Spelling suggestions: "subject:"file."" "subject:"pile.""
161 |
Avaliação da expressão imuno-histoquímica de proteínas transportadoras biliares em carcinoma hepatocelular e em colangiocarcinoma / Evaluation of immunohistochemical expression of bile transporter proteins in hepatocellular carcinoma and in cholangiocarcinomaCinthya dos Santos Cirqueira Borges 12 July 2017 (has links)
A análise das proteínas transportadoras de compostos biliares, antes restrita à fisiologia e à fisiopatologia de colestases, recentemente passou a incluir neoplasias hepato-biliares. O presente estudo teve como objetivo caracterizar a expressão das proteínas ABC de transporte biliar BSEP, MDR3, MRP2 e MRP3 em amostras retrospectivamente colecionadas de 80 casos de autópsias de carcinoma hepatocelular (CHC) e 56 casos de ressecção cirúrgica de colangiocarcinoma (CC). Áreas representativas das neoplasias foram organizadas em tissue microarrays e submetidas à pesquisa imuno-histoquímica (IHQ) com o anticorpo policlonal anti-BSEP (HPA019035) e os anticorpos monoclonais anti-BSEP (F6), anti-MDR3 (P3 II-26), anti-MRP2 (M2 III-6) e anti-MRP3 (DTX-1) com amplificação de sinal mediante uso de sistema de polímeros curtos conjugados à peroxidase. A comparação entre a positividade das reações imuno-histoquímicas para cada anticorpo e as variáveis anatomopatológicas foi realizada através dos testes de qui-quadrado de Pearson ou Exato de Fisher. A positividade das reações IHQ cujos anticorpos propiciaram melhor distinção do sinal positivo vs coloração inespecífica de fundo e detecção de casos positivos e/ou melhor capacidade de discriminar as duas neoplasias hepáticas foi comparada com a positividade observada para as reações IHQ com os anticorpos anti-CEA policlonal, anti-Hep-par-1 e anti-Arginase-1. A expressão canalicular de BSEP nos CHC foi observada em 77,3% (58/75) com o anticorpo monoclonal e 75,9% (60/79) com o anticorpo policlonal. Não foi detectada associação significativa da expressão de BSEP em relação ao tamanho, número dos nódulos e grau de diferenciação de CHC, tendo apenas sido significativamente reduzida (P < 0,05) tal reação nos casos de padrão arquitetural mais complexo. A reatividade dos CHC para o anticorpo monoclonal anti-BSEP foi aparentemente menor que a obtida com a expressão canalicular de CEA, Hep-par-1 e Arginase-1 no CHC, mas esses valores não atingiram significância estatística. Todos os casos de colangiocarcinoma foram negativos para reações IHQ para pesquisa de BSEP, resultado significativamente diferente (P=0,0001) do obtido com uso do Ac policlonal anti-CEA (padrão circunferencial) e Hep-par-1, não tendo sido demonstrada diferença significativa (P=0,222) da expressão de BSEP e de Arginase-1. A expressão canalicular de MDR3 foi observada em 56,4% (44/78) dos casos de CHC, não tendo sido detectada associação significativa quanto ao tamanho e número de nódulos. Foi observada expressão significativamente menor de MDR3 nos casos de CHC de padrão mais complexo (P=0,009), e nos casos de maior grau histológico (P=0,005). A expressão de MDR3 em CHC foi significativamente menor que a de CEA, Hep-par-1 e Arginase-1 (P < 0,05). Todos os casos de colangiocarcinoma foram negativos para a avaliação da expressão de MDR3, diferindo significativamente em relação a expressão de CEA (P=0,001), mas não em comparação a Hep-par-1 e Arginase-1 (P > 0,05). As reações IHQ para detecção de MRP2 exibiram positividade canalicular em 92,3% dos casos de CHC e em 96,3% nos casos de CC. A detecção da alta expressão de MRP2 no CHC foi constante (P > 0,05) em comparação ao tamanho, número dos nódulos, padrão arquitetural e grau histológico de diferenciação de CHC assim como, também não apresentou associação (P > 0,05) com a localização, padrão de crescimento e grau de diferenciação do CC. A reação IHQ para MRP3 resultou positiva em 15/80 casos de CH (18,8%). A reatividade IHQ para MRP foi detectada em 24/54 (44,5%) de CC. Diferente dos transportadores descritos acima, a expressão de MRP3 foi preferencialmente basolateral. A positividade para MRP3 não variou (P > 0,05) em relação ao número, tamanho dos nódulos, padrão arquitetural (inclusive os sólidos), e grau de diferenciação (inclusive os menos diferenciados). A proteína MRP3 esteve expressa regularmente (P > 0,05) em todos os casos de CC, apresentando-se reduzida apenas no subtipo histológico ductular (P=0,023). Em conclusão, o excelente contraste de reação, a frequência razoavelmente alta de positividade de CHC e a plena negatividade de CC para BSEP levam-nos a recomendar a introdução do anticorpo monoclonal anti-BSEP no painel adotado para o diagnóstico diferencial dessas duas neoplasias. A alta expressão de MRP2 no CHC e no CC é conservada independentemente dos parâmetros anatomopatológicos avaliados. A expressão do transportador MRP3 mostrou variação dentre os subtipos histológicos de CC, aspecto que torna promissoras pesquisas futuras para avaliação mais detalhada da expressão deste marcador nos colangiocarcinomas / The assessment of biliary transporters, previously restricted to the physiology and pathophysiology of cholestasis, has recently included hepato-biliary neoplasms. The present study aimed to characterize the expression of BSEP, MDR3, MRP2 and MRP3 biliary transport proteins in retrospectively collected samples from 80 cases of autopsy of hepatocellular carcinoma (HCC) and 56 cases of surgical resection of cholangiocarcinoma (CC). Representative areas of the neoplasms were organized into tissue microarrays and submitted to immunohistochemical (IHC) reaction with polyclonal antibody anti-BSEP (HPA019035) and monoclonal antibodies anti-BSEP (F6), MDR3 (P3 II-26), MRP2 (M2 III-6) and MRP3 (DTX-1). Signal amplification was achieved with a short polymer system conjugated to peroxidase. The comparison between the positivity of the immunohistochemical reactions for each antibody and the pathological variables was performed using the Pearson chi-square test or the Fisher\'s exact test. The performance of antibodies which provided a better distinction of the positive signal vs nonspecific background staining and yield better discrimination between the two hepatic neoplasms was compared with that achieved with the already accepted HCC markers polyclonal anti-CEA, Hep-par-1 and Arginase-1. The canalicular expression of BSEP in HCC was observed in 77.3% (58/75) with the monoclonal antibody and 75.9% (60/79) with the polyclonal antibody. BSEP expression levels were not significantly different according to tumor size, number of nodules and degree of differentiation. The frequency of positive reaction of HCC cases with the monoclonal anti-BSEP was apparently lower than that achieved with the canalicular expression of CEA, Hep-par-1 and Arginase-1, but these values did not reach statistical significance. All cases of cholangiocarcinoma were negative for IHC reactions to BSEP, which was significantly different (P=0.0001) from the results obtained with polyclonal anti-CEA (circumferential pattern) and Hep-par-1, but