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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Apoptosis Regulation in Multiple Myeloma

Dimberg, Lina January 2006 (has links)
Multiple myeloma (MM) is a virtually incurable B cell malignancy of the bone marrow. One important part of tumor progression and an obstacle for successful therapy is resistance to apoptosis. To combat this resistance, the mechanisms of apoptosis and survival in MM must be better defined. In this thesis, we identified Fas up-regulation as a mechanism underlying interferon (IFN)-mediated sensitization to Fas-induced apoptosis in the MM cell line U-266-1970. IFN treatment induced activation of signal transducer and activator of transcription (Stat)1 but, intriguingly, also attenuated activation of MM survival factor Stat3. Exploring the role of Stat1 further, we established sub-lines of U-266-1970 with a stable over-expression of Stat1 and of its active mutant Stat1C. These sub-lines displayed a decreased expression and activation of Stat3, and an altered expression of apoptosis-related genes Harakiri, Bcl-2 and Mcl-1. In a drug library screening, Stat1 over-expression was associated with an increased sensitivity to Fas-induced apoptosis and, conversely, an increased resistance to several drugs, including the cyclin dependent kinase (cdk)1 inhibitor CGP74514A. We conclude that Stat1 over-expression does not confer a general resistance or sensitivity to apoptosis in MM, but may strongly affect the response to some specific drugs. We also explored the effects of picropodophyllin (PPP), an inhibitor of the insulin-like growth factor I (IGF-I) receptor tyrosine kinase (RTK), in MM. PPP selectively inhibited the IGF-I RTK activity without inhibiting the insulin RTK activity. Furthermore, PPP potently induced cell cycle arrest and apoptosis in all MM cell lines and patient samples tested, also in the presence of survival factors IGF-I and IL-6. We conclude that PPP has great therapeutic potential in MM Finally, we examined the expression and regulation of the inhibitors of apoptosis proteins (IAPs) in a panel of MM cell lines and patient samples. The glucocorticoid dexamethasone, which is used in MM therapy, induced a transient up-regulation and a subsequent down-regulation of c-IAP2, as well as a down-regulation of XIAP, possibly influencing the sensitivity to apoptosis induced by this drug. Supporting this notion, abrogation of IGF-IR signaling by PPP, which sensitizes MM cells to dexamethasone-induced apoptosis, enhanced the down-regulation of c-IAP2 and XIAP.
22

Análise molecular do gene IAP de Listeria monocytogenes isoladas de alimentos no Rio Grande do Sul / Molecular analisys of iap gene of Listeria monocytogenes isolated from foods on Rio Grande do Sul

Mello, Jozi Fagundes de January 2007 (has links)
A bactéria Listeria monocytogenes é reconhecida como um importante patógeno humano estando amplamente distribuída no ambiente e é responsável pela contaminação de alimentos crus e processados. O mecanismo de patogenicidade é determinado pela presença de genes no cromossomo da bactéria e entre eles estão os genes iap e hly que são essenciais para o mecanismo de invasão e atividade hemolítica do microorganismo, respectivamente. O obejtivo do presente estudo foi confirmar as cepas de L. monocytogenes usando a ténica de PCR para o gene hly e análise da variação nucleotídica do domínio central do gene iap, que é caracterizado pela presença de seqüências repetidas dos aminoácidos treonina e asparagina. Vinte e seis cepas de L. mnocytogenes, previamente isoladas de produtos lácteos e identificdas por métodos clássicos, se mostraram positivas para a PCR espécie-específico e então submetidas à determinação da seqüência nucleotídica. Os resultados mostraram variações na seqüência nucleotídica contendo substituições, inserções, deleções e um número de seqüências similares entre as cepas isoladas e a cepa controle EGD-e. Vinte e três cepas exibiram a mesma deleção que compreende 24 pares de bases dentro da seqüência de repetição e alterações similares na proteína traduzida. Apenas três cepas mostraram tamanhos diferentes de deleções e diferentes alterações na proteína. De acordo com estes resultados, a maioria das cepas apresentou uma característica molecular comum, diferentes da cepa padrão e este perfil predominante pode ser considerado como a característica das L. monocytogenes isoladas de produtos lácteos no Sul do Brasil. / The bacterium Listeria monocytogenes is recognized as an important human pathogen being omnipresent in the environment and is responsible for contamination in raw and processed foods. The mechanism of pathogenicity is established by presence of some genes on chromosome of bacteria between them, iap and hly genes that are essential to the invasion mechanism and hemolytic activity of microorganism, respectively. The aim of present study was confirm the strain L. monocytogenes using PCR to hly gene and analysis the nucleotide variability of central domain of iap gene characterized by the presence of similar sequences of threonine and asparagine amino acids. Twenty-six strains previously isolated from dairy products and classified by classic methods to L. monocytogenes were positive to specie-specific PCR and than submitted to nucleotide sequence determination. The results showed a sequence variation containing nucleotide substitutions, insertions, deletions and a number of repeated sequences among the isolates and control strain EGD-e. Twenty-three strains exhibited the same gap that includes a deletion of 24 base pairs inside of the repeated sequence and similar alterations in the translated protein. Just three strains showed different sizes of gaps and different protein alterations. According to these results, the majority strains displayed a common molecular characteristic different from the strain pattern and this predominant profile can be considerate as characteristic to L. monocytogenes isolated from dairy products in South Brazil.
23

Análise molecular do gene IAP de Listeria monocytogenes isoladas de alimentos no Rio Grande do Sul / Molecular analisys of iap gene of Listeria monocytogenes isolated from foods on Rio Grande do Sul

