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[Beta]- aminothiols and the regulation of hepatic oxalate production / Paul Wayne Baker.Baker, Paul Wayne January 1995 (has links)
Bibliography :leaves 149-172. / vii, 172,[60] leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The investigations centre on the use of [beta]-aminothiols (cysteine, cysteamine and penicillamine) to decrease endogenous oxalate production by forming adducts with glyoxylate, the immediate precursor of oxalate. They indicate that cysteine delivery drugs like OTC have the potential to aid in management of calcium oxalate stone disease, thereby reducing endogenous oxalate production and urinary oxalate excretion. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 1995?
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Ανάπτυξη μεθοδολογίας για την εις βάθος συσσωμάτωση χαλαρών εδαφώνΑρβανίτη, Ελένη 20 October 2009 (has links)
Μελετάται η ανάπτυξη μεθόδου για την εις βάθος συσσωμάτωση χαλαρών εδαφών που προορίζονται για οικοδόμηση καθώς και για εδάφη περιοχών που υποφέρουν από κατολισθήσεις. Με την ίδια κατά βάση μεθοδολογία, επιχειρείται η επίτευξη στεγανοποίησης κατασκευών σκυροδέματος που υποφέρουν από διαρροές ή από υγρασία και είναι αναγκαία η άμεση αποκατάσταση τους με χαμηλό κόστος. Και στις δύο περιπτώσεις η νέα μεθοδολογία αποτελεί καινοτομία φιλική στο περιβάλλον. Για το σκοπό αυτό προτάθηκε ένα σύστημα υδατοδιαλυτών χημικών με σκοπό την επί τόπου καταβύθιση ενός δυσδιάλυτου άλατος στα τοιχώματα των πόρων του σκυροδέματος και την μείωση της υδατοπερατότητας του υλικού. Το προτεινόμενο άλας ήταν το οξαλικό ασβέστιο (CaC2O4).
Το οξαλικό ασβέστιο είναι το κύριο συστατικό των λίθων του ουροποιητικού. Το μονοένυδρο και διένυδρο οξαλικό ασβέστιο έχουν ανιχνευθεί στην πατίνα, το επιφανειακό επίστρωμα που έχει σχηματιστεί σε αρχαία μνημεία, αγάλματα και φυσικά σχηματισμένους βράχους. Μέχρι σήμερα θεωρείται ότι το στρώμα αυτό οξαλικού ασβεστίου στην επιφάνεια των αρχαίων μνημείων, παίζει σημαντικό προστατευτικό ρόλο για την επιφάνεια που καλύπτει.
Αρχικά έγινε συστηματική μελέτη της αυθόρμητης καταβύθισης του οξαλικού ασβεστίου σε αντιδραστήρες διαλείποντος έργου. Οι πειραματικές συνθήκες ήταν τέτοιες που να προσομοιάζουν τις συνθήκες κατά την εφαρμογή των χημικών στο σκυρόδεμα (θερμοκρασία 25°C, pH=6.5 και 10). Μελετήθηκε η επίδραση συνθετικών κρυστάλλων μονοένυδρου οξαλικού ασβεστίου (COM) και κόκκων τσιμεντοκονιάματος. Σε όλες τις περιπτώσεις ανιχνεύθηκε το COM στην καταβυθιζόμενη φάση. Οι κρύσταλλοι αναπτύσσονται πάνω στους κόκκους τους τσιμεντοκονιάματος και σχηματίζουν μεγάλα συσσωματώματα. Το μέγεθός τους (8-10 μm) και το σχήμα τους (εξαγωνικό πρισματικό) είναι χαρακτηριστικά που ευνοούν το οξαλικό ασβέστιο να παίξει το ρόλο συνδετικού υλικού σε πορώδη μέσα. Ο κύριος μηχανισμός κρυσταλλικής ανάπτυξης είναι η επιφανειακή διάχυση των δομικών μονάδων στην επιφάνεια του κρυστάλλου.
