977 resultados para Herpes simplex


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Tyypin 1 diabeteksen perinnöllinen alttius Suomessa - HLA-alueen ulkopuolisten alttiuslokusten IDDM2 ja IDDM9 rooli taudin periytymisessä HLA-alue, joka sijaitsee kromosomissa 6p21.3, vastaa noin puolesta perinnöllisestä alttiudesta sairastua tyypin 1 diabetekseen. Myös HLA-alueen ulkopuolisten lokusten on todettu liittyvän sairausalttiuteen. Näistä kolmen lokuksen on varmistettu olevan todellisia alttiuslokuksia ja lisäksi useiden muiden, vielä varmistamattomien lokusten, on todettu liittyvän sairausalttiuteen. Tässä tutkimuksessa 12:n HLA-alueen ulkopuolisen alttiuslokuksen kytkentä tyypin 1 diabetekseen tutkittiin käyttäen 107:aa suomalaista multiplex-perhettä. Jatkotutkimuksessa analysoitiin IDDM9-alueen kytkentä ja assosiaatio sairauteen laajennetuissa perhemateriaaleissa sekä IDDM2-alueen mahdollinen interaktio HLA-alueen kanssa sairauden muodostumisessa. Lisäksi suoritettiin IDDM2-alueen suojaavien haplotyyppien alatyypitys tarkoituksena tutkia eri haplotyyppien käyttökelpoisuutta sairastumisriskin tarkempaa ennustamista varten. Ensimmäisessä kytkentätutkimuksessa ei löytynyt koko genomin tasolla merkitsevää tai viitteellistä kytkentää tutkituista HLA-alueen ulkopuolisista lokuksista. Voimakkain havaittu nimellisen merkitsevyyden tavoittava kytkentä nähtiin IDDM9-alueen markkerilla D3S3576 (MLS=1.05). Tutkimuksessa ei kyetty varmistamaan tai sulkemaan pois aiempia kytkentähavaintoja tutkituilla lokuksilla, mutta IDDM9-alueen jatkotutkimuksessa havaittu voimakas kytkentä (MLS=3.4) ja merkitsevä assosiaatio (TDT p=0.0002) viittaa vahvasti siihen, että 3q21-alueella sijaitsee todellinen tyypin 1 diabeteksen alttiusgeeni, jolloin alueen kattava assosiaatiotutkimus olisi perusteltu jatkotoimenpide. Sairauteen altistava IDDM2-alueen MspI-2221 genotyyppi CC oli nimellisesti yleisempi matalan tai kohtalaisen HLA-sairastumisriskin diabeetikoilla, verrattuna korkean HLA-riskin potilaisiin (p=0.05). Myös genotyyppijakauman vertailu osoitti merkitsevää eroa ryhmien välillä (p=0.01). VNTR-haplotyyppitutkimus osoitti, että IIIA/IIIA-homotsygootin sairaudelta suojaava vaikutus on merkitsevästi voimakkaampi kuin muiden luokka III:n genotyypeillä. Nämä tulokset viittaavat IDDM2-HLA -vuorovaikutukseen sekä siihen että IDDM2-alueen haplotyyppien välillä esiintyy etiologista heterogeniaa. Tämän johdosta IDDM2-alueen haplotyyppien tarkempi määrittäminen voisi tehostaa tyypin 1 diabeteksen riskiarviointia.