not from the resultas achieved with Arginase-1 (P=0.222). The canalicular expression of MDR3 was observed in 56.4% (44/78) of HCC cases. Among histological variables, only the finding of more complex architecture (P=0.009) and higher histological grade (P=0.005) of HCC yielded, significantly lower expression of MDR3. The expression of MDR3 in HCC was significantly lower than that of CEA, Hep-par-1 and Arginase-1 (P < 0.05). All cases of cholangiocarcinoma were negative for the evaluation of MDR3 expression, differing significantly with that achieved with polyclonal anti-CEA (P=0.001) but not with that achieved with Hep-par-1 or with Arginase-1 (P > 0.05). The IHC reactions with the MRP2 antibody exhibited canalicular positivity in 92.3% of HCC cases and 96.3% in CC cases. High expression of MRP2 in HCC was constant (P > 0.05) despite changes in size, number of nodules, architectural pattern and histological degree of HCC differentiation, as well as no association (P > 0.05) with the location, pattern of growth and degree of differentiation of CC. The IHC reaction for MRP3 was positive in 15/80 cases of HCC (18.8%) and in 24/54 (44.5%) of CC. Unlike the carriers described above, the hepatocellular expression of MRP3 was preferentially basolateral. Positivity for MRP3 did not vary (P > 0.05) in relation to number, nodule size, architectural standard (including solids), and degree of differentiation. The MRP3 protein was expressed regularly (P > 0.05) in different presentations of CC, but significant lower frequency of positivity was found in the ductular histological subtype (P=0.023). In conclusion, the excellent signal-to-noise ratio, reasonably high frequency of HCC positivity and full negativity of CC to BSEP lead us to recommend the introduction of the anti-BSEP monoclonal antibody in the panel adopted for the differential diagnosis of these two neoplasms. The high expression of MRP2 in HCC and in CC is conserved independently of the pathological parameters evaluated herein. The frequency of expression of the MRP3 transporter varied among the histological subtypes of CC, which makes promising future research for a more detailed assessment of the expression of this marker in the cholangiocarcinomas
|
162 |
Prevalência, fatores de risco e marcadores bioquímicos em cães com lama biliar diagnosticada por ultrassonografia / Prevalence, risk factors and biochemical markers in dogs with ultrasound diagnosed biliary sludgeSecchi, Priscila January 2011 (has links)
A lama biliar em cães é considerada um achado incidental, sendo frequentemente identificada durante ultrassonografias abdominais como sedimento ecogênico de baixa amplitude sem sombra acústica e com mobilidade gravidade dependente. Em humanos, a presença de lama biliar é considerada anormal e está associada a diversas situações clínicas e complicações como cálculos biliares, colangite e pancreatite aguda. Em cães sua importância clínica ainda é desconhecida. Os objetivos deste estudo foram estimar a prevalência, avaliar fatores de risco, alterações encontradas ao exame de ultrassom e marcadores bioquímicos em cães com lama biliar diagnosticada por ultrassonografia. Determinou-se a prevalência e a influência das diferentes raças, sexo e idade na lama biliar, a partir de 1.021 cães submetidos à ultrassonografia abdominal, independente do estado de saúde. Desse total, foram selecionados por conveniência, 100 cães para avaliação das alterações encontradas na ultrassonografia, dos fatores de risco e dos marcadores bioquímicos perante a presença ou ausência de lama biliar. Os resultados mostraram que a prevalência de lama biliar é alta, sendo que cães com 10 anos ou mais estiveram mais predispostos. Machos e fêmeas foram acometidos em igual intensidade, havendo uma maior prevalência nas raças Beagle, Cocker Spaniel e Poodle. Nenhum dos marcadores bioquímicos estudados demonstrou correlação significativa com a lama e através da quantificação desse sedimento foi possível sugerir que o espessamento biliar raramente progride podendo acarretar complicações mais graves como a mucocele e colelitíase. Condição corporal e a castração não demonstraram relação com a presença de lama biliar e o tipo de dieta não foi considerado como o principal fator de risco, havendo apenas fraca associação da lama com o abuso da alimentação com petiscos veterinários. Já o uso de medicamentos demonstrou estar entre as possíveis causas para o desenvolvimento do espessamento biliar. Pacientes com doenças cardiovasculares encotraram-se no grupo de risco e a maior ocorrência de hepatomegalia nos cães acometidos pela lama foi associada à congestão hepática passiva, consequência das cardiopatias. Acredita-se que o fator idade também possa estar relacionado a esse fato, já que as cardiopatias são mais frequentes em cães mais velhos. / The biliary sludge in dogs is deemed to be an incidental finding, and is often identified during abdominal ultrasound as echogenic sediment of low amplitude without acoustic shadowing and gravity dependent mobility. In humans, the presence of biliary sludge is considered abnormal and it is associated with various medical conditions and complications such as gallstones, cholangitis and acute pancreatitis. In dogs their clinical importance is still unknown. The aims of this study were to estimate prevalence, evaluate risk factors, findings on ultrasound examination and biochemical markers in dogs with biliary sludge diagnosed by ultrasonography. It was determined the prevalence and influence of different breeds, gender and age in biliary sludge, from 1.021 dogs undergoing abdominal ultrasonography, regardless of their health status. Overall, it was selected for convenience, 100 dogs for evaluation of abnormalities found on ultrasound, the risk factors and biochemical markers before the presence or absence of biliary sludge. The results showed that the prevalence of biliary sludge is high, and dogs with 10 years old or more were more predisposed. Males and females were affected at the same intensity, with greater prevalence in breeds Beagle, Cocker Spaniel and Poodle. None of the biochemical markers studied showed a significant correlation with the sludge and through the quantification of sediment was possible to suggest that the thickened bile rarely progresses and may cause more serious complications such as mucocele and cholelithiasis. Body condition and castration showed no correlation with the presence of biliary sludge and the type of diet was not considered a major risk factor, with only a weak association of the sludge with the abuse with veterinarians’ snacks. But the use of medicines proved to be among the possible causes for the development of the thickened bile. Patients with cardiovascular diseases lay in the risk group and higher incidence of hepatomegaly in dogs affected by the mud was associated to passive hepatic congestion, as consequence of cardiopathies. It is believed that the age factor may also be related to this fact, since cardiopathies are more common in older dogs.
