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Eficàcia dels tocotrienols com a estratègia de tractament de la fibrosi intestinalLuna Cornadó, Jeroni 31 October 2011 (has links)
En el patró fibroestenosant de la malaltia de Crohn els fibroblasts intestinals augmenten en número contribuint al desenvolupament de la fibrosi. Un dels principals promotors de la proliferació d’aquestes cèl•lules és el bFGF. En el present estudi la fracció rica en tocotrienol ha demostrat tenir efectes antiproliferatius en fibroblasts intestinals humans independentment de la procedència dels fibroblasts. Els tocotrienols redueixen tant la proliferació basal com la induïda per bFGF en fibroblasts.
L’apoptosi de les cèl•lules efectores en el desenvolupament de la fibrosi sembla ser el principal mecanisme de la seva resolució. Els tocotrienols instauraren un procés complert d’apoptosi en els fibroblasts. A diferència del que passa amb la majoria d’agents proapoptòtics, els tocotrienols provoquen l’activació tant de la via extrínseca com de la via intrínseca de l’apoptosi ja que activa les caspases 8 i 9.
Sorprenentment, l’addició de ciclosporina A (CsA), un conegut inhibidor de la via intrínseca de l’apoptosi, bloqueja completament el procés d’apoptosi induït per FRT. Això demostra que tot i l’activació de la caspasa 8 i per tant, de la via extrínseca, en el tractament amb tocotrienols la predominant és la via intrínseca.
L’autofàgia té un paper molt rellevant en l’aclariment de cossos apoptòtics. Els tocotrienols han demostrat eficàcia en la inducció d’autofàgia en fibroblasts, ja que provoca la maduració de la proteïna LC3 i l’aparició de vacuoles autofàgiques en el citoplasma d’aquestes cèl•lules. Un cop més la CsA reverteix aquest procés, i per tant inhibeix l’autofàgia, demostrant que aquest procés requereix la participació de la mitocòndria.
Les patologies que cursen amb desenvolupament de fibrosi estan associades a alts nivells de TGF-β que resulta en el reclutament de fibroblasts al lloc de la lesió i a un increment en la producció de matriu extracel•lular. A nivell intracel•lular, la fosforilació d’Smad3 és el pas clau que regula les accions del TGF-β. Els tocotrienols han mostrat eficàcia en la disminució dels nivells intracel•lulars d’Smad3 fosforilada induïda per TGF-β.
La fosforilació d’Smad3 té efectes oposats en la regulació de l’expressió gènica. Regula positivament l’expressió de TIMP-1, en canvi, regula negativament l’expressió de MMP-3. Tot i ser efectes oposats en quant a expressió gènica, aquests dos fenòmens afavoreixen l’acumulació de matriu extracel•lular. L’exposició a tocotrienols fa que es reverteixi aquest estat profibrogènic ja que indueix l’expressió de MMP-3 però no afecta als nivells de TIMP-1.
La síntesi de MEC i especialment la síntesi de COL1, COL3 i COL5 està incrementada en la fibrosi intestinal, aquest fet està directament relacionat amb l’activitat de TGF-β en la zona afectada. Els tocotrienols interfereixen en la síntesi de col•lagen.
A més, els tocotrienols disminueixen la fosforilació d’Smad3 induïda per TGF-β, un fet clau en la síntesi de matriu extracel•lular.
Aquests resultats permeten hipotetitzar un potencial antifibrogènic dels tocotrienols. Per a confirmar aquest potencial “in vivo” ens calia disposar d’un model experimental de fibrosi intestinal. A diferència del que succeeix amb la colitis, en la que es disposa d’un gran nombre de models animals, hi ha pocs models experimentals específicament dissenyats per a reproduir la fibrosi intestinal. Aquest fet, ha limitat molt el desenvolupament de noves estratègies de tractament antifibrogènic en l’intestí.
Mitjançant l’administració intracolònica repetida a dosis baixes de l’haptè TNBS vam poder establir fibrosi intestinal en la rata de manera rellevant i reproduïble.
En aquest model de fibrosi intestinal, els animals que van rebre la dosi més alta de tocotrienols provada en aquest estudi van mostrar nivells disminuïts en paràmetres que mesuren la inflamació, això és, es va disminuir l’índex d’activitat de la malaltia i la pèrdua de pes causada pel TNBS així com també va reduir l’expressió de TNF-α. / Excessive fibroblast expansion and extracellular matrix deposition are key events for the development of bowel stenosis in Crohn’s disease patients. Tocotrienols are vitamin E compounds with proven in vitro antifibrogenic effects on rat pancreatic fibroblasts. We aimed at investigating the effects of tocotrienols on human intestinal fibroblast proliferation, apoptosis, autophagy, and synthesis of ECM.
