909 resultados para Hybridation in situ en fluorescence (FISH)


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Die Mesostruktur von Werkstoffen wie Faserverbundwerkstoffen und Schaumstoffen beeinflusst deren mechanisches Verhalten wesentlich. Die inneren Strukturen des Werkstoffes müssen in die Analyse des Verformungs- und Versagensverhaltens einbezogen werden. Die Röntgenanalyse, insbesondere die Röntgen-Computertomographie (Röntgen-CT) ermöglicht eine zerstörungsfreie 3-dimensionale (3-d) Visualisierungund Charakterisierung innerer Strukturen. Für die Untersuchung des Einflusses der Mesostruktur eines Polymethacrymlid-Hartschaumstoffes auf das mechanische Verhalten speziell unter zugbelastung sollte eine speziell vom Fraunhofer-Institut für Werkstoffmechanik in Halle entwickelte In-situ-Verformungseinrichtung erprobt werden. Die Anlage wurde speziell für den Zugversuch optimiert. Es folgten mechanische Experimente, die mit den 3d-Bilddaten der Zellstruktur des Schaumstoffes korrelieren. Die ermittelten Bilddaten werden mit Hilfe einer Bildanalysesoftware ausgewertet und Rückschlüsse auf Verformungs- und Versagensverhalten grtroffen.

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Aquest article tracta el tema del “ne bis in idem” com a garantia processal penal del sistema interamericà de protecció dels drets humans. Tot fent referència als casos portats a la Cort Inteamericana de Drets Humans, s’hi presenten algunes consideracions que s’han tingut en compte a l’hora de flexibilitzar-ne el principi. Aquesta garantia es compara amb el sistema del “double jeopardy” de la common law. Així mateix, es compara també amb altres sistemes de protecció dels drets humans, com l’europeu, el del Tribunal Penal Internacional i el del Pacte de Drets Civils i Polítics de les Nacions Unides. Per concloure, es destaca la importància de l’harmonització de les garanties del procés penal en relació amb la discussió de conflictes jurisdiccionals. Aquest text és fruit de les reflexions debatudes Durand el curs de postgrau de la Facultat de Dret de la Universitat de São Paulo, “As Garantias do Processo Penal no Sistema Interamericano de Direitos Humanos”, 2008.

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Este artículo trata el tema del ne bis in idem como garantía procesal penal dentro del sistema interamericano de protección de los derechos humanos. Haciendo referencia a los casos llevados ante la Corte Interamericana de Derechos Humanos, se presentan algunas reflexiones que fueron tomadas en consideración para la flexibilización del principio. Esta garantía se compara con el sistema del “double jeopardy” de la common law. Asimismo, se compara también con otros sistemas de protección de los derechos humanos, como el europeo, el del Tribunal Penal Internacional y el del Pacto de Derechos Civiles y Políticos de las Naciones Unidas. Finalmente, se destaca la importancia de la armonización de garantías del proceso penal en la discusión de conflictos jurisdiccionales. Este texto es producto de las reflexiones debatidas en el curso de postgrado de la Facultad de Derecho de la Universidad de São Paulo, “As Garantias do Processo Penal no Sistema Interamericano de Direitos Humanos”, 2008.

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Effector T lymphocytes are the progeny of a limited number of antigen-specific precursor cells and it has been estimated that clonotypic human T cells may expand million fold on their way reaching high cell numbers that are sufficient for immune protection. Moreover, memory T cell responses are characterized by repetitive expansion of antigen-specific T cell clonotypes, and limitations in the proliferative capacity could lead to immune senescence. Because telomeres progressively shorten as a function of cell division, telomere length is a powerful indicator of the replicative in vivo history of human T lymphocytes. In this review, we summarize observations made over the last decade on telomere length dynamics of well-defined T cell populations derived from healthy donors and patients with infectious disease or cancer. We focus on T cell differentiation, T cell ageing, and natural and vaccine induced immune responses. We also discuss the scientific evidence for in vivo replicative senescence of antigen-specific T cells, and evaluate the available methods for measuring telomere lengths and telomerase activity, and their potential and limitations to increase our understanding of T cell physiology.

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Formation of a membrane-associated replication complex, composed of viral proteins, replicating RNA, altered cellular membranes, and other host factors, is a hallmark of all positive-strand RNA viruses. In the case of HCV, RNA replication takes place in a likely endoplasmic reticulum-derived membrane alteration referred to as the "membranous web." In vitro transcription-translation, membrane extraction and flotation analyses, immunofluorescence microscopy, fluorescent in situ hybridization, and RNA metabolic labeling followed by confocal laser scanning microscopy have yielded insights into the structure and function of the HCV replication complex. We describe these techniques and highlight selected results.