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Le cancer de la vessie est le deuxième cancer urologique le plus fréquent dans le monde. La plupart des patients (75%) sont initialement diagnostiqués avec un cancer non musculo- invasif. Après résection trans-urétrale, ie traitement standard pour ce type de lésion chez les patients présentant un risque important de récidive/progression consiste en une série d'instillations intravésicales du Bacille de Calmette-Guerin (i.e. le vaccin BCG). Cependant cette "BCG thérapie" est associée à des effets secondaires non négligeables et s'avère inefficace dans 30% des cas, des limitations donc importantes qui soulignent la nécessité de développer des stratégies thérapeutiques alternatives. L'utilisation d'antigènes associés aux tumeurs (TAA) comme vaccin, combinée à une application locale d'immunostimulants sur le site tumoral, est une approche prometteuse en vue de maximiser les réponses immunitaires anti-tumorales localement. Nous montrons que la bactérie vivante atténuée Ty21a, issue du vaccin Vivotif® contre la fièvre typhoïde, peut être utilisée comme immunostimulant intravésical (IVES), mais ce uniquement dans le cas où la bactérie est en phase exponentielle de croissance (Vivotif exp). En effet, l'instillation IVES de Vivotif exp à la suite d'une vaccination par un TAA, un antigène mineur d'histocompatibilité mâle H-Y (Uty), permet d'augmenter de 15 fois le nombre de cellules T CD8 totales et spécifiques de l'antigène dans la vessie. Le recrutement des cellules T est TLR4-dépendent, ce qui suggère un rôle des lipopolysaccharides du Vivotif exp. Par ailleurs, en comparaison avec le contenu bactérien de la capsule de Vivotif, les bactéries en phase exponentielle de croissance permettent également une augmentation préférentielle des chemokines C5/C5a, CXCL1, CXCL2 et CXCL5 dans la vessie, mais pas du nombre de cellules T exprimant les récepteurs apparentés (C5aR et CXCR2). De plus, combiner la vaccination Uty avec le Vivotif exp en IVES permet d'améliorer la survie des souris présentant une tumeur orthotopique de la vessie exprimant l'antigène Uty (lignée tumorale murine MB49). Puisque pour certains cancers, aucun TAA - du moins exprimé à tous les stades tumoraux - n'est identifié, il est nécessaire de développer d'autres approches non vaccinales. Dans une deuxième partie de ce travail de thèse, nous avons donc investigué deux stratégies permettant d'induire une destruction des cellules tumorales, la thérapie génique par gène de suicide, d'une part, et la thérapie photodynamique dans le proche infrarouge (NIR-PDT), d'autre part. Pour appliquer ces thérapies, nous avons utilisé comme vecteur sûr et non toxique une forme non réplicative du virus du « Human Papillomavirus » (HPV) capable de "pseudo-infecter" préférentiellement les souris présentant des tumeurs vésicales (MB49). L'utilisation de pseudovirions (PsV) HPV portant comme gène suicide la thymidine kinase, une enzyme du virus de l'herpès simplex, suivi d'un traitement par la prodrogue Ganciclovir, permet de tuer 90% des cellules MB49 in-vitro ainsi que de ralentir significativement le développement des tumeurs vésicales in-vivo. Par ailleurs, l'emploi de particules pseudo- virales HPV couplées à la phtalocyanine IR700, un pigment photosensible présentant un pouvoir cytotoxique une fois activé, permet de tuer, après application d'une lumière dans le proche infrarouge, quasi 100% des cellules MB49 in-vitro et, plus important, de régresser des tumeurs in-vivo. De façon générale, ce travail de thèse présente des approches thérapeutiques innovantes et prometteuses pour le traitement des patients avec un cancer non musculo-invasif de la vessie. -- Bladder cancer is the second most common urological malignancy in the world. At initial diagnosis, non-muscle invasive bladder cancer (NMIBC) accounts for 75% of bladder cancer. The standard of care of NMIBC consists of intravesical (IVES) treatments with Bacillus- Calmette-Guerin (BCG) following transurethral resections of the lesions. However, repeated BCG treatments are associated with significant side effects and treatment failure may occur in 30% of the cases, underlying the necessity of alternative therapeutic strategies. The use of tumor-associated antigens (TAA) as vaccines followed by the local application of immunostimulants where the tumor resides is a promising approach to increase anti-tumor immune responses locally. We show that live attenuated Ty21a bacteria used from the vivotif® vaccine against typhoid fever can efficiently be used as IVES immunostimulant, only if bacteria are grown to exponential phase (Vivotif exp). In this condition, IVES immunostimulation after TAA vaccination with a minor histocompatibility male antigen HY (Uty) resulted in more than 15-fold increase of both vaccine-specific and total CD8-T cells in the bladder. T cell recruitment was mediated by TLR-4 suggesting that it was mainly mediated by lipopolysaccharides of Vivotif exp. In addition, these bacteria, as compared to the bacterial content of the vivotif capsule preferentially increased C5/C5a, CXCL1, CXCL2 and CXCL5 chemokines, but not the numbers of T cells expressing the cognate receptors (C5aR and CXCR2). Combination of IVES Vivotif exp with Uty vaccination improved survival of mice with pre-established orthotopic Uty-expressing MB49 murine bladder tumors, as compared to vaccination alone. As known TAA are not identified in all cancers, or not expressed in all stages of the tumor, we further investigated two potent approaches able of initiating tumor-cell destruction, suicide-gene therapy and near-infrared (NIR) photodynamic therapy (PDT). Towards a safe and non-toxic application of these therapies, we used Human Papillomavirus (HPV) replication-defective vectors that were able to preferentially pseudo-infect MB49-tumor bearing mice. HPV pseudovirions (PsV) carrying the Herpex-Simplex virus thymidine kinase suicide-gene followed by treatment with the prodrug Ganciclovir resulted in 90% of MB49 cell-death in-vitro and was able to significantly reduce bladder tumor growth in-vivo. Furthermore, HPV virus-like particles coupled to a NIR phtalocyanine dye, IR700 in combination with specific NIR light led to almost 100% of MB49 cell-death in-vitro and more interestingly, to bladder tumors shrinkage in-vivo. Overall, in this thesis, we offer promising therapeutic approaches for application in NMIBC patients.