Intestinal fibroblasts isolated from patients with Crohn’s disease were treated with tocotrienol-rich fraction from palm oil.
Tocotrienols significantly reduced proliferation, enhanced cell death by promoting apoptosis and autophagy. Fibroblast apoptosis, but not autophagy, was prevented by the pan-caspase inhibitor zVAD-fmk, whereas both types of cell death were prevented when the mitochondrial permeability transition pore was blocked by cyclosporin A, demonstrating a key role of the mitochondria in these processes. TRF diminished procollagen type I and laminin γ production these cells.
Transforming growth factor-β plays a key role in matrix deposition during fibrosis. Treatment of intestinal fibroblasts with tocotrienol rich fraction prevents Smad3 phosporylation induced by transforming growth factor-β and reduces collagen type 1 and 3 production by these cells.
Besides, in a rat model of intestinal fibrosis, treatment with tocotrienols reduces diarrhea, rectal bleeding and weight loss, as well as levels of colonic tumor necrosis factor-α and vimentin expression demonstrating that this compound has anti-inflammatory effects in vivo.
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Gating of cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels by nucleoside triphosphatesZeltwanger, Shawn January 1998 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / Typescript. Vita. Includes bibliographical references (l. 140-148). Also available on the Internet.
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Incidenicia da fibrose cistica calculada atraves de portadores do alelo ?F508 no Nordeste e Sudeste do Brasil / Cystic fibrosis incidence calculated from heterozygote frequencies in Northeast and Southeast BrazilArruda, Leonardo Vicentini 14 August 2007 (has links)
Orientador: Carmen Silvia Bertuzzo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-09T09:38:13Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: A incidência da fibrose cística no Brasil é significativamente variável, com diferenças de até 20 vezes de acordo com o grupo étnico e região geográfica estudada. A população brasileira é composta da mistura de muitos grupos étnicos. Os portugueses começaram a colonização no século XVI. Os holandeses invadiram o nordeste em 1630. Os africanos foram trazidos ao Brasil, numa contínua migração forçada, que perdurou do século XVI ao século XIX. No final do século XIX, tiveram início novos movimentos migratórios, principalmente da Alemanha, Itália, Arábia e Espanha. Durante as três primeiras décadas do século XX, nova corrente migratória ocorreu, principalmente da Itália, Espanha e Portugal Após a segunda guerra mundial, o Brasil recebeu novos imigrantes (japoneses, judeus) compondo esta população. Este estudo gerou os primeiros dados sobre a incidência da FC no nordeste e também foram obtidos novos dados para a região sudeste. Na época do estudo, na cidade de Campinas estão sob atendimento no ambulatório 70 pacientes não aparentados com dois testes de suor alterados. Nestes pacientes, foram triadas as seguintes mutações. ?F508 (50%), G542X (4,29%), R1162X (2,14%), N1303K (1,43%) e R553X (0,71%). A mutação G551D não foi encontrada. A mutação ?F508 também foi analisada em 1.138 mulheres saudáveis, sendo 694 da cidade de Campinas - SP e 444 de João Pessoa ¿ PB com idade média de 26,3 anos (15-39, ±6,8), que participaram voluntariamente de projeto de pesquisa anterior. Nas amostras coletadas em Campinas n=694 não foi encontrado nenhum alelo mutante 0/1.388, o que nos impediu de calcular a incidência nesta cidade através deste método. Dos 888 alelos analisados de João Pessoa, foram encontrados quatro alelos mutantes (p=0,0045). Sabendo que a mutação ?F508 corresponde a aproximadamente 50% dos alelos de indivíduos com FC no Brasil, a freqüência dos alelos causadores da FC foi estimada utilizando a proporção: (0,0045/0,5)=0,0090. Com isso, para a cidade de João Pessoa a incidência estimada desta doença autossômica recessiva é de 1:12.321 indivíduos. Esta incidência é similar à encontrada por afro-brasileiros, entretanto difere por exemplo, da encontrada na população do RS. Quando utilizamos o método de cruzamento de dados étnicos das duas regiões estudadas com dados literários da doença nos diferentes grupos étnicos, na cidade de Campinas a incidência da FC ficaria em 1/4.434 e na cidade de João Pessoa ficaria 1/6.087 / Abstract: The incidence of the Cystic Fibrosis (CF) is significantly variable in Brazil, with differences larger than 20 fold, according with the ethnic group and geographic