Τέλος, μελετήθηκε η επί τόπου καταβύθιση του COM σε δοκίμια τσιμεντοκονιάματος. Τα διαλύματα εισέρχονταν στο εσωτερικό του δοκιμίου με τη βοήθεια της βαρύτητας. Στα δοκίμια τσιμεντοκονιάματος πραγματοποιήθηκαν πειράματα τριχοειδούς εισρόφησης νερού και μηχανικής επιφανειακής απότριψης. Κατεργασία του τσιμεντοκονιάματος με διάλυμα οξαλικού νατρίου σε υψηλές θερμοκρασίες, φαίνεται να μειώνει την εισρόφηση του νερού. / A new environmental friendly method, for the stabilization of loose soils to be used as building sites and for the amelioration of the properties of concrete constructions suffering from water leaks or humidity has been developed. The novelty of the proposed method is lying on the in situ precipitation of calcium oxalate monohydrate (COM) within the porous structure of soil or on the pore walls of the construction material (concrete) in order to minimize water leakage. Calcium oxalate, encountered often in kidney stones in the form of COM, is notorious for the formation of hard, non-porous aggregates which adhere tenaciously onto substrates. Calcium oxalate in the form of a protective patina is often met as surface layer in marbles or limestones. Mechanistic information concerning the formation of COM in supersaturated solutions may be obtained in seeded growth experiments. In these experiments, supersaturated solutions are seeded either with seed crystals of the same under investigation salt or of any other insoluble solid material on which the heterogeneous formation of the salt of interest may take place. Among the objectives of the present work was to investigate the role of concrete grains on the nucleation and crystal growth of COM. The analysis of the kinetics data showed that the prevalent mechanism for COM precipitation was surface diffusion. In all cases the only crystalline phase forming in the supersaturated solutions was identified as COM. In the second part of the present work the in situ precipitation of COM into mortar samples was studied. SEM analysis showed that crystallization indeed took place within the pores of the concrete. Best results in terms of waterproofing of concrete material were obtained in the case of treating concrete surfaces with sodium oxalate solution at high temperature.
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Estudo do teor de ácido oxálico em hortaliças e frutos, seu potencial de cristalização in vitro e caracterização morfológica de cristais de oxalato de cálcio / The study of oxalic acid content in vegetables and fruits, its in vitro crystallization potential and morphological characterization of calcium oxalate crystalsSartarelli, Natália Cecília 03 July 2018 (has links)
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Previous issue date: 2018-07-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivos: Analisar quali e quantitativamente algumas hortaliças e frutos, quanto ao teor de ácido oxálico e avaliar o comportamento químico do ácido oxálico frente a agentes indutores e inibidores de cristalização in vitro. Métodos: A análise qualitativa morfológica de cristais de oxalato de cálcio foi feita sob microscopia ótica de luz polarizada e, quantitativamente foram determinados por método espectrofotométrico, os teores de ácido oxálico após extração com água e ácido clorídrico. Foram realizados também ensaios de indução de cristalização com cloreto de cálcio e inibição com sulfato de magnésio e citrato de sódio, respectivamente. Resultados: Foram identificados cristais de oxalato de cálcio do tipo drusas na alface; ráfides no cará e kiwi e, na rúcula e laranja não foi possível identificar o tipo morfológico do cristal presente. No estudo quantitativo observou-se diferença significativa entre as médias obtidas nas extrações aquosa e ácida somente para o cará, sendo superior na extração ácida. Observou-se ainda significância somente para a couve no ensaio quantitativo de cristalização; o acréscimo de sulfato de magnésio como agente inibidor da cristalização não foi significativo para todas as amostras avaliadas no estudo, no entanto, com o acréscimo de citrato de sódio houve aumento do conteúdo de ácido oxálico para o cará, inhame, laranja e kiwi. No estudo qualitativo dos ensaios de cristalização com cloreto de cálcio em microscopia ótica de luz polarizada observou-se presença de arranjos cristalinos; no ensaio com sulfato de magnésio observou-se presença de cristais poliédricos no kiwi, couve e laranja e, com o acréscimo de citrato de sódio observou-se presença de cristais menores somente em alface, cará, couve e inhame. Conclusão: Neste contexto, os teores de oxalato nas hortaliças e frutos estudados apresentam variações próprias conforme a matriz constitucional e, podem ser modificados com o acréscimo de cálcio e citrato. / Objectives: Analyze qualitatively and quantitatively some vegetables and fruits, regarding in the content of oxalic acid and evaluate the chemical behavior of the oxalic acid against inducers and inhibitors agents of the in vitro crystallization. Methods: The qualitative morphological analysis of calcium oxalate crystals was done under optical microscopy of polarized light and, quantitatively, the values of oxalic acid after extraction with water and hydrochloric acid were determined by spectrophotometric method. Tests inducting the crystallization with calcium chloride and inhibitioning with magnesium sulphate and sodium citrate, respectively, were also performed. Results: Druses calcium oxalate crystals were identified in lettuce; raphides in yam and kiwifruit; and in the arugula and orange it was not possible to identify the morphological type of the present crystal. In the quantitative study a significant difference was observed between the averages obtained in the aqueous and acid extractions only for the yam, being superior in the acid extraction. It was also observed a significance only for the wild cabbage in quantitative crystallization test. The addition of magnesium sulphate as a crystallization inhibitor was not significant for all the samples evaluated in the study. However, with the addition of sodium citrate there was an increase in the content of oxalic acid for yam, taro, orange and kiwifruit. Crystalline arrangements were observed in the qualitative study of crystallization tests with calcium chloride under optical microscopy of polarized light; in the test with magnesium sulphate it was noticed the presence of polyhedral crystals in kiwifruit, wild cabbage and orange and, with the addition of sodium citrate, small crystals were present only in lettuce, taro, wild cabbage and yam. Conclusion: In this context, oxalate contents in the vegetables and fruits that were studied have their own variations according to the constitutional matrix and, the oxalate content can be modified with the addition of calcium and citrate.