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Con esta revisión se pretende remarcar al odontoestomatólogo los aspectos clínicos que con mayor frecuencia se asocian a la infección producida por el VIH. Entre ellos cabe resaltar las infecciones producidas por virus (herpes simple, herpes varicela-zoster, citomegalovirus. papilomavirus), hongos (sobre todo candidiasis) y bacterias (caries y patología periodontal); la patología tumoral asociada (sarcoma de Kaposi, linfoma no Hodgkin, carcinomas); así como otras manifestaciones patológicas que tienen su asiento en el territorio del aparato estomatognático (ulceraciones atípicas, alteraciones neurológicas, patología glandular. etc.). No puede concluirse el trabajo sin recordar la importancia que tiene seguir un protocolo en la atención odontológica de estos pacientes seropositivos, que debería hacerse extensivo al resto de nuestros pacientes.

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Leukemiaa sairastavien lasten kuumeiset infektiot, erityisesti respiratoriset virusinfektiot Tausta: Hengitysteiden virusinfektiot ovat lasten tavallisimpia sairauksia. Infektiota aiheuttava virus voidaan uusilla menetelmillä löytää lähes kaikissa tapauksissa. Leukemiaa sairastavilla lapsilla on perustaudin ja leukemian hoitojen takia tavallista suurempi infektioalttius, ja kuumeilu on tavallista leukemiahoidon aikana. Suurin osa syöpähoidon aikaisten kuumejaksojen syistä jää kuitenkin selvittämättä. Tavoitteet: Prospektiivisen 5 vuotta kestäneen monikeskustutkimuksen tavoitteena oli etsiä uusimmilla mikrobiologisilla menetelmillä leukemiaa sairastavien lasten kuumeen syy. Tätä varten tutkittiin 16 virusta virusviljelyllä, antigeeniosoituksella ja nukleiinihappo-osoituksella. Näytteitä otettiin nenästä, ulosteesta, virtsasta ja verestä. Lisäksi tutkittiin MxA-proteiinin kykyä osoittaa virusinfektio syöpälapsella. Tulokset: Tutkimuksen aikana analysoitiin 138 kuumejaksoa 51 leukemialapsella. Kokonaisseuranta-aika oli 1.5 vuotta/lapsi. Kuumejaksojen ilmaantuvuus oli 2.1 jaksoa potilasta kohden suhteutettuna vuoden riskiaikaan. Hengistysteiden virusinfektio voitiin osoittaa 82 kuumejaksossa (59%). Kaksi tai useampi virus löydettiin 12 %:ssa kuumejaksoista. Tavallisimmat virukset olivat rhinovirus (22 %), respiratory syncytial virus eli RS-virus (11 %), human herpes virus 6 (7 %), human bocavirus (5 %), sytomegalovirus (5 %), parainfluenssavirukset (5 %) ja influenssa A -virus (4 %). Kahdelle potilaalle kehittyi pneumonia, muilla oireet olivat lievät. Veriviljely oli positiivinen 19 kuumejaksossa (14 %), ja puolessa tapauksista löydettiin samanaikaisesti respiratorinen virus. MxA proteini ilmeni veren lymfosyyteissä useimmilla virusinfektioon sairastuneilla syöpälapsilla. Päätelmät: Kuumeiset respiratoriset virusinfektiot ovat tavallisia leukemiaa sairastavilla lapsilla. Infektion oireet ovat tavallisesti vähäiset, mutta pienelle osalle voi kehittyä veriviljelypositiivinen sepsis tai pneumonia. Kuumeen syy jäi selvittämättä vain harvoissa tapauksissa.

