουρινών από το ένζυμο καταλάση. Παρουσιάζει μια μακρά ιστορία όσον αφορά στη χρήση της σε μια ποικιλία από τοπικά φάρμακα και καλλυντικά προϊόντα για την περιποίηση του δέρματος. Το γλυκολικό οξύ είναι το μικρότερο α-υδροξύ - οξύ (AHA). Χάρη στην εξαιρετική ικανότητά του να διαπερνάει το δέρμα, βρίσκει εφαρμογές σε διάφορα προϊόντα φροντίδας του δέρματος, για τη βελτίωση της εμφάνισης και της υφής του δέρματος μειώνοντας ρυτίδες, ουλές ακμής, υπέρχρωση και άλλα και σε άλλες δερματικές παθήσεις. Στην παρούσα εργασία έγινε προσπάθεια ανάπτυξης μεθοδολογιών για τον ποιοτικό και ποσοτικό προσδιορισμό της αλλαντοΐνης και του γλυκολικού οξέος. Με χρωματογραφία υψηλής απόδοσης (HPLC-DAD) σε στήλη Synergi RP (Phenomenex ®) επετεύχθη πολύ καλός διαχωρισμός εντός 6 min. Οι τελικές συνθήκες διαχωρισμού (ισοκρατική έκλουση με εκλούτη ρυθμιστικό διάλυμα 10 mM KH2PO4 pH 2.7 και η ροή ρυθμίστηκε στο 0.7 mL/min και στους 30 C) και προκατεργασίας δείγματος (αραίωση της βλέννας στο ρυθμιστικό διάλυμα, θέρμανση στους 60 C για 20 λεπτά και εκχύλιση με εξάνιο) επιλέχθηκαν μετά από μελέτη διαφόρων παραμέτρων που αφορούν στη σύσταση του εκχυλιστικού μέσου και της κινητής φάσης. Η μέθοδος επικυρώθηκε ως προς τα αναλυτικά της χαρακτηριστικά (γραμμικότητα, επαναληψιμότητα, ακρίβεια και σταθερότητα). Ανάλυση της βλέννας του σαλιγκαριού Helix aspersa έδειξε ότι περιέχει 48.610 ± 0.002, 47.590 ± 0.001, 52.820 ± 0.001 mg/L αλλαντοΐνης και 3753.01 ± 0.01, 3170.51 ± 0.02, 1979.23 ± 0.02 mg/L γλυκολικού οξέος για τις τρεις παρτίδες που αναλύσαμε, αντίστοιχα. Η προτεινόμενη μεθοδολογία χρησιμοποιήθηκε για την ποσοτική ανάλυση τριών καλλυντικών κρεμών (Elicina της εταιρίας Cosméticos Elicina Ltda, Santiago, Χιλή, Labcconte της εταιρίας Cosméticos Concepción Ltda, Χιλή και μια κρέμα από την εταιρία Helix ir στην Κρήτη) στις οποίες η βλέννα του σαλιγκαριού αναγράφεται να περιέχεται σε υψηλό ποσοστό (85%). Τα αποτελέσματα μας δείχνουν ότι τα καλλυντικά σκευάσματα περιέχουν 0.110 ± 0.003, 0.260 ± 0.010 , 0.370 ± 0.001 mg/L αλλαντοΐνης και 4.520 ± 0.010, 5.350 ± 0.010, 5.690 ± 0.001 mg/L γλυκολικού οξέος, αντίστοιχα. / The snail mucus has been used in medicine since the time of Hippocrates, who proposed the use of mucus to combat pain, burns and other wounds. Recent scientific studies of the snail secretion Helix Aspersa confirmed that the snail contains an unusual combination of natural products which are beneficial for human skin. The last time the mucus of the snail has important economic - commercial interest in the use of chemical components such as allantoin and glycolic acid are widely used as active ingredients in the manufacture of pharmaceutical and cosmetic products. Allantoin is a heterocyclic organic compound produced by the breakdown of purines by the enzyme catalase. It has a long history in the use of a variety of topical medications and cosmetics for skin care. The glycolic acid is the smallest alpha-hydroxy acid (AHA). Thanks to its excellent ability to penetrate the skin, it finds applications in various skin care products, for improving the appearance and texture of skin by reducing wrinkles, acne scars, hyperpigmentation and also can improve many other skin disorders. In this study we developed analytical methodology for qualitative and quantitative determination of allantoin and glycolic acid. Application of highperformance chromatography (HPLC-DAD) on a Synergi RP (Phenomenex ®) column has provided a very good separation within 6 min. The final separation (isocratic elution with buffer 10 mM KH2PO4 pH 2.7 as eluent and flow rate 0.7 mL/min at 30 °C) and sample pretreatment (by dilution the mucus in the buffer, heated at 60 °C for 20 min and extracted with hexane) were selected after a study of various parameters relating to the extraction medium and the mobile phase. The method was validated in terms of analytical characteristics (linearity, repeatability, accuracy and stability). Analysis of the snail secretions Helix aspersa showed that it contains 48.610 ± 0.002, 47.590 ± 0.001, 52.820 ± 0.001 mg/L allantoin and 3753.01 ± 0.01, 3170.51 ± 0.02, 1979.23 ± 0.02 mg/L glycolic acid for three batches that we analyzed, respectively. The methodology was used for quantitative analysis of three cosmetic creams (Elicina from the company: Cosméticos Elicina Ltda, Santiago, Chile, Labcconte from the comany: Cosméticos Concepción Ltda, Chile and a cream from the company: Helix ir in Crete) where the snail mucus is deemed to be about 85%. Our results show that cosmetic products contain 0.110 ± 0.003, 0.260 ± 0.010 , 0.370 ± 0.001 mg/L allantoin and 4.520 ± 0.010, 5.350 ± 0.010, 5.690 ± 0.001 mg/L glycolic acid, respectively.