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Lichens as agents of biodeteriorationSeaward, Mark R.D. January 2015 (has links)
No / One of the major roles lichens play in shaping the natural world, both physically and biologically, is as agents in soil development: formerly considered only in a geological context, recent research has shown that they are capable of biodeteriorating stone substrata within a relatively short timescale. Chemical alteration of the substratum is achieved by the disruptive action of many species, particularly those capable of producing an oxalate at the thallus–substratum interface . The oxalate contributes significantly to the bulk and composition of the thallus itself and persists as an obvious encrustation after the lichen’s death. In the past, these disfiguring oxalate residues on ancient monuments have been variously interpreted as resulting from former mechanical/chemical renovation treatments, atmospheric pollution , and climatic weathering. The origin and nature of oxalate accretions, the factors involved in pedogenesis , and the development of lichen mosaics are reviewed. Aesthetic disfigurement versus physical damage to stonework is considered, and various aspects of stonework conservation are discussed.
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Síntese, atividade antiurolítica, e estudos de biotransformação de ácidos galoilquínicos de espécies de Copaifera por fungos filamentosos / Synthesis, antiurolithic activity, and biotransformation studies of galloylquinic acids from Copaifera species by filamentous fungiAbdelsalam, Mohamed Ahmed Mohamed Hamed 31 August 2018 (has links)
Calculo renal, também conhecido como urolitíase, é comum com uma taxa de prevalência estimada global recente de 14,8%, a qual parece estar aumentando, com uma taxa de recorrência em cinco anos de até 50%. As várias atividades biológcas promissoras de extratos de plantas ricas em ácidos galolquínicos, como as folhas das espécies de Copaifera, levaram nosso interesse em sintetizar o éster metílico do ácido 3,4,5-tri-O-galoilquinico trissubstituído (TGAME), com o objetivo de desenvolver um composto com potencial para prevenção de cálculos renais. A síntese total incluiu seis etapas a partir dos ácidos quínico e gálico disponíveis comercialmente. O passo-chave na via sintética foi a esterificação de Steglich viável do quinato de metila com ácido 3,4,5-tribenziloxibenzóico usando diciclo-hexilcarbodiimida e N, N-(dimetilamino)piridina como reagentes de acoplamento. As estruturas químicas do composto final e seus intermediários sintéticos foram elucidados por métodos espectroscópicos, espectrométricos e espectrofotométricos de análises. O efeito potencial do composto sobre a ligação de cristal monoidratado de oxalato de cálcio (COM) à superfície de células de rim caninas tipo I de Madin-Darby (MDCKI) e o crescimento de cristais em modelo de túbulos Malpighi de Drosophila melanogaster foi investigado. As quantidades de membrana, citosólica e total de Annexina A1 (ANXA1), Alfa-enolase e HSP90 foram examinadas por análise de transferência de Western após fracionamento subcelular, as quais foram confirmadas por coloração por imunofluorescência de células cultivadas. O pré-tratamento de células MDCKI com TGAME por até 6 h diminuiu significativamente a ligação de cristal COM de uma maneira dependente da concentração. O TGAME (50 ?M) inibiu significativamente a expressão superficial de ANXA1 por microscopia de imunofluorescência, enquanto o ANXA1 intracelular aumentou. A análise de Western Blot confirmou alterações de expressão de ANXA1 na membrana e frações citosólicas de células tratadas com os compostos, enquanto a ANXA1 de células inteiras permaneceu inalterada. O TGAME também diminuiu significativamente o tamanho, o número e o crescimento de cristais de COM induzidos em um modelo de túbulos Malpighi de Drosophila melanogaster, o qual apresentou também potente atividade antioxidante em um ensaio de DPPH. Adicionalmente, realizamos estudos de biotransformação de derivados do ácido galoilquínico, utilizando fungos filamentosos, para prever seus comportamentos