Mello, Jozi Fagundes de January 2007 (has links)
A bactéria Listeria monocytogenes é reconhecida como um importante patógeno humano estando amplamente distribuída no ambiente e é responsável pela contaminação de alimentos crus e processados. O mecanismo de patogenicidade é determinado pela presença de genes no cromossomo da bactéria e entre eles estão os genes iap e hly que são essenciais para o mecanismo de invasão e atividade hemolítica do microorganismo, respectivamente. O obejtivo do presente estudo foi confirmar as cepas de L. monocytogenes usando a ténica de PCR para o gene hly e análise da variação nucleotídica do domínio central do gene iap, que é caracterizado pela presença de seqüências repetidas dos aminoácidos treonina e asparagina. Vinte e seis cepas de L. mnocytogenes, previamente isoladas de produtos lácteos e identificdas por métodos clássicos, se mostraram positivas para a PCR espécie-específico e então submetidas à determinação da seqüência nucleotídica. Os resultados mostraram variações na seqüência nucleotídica contendo substituições, inserções, deleções e um número de seqüências similares entre as cepas isoladas e a cepa controle EGD-e. Vinte e três cepas exibiram a mesma deleção que compreende 24 pares de bases dentro da seqüência de repetição e alterações similares na proteína traduzida. Apenas três cepas mostraram tamanhos diferentes de deleções e diferentes alterações na proteína. De acordo com estes resultados, a maioria das cepas apresentou uma característica molecular comum, diferentes da cepa padrão e este perfil predominante pode ser considerado como a característica das L. monocytogenes isoladas de produtos lácteos no Sul do Brasil. / The bacterium Listeria monocytogenes is recognized as an important human pathogen being omnipresent in the environment and is responsible for contamination in raw and processed foods. The mechanism of pathogenicity is established by presence of some genes on chromosome of bacteria between them, iap and hly genes that are essential to the invasion mechanism and hemolytic activity of microorganism, respectively. The aim of present study was confirm the strain L. monocytogenes using PCR to hly gene and analysis the nucleotide variability of central domain of iap gene characterized by the presence of similar sequences of threonine and asparagine amino acids. Twenty-six strains previously isolated from dairy products and classified by classic methods to L. monocytogenes were positive to specie-specific PCR and than submitted to nucleotide sequence determination. The results showed a sequence variation containing nucleotide substitutions, insertions, deletions and a number of repeated sequences among the isolates and control strain EGD-e. Twenty-three strains exhibited the same gap that includes a deletion of 24 base pairs inside of the repeated sequence and similar alterations in the translated protein. Just three strains showed different sizes of gaps and different protein alterations. According to these results, the majority strains displayed a common molecular characteristic different from the strain pattern and this predominant profile can be considerate as characteristic to L. monocytogenes isolated from dairy products in South Brazil.
24

Un retrovirus endogène défectif code un antigène reconnu par des lymphocytes T cytolytiques sur une leucémie murine spontanée

de Brouchoven de Bergeyck, Vinciane 12 October 1994 (has links)
Les tumeurs spontanées de souris ne sont pas immunogéniques. Néanmoins la mutagenèse de la leucémie spontanée LEC a permis d'isoler des variants immunogéniques qui confèrent une protection contre la tumeur parentale. Des clones de lymphocytes T cytolytiques (CTL) reconnaissant les cellules LEC ont été isolés à partir des lymphocytes de souris immunes. Au cours de ce travail, nous avons isolé et caractérisé la séquence codant l'antigène LEC A reconnu par le clone CTL-LEC1:5 à la surface des cellules LEC. Pour cloner ce gène, nous avons suivi une démarche similaire à celle ayant permis l'isolement de plusieurs gènes codant des antigènes reconnus par des clones CTL à la surface du mastocytome murin P815. Cette approche est basée sur la transfection de bibliothèques de cosmides construites avec l'ADN des cellules exprimant les antigènes à analyser et sur la détection des transfectants exprimant ces antigènes grâce à leur capacité de stimuler la prolifération du clone CTL adéquat. Une bibliothèque de cosmides a été construite avec l'ADN des cellules LEC et a été transfectée dans les cellules P1.HTR.KkDk. Plusieurs transfectants stimulant la prolifération des CTL LEC1:5 ont été identifiés. Un cosmide capable de transférer l'expression de l'antigène LEC A a été obtenu en encapsidant l'ADN génomique d'un transfectant dans des têtes de phage lambda. Un fragment de 4,38 kb codant l'antigène LEC A a été isolé à partir de ce cosmide. La séquence nucléotidique de ce fragment a été comparée aux séquences répertoriées dans les banques de données. Cette séquence présente de fortes homologies avec les rétrovirus endogènes défectifs appartenant à la famille IAP (intracisternal A particle, ou particule intraciternale de type A). La séquence codant l'antigène LEC A a été appelée LEC A IAP. Les CTL LEC1:5 reconnaissent un peptide antigénique dérivant de la région gag de l'élément LEC A IAP en association avec la molécule H 2 Dk. Pour comprendre le mécanisme responsable de l'expression de l'antigène LEC A par les cellules LEC, nous avons comparé les ADN génomiques des cellules LEC, de deux tumeurs syngéniques non reconnues par les CTL-LEC1:5 et de cellules normales provenant de souris syngéniques. Un Southern blot et des réactions de polymérisation en chaîne (PCR) ont permis d'établir que l'élément LEC A IAP s'est transposé dans la tumeur LEC. L'analyse de l'ADN génomique de variants des cellules LEC n'exprimant plus l'antigène LEC A ont établi que la transposition de l'élément LEC A IAP était responsable de l'expression de cet antigène. Il paraît probable que la transposition a pour conséquence d'activer la transcription de cet élément IAP, ce qui entraîne la production de l'antigène. / Cytolytic T lymphocyte (CTL) clones directed against spontaneous mouse leukemia LEC have been obtained. By transfecting a cosmid library into cells which were then tested for their ability to stimulate the CTL, we identified the gene coding for the antigen recognized by one of these CTL clones. It is the gag gene of an endogenous defective retrovirus that belongs to the intracisternal A particle (IAP) family. A gag-encoded nonapeptide presented by the H-2 Dk molecule caused recognition by the anti-LEC CTL clone. Southern blot and polymerase chain reaction analyses indicated that the expression of the antigen by the LEC tumor cell line resulted from the transposition of an IAP sequence into a new genomic location.
25

Avaliação da expressão de genes e proteínas anti- e pró-apoptóticos em pacientes com diabetes mellitus tipo 1 e esclerose múltipla submetidos ao transplante autólogo de células-tronco hematopoéticas / Evaluation of anti and proapoptotic gene and protein expression in type 1 diabetes mellitus and multiple sclerosis patients submitted to autologous hematopoietic stem cell transplantation