Made available in DSpace on 2015-03-26T13:30:50Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1253123 bytes, checksum: 10d2730e30805f09a7de54191207b48f (MD5) Previous issue date: 2014-02-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The dung beetle, from the subfamily Scarabaeinae, use feces and carrion as a food source and for their breeding. The ephemeral nature of these resources creates a strong intra and interspecific competition between species that use them. The rolling of dung is a mechanism to relocate food and hence avoid competition. The main interspecific competitors of the roller beetles are flies, including those belonging to the Calliphoridae family. To prevent attack of their food by flies, the dung beetles can cover the ball with a layer of soil. However, this does not seem to be the only mecanism, since when scrolling the ball they may secrete substances that impregnate the ball and possibly act as chemical defense against these competitors. Thus, the present study investigated the effect of rolled food balls and pygidiales secretions produced by the copro-necrophagous beetle Deltochilum furcatum on oviposition of Lucilia cuprina, a fly with high preference to oviposite in carrion. The results showed that, when the food ball is rolled, females and males of D. furcatum impregnate substances to the ball of food that significantly affects L. cuprina oviposition. The male pygidial secretion presented a greater dissuasive effect on L. cuprina compared to the female pygidial secretion. It is possible that the pygidial secretion acts together with other secretions produced by D. furcatum as allomones in the oviposition of L. cuprina and other potential competitors. In situations where there is no possibilities of resource selection for oviposition, the pygidiales secretions of males and females of D. furcatum show no dissuasive effects on L. cuprina. The results are discussed in the context of the biological behavior of dung beetles and the possibility of using glandular secretions during nesting. / Os besouros roladores da subfamília Scarabaeinae utilizam fezes e carcaças como fonte de alimento e para a reprodução. A natureza efêmera desses recursos dá origem a uma forte competição intra e interespecífica entre os organismos que os utilizam, de modo que rolar o alimento é um mecanismo e de realocação do recurso para evitar a competição. Os principais concorrentes interespecíficos dos besouros roladores são os dípteros, incluindo os da família Calliphoridae. Para prevenir ataques de seu alimento por moscas, os besouros roladores podem cobrir a esfera com uma camada de terra. No entanto, isso parece não ser o único mecanismo, já que durante a rolagem podem secretar substâncias que impregnam na bola e que, possivelmente, agem como defesa química contra esses concorrentes. Assim, o presente estudo investigou o efeito de bolas de alimento roladas e das secreções pigidiais produzidas pelo besouro rolador copro-necrófago Deltochilum furcatum sobre o a oviposição de Lucilia cuprina, uma mosca com preferência de postura de ovos em carniça. Os resultados mostraram que, durante a rolagem do alimento, machos e fêmeas de D. furcatum impregnam substâncias à esfera de alimento que afeta significativamente a oviposição de L. cuprina. A secreção pigidial do macho apresentou um efeito dissuasório, afetando a oviposição de L. cuprina em comparação com a secreção pigidiA secreção pigidial do macho apresentou um efeito dissuasório, afetando a oviposição de L. cuprina em comparação com a secreção pigidial da f mea. E c ̃ c ̃ e ıvel a secre ̧ao pigidial aja em conjunto com outrasal da fêmea. É possível que a secreção pigidial aja em conjunto com outras secreções produzidas por furcatum atuando como alomônios na oviposição de L. cuprina e de outros possíveis competidores. Em situações onde não há escolha dos recursos para a oviposição, L. cuprina não demonstra um efeito dissuasivo às secreções pigidiais de machos e fêmeas de D. furcatum. Os resultados são discutidos no contexto do comportamento biológico dos besouros roladores e da possível utilização de secreções glandulares durante a nidificação.