|
163 |
Etude in vitro des propriétés probiotiques de bactéries du genre Bacillus : Interaction avec l’hôte et effets de l’association avec un prébiotique / In vitro study of probiotic Bacillus strains : interaction with the host and effect of association with a prébioticVilleger, Romain 12 December 2014 (has links)
Les probiotiques sont des microorganismes vivants qui, lorsqu’ils sont ingérés en quantité adéquate, peuvent exercer des propriétés bénéfiques sur la santé de l’hôte. Les souches de Bacillus utilisées en tant que probiotiques ne sont pas colonisatrices du tractus intestinal, mais sont des résidents transitoires du microbiote. Ce travail fait l’investigation in vitro de l’association, qualifiée de synbiotique, entre une souche probiotique de Bacillus subtilis et une source carbonée prébiotique, composé alimentaire peu digéré par les enzymes intestinales mais utilisable par les bactéries dans l’intestin. L’étude de cette association met en évidence la capacité de la souche à utiliser les isomaltooligosaccharides (IMOS) prébiotiques comme unique substrat carboné. L’effet positif de ce substrat sur la tolérance à la bile de la souche a été démontré in vitro. Les résultats d’une analyse protéomique faisant l’étude des enzymes clés impliquées dans le métabolisme des IMOS, ainsi que d’autres biomarqueurs d’intérêt probiotique, sont en cours d’exploitation. Ce travail préliminaire d’investigation de l’association synbiotique entre les IMOS prébiotiques et la souche probiotique B. subtilis, aboutira à des essais in vivo. Les effets bénéfiques des probiotiques du genre Bacillus, notamment au niveau de la modulation du système immunitaire, résultent de l’interaction entre les molécules de la surface bactérienne et les cellules de l’intestin. Les mécanismes moléculaires à l’origine de l’immunomodulation sont mal connus, alors que leur compréhension est nécessaire à l’optimisation de l’utilisation du probiotique. Un deuxième volet de ce travail concerne la comparaison des structures d’entités moléculaires de surface de trois Bacilli probiotiques, les acides lipotéichoïques (LTAs), et leurs activités immunologiques respectives. Une étude structurale des LTAs par des méthodes biochimiques et par RMN a permis de mettre en évidence la diversité structurale au sein du même genre Bacillus. Le rôle clé de la D-alanine dans l’activité biologique de ces antigènes bactériens a été démontré. / Probiotics are live microorganisms, which when administered in adequate amounts confer a health benefit on the host. Bacillus probiotic strains are not able to colonize the gut, and are considered as transient residents of the microbiota. Prebiotic are non-digestible food ingredients that could stimulate growth of bacteria in the gut. This work investigates the in vitro effect of a prebiotic isomaltooligosaccharide (IMOS) on the growth of a probiotic strain Bacillus subtilis. This study highlights the ability of the strain to use IMOS as unique carbon source. A comparative proteomic analysis investigates the main enzymes implicated in the prebiotic metabolism, and biomarkers possibly involved in probiotic effects. This preliminary work, which studies the synbiotic association between a probiotic and a prebiotic, will lead to in vivo assays. Beneficial effects of probiotic Bacilli, mainly modulation of intestinal immune system, result from interaction between bacterial cell-wall molecules and intestinal cells. The molecular origin of immunomodulatory mechanisms are poorly understood, while understanding is needed to optimize the use of probiotics. A second part of this work consists in comparing the structure of a molecular cell-wall component named lipoteichoic acids (LTA) from three Bacillus probiotic, a molecular cell-wall component of Gram positive bacteria, and their immunological activity. A structural study, using biochemical determinations and NMR spectroscopic analysis, highlights the structural diversity between LTAs from different Bacillus species. The key role of D-alanine substituents in the biological activity of these bacterial antigens has been demonstrated.