Oliveira, Gislane Lelis Vilela de 17 October 2008 (has links)
O diabetes mellitus tipo 1 (DM-1) e a esclerose múltipla (EM) são doenças auto-imunes órgão-específicas, inflamatórias, mediadas por células T e B auto-reativas e caracterizadas pela destruição seletiva de células b pancreáticas produtoras de insulina e do sistema nervoso central, respectivamente. Acredita-se que a desregulação da expressão de genes reguladores da maquinaria apoptótica possa contribuir para o desenvolvimento da auto-imunidade, visto que algumas dessas moléculas participam nos processos de tolerância central e periférica de linfócitos auto-reativos. O objetivo deste projeto foi analisar a expressão de moléculas reguladoras das vias intrínseca, extrínseca e da Família de proteínas inibidoras da apoptose (IAP) em 33 indivíduos saudáveis, 15 pacientes com DM-1 e 18 com EM submetidos à terapia de imunossupressão em altas doses seguida do transplante autólogo de células-tronco hematopoéticas (IAD/TACTH). As células mononucleares (CMN) foram isoladas do sangue periférico dos controles e de pacientes nos períodos pré-mobilização (pré-mob), pré-condicionamento (pré-cond), D+180, D+360, D+540 e D+720 pós-transplante. As CMN foram utilizadas para extração de RNA, síntese de cDNA, quantificação da expressão por PCR em tempo real dos genes a1, bcl-2, bcl-w, bcl-xL, mcl-1, bad, bak, bax, bid, bik, bim, bok, noxa, fas, fasL, c-FLIPL, cIAP-1 e cIAP-2 e protéica de Bcl-2, Bcl-xL, Bak, Bim e c-FLIPL por western-blotting. Os resultados de expressão gênica foram representados por unidades relativas de expressão em medianas nas diferentes amostras. Os pacientes com DM-1 apresentaram diminuição da expressão dos genes anti-apoptóticos bcl-2 (mediana: 0,98; p=0,04), bcl-w (0,08; p=0,04), mcl-1 (1254; p=0,03) e cIAP-1 (1,24; p=0,003) nas CMN dos pacientes no período pré-mob em relação aos indivíduos saudáveis (medianas: bcl-2: 7,58; bcl-w: 0,52; mcl-1: 1659; cIAP-1: 14,5), enquanto a expressão de cIAP-2 (60,8; p=0,0005) estava aumentada em relação aos controles (23,3). Foi observada redução significativa na expressão dos genes pró-apoptóticos bad (0,002; p<0,0001), bax (0,01; p=0,002) e fasL (1,66; p=0,001) no período pré-mob comparada aos controles sadios (bad: 0,23; bax: 2,79; fasL: 3,56). Os níveis de RNAm de bid (0,10; p=0,001) e bok (0,72; p=0,006) estavam elevados no pré-mob em relação ao grupo controle (bid: 0,004; bok: 0,31). As moléculas bcl-2, bcl-w, bcl-xL, mcl-1, bad, bax, bok, fasL e cIAP-1 atingiram níveis de RNAm similares aos controles após o TACTH. Foi verificado que a expressão de bcl-w, cIAP-1 e noxa estava maior nos pacientes com DM-1 em remissão quando comparados àqueles em recaída. A diminuição da expressão de a1, bcl-2 e bcl-w e o aumento de fas e noxa correlacionaram-se às porcentagens de hemoglobina glicosilada, concentração de auto-anticorpos GAD65, e aos níveis séricos de peptídeo-C após o transplante. Os pacientes com EM mostraram uma expressão reduzida dos genes anti-apoptóticos bcl-w (0,11; p=0,02) e cIAP-1 (1,87; p=0,04) no pré-mob comparada aos valores dos controles (bcl-w: 0,27; cIAP-1: 7,75) e maior expressão dos genes a1 (90,8; p=0,001) e cIAP-2 (58,8; p=0,009) em relação aos controles (a1: 12,7; cIAP-2: 22,3). As moléculas pró-apoptóticas bad (0,007; p=0,01) e bax (0,0007; p=0,004) mostraram menor expressão nas CMN no período pré-mob do que nos controles (bad: 0,27; bax: 1,24). Os genes bid (20,7; p=0,004), bik (0,84; p=0,02) e bok (1,77; p=0,0001) possuíam maior expressão no período pré-mob em relação aos indivíduos sadios (bid: 2,64; bik: 0,33; bok: 0,26). Não foram observadas diferenças significativas na expressão das moléculas da via extrínseca da apoptose nos pacientes com EM (p>0,05) nos períodos avaliados. Os valores de expressão de bcl-w, bak, bax, bik, bok e cIAP-1 atingiram níveis semelhantes aos controles após o transplante. A expressão dos genes bcl-2, cIAP-1, bad e bax estava maior nos pacientes em remissão da EM quando comparados àqueles em progressão neurológica. O aumento da expressão dos genes pró-apoptóticos bax, bak e bimEL correlacionou-se inversamente aos valores de EDSS dos pacientes com EM após o TACTH. Os resultados de expressão protéica foram equivalentes aos de expressão gênica nas duas doenças, com exceção dos dados das proteínas Bcl-2 e Bim. Em conjunto, os resultados demonstraram a desregulação da expressão de várias moléculas anti- e pró-apoptóticas nas CMN dos pacientes com DM-1 e EM. Esses achados sugerem a associação de alterações nos processos de apoptose celular com o surgimento e persistência de células auto-reativas no DM-1 e EM. Os dados indicam que essas alterações, principalmente a diminuição da expressão de moléculas pró-apoptóticas, como bak e bax, possam contribuir para a patogênese do DM-1 e EM. Além disso, a terapia de IAD/TACTH foi capaz de modular a expressão da maioria dos genes anormalmente expressos nas CMN dos pacientes com DM-1 e EM, já que esses atingiram níveis de expressão similares ao grupo controle após o transplante. Esta normalização da expressão de vários genes analisados correlacionou-se com a remissão clínica da doença na maioria dos pacientes / Type 1 diabetes mellitus (T1DM) and multiple sclerosis (MS) are inflammatory, organ-specific autoimmune diseases characterized by selective destruction of insulin-producing pancreatic -cells and central nervous system, respectively, by autoreactive B and T cells. Deregulation of apoptotic machinery is supposed to contribute to self-tolerance breakdown and autoimmune diseases pathogenesis, since apoptotic molecules have an important role in B and T lymphocytes central and peripheral tolerance mechanisms. The aim of this study was to evaluate the expression of pro and anti-apoptotic molecules from intrinsic and extrinsic apoptotic pathways and IAP Family members in 33 healthy individuals, 15 T1DM and 18 MS patients submitted to high-dose immunossupression therapy followed by autologous hematopoietic stem cell transplantation (HDI/AHSCT). Peripheral blood mononuclear cells (PBMC) were isolated from controls and patients at pre-mobilization (pre-mob), pre-conditioning (pre-cond), D+180, D+360, D+540 and D+720 post-transplantation. PBMC were used for RNA extraction, cDNA synthesis, gene quantification of a1, bcl-2, bcl-w, bcl-xL, bad, bak, bax, bid, bik, bimEL, bok, noxa, fas, fasL, c-FLIPL, cIAP-1 and cIAP-2 by Real Time PCR and Bcl-2, Bcl-xL, Bak, BimEL and c-FLIPL proteins detection by western-blotting. Results are expressed as median of relative expression units. Results from T1DM patients indicated that antiapoptotic molecules bcl-2 (median: 0,98; p=0,04), bcl-w (0,08; p=0,04), mcl-1 (1254; p=0,03) and cIAP-1 (1,24; p=0,003) were downregulated at pre-mob compared with healthy controls (medians bcl-2: 7,58; bcl-w: 0,52; mcl-1: 1659; cIAP-1: 14,5), while cIAP-2 (60,8; p=0,0005) gene expression was upregulated compared to healthy controls (23,3). We observed a significant decrease in proapoptotic bad (0,002; p<0,0001), bax (0,01; p=0,002) and fasL (1,66; p=0,001) genes expression in patients PBMC at pre-mob period compared to healthy subjects (bad: 0,23; bax: 2,79; fasL: 3,56). mRNA levels of bid (0.10; p=0.001) and bok (0.72; p=0.006) were elevated at pre-mob period when compared to control group (bid: 0.004; bok: 0.31). The bcl-2, bcl-w, bcl-xL, mcl-1, bad, bak, bax, bok, fasL and cIAP-1 mRNA levels reached controls levels after HDI/AHSCT. We observed that bcl-w, cIAP-1 and noxa gene expression were increased in T1DM patients in remission when compared to relapsed patients. The decreased antiapoptotic gene expression and increased in proapoptotic molecules correlated with decreased glicosilated hemoglobin percentages (Hb A1C) and anti-GAD65 antibodies and increased peptide-C levels. Results from MS patients showed decreased bcl-w (0,11; p=0,02) and cIAP-1 gene expression (1,87; p=0,04) in patients PBMC at pre-mob period compared to healthy controls (bcl-w: 0,27; cIAP-1: 7,75) and increased expression of a1 (90,8; p=0,001) and cIAP-2 (58,8; p=0,009) compared to controls (a1: 12,7; cIAP-2: 22,3). Proapoptotic molecules bad (0.007; p=0.01) and bax (0.0007; p=0.004) showed decreased gene expression at pre-mob compared to control group (bad: 0.27; bax: 1.24). bid (20.7; p=0.004), bik (0.84; p=0.01) and bok genes (1.77; p=0.0001) showed increased expression at pre-mob compared to healthy controls (bid: 2.64; bik: 0.33; bok: 0.26). Significant differences were not observed in the expression of the extrinsic pathway genes in pre-mob and healthy controls samples (p>0.05). bcl-w, bak, bax, bik, bok and cIAP-1 expression values reached healthy control values after transplantation. We observed that bcl-2, cIAP-1, bad and bax gene expression was increased in MS patients in disease remission when compared to patients with neurologic progression. Significant correlation of increased proapoptotic genes expression with decreased EDSS values in MS patients after HDI/AHSCT was observed. Results of protein quantification of apoptotic molecules in PBMC of T1DM and MS patients were similar to the gene expression results of these molecules, except for Bcl-2 and Bim proteins. Taken together, these data indicate a deregulated expression of anti- and proapoptotic genes in T1DM and MS patients PBMC. These data suggest an association of deregulated apoptosis with emergence and maintenance of autoreactive lymphocytes in analyzed patients. Based on these results, we suggest that this altered gene expression profile, mainly the decreased proapoptotic genes expression, as bak and bax, may contribute to T1DM and MS pathogenesis. Furthermore, we showed that the HDI/AHSCT therapy was able to modulate and normalize the expression of most genes abnormally expressed in T1DM and MS patients at pre-transplant period. Many analyzed genes achieved expression levels similar to healthy controls. The normalization of the expression of many evaluated genes correlated to disease remission in the majority of the patients.
26