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Projecte de recerca elaborat a partir d’una estada a la Stanford University, EEUU, entre 2007 i 2009. El present projecte es basa 1) en la síntesi de cadenes d'ARN dirigides a la inhibició de l'expressió gènica per un mecanisme d'ARN d'interferència (siRNAs o short interefering RNAs) i 2) en l'avaluació de l'activitat in vitro d'aquests oligonucleòtids en cultius cel•lulars. Concretament, la meva recerca ha estat enfocada principalment a l'estudi de cadenes de siRNA modificades amb nucleobases 5-metil i 5-propinil pirimidíniques. Es tractava d'avaluar l'efecte que exerceixen els factors estèrics en el major groove (solc major) dels siRNAs sobre la seva activitat biològica. En aquest sentit, he dut aterme síntesi de fosforamidits de nucleòsis pirimidínics modificats a la posició C-5 de la nucleobase. A continuació he incorporat aquestes unitats nucleosídiques en cadenes d'ARN emprant un sintetitzador d’ADN/ARN i he estudiat l'estabilitat dels corresponents dúplexs d'ARN mitjançant experiments de desnaturalització tèrmica. Finalment he dut a terme experiments d'inhibició de l'expressió gènica en cèl.lules HeLa per tal d'avaluar l'activitat biològia d'aquests siRNAs modificats. Els resultats d'aquests estudis han posat de manifest que la presència de grups voluminosos com el propinil a l'extrem 5' del dúplex de siRNA (definit per la cadena guia o antisense) influeix de forma molt negativa en la seva activitat biològica. En canvi, grups menys voluminosos com el metil hi influeixen positivament, de manera que algunes de les cadenes sintetitzades han resultat ser més actives que els corresponents siRNAs naturals (wild type siRNAs). A més, aquest tipus de modificació contribueix positivament en l'estabilitat de cadenes de siRNA en sèrum humà. Aquest treball ha estat publicat (Terrazas, M.; Kool, E.T. "Major Groove Modifications Improve siRNA Stability and Biological Activity" Nucleic Acids Res. 2009, in press).

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Ductal carcinoma in situ (DCIS), accounting for 15-25% of all breast cancers, is frequently diagnosed by mammographic examination. This heterogeneous disease requires a rigorous local treatment based, in about two-third of cases, on conservative surgery and radiotherapy. DCIS are currently classified on the basis of nuclear grade. Most lesions, and especially high nuclear grade DCIS, are limited to one quadrant. Micropapillary DCIS are likely to be of larger size/extent and thus a conservative approach is often difficult. A careful pathological examination of an oriented excisional biopsy is a pre-requisite for optimal therapy.

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Islet-brain 1 (IB1), a regulator of the pancreatic beta-cell function in the rat, is homologous to JIP-1, a murine inhibitor of c-Jun amino-terminal kinase (JNK). Whether IB1 and JIP-1 are present in humans was not known. We report the sequence of the 2133-bp human IB1 cDNA, the expression, structure, and fine-mapping of the human IB1 gene, and the characterization of an IB1 pseudogene. Human IB1 is 94% identical to rat IB1. The tissue-specific expression of IB1 in human is similar to that observed in rodent. The IB1 gene contains 12 exons and maps to chromosome 11 (11p11.2-p12), a region that is deleted in DEFECT-11 syndrome. Apart from an IB1 pseudogene on chromosome 17 (17q21), no additional IB1-related gene was found in the human genome. Our data indicate that the sequence and expression pattern of IB1 are highly conserved between rodent and human and provide the necessary tools to investigate whether IB1 is involved in human diseases.

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Translocations are known to affect the expression of genes at the breakpoints and, in the case of unbalanced translocations, alter the gene copy number. However, a comprehensive understanding of the functional impact of this class of variation is lacking. Here, we have studied the effect of balanced chromosomal rearrangements on gene expression by comparing the transcriptomes of cell lines from controls and individuals with the t(11;22)(q23;q11) translocation. The number of differentially expressed transcripts between translocation-carrying and control cohorts is significantly higher than that observed between control samples alone, suggesting that balanced rearrangements have a greater effect on gene expression than normal variation. Many of the affected genes are located along the length of the derived chromosome 11. We show that this chromosome is concomitantly altered in its spatial organization, occupying a more central position in the nucleus than its nonrearranged counterpart. Derivative 22-mapping chromosome 22 genes, on the other hand, remain in their usual environment. Our results are consistent with recent studies that experimentally altered nuclear organization, and indicated that nuclear position plays a functional role in regulating the expression of some genes in mammalian cells. Our study suggests that chromosomal translocations can result in hitherto unforeseen, large-scale changes in gene expression that are the consequence of alterations in normal chromosome territory positioning. This has consequences for the patterns of gene expression change seen during tumorigenesis-associated genome instability and during the karyotype changes that lead to speciation.