|
164 |
Transcriptional Activation of the Cholesterol 7α-Hydroxylase Gene (CYP7A) by Nuclear Hormone ReceptorsCrestani, Maurizio, Sadeghpour, Azita, Stroup, Diane, Galli, Giovanni, Chiang, John Y.L. 01 November 1998 (has links)
The gene encoding cholesterol 7α-hydroxylase (CYP7A), the rate-limiting enzyme in bile acid synthesis, is transcriptionally regulated by bile acids and hormones. Previously, we have identified two bile acid response elements (BARE) in the promoter of the CYP7A gene. The BARE II is located in nt - 149/-118 region and contains three hormone response element (HRE)-like sequences that form two overlapping nuclear receptor binding sites. One is a direct repeat separated by one nucleotide DR1 (-146-TGGACTtAGTTCA-134) and the other is a direct repeat separated by five nucleotides DR5 (-139- AGTTCAaggccGGGTAA-123). Mutagenesis of these HRE sequences resulted in lower transcriptional activity of the CYP7A promoter/reporter genes in transient transfection assay in HepG2 cells. The orphan nuclear receptor, hepatocyte nuclear factor 4 (HNF-4)1, binds to the DR1 sequence as assessed by electrophoretic mobility shift assay, and activates the CYP7A promoter/reporter activity by about 9-fold. Cotransfection of HNF-4 plasmid with another orphan nuclear receptor, chicken ovalbumin upstream promoter- transcription factor II (COUP-TFII), synergistically activated the CYP7A transcription by 80-fold. The DR5 binds the RXR/RAR heterodimer. A hepatocyte nuclear factor-3 (HNF-3) binding site (-175-TGTTTGTTCT-166) was identified. HNF-3 was required for both basal transcriptional activity and stimulation of the rat CYP7A promoter activity by retinoic acid. Combinatorial interactions and binding of these transcription factors to BAREs may modulate the promoter activity and also mediate bile acid repression of CYP7A gene transcription.
|
165 |
A Study of Supramolecular Gels and Self Assembly of Novel Bile Acid ConjugatesRamesh, K January 2013 (has links) (PDF)
Chapter 1: Functional and Responsive Supramolecular Gels
In this chapter ‘supramolecular gels’ derived from small organic molecules with molecular mass of typically less than 2000 daltons are discussed. Representative examples of various low molecular weight gelators based on their natural availability and also divergent functionalities are mentioned (Scheme 1).
Scheme 1
Advances in the recent years have been very rapid in the field of supramolecular chemistry of gels giving rise to ‘Tunable responsive gels’. Control of the gel property in a reversible fashion has been the highlight of responsive gels. A few of the gels which are responsive towards various stimuli such as pH, photoirradiation, cations, anions, neutral species have been discussed.
Advances and scope of supramolecular gels in various applications have also been mentioned in detail with respective examples. Utilities of supramolecular gels in synthesis of nanostructures, in biology and medicine, enzyme recognition, catalysis etc are discussed. (Scheme 2).
Chapter 2: Charge transfer triggered organogels of bis(bile acid)anthracene conjugates and 2,4.7-trinitrofluorenone.
In this chapter the study involves the synthesis of a special class of anthracene based steroidal derivatives. The appending of two amphiphilic bile acid units imparts a unique hydrophobic/ hydrophilic balance on the chromophore. The 2,3-didecyloxyanthracene (DDOA) was reported to be a gelator of various organic solvents but none of the three bile acid derivatives of anthracene synthesized was a gelator on its own. It was also observed that dialkoxy (propyl, heptyl, decyl) derivatives of anthracene formed strong charge-transfer gels in the presence of 2,4,7-trinitrofluorenone (TNF). The addition of electron deficient TNF to the steroidal derivatives of anthracene resulted in the gelation of some specific organic solvents. The driving force behind the gel formation resulted from the charge-transfer (CT) interaction between the electron rich anthracene and electron deficient fluorenone.
Figure 1. Chemical structures of 2,3-bis(bile acid)anthracenes and TNF (centre), a scanning electronic microscopy image of xerogels prepared from bis(deoxycholyl)anthracene and TNF (left) and a photograph of the gel of bis(deoxycholyl)anthracene and TNF in n-octanol.
Thermochromic property (during sol to gel phase transition), absorption and variable temperature fluorescence measurements supported CT interaction. Thermal stability studies and dynamic rheology experiments confirmed that CT gels were thermally most stable and mechanically stronger with equi-molar amounts of the two components. Stiffness values obtained from rheological experiments also suggested that the gels were viscoelastic solids.
Chapter 3(A): Tb(III) sensitization in an organogel matrix: Selective luminescence quenching by an aromatic nitro derivative
In this chapter the discovery of metallo organogel formation by mixing methanolic solutions of Tb(OAc)3 and sodium deoxycholate (NaDCh) has been explored. Sensitization of Tb3+ was observed by doping micromolar quantities of 2,3-dihydroxynaphthalene (DHN). Mechanical properties of Tb3+-DCh gels were investigated by rheology at three different ratios of Tb3+ and DCh. It was observed that increasing in the Tb3+ to DCh ratio increased the mechanical property of the gels. Time delayed emission spectra were recorded with increasing concentration of DHN and luminescence increase was noticed in a linear fashion. Importance of gel matrix was demonstrated by measuring the Tb3+ luminescence at fixed concentration (5 mM) with/without DHN in the solution and gel media.
Figure 2:: Schematic representation of Tb3+ sensitization by DHN. Photograph (right)) of the Tb3++-DCh (5/15 mM) gels with (a) 50 µM DHHN (b) No DHHN under UVV (365 nm).
Sensitization by an electron rich chromophore created interest in us to dope relatively electron deficient compounds into the gel matrix for possible quenching off Tb3+-luminescence. Among the electron deficient analytes screened included 1,5-difluro-2,4-diinitrobenzenne (DFDNB)), 2,4 dinitrophenol (DNPPh), p-nitrobenzaldehydde (p-NB), 2,4,6-trinitrootoluene (TTNT) and 22,4,7¬trinitrofluuorenone (TTNF). Microscopy studies such as AFM, TEMM and SEMM revealed highly entangled fibrous network in the morphology of Tb3+--DCh xerogel. Solid state luminescence experiments suggested that sensiitization was observed in the xerogels and extent of sensitization was comparable to that of the gel state. Xerogel soaking studies inferred the strong adherence of the DHNN to the gel fibres.