Avaliação da expressão de genes e proteínas anti- e pró-apoptóticos em pacientes com diabetes mellitus tipo 1 e esclerose múltipla submetidos ao transplante autólogo de células-tronco hematopoéticas / Evaluation of anti and proapoptotic gene and protein expression in type 1 diabetes mellitus and multiple sclerosis patients submitted to autologous hematopoietic stem cell transplantation

Gislane Lelis Vilela de Oliveira 17 October 2008 (has links)
O diabetes mellitus tipo 1 (DM-1) e a esclerose múltipla (EM) são doenças auto-imunes órgão-específicas, inflamatórias, mediadas por células T e B auto-reativas e caracterizadas pela destruição seletiva de células b pancreáticas produtoras de insulina e do sistema nervoso central, respectivamente. Acredita-se que a desregulação da expressão de genes reguladores da maquinaria apoptótica possa contribuir para o desenvolvimento da auto-imunidade, visto que algumas dessas moléculas participam nos processos de tolerância central e periférica de linfócitos auto-reativos. O objetivo deste projeto foi analisar a expressão de moléculas reguladoras das vias intrínseca, extrínseca e da Família de proteínas inibidoras da apoptose (IAP) em 33 indivíduos saudáveis, 15 pacientes com DM-1 e 18 com EM submetidos à terapia de imunossupressão em altas doses seguida do transplante autólogo de células-tronco hematopoéticas (IAD/TACTH). As células mononucleares (CMN) foram isoladas do sangue periférico dos controles e de pacientes nos períodos pré-mobilização (pré-mob), pré-condicionamento (pré-cond), D+180, D+360, D+540 e D+720 pós-transplante. As CMN foram utilizadas para extração de RNA, síntese de cDNA, quantificação da expressão por PCR em tempo real dos genes a1, bcl-2, bcl-w, bcl-xL, mcl-1, bad, bak, bax, bid, bik, bim, bok, noxa, fas, fasL, c-FLIPL, cIAP-1 e cIAP-2 e protéica de Bcl-2, Bcl-xL, Bak, Bim e c-FLIPL por western-blotting. Os resultados de expressão gênica foram representados por unidades relativas de expressão em medianas nas diferentes amostras. Os pacientes com DM-1 apresentaram diminuição da expressão dos genes anti-apoptóticos bcl-2 (mediana: 0,98; p=0,04), bcl-w (0,08; p=0,04), mcl-1 (1254; p=0,03) e cIAP-1 (1,24; p=0,003) nas CMN dos pacientes no período pré-mob em relação aos indivíduos saudáveis (medianas: bcl-2: 7,58; bcl-w: 0,52; mcl-1: 1659; cIAP-1: 14,5), enquanto a expressão de cIAP-2 (60,8; p=0,0005) estava aumentada em relação aos controles (23,3). Foi observada redução significativa na expressão dos genes pró-apoptóticos bad (0,002; p<0,0001), bax (0,01; p=0,002) e fasL (1,66; p=0,001) no período pré-mob comparada aos controles sadios (bad: 0,23; bax: 2,79; fasL: 3,56). Os níveis de RNAm de bid (0,10; p=0,001) e bok (0,72; p=0,006) estavam elevados no pré-mob em relação ao grupo controle (bid: 0,004; bok: 0,31). As moléculas bcl-2, bcl-w, bcl-xL, mcl-1, bad, bax, bok, fasL e cIAP-1 atingiram níveis de RNAm similares aos controles após o TACTH. Foi verificado que a expressão de bcl-w, cIAP-1 e noxa estava maior nos pacientes com DM-1 em remissão quando comparados àqueles em recaída. A diminuição da expressão de a1, bcl-2 e bcl-w e o aumento de fas e noxa correlacionaram-se às porcentagens de hemoglobina glicosilada, concentração de auto-anticorpos GAD65, e aos níveis séricos de peptídeo-C após o transplante. Os pacientes com EM mostraram uma expressão reduzida dos genes anti-apoptóticos bcl-w (0,11; p=0,02) e cIAP-1 (1,87; p=0,04) no pré-mob comparada aos valores dos controles (bcl-w: 0,27; cIAP-1: 7,75) e maior expressão dos genes a1 (90,8; p=0,001) e cIAP-2 (58,8; p=0,009) em relação aos controles (a1: 12,7; cIAP-2: 22,3). As moléculas pró-apoptóticas bad (0,007; p=0,01) e bax (0,0007; p=0,004) mostraram menor expressão nas CMN no período pré-mob do que nos controles (bad: 0,27; bax: 1,24). Os genes bid (20,7; p=0,004), bik (0,84; p=0,02) e bok (1,77; p=0,0001) possuíam maior expressão no período pré-mob em relação aos indivíduos sadios (bid: 2,64; bik: 0,33; bok: 0,26). Não foram observadas diferenças significativas na expressão das moléculas da via extrínseca da apoptose nos pacientes com EM (p>0,05) nos períodos avaliados. Os valores de expressão de bcl-w, bak, bax, bik, bok e cIAP-1 atingiram níveis semelhantes aos controles após o transplante. A expressão dos genes bcl-2, cIAP-1, bad e bax estava maior nos pacientes em remissão da EM quando comparados àqueles em progressão neurológica. O aumento da expressão dos genes pró-apoptóticos bax, bak e bimEL correlacionou-se inversamente aos valores de EDSS dos pacientes com EM após o TACTH. Os resultados de expressão protéica foram equivalentes aos de expressão gênica nas duas doenças, com exceção dos dados das proteínas Bcl-2 e Bim. Em conjunto, os resultados demonstraram a desregulação da expressão de várias moléculas anti- e pró-apoptóticas nas CMN dos pacientes com DM-1 e EM. Esses achados sugerem a associação de alterações nos processos de apoptose celular com o surgimento e persistência de células auto-reativas no DM-1 e EM. Os dados indicam que essas alterações, principalmente a diminuição da expressão de moléculas pró-apoptóticas, como bak e bax, possam contribuir para a patogênese do DM-1 e EM. Além disso, a terapia de IAD/TACTH foi capaz de