farmacocinéticos. Os resultados mostraram que os ácidos galoilquínicos das folhas de Copaifera lucens (fração n-butanólica, BF) foram transformados por Aspergillus alliaceus em um metabólito majoritário, o ácido 3-O-metil gálico (M1), que é um dos metabolitos conhecidos do ácido gálico estudado em humanos. O produto biotransformado foi identificado por UPLC-MS/MS. O pré-tratamento de células MDCKI com BF e seu produto transformado por 3 h diminuiu significativamente a ligação de cristal COM a estas células em concentrações de 50 ?g/mL e 5 ?M, respectivamente. Os compostos reduziram significativamente a expressão superficial das ANXA1 e HSP90 (proteínas de ligação COM) como evidenciado por microscopia de imunofluorescência, enquanto o nível intracelular aumentou. A análise por Western blot confirmou estas alterações nas frações de membrana e citosol das células tratadas com estes compostos, enquanto as células inteiras permaneceram inalteradas. M1 também apresentou atividade antioxidante promissora no ensaio DPPH. / Renal stone disease, also known as urolithiasis, is common with a recent overall estimated prevalence rate of 14.8% that appears to be rising, with a five-year recurrence rate of up to 50%. The promising diverse bioactivities of plant extracts rich in galloylquinic acids such as Copaifera species leaves prompted our interest to synthesize the tri-substituted 3,4,5-tri-O-galloylquinic acid methyl ester (TGAME), with the goal of developing a lead compound for kidney stone prevention. The total synthesis included six steps starting from commercially available quinic and gallic acids. The key step in the synthetic pathway was through Steglich esterification of methyl quinate with 3,4,5-tribenzyloxybenzoic acid using dicyclohexylcarbodiimide and N,N-(dimethylamino) pyridine as the coupling reagents. The chemical structures of the final compound and its synthetic intermediates were elucidated by spectroscopic, spectrometric and spectrophotometric methods of analyses. The potential effect of the compound on calcium oxalate monohydrate (COM) crystal binding to the surface of Madin-Darby Canine Kidney Cells type I (MDCKI) and crystal growth in a Drosophila melanogaster Malpighian tubule model were investigated. Membrane, cytosolic and total Annexin A1 (ANXA1), ?-enolase and HSP90 amounts were examined by Western blot analysis after subcellular fractionation, then confirmed by immunofluorescence staining of cultured cells. Pretreatment of MDCKI cells with TGAME for up to 6 h significantly diminished COM crystal-binding in a concentration-dependent manner. TGAME (50 ?M) significantly inhibited ANXA1 surface expression as evident by immunofluorescence microscopy, whereas intracellular ANXA1 increased. Western blot analysis confirmed ANXA1 expression changes in the membrane and cytosolic fractions of compound-treated cells, whereas the whole cell ANXA1 remained unchanged. TGAME also significantly decreased the size, number, and growth of COM crystals induced in a Drosophila melanogaster Malpighian tubule model, and possessed a potent antioxidant activity in a DPPH assay. We also have performed a biotransformation study of galloylquinic acid compounds using filamentous fungi to predict their pharmacokinetic behaviors. The results showed that galloylquinic acids from Copaifera lucens leaves (n-butanolic fraction, BF) were transformed by Aspergillus alliaceus into one major metabolite 3-O-methyl gallic acid (M1), which is one of the known metabolites of gallic acid studied in humans. The biotransformed product was identified by UPLC-DAD-MS/MS and 1H NMR. Pretreatment of MDCKI cells with BF (50 ?g/mL) and its transformed product M1 (5 ?M) for 3 h significantly diminished COM crystal-binding to these cells. The compounds significantly reduced surface expression of ANXA1 and HSP90 (COM-binding proteins) as evidence by immunofluorescence microscopy, whereas the intracellular level increased. Western blot analysis confirmed these changes in membrane and cytosolic fractions of compound-treated cells, whereas whole cells remained unchanged. M1 also showed a promising antioxidant activity in DPPH assay.