Chapter 3(B): Anion dependent structural, morphological and mechanical features of Ln(III)-Cholate gels
In this chapter the counter anion influence on various aspects of hydrogels has been discussed. It has been reported from our laboratory that mixing of aqueous solutions of sodium cholate (15 mM) and various lanthanide acetates (5 mM) followed by sonication resulted in either transparent or transluscent gels. Unsurprisingly we found that aqueous solutions of lanthanide nitrates and lanthanide chlorides also formed hydrogels upon mixing with sodium cholate (Figure 33). Dried films of Tb3++-cholate and Eu3+-cholate gels prepared from their respective nitrate salts displayed birefringent structures under polarizing optical microscopy (POM). But no significant textures of any type were observed in the case of gels prepared from either chloride or acetate salts.
Figure 3:: Photographs of the hydrogels prepared by mixing of aqueous solutions of various salts Tb33+ and Eu3+ with sodium cholate solutions. Scanning electron microscopic images exhibited fibrous structures for all the xerogels in the morphology. Atomic force microscopy and transmission electron microscopy measurements revealed helical morphology for xerogels prepared from nitrate salts where as flat tape-like cross linkage was observed for chloride or acetate based xerogels. Anion effect on mechanical properties was significant in the sense that gels prepared from acetate salts displayed highest mechanical strength followed by nitrate based gels which were stronger than that of chloride based gels. Titration of sodium cholate solution with various lanthanide salt solutions gave the direct evidence of thee pH variation as a function of the anions.
Figure 4: TEM images of xerogels prepared from gels of nitrate salts of Tb3+ (left) and Eu3+ (right)
Chapter 4: Design, synthesis a nd study of bile acid ‘click’ conjugates of perylene bisimides (PBIs) and naphthalene bisimides (NBIs)
In this chapter the synthesis of novel bile acid derivatives of perylene and naphthalene bisimides is discussed. The ‘click’ chemistry procedure was used to link bile acid groups on to the chromophores. Azide derivatives of PBIs and NBIs were prepared inn 3 step methods which were coupled to propargyl esters of bile acids by following standard ‘click chemistry’ protocols to achieve the target molecules (Scheme 3).
Scheme 3
The studies conducted mainly focused on Cholic acid (CA) conjugates of PBIs and NBIs. Steady state absorption and emission studies of CA conjugates were performed in 10% MeOH/DCM system. POM and fluorescence images showed red emissive aggregates in case of PBI films. TEM measurements revealed uniform aggregate sizes for both the films of PBI(CA)2 and NBI(CA)2. SEM and AFM (Fig 5) studies exhibited spherical aggregates of diameter around 100-200 nm for PBI(CA)2 films where as aggregates of diameter around 500-700 nm were observed for NBI(CA)2 films.
Figure 5: AFM images and their corresponding height profiles of PBI films (left) and NBI films (right)
|
166 |
Biomarcadores genotóxicos no monitoramento de estuários com diferentes níveis de contaminação utilizando peixes coletados in situ / Genotoxic biomarkers for monitoring estuarine with different levels of contamination using fish collected in situ.Santos, Patricia Estevam dos 31 July 2009 (has links)
Algumas áreas do canal de Piaçaguera, localizado na Baixada Santista, SP-Brasil, apresenta alto nível contaminação por hidrocarbonetos policíclicos aromáticos (HPA) entre outros contaminantes nos sedimentos. O objetivo do presente estudo foi verificar diferentes biomarcadores de exposição em bile e de efeitos genotóxicos em sangue de peixes, coletados in situ, que poderiam ser utilizados como ferramenta de monitoramento. O canal de Bertioga foi selecionado como região de referência. Embora não seja uma região sem nenhuma interferência de contaminantes, os sedimentos apresentam baixos valores para HPA, metais e atividade mutagênica. A espécie Mugil curema foi selecionada por ser freqüentemente encontrada em ambas as regiões de estudo. Observamos que os peixes coletados no canal de Piaçaguera apresentaram maior porcentagem de micronúcleos e danos ao DNA (ensaio cometa) no sangue quando comparados com a região de referência. Para o teste de micronúcleo, realizamos leituras de 1000 e 4000 células/indivíduo e não foram observadas diferenças estatísticas, sugerindo que o número de 1000 células poderia ser suficiente para gerar dados confiáveis para a espécie Mugil curema. A avaliação de mutagenicidade da bile foi realizada pelo teste Salmonella/microssoma combinado à extração de bile utilizando Blue rayon (BR) com as linhagens TA98, TA100 e YG1041 com e sem S9 (ativação metabólica). As maiores respostas mutagênicas foram observadas para os peixes coletados no canal de Piaçaguera. A mutagenicidade com a linhagem YG1041 na presença de S9 foi mais elevada quando comparado à mutagenicidade observada na ausência de S9 e também em comparação com a sua linhagem parental TA98, indicando a provável presença de compostos da classe das aminas aromáticas na bile como responsáveis pelos efeitos observados. A quantificação de metabólitos equivalentes de HPA foi realizada por HPLC/fluorescência na bile bruta e embora os resultados não se correlacionem com a mutagenicidade, altos níveis também foram encontrados para os peixes coletados no canal de Piaçaguera em comparação com Bertioga. O protocolo de amplificação do gene ras para a espécie Mugil curema foi estabelecido e os genes foram seqüenciados para verificação da presença de mutações. Não foram observadas mutações nos poucos peixes analisados e mais estudos são necessários para verificar a utilização deste biomarcador. O teste de micronúcleo, ensaio cometa e análise de mutagencidade em bile extraída por Blue rayon parecem ser ferramentas biológicas adequadas para monitoramento da qualidade ambiental de estuários contaminados. / Some areas of the Piaçaguera channel at Baixada Santista, SP, Brazil present high levels of polycyclic aromatic hydrocarbons (PAHs) among other contaminants in the sediment. The aim of the present study was to verify if biomarkers of exposure in bile and effect in blood of fishes collected in the field could be used as a monitoring tool. We selected Bertioga channel as a reference area. Although it is not a pristine area, the sediment presents low values of PAHs, metals and mutagenic activity. We selected the fish species Mugil curema, because they are frequently found in both areas during the entire year. We observed that the fish collected at the Piaçaguera channel showed a higher percentage of micronuclei and DNA damage (comet assay) in blood when compared to the Bertioga channel. The micronucleus readings were done in 1000 and 4000 cells/fish and no statistical difference was observed, suggesting that the number of 1000 cells would be sufficient to generate reliable data for the species Mugil curema , in the studied area. The mutagenicity of the bile was performed using the Salmonella/microsome assay combined with Blue rayon (BR) extraction with TA98, TA100 and YG1041 strains with and without rat liver S9. We observed that the mutagenic responses were higher in fish collected in Piaçaguera. The mutagenicity in YG1041 with S9 in fishes collected in the Piaçaguera channel was higher when compared to the mutagenicity observed in the absence of S9 and also higher than the response with the parental strain TA98. The results suggest that mutagenic polycyclic compounds, probably from the class of the aromatic amines are causing the observed effect. PAH metabolites-equivalent were also determined using HPLC/fluorescence in crude bile, and although the results did not correlate with the mutagenicity, higher levels were observed in fish collected in the Piaçaguera channel when compared to Bertioga. A protocol for amplification of the ras gene for the Mugil curema species was established and gene sequenced. No mutations were observed in the liver of the few fishes analyzed, and more studies are required to verify the utility of this biomarker in this fish. The micronuclei, comet assay and mutagenicity in bile extracted with blue rayon seem to be suitable biological tools to monitor the environmental quality of contaminated estuaries.