modular a expressão da maioria dos genes anormalmente expressos nas CMN dos pacientes com DM-1 e EM, já que esses atingiram níveis de expressão similares ao grupo controle após o transplante. Esta normalização da expressão de vários genes analisados correlacionou-se com a remissão clínica da doença na maioria dos pacientes / Type 1 diabetes mellitus (T1DM) and multiple sclerosis (MS) are inflammatory, organ-specific autoimmune diseases characterized by selective destruction of insulin-producing pancreatic -cells and central nervous system, respectively, by autoreactive B and T cells. Deregulation of apoptotic machinery is supposed to contribute to self-tolerance breakdown and autoimmune diseases pathogenesis, since apoptotic molecules have an important role in B and T lymphocytes central and peripheral tolerance mechanisms. The aim of this study was to evaluate the expression of pro and anti-apoptotic molecules from intrinsic and extrinsic apoptotic pathways and IAP Family members in 33 healthy individuals, 15 T1DM and 18 MS patients submitted to high-dose immunossupression therapy followed by autologous hematopoietic stem cell transplantation (HDI/AHSCT). Peripheral blood mononuclear cells (PBMC) were isolated from controls and patients at pre-mobilization (pre-mob), pre-conditioning (pre-cond), D+180, D+360, D+540 and D+720 post-transplantation. PBMC were used for RNA extraction, cDNA synthesis, gene quantification of a1, bcl-2, bcl-w, bcl-xL, bad, bak, bax, bid, bik, bimEL, bok, noxa, fas, fasL, c-FLIPL, cIAP-1 and cIAP-2 by Real Time PCR and Bcl-2, Bcl-xL, Bak, BimEL and c-FLIPL proteins detection by western-blotting. Results are expressed as median of relative expression units. Results from T1DM patients indicated that antiapoptotic molecules bcl-2 (median: 0,98; p=0,04), bcl-w (0,08; p=0,04), mcl-1 (1254; p=0,03) and cIAP-1 (1,24; p=0,003) were downregulated at pre-mob compared with healthy controls (medians bcl-2: 7,58; bcl-w: 0,52; mcl-1: 1659; cIAP-1: 14,5), while cIAP-2 (60,8; p=0,0005) gene expression was upregulated compared to healthy controls (23,3). We observed a significant decrease in proapoptotic bad (0,002; p<0,0001), bax (0,01; p=0,002) and fasL (1,66; p=0,001) genes expression in patients PBMC at pre-mob period compared to healthy subjects (bad: 0,23; bax: 2,79; fasL: 3,56). mRNA levels of bid (0.10; p=0.001) and bok (0.72; p=0.006) were elevated at pre-mob period when compared to control group (bid: 0.004; bok: 0.31). The bcl-2, bcl-w, bcl-xL, mcl-1, bad, bak, bax, bok, fasL and cIAP-1 mRNA levels reached controls levels after HDI/AHSCT. We observed that bcl-w, cIAP-1 and noxa gene expression were increased in T1DM patients in remission when compared to relapsed patients. The decreased antiapoptotic gene expression and increased in proapoptotic molecules correlated with decreased glicosilated hemoglobin percentages (Hb A1C) and anti-GAD65 antibodies and increased peptide-C levels. Results from MS patients showed decreased bcl-w (0,11; p=0,02) and cIAP-1 gene expression (1,87; p=0,04) in patients PBMC at pre-mob period compared to healthy controls (bcl-w: 0,27; cIAP-1: 7,75) and increased expression of a1 (90,8; p=0,001) and cIAP-2 (58,8; p=0,009) compared to controls (a1: 12,7; cIAP-2: 22,3). Proapoptotic molecules bad (0.007; p=0.01) and bax (0.0007; p=0.004) showed decreased gene expression at pre-mob compared to control group (bad: 0.27; bax: 1.24). bid (20.7; p=0.004), bik (0.84; p=0.01) and bok genes (1.77; p=0.0001) showed increased expression at pre-mob compared to healthy controls (bid: 2.64; bik: 0.33; bok: 0.26). Significant differences were not observed in the expression of the extrinsic pathway genes in pre-mob and healthy controls samples (p>0.05). bcl-w, bak, bax, bik, bok and cIAP-1 expression values reached healthy control values after transplantation. We observed that bcl-2, cIAP-1, bad and bax gene expression was increased in MS patients in disease remission when compared to patients with neurologic progression. Significant correlation of increased proapoptotic genes expression with decreased EDSS values in MS patients after HDI/AHSCT was observed. Results of protein quantification of apoptotic molecules in PBMC of T1DM and MS patients were similar to the gene expression results of these molecules, except for Bcl-2 and Bim proteins. Taken together, these data indicate a deregulated expression of anti- and proapoptotic genes in T1DM and MS patients PBMC. These data suggest an association of deregulated apoptosis with emergence and maintenance of autoreactive lymphocytes in analyzed patients. Based on these results, we suggest that this altered gene expression profile, mainly the decreased proapoptotic genes expression, as bak and bax, may contribute to T1DM and MS pathogenesis. Furthermore, we showed that the HDI/AHSCT therapy was able to modulate and normalize the expression of most genes abnormally expressed in T1DM and MS patients at pre-transplant period. Many analyzed genes achieved expression levels similar to healthy controls. The normalization of the expression of many evaluated genes correlated to disease remission in the majority of the patients.
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有線寬頻服務產業競爭策略分析