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BACKGROUND Taxanes are among the most active drugs for the treatment of metastatic breast cancer, and, as a consequence, they have also been studied in the adjuvant setting. METHODS After breast cancer surgery, women with lymph node-positive disease were randomly assigned to treatment with fluorouracil, epirubicin, and cyclophosphamide (FEC) or with FEC followed by weekly paclitaxel (FEC-P). The primary endpoint of study-5-year disease-free survival (DFS)-was assessed by Kaplan-Meier analysis. Secondary endpoints included overall survival and analysis of the prognostic and predictive value of clinical and molecular (hormone receptors by immunohistochemistry and HER2 by fluorescence in situ hybridization) markers. Associations and interactions were assessed with a multivariable Cox proportional hazards model for DFS for the following covariates: age, menopausal status, tumor size, lymph node status, type of chemotherapy, tumor size, positive lymph nodes, HER2 status, and hormone receptor status. All statistical tests were two-sided. RESULTS Among the 1246 eligible patients, estimated rates of DFS at 5 years were 78.5% in the FEC-P arm and 72.1% in the FEC arm (difference = 6.4%, 95% confidence interval [CI] = 1.6% to 11.2%; P = .006). FEC-P treatment was associated with a 23% reduction in the risk of relapse compared with FEC treatment (146 relapses in the 614 patients in the FEC-P arm vs 193 relapses in the 632 patients in the FEC arm, hazard ratio [HR] = 0.77, 95% CI = 0.62 to 0.95; P = .022) and a 22% reduction in the risk of death (73 and 95 deaths, respectively, HR = 0.78, 95% CI = 0.57 to 1.06; P = .110). Among the 928 patients for whom tumor samples were centrally analyzed, type of chemotherapy (FEC vs FEC-P) (P = .017), number of involved axillary lymph nodes (P < .001), tumor size (P = .020), hormone receptor status (P = .004), and HER2 status (P = .006) were all associated with DFS. We found no statistically significant interaction between HER2 status and paclitaxel treatment or between hormone receptor status and paclitaxel treatment. CONCLUSIONS Among patients with operable breast cancer, FEC-P treatment statistically significantly reduced the risk of relapse compared with FEC as adjuvant therapy.

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INTRODUCTION The relationship between circulating prolactin and invasive breast cancer has been investigated previously, but the association between prolactin levels and in situ breast cancer risk has received less attention. METHODS We analysed the relationship between pre-diagnostic prolactin levels and the risk of in situ breast cancer overall, and by menopausal status and use of postmenopausal hormone therapy (HT) at blood donation. Conditional logistic regression was used to assess this association in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, including 307 in situ breast cancer cases and their matched control subjects. RESULTS We found a significant positive association between higher circulating prolactin levels and risk of in situ breast cancer among all women [pre-and postmenopausal combined, ORlog2 = 1.35 (95%CI 1.04-1.76), Ptrend = 0.03]. No statistically significant heterogeneity was found between prolactin levels and in situ cancer risk by menopausal status (Phet = 0.98) or baseline HT use (Phet = 0.20), although the observed association was more pronounced among postmenopausal women using HT compared to non-users (Ptrend = 0.06 vs Ptrend = 0.35). In subgroup analyses, the observed positive association was strongest in women diagnosed with in situ breast tumors <4 years compared to ≥4 years after blood donation (Ptrend = 0.01 vs Ptrend = 0.63; Phet = 0.04) and among nulliparous women compared to parous women (Ptrend = 0.03 vs Ptrend = 0.15; Phet = 0.07). CONCLUSIONS Our data extends prior research linking prolactin and invasive breast cancer to the outcome of in situ breast tumours and shows that higher circulating prolactin is associated with increased risk of in situ breast cancer.

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Le motif de la ruse est une constante de l'imaginaire africain et ses figures, souvent animales dans les contes, attestent de la valeur symbolique de cet art du stratagème. Avec la complicité du roman d'H. Bâ, L'étrange destin de Wangrin, et celui d'A. Kourouma, Monnè, outrages et défis, nous allons montrer que la ruse et le rusé ont subi une métamorphose en devenant des pratiques textuelles. La ruse littéraire donne voix à « l'autre » et la langue construite sous ce signe-là est le lieu d'une prise de pouvoir, celle de sa propre énonciation.