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Espectroscopia Raman aplicada ao estudo de pigmentos em bens culturais: I - pinturas rupestres / Raman spectroscopy applied to the study of pigments in cultural goods: I - rupestrian paintingsLopes, Francisco Nascimento 14 March 2005 (has links)
Neste estudo amostras coletadas de pinturas rupestres foram analisadas para identificação do material utilizado; análises da sua interação e de processos eventuais de degradação, além de atribuições quanto à sua origem, foram também feitas através da espectroscopia Raman. Pigmentos encontrados em pinturas rupestres em Minas Gerais foram identificados, junto a produtos de degradação microbiológica. A partir dos resultados, foi feita uma caracterização da transformação de desidratação do pigmento amarelo de goetita (α-FeOOH) a hematita (α-Fe2O3) por espectroscopia Raman na tentativa de contextualizá-la no problema da origem da hematita encontrada nas representações. Foram identificados os pigmentos calcita (CaCO3) para o branco, carvão vegetal para o preto, goetita (α-FeOOH) para o amarelo e hematita (α-Fe2O3) para o vermelho, que constituem basicamente a paleta de cores desse período. Produtos de degradação microbiológica foram identificados por espectroscopia Raman e no infravermelho por ATR como sendo whewellita (CaC2O4.H2O) e weddelita(CaC2O4.2H2O). A transformação topotática de goetita a hematita por aquecimento foi acompanhada por espectroscopia Raman in situ e ex-situ e infravermelho, na tentativa de caracterizar o processo quanto às fases formadas, possíveis marcadores, de maneira a complementar resultados da literatura que utilizaram outras técnicas, como difração de raio-X (XRD) e microscopia eletrônica de transmissão (TEM). Esse estudo foi realizado na tentativa de determinar a existência de possível manipulação térmica desses materiais como sugerido em trabalhos anteriores. Em particular, nos espectros Raman, o comportamento diferenciado da banda em torno de 660 cm-1 e a maior largura das bandas de uma maneira geral, presentes na chamada hematita desordenada, perfil que as amostras naturais coletadas apresentam, são marcadores do efeito de temperatura, uma vez que parecem estar ligados mais estreitamente ao deslocamento catiônico dos íons Fe do que ao rearranjo da gaiola octaédrica de oxigênios ao redor destes, durante a transição a partir de goetita. Esse comportamento dos espectros Raman é confirmado pelos padrões dos difratogramas de raio-X. Concluiu-se que esse desordenamento, entretanto, não é causado somente pela temperatura e, dessa forma, não pode ser usado para atestar inequivocamente como sendo resultado de processamento dos materiais (goetita). / This dissertation reports the investigation carried out on samples collected from rupestrian paintings, aiming at the identification of materials used, their interaction and degradation. The technique of choice was Raman microscopy as it is a non-destructive tool, which provides the spatial resolution necessary for the study of heterogeneous samples. Pigments were identified together with products of microbiological degradation. Thermal convertion of goethite (yellow) to hematite (red) was followed by Raman spectroscopy in a tentative to address the issue of the provenance of red pigments (natural hematite or heated goethite) found in the paintings. White pigments were identified as calcite (CaCO3), whereas charcoal was used as black, goethite (α-FeOOH) as yellow and hematite (α-Fe2O3) as red. These pigments are usually found in rock art palletes. Degradation products from microbiological activity were identified by Raman microscopy and ATR infrared spectroscopy as being whewellite (CaC2O4.H2O) and weddelite (CaC2O4.2H2O). The topotatic transition from goethite to hematite was followed by in situ and ex-situ Raman and infrared spectroscopy, regarding the characterization of the phases formed, possible markers, aiming to complement the previous results reported in the literature using other techniques such as X-ray diffractometry (XRD) and transmission eletron microscopy (TEM). The main goal of the study of temperature effect on the Raman spectrum of goethite was to determine whether hematite was used as found in nature or was obtained by goethite heating as suggested in previous investigations. Particularly, the behavior of the 660 cm-1 band and a larger linewidth for bands in the spectrum, present in the disordered hematite and in the red pigments analysed, are markers of the thermal processing. These features seem to be related to the movement of iron ions and to the rearrangment of the octahedrical cage formed by oxygen atoms around them. Such conclusions are in agreement with X-ray data. Unfortunately, temperature is not the only factor to cause such structural disorder and, hence, it cannot be used as an unequivocal marker of thermal processing.
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Caracterização de cristais em ectomicorrizas de eucalipto, acúmulo de cálcio e produção de ácidos orgânicos pelo micélio / Characterization of crystals in eucalypt ectomycorrhizas, calcium accumulation and organic acids production by the myceliumPylro, Victor Satler 07 July 2010 (has links)
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Previous issue date: 2010-07-07 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Ectomycorrhizal fungi associated with eucalypt roots may induce the storage of calcium in the form of calcium oxalate crystals in the root system of the host plant. Despite of the great demand for calcium by the plants of this genus and the low calcium availability in Brazilian soils, little is known about the calcium storage capacity and organic acids efflux displayed by ectomycorrhizal depending on the availability of this element. Thus, this study aimed to characterize calcium crystals in ectomycorrhizas of Eucalyptus sp., their distribution, morphology and chemical composition, and to assess the ability of ectomycorrhizal fungi to accumulate calcium and produce organic acids when grown under different concentrations of calcium in the growth medium. In ectomycorrhizas of Eucalyptus sp., the crystals were observed inside root