林茂陽, Lin, Mao-Yang Unknown Date (has links)
由於數位化技術的啟動、網際網路的應用、電訊傳播政策的解禁,使得傳播產業、通訊產業發生「典範轉移」,將原本完全獨立的電信產業、有線電視產業與網際網路產業匯流合而為一,而寬頻的驅力更促使匯聚與整合。 有線電視與電信服務的互跨經營、新固網業者的加入,在這「競爭」的寬頻網路服務產業,匯聚使得市場形貌改變,也產生管理的典範轉移。典範轉移後的策略思考與策略規劃就成為寬頻服務經營者必須加以思索並具體因應。 本研究主要探討,寬頻服務產業現況發展,機會與威脅、新固網加入後,寬頻服務產業競爭分析,其相對優劣勢、寬頻服務產業未來發展形貌、寬頻服務產業關鍵成功因素、寬頻服務經營者策略模式分析;結論如下: 寬頻服務經營者需建置一啟動網路效應產生價值的整合服務平台,平台機制的完善、提供多元創新加值的服務為關鍵成功因素。寬頻服務經營者所提供的服務可以IDC為寬頻服務後勤系統,以此為寬頻入口,不斷蓄積更多服務,以內容為驅力,吸引寬頻服務用戶續留於此,不斷累積並創造價值。 寬頻服務具有規模經濟與範疇經濟的特性,實體傳輸網路建設成本高,唯有擴大經營規模,獲取邊際成本遞減的效益,才能充分降低成本。另一方面,服務項目的增加,並不會大幅改變其所投入的建設成本,若有線電視與電信事業兩者相互經營合作,將促使其服務、技術更進步,更節省架設網路、人事管理與行銷等經營成本,同時也將提供更多樣化的服務,進而擴大其經營績效。 發展以電視為作業平台的寬頻服務,掌握電視與有線電視的普及率,是有線寬頻服務經營者的發展的利基。關鍵在於視訊轉換盒(Set-Top-Box)與操作環境。發展以「遙控器」「電視」為思考操作介面環境,更為接近人性化寬頻服務,以「家庭用戶」「數位娛樂影音服務」的寬頻服務,區分以「鍵盤」「PC」「數據服務」的電信寬頻服務。 另核心能力的運用,動態能耐的轉移也是關鍵。以過去核心能力轉移至寬頻服務的能力,整合寬頻內容服務提供者,提供多元寬頻服務內容以內容為驅力作為發展策略依據。未來寬頻服務一定是合作大於競爭,集團合作發揮綜效,共享資源與價值活動。唯有上下游整合的完整寬頻服務提供體系,才能在大者恆大的市場競局中存活。
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Vliv řízení průtoku vzduchu hlasivkami na dynamickou stabilizaci stoje / Influence of airflow control with vocal cords on dynamic stand stabilization

Rybáčková, Kristýna January 2019 (has links)
Title: The effect of airway control on stance dynamic stability Objectives: The aim of this thesis is to find out whether and how will the influence of vocal cords modulation be manifested on the dynamic stabilization of the standing body during translational shifts of the supporting surface of different intensities and A-P directions. Thus, building on the findings of Massery et al (2013). Methods: The thesis has the character of qualitative research. The experiment was attended by 23 healthy probands, of which 7 men and 16 women aged 20-40 years. Spirometry was used to test the objectivity of airway airflow during breathing / phoning maneuvers with different vocal cords positioning and dynamic computer posturography using the Neurocom Smart Equi Test System and its Motor Control Test, which evaluated the effectiveness of automatic postural responses. We connected the posturograph with the spirometer using the Kistler accelerometer (type 8766A100BB). The course of the experiment was simultaneously recorded by a camera (GoPro Hero 7). The Smart EquiTest System generated three postural perturbations of different intensity (S - sub treshold, M - threshold, L - saturating) in two directions (anterior translation / posterior translation). The measured data were then processed in the program Neurocom...
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La metodología de Gamificación para el aprendizaje de historia de la educación española: investigación acción en la formación universitaria de docentes