|
167 |
Estudo termoanalítico e caracterização química de cálculos biliares e bile humana / Thermoanalytical study and chemical characterization of gallstones and human bileMercuri, Lucildes Pita 02 February 2000 (has links)
Este trabalho consiste na caracterização química e termoanalítica da composição química de cálculos biliares e bile humana, coletados da vesícula biliar de pacientes que foram submetidos à colecistectomia no Hospital Universitário da Universidade de São Paulo. As metodologias utilizadas para amostragem, caracterização química e termoanalítica foram previamente otimizadas por um estudo preliminar, trabalhando-se com um total de 38 amostras de cálculos biliares e bile da vesícula biliar humana. A técnica de análise elementar para a determinação dos teores de carbono, hidrogênio e nitrogênio foi usada para a caracterização química junto com a espectroscopia de absorção na região do infravermelho e difração de raios X. Esses resultados foram complementados por dados obtidos pelas técnicas termoanalíticas TG/DTG e DSC. O estudo do comportamento térmico foi realizado empregando as técnicas TG/DTG em atmosfera dinâmica de ar e razão de aquecimento de 10 ºC min-1. No caso da amostra de cálculo biliar SF15, considerada atípica por apresentar um teor de 81% de CaCO3 na sua composição química, utilizou-se atmosfera mista de ar+CO2. Em todos os ensaios foram empregados. Os eventos térmicos (físicos e químicos) foram evidenciados pelas curvas DSC, por picos no sentido endotérmicos e exotérmicos. A comparação dos perfis das curvas TG/DTG e os resultados de perdas de massa evidenciaram junto com os teores de CHN obtidos por análise elementar, possibilitaram classificar os cálculos biliares em oito grupos distintos (A, B, C, D, E, F, G e H). As curvas DSC, os espectros de infravermelho e os difratogramas de raios X, confirmaram a distinção da composição química desses grupos. Deste modo, foi possível a elaboração de uma nova classificação para os cálculos biliares da vesícula biliar humana baseado na sua composição química. / This work consists of the chemical characterization and thermoanalytical of the chemical composition of gallstones and human bile, collected of the gallbladder of patients that were submitted to cholecystectomy at University Hospital of São Paulo University. The methodologies used to sampling, chemical characterization and thermoanalytical were previously optimized for a preliminary study, working with a total of 38 gallstones and human bile samples. For chemical characterization elementary analysis techniques, to carbon, hydrogen and nitrogen determination, infrared spectroscopy and X-rays diffraction were used, these results complemented the obtained thermoanalytical data for TG/DTG and DSC techniques. The gallstones and bile samples thermal behavior study was accomplished using the techniques TG/DTG in dynamic air atmosphere. In the case gallstone SF15 sample, considered like abnormal due to its content of 81% of CaCO3 in its chemical composition. For this one, a mixture air + CO2 was used. In all experiments were used heating rate of 10 °C min-1. The thermal events (physical and chemical) were evidenced by the DSC curves, with endothermic and exothermic peaks. By means of the comparison TG/DTG curves profiles, the results of mass losses for them evidenced, with CHN\'s contents obtained for elementary analysis, they can classify the gallstones in eight distinct groups (A, B, C, D, E, F, G and H). The DSC curves, infrared spectra and X-rays diffraction, they confirmed the chemical composition distinction of these groups. Thus, it was possible the elaboration of a new classification for the gallstones formatted in the human gallbladder based in your chemical composition.