studied region. Brazilian population is composed by ethnic admixture. Portuguese started colonization in the 16th century. The Netherlander invaded the northeast in 1630. The Africans were brought to Brazil, in a continuous forced migration, which lasted from 16th to 19th centuries. In the 19th century, new migratory movements have begun from Germany, Italy, Arab and Spain. In the first three decades of the 20th century, started a new migratory flow, mainly from Italy, Spain and Portugal. After the World War II, Brazil received additional immigrants (Japanese, Jewish) compounding its population. These studies generated the first data about the CF incidence on the Brazilian northeast and also were obtained new data about the southeast region. At the time of this study, 70 non related patients were attended at the local CF center in Campinas, with two positive sweat tests in the city of Campinas-SP. On theses patients were screened the following mutations: ?F508 (50%), G542X (4.29%), R1162X (2.14%), N1303K (1.43%) and R553X (0.71%). The mutation G551D wasn¿t found. The ?F508 mutation was also analyzed in 1,138 healthy voluntary women, 694 from Campinas ¿ SP and 444 from João Pessoa ¿ PB, with average age of 26.3 years (15-39, ±6.8), who previously participated from another research. In the samples collected in Campinas ¿ SP n=694 wasn¿t found any mutated allele 0/1,388 and so, we wasn¿t able to make any incidence calculation through this method. In the 888 alleles from João Pessoa, four carry the ?F508 mutation (p=0.0045). Knowing that this mutation accounts for approximately 50% of the FC patients alleles in Brazil, the incidence of the CF in this region was estimated using the proportion: (0.0045/0.5)=0.009. Thus, the estimated incidence of this recessive disease in João Pessoa was 1:12,321. This incidence is similar to the found in African-Brazilians, although differs for example, to the found on the RS population. When we use the method of crossing ethnic data of both studied regions with literary data of the disease in the different ethnic groups, in the city of Campinas, the incidence of the CF would be in 1/4,434 and in the city of João Pessoa would be 1/6,087 / Mestrado / Mestre em Farmacologia
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Freqüência de polimorfismos do gene CFTR em pacientes portadores de pancreatite crônica alcoólica / Polymorphisms in patients with alcoholic chronic pancreatitisMarianges Zadrozny Gouvêa da Costa 19 March 2008 (has links)
A dependência de álcool acomete de 10 a 12% da população mundial, estando a associação entre uso abusivo do álcool e pancreatite crônica bem estabelecida. A suscetibilidade pancreática ao álcool é variável e apenas 5 a 10% dos etilistas crônicos desenvolvem pancreatite crônica, sendo o papel dos fatores genéticos neste processo praticamente desconhecido. O gene CFTR (cystic fibrosis transmenbrane conductance regulator) codifica proteína que funciona na membrana plasmática de células epiteliais e que tem papel chave na função pancreática exócrina normal, promovendo a regulação, da secreção de fluídos e bicarbonato, importantes para a diluição e a alcalinização do suco pancreático. Quando a função desta proteína é inadequada, observa-se obstrução de pequenos ductos por rolhas protéicas. Várias pesquisas buscam documentar a associação fibrose cística - pancreatite crônica, porém os resultados são conflitantes. Este trabalho pesquisou a freqüência de polimorfismos no trato de politiminas e poli TGs no intron 8 do gene CFTR em pacientes portadores de pancreatite crônica alcoólica. Foram estudados três grupos de pacientes: Grupo A - adultos alcoolistas com diagnóstico de pancreatite crônica; Grupo B - adultos alcoolistas sem pancreatopatia ou cirrose hepática e Grupo C - adultos sadios não alcoolistas. O DNA genômico para análise do gene CFTR foi extraído do sangue periférico, pesquisando-se a freqüência de polimorfismos no trato de politiminas e poli TGs no intron 8. O genótipo 5T/7T foi mais encontrado no grupo A do que no B (p = 0,0481), não havendo diferença quando comparados os grupos A e C (p = 0,1317). Pacientes com pancreatite crônica por álcool com o genótipo 5T/7T tiveram menor incidência de diabetes melito do que aqueles com outros genótipos (p = 0,0465). A combinação de haplótipos 10TG 7T / 11TG 7T foi mais freqüente nos grupos B e C do que no A e poderia, eventualmente, ser um fator protetor contra o desenvolvimento da pancreatite crônica. (p = 0,0080 e 0,0162). Em conclusão, há diferenças no intron 8 do gene CFTR em pacientes com