Edo Agustín, Esther 23 December 2021 (has links)
[ES] La presente tesis doctoral parte de la pregunta de investigación ¿es la Gamificación una metodología eficaz para el aprendizaje de historia de la educación española en la formación universitaria de futuros docentes? Cuatro ejes, explícitos en esta pregunta, son los que estructuran esta investigación educativa. El primero es la metodología de Gamificación, que fundamenta y conforma la investigación llevada a cabo. El segundo es la historia de la educación española, el contenido impartido a través de la experiencia gamificada. El tercero representa el contexto universitario en el que se desarrolla la investigación. Finalmente, el cuarto muestra la población con la que se hace el estudio de campo, alumnado de los grados de Magisterio de Infantil y Primaria. Este último eje tiene especial relevancia, ya que el desarrollo de investigación acción con futuros docentes se integra en la cartografía de la buena docencia universitaria (Paricio et al., 2019) y en la investigación desde el vínculo y la transferibilidad del conocimiento pedagógico durante el proceso. Los últimos estudios sobre Gamificación abogan por extraer resultados que evidencien el efecto de la Gamificación en variables más allá de la motivación. Además, enfatizan la necesidad de abordar la investigación desde un enfoque cualitativo y cuantitativo. La presente tesis atiende a estas premisas, por ello, con la finalidad de dar respuesta a la pregunta de investigación y comprobar las diferentes hipótesis, se acota un conjunto de variables cualitativas y cuantitativas. Las más significativas son metodología de Gamificación, competencias específicas, competencias transversales, motivación, rendimiento académico, rol docente y juego como recurso didáctico. Además, se utiliza un método mixto de investigación que combina un análisis cualitativo, ratificado con diferentes análisis cuantitativos para aportar validez ecológica a la investigación y mayor rigor a las conclusiones. Entre las conclusiones más relevantes destacan la satisfacción de los sujetos participantes hacia la experiencia gamificada, la mejora de las competencias específicas y el desarrollo de diferentes competencias transversales. Se logra también un incremento en la motivación y un buen rendimiento académico. Respecto al rol docente, la valoración es positiva, al igual que el juego como recurso didáctico. Los diferentes análisis también aportan conclusiones destacables relacionadas con el carácter ecléctico de la metodología, el éxito en la asistencia, la capacidad de atención, el grado de participación, la evaluación, la atención a la diversidad de alumnado o la percepción del propio proceso de aprendizaje. Además, esta investigación acción considera los últimos estudios en Gamificación e investigación educativa y responde a las demandas y retos que estos plantean. De este modo, trata de lograr la proyección internacional a la que se aspira con esta tesis doctoral y colabora en la creación de conocimiento empírico en el campo de la Gamificación. / [CA] La present tesi doctoral part de la pregunta d'investigació ¿és la Gamificació una metodologia eficaç per a l'aprenentatge d'història de l'educació espanyola en la formació universitària de futurs docents? Quatre eixos, explícits en aquesta pregunta, són els que estructuren aquesta investigació educativa. El primer és la metodologia de Gamificació, que fonamenta i conforma la investigació duta a terme. El segon és la història de l'educació espanyola, el contingut impartit a través de l'experiència gamificada. El tercer representa el context universitari en el qual es desenvolupa la investigació. Finalment, el quart mostra la població amb la qual es fa l'estudi de camp, alumnat dels graus de Magisteri d'Infantil i Primària. Aquest últim eix té especial rellevància, ja que el desenvolupament d'investigació acció amb futurs docents s'integra en la cartografia de la bona docència universitària (Paricio et al., 2019) i en la investigació des del vincle i la transferibilitat del coneixement pedagògic durant el procés. Els últims estudis sobre Gamificació advoquen per extraure resultats que evidencien l'efecte de la Gamificació en variables més enllà de la motivació. A més, emfatitzen la necessitat d'abordar la investigació des d'un enfocament qualitatiu i quantitatiu. La present tesi atén aquestes premisses, per això, amb la finalitat de donar resposta a la pregunta d'investigació i comprovar les diferents hipòtesis, es delimita un conjunt de variables qualitatives i quantitatives. Les més significatives són metodologia de Gamificació, competències específiques, competències transversals, motivació, rendiment acadèmic, rol docent i joc com a recurs didàctic. A més, s'utilitza un mètode mixt d'investigació que combina una anàlisi qualitativa, ratificat amb diferents anàlisis quantitatives per a aportar validesa ecològica a la investigació i major rigor a les conclusions. Entre les conclusions més rellevants destaquen la satisfacció dels subjectes participants cap a l'experiència gamificada, la millora de les competències específiques i el desenvolupament de diferents competències transversals. S'aconsegueix també un increment en la motivació i un bon rendiment acadèmic. Respecte al rol docent, la valoració és positiva, igual que el joc com a recurs didàctic. Les diferents anàlisis també aporten conclusions destacables relacionades amb el caràcter eclèctic de la metodologia, l'èxit en l'assistència, la capacitat d'atenció, el grau de participació, l'avaluació, l'atenció a la diversitat d'alumnat o la percepció del propi procés d'aprenentatge. A més, aquesta investigació acció considera els últims estudis en Gamificació i investigació educativa i respon a les demandes i reptes que aquests plantegen. D'aquesta manera, tracta d'aconseguir la projecció internacional a la qual s'aspira amb aquesta tesi doctoral i col·labora en la creació de coneixement empíric en el camp de la Gamificació. / [EN] The forthcoming doctoral thesis stems from the research question, is gamification an efficient method for learning the history of Spanish education in university training for future teachers? Four themes, which are explicit in the question itself, will give structure to this educational research. The first is the methodology of Gamification, which constitutes the grounds on which this investigation is based. The second is the history of Spanish education, the content delivered via a gamified experience. The third represents the university context in which the research takes place. Lastly, the fourth shows the demographic of those involved in the field study, alumni from Primary and Nursery School Teaching university degrees. This last theme is particularly relevant, as developing action research with future teachers is an integral part of mapping out quality university teaching (Paricio et al., 2019) and of binding research and transferability of pedagogic knowledge during the process. The most recent studies on Gamification advocate for extracting results that underline the effects of Gamification in variables beyond motivation. Furthermore, they emphasize the need to approach the research from a qualitative and quantitative point of view. Thereupon, the present doctoral thesis handles these propositions with the aim to answer the research question and prove different hypotheses, narrowing down a group of qualitative and quantitative variables. The most significant are Gamification methodology, specific competences, transversal competences, motivation, academic performance, the role of the lecturer and games as a teaching resource. In addition, a mixed research method is used which combines qualitative analysis, reinforced by different quantitative analyses in order to provide ecological validity to the study and more rigour to the conclusions. Among the most relevant conclusions, the following stand out: the satisfaction of the participating subjects towards the gamified experience, progress in specific competences, and the development of different transversal competences. Regarding the lecturer's role, the assessment is positive, as well as games as a teaching resource. The different analyses also provide noteworthy conclusions related to the eclectic nature of the methodology, attendance success, attention capacity, degree of participation, assessment, attention to student diversity or the perception of the process of learning itself. In addition, this action research examines the latest Gamification and educational research and answers the demands and challenges that they posit. In so doing, it attempts to achieve the international outreach to which this doctoral thesis aspires, and it assists in the creation of empiric knowledge in the field of Gamification. / Edo Agustín, E. (2021). La metodología de Gamificación para el aprendizaje de historia de la educación española: investigación acción en la formación universitaria de docentes [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/178971 / TESIS
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Propriétés biologiques du récepteur TLR3 dans les carcinomes des voies aérodigestives supérieures : contribution à l’oncogénèse et intérêt comme cible thérapeutique / Biological properties of the TLR3 receptor in Head and Neck carcinomas : oncogenic role and potential as a therapeutic target