cortical cells. Three different distribution patterns were observed and classified as regular, irregular or smooth. The scanning electron microscopy combined with energy dispersive X-ray microprobe analysis allowed to classify the morphologies of the predominant crystals as granules and concretions, although other morphological types have also been highlighted. Calcium, oxygen and carbon are the major constituents of these crystals, which were characterized as calcium oxalate crystals. In general, ectomycorrhizal fungi exhibited a pattern of calcium accumulation in mycelium responding positively to the increase of the element concentration in the growth medium. However, the concentration of calcium in the medium does not seem to influence the production of fungal biomass. Under conditions of lower calcium concentration in the medium, the isolates had higher calcium utilization efficiency. The acetic/gluconic, butyric, oxalic and citric acids were detected in the growth medium of ectomycorrhizal isolates evaluated. The concentration of calcium in the medium influenced exudation of acids acetic/gluconic, butyric and oxalic by the isolate Pisolithus sp. PT06, which also showed the highest production of these compounds in comparison to others. This, may be related to lower accumulation of fungal biomass exhibited by this isolate. The concentration of butyric acid in the growth medium of isolate Pisolithus tinctorius PTFRA was higher when the concentration of calcium was smaller, similar to isolate Pisolithus sp. PT06. This is the first report about the detailed morphology and chemical constitution of predominant crystals in ectomycorrhizal of eucalypts. Moreover, the results corroborate the role of ectomycorrhizal fungi in calcium acquisition from soil and suggest that different isolates may have different capacities of cycling calcium, either by biomass accumulation or efflux of organic acids. / Fungos ectomicorrízicos associados à raízes de eucalipto podem induzir o armazenamento de cálcio sob a forma de cristais de oxalato de cálcio no sistema radicular da planta hospedeira. Apesar da grande demanda por cálcio pelas plantas desse gênero e a baixa disponibilidade em solos brasileiros, pouco se sabe sobre as capacidades de armazenamento de cálcio e efluxo de ácidos orgânicos exibidas por fungos ectomicorrízicos em função da disponibilidade do elemento. Sendo assim, este trabalho teve por objetivo caracterizar cristais de cálcio presentes em ectomicorrizas de Eucalyptus sp., quanto a sua distribuição, morfologia e composição química, além de avaliar a capacidade de fungos ectomicorrízicos em acumular cálcio e produzir ácidos orgânicos quando cultivados sob diferentes concentrações do elemento. Nas ectomicorrizas de Eucalyptus sp., os cristais foram evidenciados no interior de células corticais radiculares. Três diferentes padrões de distribuição foram observados e classificados como regular, irregular ou homogêneo. A Microscopia Eletrônica de Varredura associada a microssonda de análise de energia dispersiva de raios-X permitiu classificar as morfologias predominantes dos cristais como grânulos e concreções, embora outros tipos morfológicos também tenham sido evidenciados. Cálcio, oxigênio e carbono são os principais elementos constituintes desses cristais, que diante de todos os resultados obtidos foram seguramente caracterizados como cristais de oxalato de cálcio. De modo geral, fungos ectomicorrízicos exibiram um padrão de acúmulo de cálcio no micélio respondendo positivamente ao aumento da concentração do elemento no meio de cultivo. Contudo, a dose de cálcio no meio parece não influenciar a produção de biomassa fúngica. Sob condições de menor concentração de cálcio no meio, os isolados apresentaram maior eficiência de utilização de cálcio. Os ácidos acético/glucônico, butírico, oxálico e cítrico foram detectados no meio de cultivo dos isolados ectomicorrízicos avaliados. A dose de cálcio no meio de cultivo influenciou a exsudação dos ácidos acético/glucônico, butírico e oxálico pelo isolado Pisolithus sp. PT06, que também apresentou a maior produção desses compostos em comparação aos demais e isso pode estar relacionado ao menor acúmulo de biomassa fúngica exibido por esse isolado. A concentração do ácido butírico no meio do isolado Pisolithus tinctorius PTFRA foi influenciada pela dose de cálcio, sendo maior onde a concentração de cálcio era menor, padrão semelhante ao do isolado Pisolithus sp. PT06. Este é o primeiro relato sobre a morfologia detalhada e constituição química de cristais predominantes em ectomicorrizas de eucalipto. Além disso, os resultados apresentados corroboram o papel de fungos ectomicorrízicos na aquisição de cálcio do solo e sugerem que diferentes isolados podem apresentar capacidades distintas de atuação nos processos envolvendo a ciclagem do cálcio, seja pelo efluxo de ácidos orgânicos e/ou acúmulo na biomassa.
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Fatores litog?nicos em pacientes com lit?ase urin?ria de Fortaleza, Cear?Silva, S?lvia Fernandes Ribeiro da 08 October 2010 (has links)
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Previous issue date: 2010-10-08 / Lithiasis is considered a public health issue due to its high
prevalence and rates of recurrence.
Objective: To identify risk factors for lithiasis in kidney stone patients from
Fortaleza, Brazil.
In the first stage of the study, the medical records of
197 patients with urinary lithiasis covering the period 1996 2006 were analyzed
with regard to clinical and metabolic data. In the second stage, 340 kidney
stones were submitted to morphological examination under 10x magnification.
According to the external morphology and the cut surface, the stones were
classified as pure or mixed, and major and minor components were identified.
In addition, the stone fragments of 25 patients treated with
lithotripsy were submitted to morphological analysis. In the third stage, a
subsample of 50 stones was used in a double-blind comparison of
morphological and chemical findings. Results were expressed as concordant,
partly concordant (discordant for minor components) or discordant (discordant
for major components).