pancreatite crônica alcoólica, quando comparados com alcoolistas não pancreatopatas e indivíduos com o genótipo 5T/7T teriam maior risco de desenvolver pancreatite crônica quando se tornam alcoolistas crônicos. / The alcohol dependence affects from 10 to 12% of the world-wide population, being the association between alcohol abuse and chronic pancreatitis well established. The pancreatic susceptibility to the alcohol is only 5 to 10%, being the paper of the genetic factors practically unknown. The CFTR gene (cystic fibrosis transmenbrane conductance regulator) codifies a protein that functions in the epithelial cells and has a role in pancreatic exocrine function, promoting regulation of the secretion of fluids and bicarbonate, important for the dilution and the alcalinization of the pancreatic juice. When the function of this protein is inadequate, blockage of small ducts occurs. Some research regist the association cystic fibrosis - chronic pancreatite, however the results are conflicting. This work searched the frequency of polymorphisms in the polyT and poly TGs tracts in intron 8 of CFTR gene in patients with alcoholic chronic pancreatitis. Three groups of patients have been studied: Group A - adult alcoholics with chronic pancreatitis; Group B - adult alcoholics without pancreatic disease or hepatic cirrhosis and Group C - non alcoholics healthy adults. DNA analysis of CFTR gene was made after extraction from peripheral blood samples. The 5T/7T genotype was more frequently found in group A that in B (p = 0.0481), with no difference when compared to group C (p = 0,1317). Patients with alcoholic chronic pancreatitis and 5T/7T genotype had less incidence of diabetes mellitus that those with other genotypes (p = 0,0465). The haplotype combination 10TG 7T / 11TG 7T was more frequent in groups B and C that in A and it could, eventually, be a protective factor against the development of alcoholic chronic pancreatitis. (p = 0,0080 and 0,0162). In conclusion, we found differences when these tree groups are compared and individuals with 5T/7T genotype would have greater risk to develop chronic pancreatitis if they become alcoholics.
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Fibrose cística = avaliação diagnóstica através da diferença de potencial nasal e sua correlação com duas mutações genéticas / Cystic fibrosis diagnostic evaluation through nasal potential difference and its correlation with two genetic mutationsNg, Ronny Tah Yen, 1979- 23 August 2018 (has links)
Orientador: Eulalia Sakano / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-23T20:48:54Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: A fibrose cística (FC) é uma doença genética autossômica recessiva, resultante da ausência total na proteína CFTR (Cystic Fibrosis Transmembrane Conductance Regulator), ou de alterações qualitativas ou quantitativas do gene que transcreve esta proteína, em células de diversos órgãos do corpo humano, resultando em inúmeros genótipos e fenótipos desta doença. Em muitos pacientes, o diagnóstico é difícil de ser definido, pelo método clássico de dosagem de sódio e cloro no suor, ou pelo sequenciamento genético, justificando a utilização de novas técnicas de auxílio diagnóstico, como a Diferença de Potencial Nasal (DPN). Este teste proporciona uma forma de avaliação direta e sensível, através do epitélio nasal, do transporte de sódio e cloro das membranas celulares, baseado nas propriedades bioelétricas transepiteliais. O objetivo deste trabalho foi verificar se existe diferença dos valores obtidos no exame de DPN em pacientes com FC em comparação com indivíduos controles saudáveis; e verificar se este teste permite diferenciar pacientes com FC das subclasses funcionais mais graves (I, II, III) das subclasses menos graves (IV, V, VI). Foram incluídos no estudo 15 pacientes FC, 10 com mutações mais graves (grupo A) e 5 com mutações menos graves (grupo B), e 21 controles saudáveis (grupo C). Foram considerados os seguintes parâmetros do teste da DPN: "Finger", PDMax, ?Amilorideo, ?Amilorídeo+livrecloreto e index de Wilchanski. Para a variável "Finger", foi encontrada diferença entre pacientes com FC grupo B - mutações menos graves (classe IV, V ou VI) e indivíduos saudáveis - grupo C. O valor do index de Wilchanski mostrou diferença entre pacientes com FC grupo A - mutações mais graves (classes I, II ou III) e indivíduos saudáveis - grupo C. No nosso estudo, a DPN mostrou valores estatisticamente diferentes entre FC com 2 mutações conhecidas e sujeitos saudáveis. Porém, não conseguiu diferenciar