|
168 |
Biomarcadores genotóxicos no monitoramento de estuários com diferentes níveis de contaminação utilizando peixes coletados in situ / Genotoxic biomarkers for monitoring estuarine with different levels of contamination using fish collected in situ.Patricia Estevam dos Santos 31 July 2009 (has links)
Algumas áreas do canal de Piaçaguera, localizado na Baixada Santista, SP-Brasil, apresenta alto nível contaminação por hidrocarbonetos policíclicos aromáticos (HPA) entre outros contaminantes nos sedimentos. O objetivo do presente estudo foi verificar diferentes biomarcadores de exposição em bile e de efeitos genotóxicos em sangue de peixes, coletados in situ, que poderiam ser utilizados como ferramenta de monitoramento. O canal de Bertioga foi selecionado como região de referência. Embora não seja uma região sem nenhuma interferência de contaminantes, os sedimentos apresentam baixos valores para HPA, metais e atividade mutagênica. A espécie Mugil curema foi selecionada por ser freqüentemente encontrada em ambas as regiões de estudo. Observamos que os peixes coletados no canal de Piaçaguera apresentaram maior porcentagem de micronúcleos e danos ao DNA (ensaio cometa) no sangue quando comparados com a região de referência. Para o teste de micronúcleo, realizamos leituras de 1000 e 4000 células/indivíduo e não foram observadas diferenças estatísticas, sugerindo que o número de 1000 células poderia ser suficiente para gerar dados confiáveis para a espécie Mugil curema. A avaliação de mutagenicidade da bile foi realizada pelo teste Salmonella/microssoma combinado à extração de bile utilizando Blue rayon (BR) com as linhagens TA98, TA100 e YG1041 com e sem S9 (ativação metabólica). As maiores respostas mutagênicas foram observadas para os peixes coletados no canal de Piaçaguera. A mutagenicidade com a linhagem YG1041 na presença de S9 foi mais elevada quando comparado à mutagenicidade observada na ausência de S9 e também em comparação com a sua linhagem parental TA98, indicando a provável presença de compostos da classe das aminas aromáticas na bile como responsáveis pelos efeitos observados. A quantificação de metabólitos equivalentes de HPA foi realizada por HPLC/fluorescência na bile bruta e embora os resultados não se correlacionem com a mutagenicidade, altos níveis também foram encontrados para os peixes coletados no canal de Piaçaguera em comparação com Bertioga. O protocolo de amplificação do gene ras para a espécie Mugil curema foi estabelecido e os genes foram seqüenciados para verificação da presença de mutações. Não foram observadas mutações nos poucos peixes analisados e mais estudos são necessários para verificar a utilização deste biomarcador. O teste de micronúcleo, ensaio cometa e análise de mutagencidade em bile extraída por Blue rayon parecem ser ferramentas biológicas adequadas para monitoramento da qualidade ambiental de estuários contaminados. / Some areas of the Piaçaguera channel at Baixada Santista, SP, Brazil present high levels of polycyclic aromatic hydrocarbons (PAHs) among other contaminants in the sediment. The aim of the present study was to verify if biomarkers of exposure in bile and effect in blood of fishes collected in the field could be used as a monitoring tool. We selected Bertioga channel as a reference area. Although it is not a pristine area, the sediment presents low values of PAHs, metals and mutagenic activity. We selected the fish species Mugil curema, because they are frequently found in both areas during the entire year. We observed that the fish collected at the Piaçaguera channel showed a higher percentage of micronuclei and DNA damage (comet assay) in blood when compared to the Bertioga channel. The micronucleus readings were done in 1000 and 4000 cells/fish and no statistical difference was observed, suggesting that the number of 1000 cells would be sufficient to generate reliable data for the species Mugil curema , in the studied area. The mutagenicity of the bile was performed using the Salmonella/microsome assay combined with Blue rayon (BR) extraction with TA98, TA100 and YG1041 strains with and without rat liver S9. We observed that the mutagenic responses were higher in fish collected in Piaçaguera. The mutagenicity in YG1041 with S9 in fishes collected in the Piaçaguera channel was higher when compared to the mutagenicity observed in the absence of S9 and also higher than the response with the parental strain TA98. The results suggest that mutagenic polycyclic compounds, probably from the class of the aromatic amines are causing the observed effect. PAH metabolites-equivalent were also determined using HPLC/fluorescence in crude bile, and although the results did not correlate with the mutagenicity, higher levels were observed in fish collected in the Piaçaguera channel when compared to Bertioga. A protocol for amplification of the ras gene for the Mugil curema species was established and gene sequenced. No mutations were observed in the liver of the few fishes analyzed, and more studies are required to verify the utility of this biomarker in this fish. The micronuclei, comet assay and mutagenicity in bile extracted with blue rayon seem to be suitable biological tools to monitor the environmental quality of contaminated estuaries.
|
169 |
Efeito do tamoxifeno na fibrose, colágeno e expressão do transforming growth factor -B1, -B2 e -B3 na anastomose da via biliar principal deporcosSiqueira, Orlando Hiroshi Kiono January 2017 (has links)
Submitted by Verônica Esteves (vevenesteves@gmail.com) on 2018-01-11T14:41:24Z
No. of bitstreams: 2
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Tese Orlando Siqueira.pdf: 2924925 bytes, checksum: c32bce21e6c777f33da53c373787cb05 (MD5) / Approved for entry into archive by Verônica Esteves (vevenesteves@gmail.com) on 2018-01-11T14:41:40Z (GMT) No. of bitstreams: 2
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Tese Orlando Siqueira.pdf: 2924925 bytes, checksum: c32bce21e6c777f33da53c373787cb05 (MD5) / Made available in DSpace on 2018-01-11T14:41:40Z (GMT). No. of bitstreams: 2
license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Tese Orlando Siqueira.pdf: 2924925 bytes, checksum: c32bce21e6c777f33da53c373787cb05 (MD5)
Previous issue date: 2017 / Universidade Federal Fluminense. Hospital Universitário Antônio Pdro / Introdução: A anastomose término-terminal no tratamento da lesão das vias biliares durante a colecistectomia laparoscópica tem sido associada à formação de estenose. O objetivo deste estudo foi investigar experimentalmente o efeito do tratamento oral com tamoxifeno (tmx) sobre a fibrose, o colágeno e o transforming growth factor TGF-β1, - β2 e - β3 na anastomose da via biliar principal de porcos. Métodos: Vinte e seis porcos foram divididos em três grupos [sham (n = 8), controle (n = 9) e tmx (n = 9)]. Os ductos biliares foram seccionados e anastomosados nos grupos controle e tmx. Tmx (40 mg / dia) foi administrado oralmente ao grupo tmx, e os animais foram eutanasiados após 60 dias. A fibrose foi analisada pela coloração com tricromo de Masson. Picrosirius red foi utilizado para quantificar o teor total de colágeno e a proporção de colágeno tipo I / III. A expressão de mRNA do TGF-β1, -β2 e - β3 foi quantificada usando a reação em cadeia da polimerase em tempo real (qRT-PCR). Resultados: Os grupos de controle e estudo apresentaram fibrose maior do que o grupo sham, e o grupo de estudo apresentou fibrose menor do que o grupo controle (p = 0,011). Os grupos controle e tmx apresentaram maior teor total de colágeno do que o grupo sham (p = 0,003) e não houve diferença significativa entre os grupos controle e tmx. A proporção de colágeno tipo I / III foi maior no grupo controle do que nos grupos sham e tmx (p = 0,015) e não houve diferença significativa entre os grupos sham e tmx. Não houve diferenças significativas na expressão de mRNA de TGF-β1, -β2 e -β3 entre os grupos (p> 0,05).