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Ihmisen papilloomavirus (Human papillomavirus HPV) aiheuttaa yleisen sukupuoliteitse leviävän tartuntataudin. Virusinfektiolla on todettu olevan yhteys kohdunkaulan syöpään ja on siksi tärkeä tutkimuskohde. Kätilöopiston sairaalan patologian laboratoriossa tutkitaan HPV:ta Hybrid Capture 2 -menetelmällä, joka antaa tuloksen kvantitatiivisena. Tulos on joko positiivinen tai negatiivinen korkean riskin HPV-genotyypeille. Tutkimuskohteena oli ihmisen papilloomavirusta määrittävä in situ -hybridisaatiomenetelmä, joka on tarkoitus ottaa käyttöön Kätilöopiston sairaalan patologian laboratorioon. Näytemateriaali kerättiin HUSLAB:n Qpati-tietokannasta. 40 potilastapausta valittiin, joista kymmenen potilastapausta kuuluu kondyloma planum-, kymmenen dysplasia levis-, kymmenen dysplasia moderata- ja viimeiset kymmenen dysplasia gravis -luokitukseen. Näytteet oli valettu parafiiniin, joista leikkattiin uudet näytelasit. Näistä tehtiin HPV in situ -hybridisaatio-, p16INK4a-, Ki67- ja hematoksyliini-eosiinivärjäykset. HPV ISH:n tuloksia verrattiin negatiivisten ja positiivisten kontrollien antamiin tuloksiin. Lisäksi tutkittiin proteiinien p16INK4a ja Ki67 vastaavuutta HPV ISH:n antamiin tuloksiin. Ki67 ja p16INK4a ovat merkkiaineita, joita havaitaan HPV:n aiheuttamissa dysplastisissa muutoksissa. HE-värjäyksen avulla tarkistettiin diagnoosiluokat. HPV in situ -hybridisaationäytteissä esiintyi HPV DNA-viruskopioita 82,5 %:ssa (33/40). Näytteistä negatiivisen tuloksen antoi 12,5 % (5/40) ja 5 % (2/40) niistä ei voitu tulkita. Immunohistokemialliset värjäykset antoivat keskenään yhteneväisiä tuloksia. Tulokset olivat yhteneviä myös HPV in situ -hybridisaation antamiin tuloksiin. Tulokset olivat luotettavia, koska negatiivinen kontrolli antoi negatiivisen ja positiivinen kontrolli positiivisen tuloksen. Hematoksyliini-eosiinivärjäyksellä tarkistetuista diagnoosiluokista 20 prosenttia (8/40) oli muuttunut. Tulokset olivat luotettavia, joten voidaan todeta, että in situ -hybridisaatiomenetelmä voidaan ottaa käyttöön Kätilöopiston sairaalan patologian laboratoriolle.

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Infantile spasms (IS) is the most severe and common form of epilepsy occurring in the first year of life. At least half of IS cases are idiopathic in origin, with others presumed to arise because of brain insult or malformation. Here, we identify a locus for IS by high-resolution mapping of 7q11.23-q21.1 interstitial deletions in patients. The breakpoints delineate a 500 kb interval within the MAGI2 gene (1.4 Mb in size) that is hemizygously disrupted in 15 of 16 participants with IS or childhood epilepsy, but remains intact in 11 of 12 participants with no seizure history. MAGI2 encodes the synaptic scaffolding protein membrane-associated guanylate kinase inverted-2 that interacts with Stargazin, a protein also associated with epilepsy in the stargazer mouse.

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The combination of multiple exostoses (EXT) and enlarged parietal foramina (foramina parietalia permagna, FPP) represent the main features of the proximal 11p deletion syndrome (P11pDS), a contiguous gene syndrome (MIM 601224) caused by an interstitial deletion on the short arm of chromosome 11. Here we present clinical aspects of two new P11pDS patients and the clinical follow-up of one patient reported in the original paper describing this syndrome. Recognised clinical signs include EXT, FPP, mental retardation, facial asymmetry, asymmetric calcification of coronary sutures, defective vision (severe myopia, nystagmus, strabismus), skeletal anomalies (small hands and feet, tapering fingers), heart defect, and anal stenosis. In addition fluorescence in situ hybridisation and molecular analysis were performed to gain further insight in potential candidate genes involved in P11pDS.