fibrocísticos com mutações mais graves (classes I, II e III) daqueles com mutações consideradas menos graves (classes IV, V e VI) / Abstract: Cystic fibrosis (CF) is an autosomal recessive genetic disease, due to the total absence of protein CFTR (Cystic Fibrosis Transmembrane Conductance Regulator), or due to qualitative or quantitative changes in the gene that transcript this protein in cells of various organs of the human body, resulting in numerous genotypes and phenotypes of the disease. In several patients, the diagnosis is difficult to be defined by the classical method of sodium and chloride dosage in sweat, or by genetic sequencing, justifying the use of new techniques for diagnosis, as the Nasal Potential Difference (NPD). This test provides a way of direct and sensitive assessment of the transport of sodium and chloride ions in cell membranes, via the nasal epithelium, based on transepithelial bioelectric properties. The objective of this work was to verify the difference of the values obtained in the examination of NPD in patients with CF compared with healthy control subjects, and, to verify if this test allows differentiating patients with more severe CF functional subclasses (I, II , III) from patients with less severe CF subclasses (IV, V, VI). This study included 15 CF patients, 10 with more severe mutations (group A) and 5 with less severe mutations (group B), and 21 healthy controls (group C). We considered the following test parameters of NPD: "Finger", PDMax, ?Amiloride, ?Amiloríde+Chloridefree and Wilchanski index. For "Finger" values, it was found difference between patients with CF Group B - less severe mutations (class IV , V or VI) and healthy individuals - group C. The value of Wilchanski index showed difference between group A CF patients, with more severe mutations (class I, II or III) and healthy individuals - group C. In our study, NPD showed statistically different values between CF patients with two known mutations and healthy subjects. However, it was not able to distinguish between CF patients with more severe mutations (class I, II and III) of the CF patientswith less severe mutations (Class IV, V and VI) / Mestrado / Otorrinolaringologia / Mestre em Ciências Médicas
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Rôle des complexes de gadolinium dans le mécanisme de la fibrose systémique néphrogénique / Role of gadolinium complexes in the mechanism of nephrogenic systemic fibrosisFretellier, Nathalie 19 June 2013 (has links)
La fibrose systémique néphrogénique (FSN) est une maladie rare et relativement récente, observée uniquement chez des patients souffrant d’insuffisance rénale sévère ou terminale. Elle est liée à l’administration d’une certaine catégorie de complexes de gadolinium (CG), les CGs thermodynamiquement moins stables, utilisés comme produits de contraste pour l’imagerie par résonance magnétique. L’hypothèse mécanistique la plus couramment citée concerne les effets profibrosants du Gd3+ « libre » après dissociation in vivo des CGs les moins stables mais il n’en existe pas de démonstration formelle. La physiopathologie de cette maladie reste mal connue, notamment par manque de modèles précliniques pertinents. Les travaux de cette thèse répondent donc à la nécessité d’approfondir nos connaissances concernant les relations entre les propriétés physicochimiques des CGs (structure, stabilité) et le risque de toxicité chronique, afin de mieux comprendre leur rôle dans le mécanisme de la FSN. Nous avons mis aux points plusieurs modèles de FSN chez le Rat. Nous avons aussi comparé les effets de toutes les catégories structurales des CGs sur ces modèles. Une toxicité systémique importante et la survenue de lésions cutanées macroscopiques et d’une fibrose du derme sont notées après administration de gadodiamide (un CG linéaire et ionique de faible stabilité), ce qui est cohérent avec le fait que la grande majorité des cas de FSN sont associés à cet agent. Nous avons aussi montré que cette toxicité dépend du degré d’insuffisance rénale et que l’hyperphosphatémie sensibilise les animaux aux effets profibrosants du gadodiamide. Nos données suggèrent donc que ces facteurs associés sont des facteurs de risque de la FSN. Nous avons observé la dissociation progressive in vivo de deux CGs linéaires présentant une faible stabilité, le gadodiamide et l’acide gadopentétique, après administration chez le Rat insuffisant rénal, avec libération de Gd3+ sous forme libre et soluble. Les CGs macrocycliques sont restés stables. Nous avons confirmé cette stabilité sur du