Verillaud, Benjamin 06 February 2015 (has links)
Contexte. Les carcinomes des voies aérodigestives supérieures (VADS) arrivent en 6ème position parmi les cancers les plus fréquents au niveau mondial. La fonction du récepteur TLR3 dans les cellules de carcinomes des VADS est encore très mal comprise. Objectifs et méthodes. 1) Déterminer le niveau d’expression du récepteur TLR3 dans les lignées et les biopsies de carcinomes des VADS par western blot et par immunohistochimie. 2) Etudier le rôle de TLR3 dans la croissance tumorale de ces tumeurs, en utilisant notamment des lignées invalidées de façon conditionnelle pour TLR3. 3) Evaluer in vitro les effets cytotoxiques de ligands artificiels de TLR3 soit seuls, soit utilisés en combinaisons avec un inhibiteur d’IAP (inhibitor of apoptosis protein).Résultats. La protéine TLR3 est détectée à un niveau élevé en western blot dans les lignées de carcinomes des VADS étudiées, comparativement à un panel d’autres tumeurs épithéliales humaines. TLR3 est également constamment détecté en immunohistochimie dans les biopsies. TLR3 semble jouer un rôle dans la croissance tumorale des carcinomes des VADS : dans certaines conditions de culture (culture en hypoxie ou en milieu pauvre en SVF et en nutriments), la stimulation de TLR3 par un ligand exogène, le poly(A:U), favorise la croissance des cellules tumorales. Nous avons étudié l’effet de la stimulation de TLR3 sur le métabolisme glucidique dans ces mêmes cellules en utilisant un appareil de type Seahorse® qui mesure la consommation d’oxygène et la production de protons à partir de cellules cultivées en microplaques. Ces expériences montrent que la stimulation de TLR3 fait augmenter l’activité des voies du métabolisme cellulaire anaérobie (glycolyse extra-mitochondriale). Une étude métabolomique a mis en évidence des différences significatives dans le profil métabolique des cellules tumorales stimulées par le poly(A:U) comparativement aux cellules non traitées. Par ailleurs, nous avons montré que la stimulation de TLR3 permettait de détecter le facteur de transcription HIF1 en Western blot, même en conditions normoxiques. Sachant que des ARN libérés par des cellules en état de nécrose peuvent stimuler TLR3, il est tentant de penser que ce récepteur pourrait favoriser la survie des cellules malignes en zone hypoxique au voisinage de cellules nécrotiques. Néanmoins, l’expression de TLR3 représente aussi un facteur de vulnérabilité pour les cellules de carcinome des VADS : en effet les ligands artificiels de TLR3 utilisés en combinaison avec un inhibiteur d’IAP (Inhibitor of Apoptosis Protein) produisent des effets cytotoxiques sur les lignées de carcinomes des VADS étudiées. / Background. Head and Neck (HN) carcinomas are the 6th most frequent type of cancer worldwide. The role of the TLR3 receptor in HN carcinomas remains poorly understood.Objectives and Methods. 1) To assess the expression level of TLR3 in HN carcinoma cell lines and biopsies by Western blot and immunohistochemistry, respectively. 2) To study the role of TLR3 in tumour growth using specific cell lines with conditional knock-down of TLR3. 3). To assess in vitro the cytotoxic effects of artificial ligands of TLR3 used either alone or in combination with an IAP (inhibitor of apoptosis protein) inhibitor.Results. TLR3 protein was detected at a high level by Western blot analysis in HN carcinoma cell lines, by comparison with a panel of other human epithelial cancer cell lines. TLR3 was also consistently detected by immunohistochemistry in tumour biopsies. TLR3 seem to play a role in HN carcinoma cell growth: under certain culture conditions (hypoxic or low fetal calf serum/low nutrient culture conditions), TLR3 stimulation by a synthetic ligand, the poly(A:U), favours tumour cell growth. We investigated the effects of TLR3 stimulation on glucose metabolism using a Seahorse® analyzer, which measures the oxygen consumption and the proton production in living cells. Our results indicate that TLR3 stimulation induces an increase in anaerobic metabolism (extra-mitochondrial glycolysis). A metabolomic study revealed significant changes in the metabolic profile of cancer cells treated by poly(A:U) by comparison with untreated cells. We also showed that under TLR3 stimulation, HIF1 became detectable by Western blot analysis, even in normoxia. Given the fact that RNA fragments released by dying cells are able to trigger TLR3, one can assume that TLR3 might favour cancer cell survival in hypoxic areas located near the necrotic core of the tumour. However, TLR3 expression is also a factor of vulnerability for HN carcinoma cells: indeed, the combination of TLR3 artificial ligands with an IAP inhibitor has a strong cytotoxic effect on HN carcinoma cells in vitro.

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