The average age of first symptoms was 35.8?13.3 years, with no
significant difference between the genders. The male/female ratio was 1:1.7.
Recurrence was reported in 53.3% of cases. The main metabolic changes
observed were hypernatriuria (80.7%), hypercalciuria (48.7%), low urine volume
(43.7%), hyperoxaluria (30.5%) and hyperuricosuria (17.3%). Pure stones
represented 34.7% of the total sample of 340 stones. The most common route
of elimination was spontaneous for pure stones (49.1%) and surgical for mixed
stones (50.5%). Pure stones consisted most frequently of calcium oxalate
(OxCa) (59.3%) and uric acid (UA) (23.7%), the former prevalent in women, the
latter prevalent in men. The most frequently observed component in mixed
stones was OxCa (67.1%), followed by carbapatite (11.2%) and struvite (7.9%).
The main components were OxCa and UA for men, and carbapatite and struvite
for women. Nearly half (48%) the 25 analyzed fragments were pure, consisting
of calcium oxalate dihydrate (COD) (56%), calcium oxalate monohydrate (COM)
(48%), phosphate (32%) and UA (20%). Four patients (16%) had infectious
stones. In the chemical analysis of the subsample of 50 stones, the most
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frequently observed major components were calcium (70%), oxalate (66%),
ammonium (56%), urate (28%) and carbonate (24%). In the morphological
analysis, the main components were calcium and magnesium phosphate (32%),
COM (24%), UA (20%), COD (18%) and cystine (6%). Morphological and
chemical findings were totally concordant for 38% of the stones, partly
concordant in 52% and discordant in 10%.
Conclusion: The risk factors for lithiasis in kidney stone patients from Fortaleza
(Brazil) were hyperoxaluria, hypercalciuria with or without hypernatriuria,
hyperuricosuria and low urine volume / A lit?ase urin?ria ? um problema de sa?de p?blica pela elevada
preval?ncia e recorr?ncia.
Objetivo: O objetivo do presente estudo foi determinar os fatores litog?nicos
em pacientes com lit?ase urin?ria de Fortaleza, Cear?.
O estudo foi dividido em tr?s fases: na primeira, realizouse
estudo documental de prontu?rios de 197 pacientes com lit?ase urin?ria
atendidos entre 1996 e 2006, para a an?lise de dados cl?nicos e avalia??o
metab?lica. Na segunda fase foi realizada uma avalia??o morfol?gica de 340
c?lculos urin?rios, classificando-os como puro ou misto e os componentes em
majorit?rios ou minorit?rios. Foi tamb?m avaliado fragmentos de c?lculos de 25
pacientes tratados com litotripsia. Na terceira fase utilizou-se uma amostra de
50 c?lculos para um estudo duplo-cego comparando a an?lise morfol?gica e a
an?lise qu?mica. Os resultados foram considerados como concordantes,
parcialmente concordantes (componentes minorit?rios discordantes) ou
discordantes (componentes majorit?rios discordantes).
A m?dia de idade dos 197 pacientes no primeiro sintoma foi 35,8
? 13,3 anos, n?o houve diferen?a entre os g?neros. A rela??o homem:mulher
foi de 1:1,7, 53,3% eram recorrentes. As principais altera??es metab?licas
foram hipernatri?ria (80,7%), hipercalci?ria (48,7%), volume urin?rio baixo
(43,7%), hiperoxal?ria (30,5%) e hiperuricos?ria (17,3%). Entre os 340 c?lculos
analisados, 34,7% foram puros. A via de elimina??o mais comum dos c?lculos
puros foi a espont?nea (49,1%) e a dos mistos foi a cir?rgica (50,5%). Os
c?lculos mais freq?entes foram o oxalato de c?lcio (OxCa=59,3%) e ?cido ?rico
(AU=23,7%), sendo o primeiro mais comum nas mulheres e o segundo nos
homens. Entre os c?lculos mistos, o OxCa foi o principal componente (67,1%),
seguido da carbapatita (11,2%) e estruvita (7,9%). Os principais componentes
nos homens foram o OxCa e AU, enquanto que nas mulheres foram a
carbapatita e estruvita. Entre os 25 fragmentos de c?lculos analisados, 48%
foram puros. Os componentes encontrados foram: OxCa dihidratado-COD
(56%), OxCa monohidratado-COM (48%), fosfato (32%), AU (20%). Quatro
pacientes (16%) apresentaram c?lculo de infec??o. Na an?lise qu?mica dos 50
c?lculos urin?rios os principais componentes majorit?rios foram c?lcio (70%),
xvi
oxalato (66%), am?nio (56%), urato (28%) e carbonato (24%), enquanto que na
morfol?gica foram fosfato de c?lcio e magnesiano (32%), COM (24%), AU
(20%), COD (18%) e cistina (6%). Concord?ncia total foi observada em 38%,
parcial em 52% e discord?ncia em 10%.