sérum de Rat et du sérum humain alors que le gadodiamide se dissocie in vitro. Nos données suggèrent aussi une interaction entre l’ion Gd3+ dissocié à partir du gadodiamide et les protéines sériques. Cette libération de Gd3+ est accélérée en présence d’une forte concentration de phosphate. Globalement, nos résultats suggèrent ainsi un rôle causal du Gd3+ libre dans les lésions cutanées observées chez les animaux insuffisants rénaux. Enfin, nous avons observé l’implication de la voie de signalisation canonique de TGFβ, le marqueur clé de la fibrose, uniquement chez des rats ayant reçu le gadodiamide et dont l’insuffisance rénale est modérée. Nos travaux sont donc en faveur de l’hypothèse mécanistique d’une dissociation des CGs peu stables. / Nephrogenic systemic fibrosis (NSF) is a rare systemic fibrosing disorder which has been described in patients with severe or end stage renal failure. NSF is associated with prior administration of certain gadolinium complexes (GCs), used as magnetic resonance imaging contrast agents, particularly those which have the lowest thermodynamic stability. The most widely accepted hypothesis regarding the mechanism is based on profibrotic effects of free Gd3+ following in vivo dissociation of the less stable GCs. Nevertheless, there is no conclusive evidence so far. The pathophysiology is not completely understood, especially due to the lack of relevant non-clinical models. The purpose of our thesis was to investigate the relationship between physicochemical properties of GCs (molecular structure, thermodynamic stability) and the risk of chronic toxicity (especially fibrosis), in order to enhance our understanding of their role in the mechanism of NSF. We have set-up various non-clinical models of NSF in renally-impaired rats. We also compared the effects of all categories of GCs on these models. A high systemic toxicity, associated with macroscopic skin lesions and dermal fibrosis, was observed after the administration of gadodiamide (a linear and nonionic GC with a low thermodynamic stability). Whereas more stable, macrocyclic GCs were well tolerated. These findings seem clinically-relevant because the vast majority of NSF cases are associated with gadodiamide. We also showed that systemic and skin toxicities depend on the baseline renal function, and that hyperphosphataemia sensitizes renally-impaired rats to the fibrotic effects of gadodiamide. Our data suggest that these factors are, actually, risk factors for NSF. We observed in vivo dissociation of two linear GCs, gadodiamide and gadopentetic acid, with gradual release of soluble Gd3+, in renally-impaired rats. Macrocyclic agents remained stable. This observation was also confirmed both in rat and human serum by the relaxometry technique. Our results are also consistent with an interaction between dissociated Gd3+ and serum proteins. We also demonstrated that elevated serum phosphate levels accelerates the release of Gd3+. Taken all together, our results suggest a causal role of dissociated Gd3+ in gadodiamide-induced skin lesions in renally-impaired rats. Finally, we identified the involvement of the canonical signaling pathway of TGFβ, the central mediator of the fibrotic response, in gadodiamide-treated rats with a moderate renal failure. Our work is consistent with a causal role of dissociated Gd in the mechanism of NSF.
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Role of SIRT6 in Myofibroblast Cell DeathSubramanian, Veena January 2016 (has links) (PDF)
Cardiovascular diseases are one of the leading causes of mortality. A common denominator across most of the cardiovascular diseases like diabetic cardiomyopathy, hypertrophic cardiomyopathy, myocardial infarction and dilated cardiomyopathy is the pathological remodelling of heart leading to fibrosis. Cardiac fibrosis is characterized by the excessive production and deposition of extracellular matrix components due to unwarranted proliferation of fibroblasts. Under normal conditions, following cardiac remodelling, my fibroblasts undergo programmed cell death. However, this does not happen under pathological conditions ultimately leading to fibrosis. Although the molecular events and signalling pathways that contribute to the development of cardiac fibrosis is well established, there are limited studies which try to understand the mechanisms by which fibroblasts persist and resist programmed cell death. Here we demonstrate that SIRT6, one of the members of sirtuin family of histone deacetylases, plays an important role in regulating my fibroblast cell death.