Conclusões: Tmx diminuiu a fibrose e impediu a alteração na proporção de colágeno tipo I / III causada pelo procedimento. / Introduction: End-to-end anastomosis in the treatment of bile duct injury during laparoscopic cholecystectomy has been associated with the formation of stenosis. The aim of this study was to experimentally investigate the effect of oral treatment with tamoxifen (tmx) on fibrosis, collagen and transforming growth factor TGF-β1, - β2 and – β3 on anastomosis of the common bile duct in pigs. Methods: Twenty-six pigs were divided into three groups (sham (n = 8), control (n = 9) and tmx (n = 9)). The bile ducts were sectioned and anastomosed in the control and tmx groups. Tmx (40 mg / day) was administered orally to the tmx group, and the animals were euthanized after 60 days. Fibrosis was analyzed by Masson's trichrome staining. Picrosirius red was used to quantify the total collagen content and the proportion of collagen type I / III. Expression of TGF-β1, -β2 and -β3 mRNA was quantified using the real-time polymerase chain reaction (qRT-PCR). Results: The control and study groups presented higher fibrosis than the sham group, and the study group had lower fibrosis than the control group (p = 0.011). The control and tmx groups presented higher total collagen content than the sham group (p = 0.003) and there was no significant difference between the control and tmx groups. The proportion of type I / III collagen was higher in the control group than in the sham and tmx groups (p = 0.015) and there was no significant difference between the sham and tmx groups. There were no significant differences in TGF-β1, -β2 and -β3 mRNA expression between the groups (p> 0.05). Conclusions: Tmx decreased fibrosis and prevented the change in the proportion of collagen type I / III caused by the procedure.
|
170 |
Le marquage des peptides avec des métaux et détection par MS et l'optimisation des procédures de l'extraction de métalloprotéin dans les échantillons biologiques à des fins de protéomique / Peptide labeling with metals using MS detection and optimization of metalloprotein extraction procedures in biological samples with proteomic purposesLyrio Tenorio Correia, Carolina 10 March 2014 (has links)
Ce travail a développé une nouvelle méthode pour l'identification et la quantification des peptides, par l'optimisation de certaines stratégies disponibles appropriées pour le marquage des peptides avec des métaux lanthanide, une séparation par nano-HPLC et détection UV, et suivi par MALDI MS. Tout d'abord, les peptides ont été marqués avec les trois métaux lanthanides différents et un réactif fonctionnel - DOTA. Les résultats montrent que la réaction de transformation en dérivé à l'aide du réactif chélateur DOTA-NHS-ester a été efficace pour des peptides individuels et des mélanges de peptides, vérifiées à partir de la relation m/z obtenue par MALDI MS. L'application optimisée d’un complexe (Cytochrome C digest) a montré des résultats comparables à ceux obtenus avec des peptides modèles. En parallèle, nous avons effectué l’optimisation pour la purification de métalloprotéine dans la bile de poisson, qui est signalée entant que biomarqueurs de contamination métallique de l'environnement. Des procédures différentes (différents moments de centrifugation et différentes températures de traitement thermique) et les agents (DTT, β-mercaptoéthanol et TCEP) réduisant ont été apliqués pour purifier les MT isolées de la bile et du foie des poissons (Oreochromis niloticus). Des analyses spectrophotométriques ont été utilisées pour quantifier les échantillons de MT, et le gel SDS-PAGE a été utilisé pour évaluer qualitativement les différents résultats de la procédure. Chaque procédure a en suíte été évaluée statistiquement, une méhtode des surfaces de réponse a été appliquée. Les MT de la bile semblent être plus adéquate pour la surveillance de l'environnement en ce qui concerne l'exposition récente à des xénobiotiques qui peuvent influer sur l'expression protéomique et metalloproteomique de cette matrice biologique. Une procédure d’exposition à des métaux dans le laboratoire a montré que les métaux étaient significativement importante pour l’évaluation de la contamination à partir de la quantification de MT, selon le traitement de données par une techinique de réseau neural. / This work developed a new method for the identification and quantification of peptides, by optimizing some of the available strategies suitable for labeling peptides with lanthanide metals with subsequent separation by nano-HPLC with UV detection, matrix-assisted laser desorption ionization-mass spectrometry (MALDI MS). First, peptides were labeled with the three different lanthanide metals using a functional DOTA-based reagent. The results demonstrate that the derivatization reaction using the chelating reagent DOTA-NHS-ester was effective for single peptides and peptide mixtures, verified from the m/z relation obtained by MALDI MS. The application of the optimized method in a more complex matrix (Cytochrome C digest) showed results comparable to those obtained with model peptides. In parallel, environmental analyses were conducted, by performing the standardization of metalloprotein purification in fish bile, since this matrix has been reported as a biomarker for environmental metal contamination. Different procedures (varying centrifugation times and heat-treatment temperatures) and reducing agents (DTT, β-mercaptoethanol and TCEP) were applied to purify MT isolated from fish (Oreochromis niloticus) bile and liver. Spectrophotometrical analyses were used to quantify the resulting MT samples, and SDS-PAGE gels were used to qualitatively assess the different procedure results. Each procedure was then statistically evaluated. A response surface methodology was applied for bile samples, in order to further evaluate the responses for this matrix. In an environmental context, biliary MT was lower than liver MT, and, bile MT seems to be more adequate in environmental monitoring scopes regarding recent exposure to xenobiotics that may affect the proteomic and metalloproteomic expression of this biological matrix. A procedure for exposure to metals in the laboratory showed that some metals are significantly important for the assessment of contamination from the quantification of MT, according to the data processing by atifical neural network (ANN).
|
Page generated in 0.0458 seconds