Conclus?o: Os fatores de risco litog?nicos na regi?o de Fortaleza foram
hiperoxal?ria, hipercalci?ria com ou sem hipernatri?ria, hiperuricos?ria e
volume urin?rio reduzido
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Espectroscopia Raman aplicada ao estudo de pigmentos em bens culturais: I - pinturas rupestres / Raman spectroscopy applied to the study of pigments in cultural goods: I - rupestrian paintingsFrancisco Nascimento Lopes 14 March 2005 (has links)
Neste estudo amostras coletadas de pinturas rupestres foram analisadas para identificação do material utilizado; análises da sua interação e de processos eventuais de degradação, além de atribuições quanto à sua origem, foram também feitas através da espectroscopia Raman. Pigmentos encontrados em pinturas rupestres em Minas Gerais foram identificados, junto a produtos de degradação microbiológica. A partir dos resultados, foi feita uma caracterização da transformação de desidratação do pigmento amarelo de goetita (α-FeOOH) a hematita (α-Fe2O3) por espectroscopia Raman na tentativa de contextualizá-la no problema da origem da hematita encontrada nas representações. Foram identificados os pigmentos calcita (CaCO3) para o branco, carvão vegetal para o preto, goetita (α-FeOOH) para o amarelo e hematita (α-Fe2O3) para o vermelho, que constituem basicamente a paleta de cores desse período. Produtos de degradação microbiológica foram identificados por espectroscopia Raman e no infravermelho por ATR como sendo whewellita (CaC2O4.H2O) e weddelita(CaC2O4.2H2O). A transformação topotática de goetita a hematita por aquecimento foi acompanhada por espectroscopia Raman in situ e ex-situ e infravermelho, na tentativa de caracterizar o processo quanto às fases formadas, possíveis marcadores, de maneira a complementar resultados da literatura que utilizaram outras técnicas, como difração de raio-X (XRD) e microscopia eletrônica de transmissão (TEM). Esse estudo foi realizado na tentativa de determinar a existência de possível manipulação térmica desses materiais como sugerido em trabalhos anteriores. Em particular, nos espectros Raman, o comportamento diferenciado da banda em torno de 660 cm-1 e a maior largura das bandas de uma maneira geral, presentes na chamada hematita desordenada, perfil que as amostras naturais coletadas apresentam, são marcadores do efeito de temperatura, uma vez que parecem estar ligados mais estreitamente ao deslocamento catiônico dos íons Fe do que ao rearranjo da gaiola octaédrica de oxigênios ao redor destes, durante a transição a partir de goetita. Esse comportamento dos espectros Raman é confirmado pelos padrões dos difratogramas de raio-X. Concluiu-se que esse desordenamento, entretanto, não é causado somente pela temperatura e, dessa forma, não pode ser usado para atestar inequivocamente como sendo resultado de processamento dos materiais (goetita). / This dissertation reports the investigation carried out on samples collected from rupestrian paintings, aiming at the identification of materials used, their interaction and degradation. The technique of choice was Raman microscopy as it is a non-destructive tool, which provides the spatial resolution necessary for the study of heterogeneous samples. Pigments were identified together with products of microbiological degradation. Thermal convertion of goethite (yellow) to hematite (red) was followed by Raman spectroscopy in a tentative to address the issue of the provenance of red pigments (natural hematite or heated goethite) found in the paintings. White pigments were identified as calcite (CaCO3), whereas charcoal was used as black, goethite (α-FeOOH) as yellow and hematite (α-Fe2O3) as red. These pigments are usually found in rock art palletes. Degradation products from microbiological activity were identified by Raman microscopy and ATR infrared spectroscopy as being whewellite (CaC2O4.H2O) and weddelite (CaC2O4.2H2O). The topotatic transition from goethite to hematite was followed by in situ and ex-situ Raman and infrared spectroscopy, regarding the characterization of the phases formed, possible markers, aiming to complement the previous results reported in the literature using other techniques such as X-ray diffractometry (XRD) and transmission eletron microscopy (TEM). The main goal of the study of temperature effect on the Raman spectrum of goethite was to determine whether hematite was used as found in nature or was obtained by goethite heating as suggested in previous investigations. Particularly, the behavior of the 660 cm-1 band and a larger linewidth for bands in the spectrum, present in the disordered hematite and in the red pigments analysed, are markers of the thermal processing. These features seem to be related to the movement of iron ions and to the rearrangment of the octahedrical cage formed by oxygen atoms around them. Such conclusions are in agreement with X-ray data. Unfortunately, temperature is not the only factor to cause such structural disorder and, hence, it cannot be used as an unequivocal marker of thermal processing.
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