When we analysed the mice hearts and isolated fibroblasts deficient in SIRT6, we observed increased expression of my fibroblast markers, suggesting that SIRT6 deficient hearts might have a high proportion of resident my fibroblasts. Also, when SIRT6 deficient fibroblasts were subjected to genotoxic stress, they showed reduced cell death and impaired mitochondrial to nuclear AIF translocation as compared to WT controls. An important regulator of AIF mediated cell death is the protein PARP-1. When we checked the expression levels of this protein under SIRT6 deficient conditions, it was found to be low. PARP-1 was also found to degrade faster under SIRT6 deficient conditions. Further qPCR analysis revealed that the transcript levels of PARP-1 were unaffected by SIRT6 suggesting that the regulation might not be at the transcriptional level. When we studied the acetylation of PARP-1 under SIRT6 deficient conditions we found the protein to be hypo-acetylated indicating a more complex mechanism of regulation.
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Hälsoproblem relaterade till cystisk fibros : en litteraturöversikt / Health problems related to cystic fibrosis : a literature reviewManouilenko Rosales, Camilla, Lindström, Jenny January 2021 (has links)
Bakgrund Cystisk fibros är en multisystemsjukdom som främst påverkar lungor, bukspottkörtel och tarm. Sjukdomen påverkar 70 000 till 100 000 personer globalt i världen. Syfte Syftet var att belysa hälsoproblem hos personer med cystisk fibros. Metod Icke systematisk litteraturöversikt med integrerad analys där litteratursökning tillämpas utifrån databasen PubMed. Artiklarna som inkluderades är publicerade mellan 2011 och 2021. Resultat Baserat på dataanalysen av de 16 inkluderade vetenskapliga artiklarna identifierades fyra teman: fysiska, psykiska, sociala och existentiella hälsoproblem med att leva och överleva med diagnosen cystisk fibros. Slutsats Slutsatsen av denna studie visar att cystisk fibros är en sjukdom som har stor inverkan på både kropp och psyke. Patienter har ett livslångt behov av vård och mer forskning behövs på området för att ytterligare bredda kunskapen om sjukdomen. / Background Cystic fibrosis is a multisystem disease which primarily affects lungs, pancreas and the gut. The disease affects 70,000 to 100,000 globally. Aim The aim of this study was to illustrate the health complications present in patients with cystic fibrosis. Method Non-systematic literature review with integrated analysis where literature search is applied based on the databases PubMed. The articles included in this review are published between 2011 and 2021. Results Four themes were identified based on the analysis of 16 scientific articles: physical, mental, social and existential health problems of living and surviving with the diagnosis of cystic fibrosis. Conclusions The conclusion of this study shows that cystic fibrosis is a disease that has a major impact on both physical and mental health. Patients have a lifelong need for care and more research is needed about the subject to further broaden the knowledge of the disease.
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Estimating steatosis and fibrosis: comparison of acoustic structure quantification with established techniquesKarlas, Thomas, Berger, Joachim, Garnov, Nikita, Lindner, Franziska, Busse, Harald, Linder, Nicolas, Schaudinn, Alexander, Relke, Bettina, Chakaroun, Rima, Tröltzsch, Michael, Wiegand, Johannes, Keim, Volker January 2015 (has links)
To compare ultrasound-based acoustic structure quantification (ASQ) with established non-invasive techniques for grading and staging fatty liver disease.
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Využití sekvenačních metod nové generace pro objasnění fenotypu podobného CF u pacientů s nejasnou molekulární podstatou onemocnění. / Utilization of new generation sequencing methods to elucidate cystic fibrosis-like phenotype at patients with unclear illness of molecular type.Matějčková, Iva January 2017 (has links)
Cystic fibrosis (CF) is genetically conditioned, autosomal recessive disease that occurs in the European population with a prevalence of about 1:2500 - 1:1800. In this disease we observe a mutation of the CTFR gene with subsequent fault in chloride channels. Such afflicted individuals usually suffer from chronic respiratory problems, pancreatic insufficiency, high concentration of chloride ions in sweat and obstructive azoospermia. Genetic testing of CFTR gene is indicated in individuals who meet the CF clinical picture and a positive sweat test (increased concentration of chlorides in the sweat). Genetic testing of the CFTR gene is usually done by using commercial kits detecting the most common mutations of the CFTR gene in the Czech Republic. If the testing results are negative, it is further performed an MLPA method that captures the larger deletions and duplications of gene, eventually a sequencing of all exons is. Despite the well-established algorithm of the testing, some patients suffering from symptoms of CF are left without genetic findings. Thanks to development of next generation sequencing, it is possible to make the diagnosis of CF more effective and uncover the variants that were not captured by previous methods.
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