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Within the special geometry of the simplex, the sample space of compositional data, compositional orthonormal coordinates allow the application of any multivariate statistical approach. The search for meaningful coordinates has suggested balances (between two groups of parts)—based on a sequential binary partition of a D-part composition—and a representation in form of a CoDa-dendrogram. Projected samples are represented in a dendrogram-like graph showing: (a) the way of grouping parts; (b) the explanatory role of subcompositions generated in the partition process; (c) the decomposition of the variance; (d) the center and quantiles of each balance. The representation is useful for the interpretation of balances and to describe the sample in a single diagram independently of the number of parts. Also, samples of two or more populations, as well as several samples from the same population, can be represented in the same graph, as long as they have the same parts registered. The approach is illustrated with an example of food consumption in Europe

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Protocolos terapeuticos. Infección prenatal. Riesgo de infección prenatal. La infección prenatal requiere un alto índice de sospecha, ya que no siempre, los antecedentes se hallan presentes bien porque faltan o bien porque hayan pasado desapercibidos. Dentro del concepto de infección prenatal se encuentran las englobadas en el acrónimo Torches (toxoplasmosis, rubeola, citomegalovirosis, herpes o sífilis) )...

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The identification of cancer-specific enzymatic activities that can be therapeutically targeted is key to the development of suitable anti-cancer drugs. Primary effusion lymphoma (PEL) is a rare and incurable malignancy that can occur in immunodeficient patients as a consequence of latent infection of B-cells with Kaposi's sarcoma-associated herpesvirus, KSHV (also known as human herpesvirus-8, HHV8). Malignant growth of KSHV-infected B cells requires the constitutive activity of the transcription factor NF-KB, which controls expression of viral genes required for maintenance of viral latency and suppression of the viral lytic program. Here we identify the protease mucosa-associated lymphoid tissue transformation protein 1 (MALTI), a key driver of NF-KB activation in lymphocytes, as an essential component in KSHV-dependent NF-KB activation and growth of latently infected PEL cell lines. Inhibition of the MALTI protease activity induced a switch from the latent to the lytic stage of viral infection, and led to reduced growth and survival of PEL cell lines in vitro and in a xenograft model. These results demonstrate a key role for the proteolytic activity of MALTI in PEL, and provide a rationale for the pharmacological targeting of MALTI in PEL therapy. -- L'identification d'activités enzymatiques propre au cancer est clé dans le développement des nouvaux médicaments anti-cancer. Le lymphome primitif des séreuses est un lymphome rare et incurable qui peut se developer chez les patients immunodéficients. Il est la conséquence d'une infection latente des cellules B, dûe à l'herpes virus 8, plus connu comme herpes virus associé au sarcome de Kaposi (KSHV). La croissance maligne des cellules B infecteés par KSHV requière l'activité constitutive du facteur de transcription NF-KB qui contrôle l'expression des genes viraux requis pour la maintenance latente et la suppression du programme de lyse du virus. Avec cette étude, nous avons identifié la protease MALTI comme un composant essentiel dans l'activation de NF-KB dans les cellules B du lymphome primitif des séreuses. L'inhibition de l'activité de la protéase MALTI induit un virement de la phase latente à la phase lytique du KSHV et conduit à une reduction de la viabilité des cellules tumorales in vitro et dans un modèle de xénogreffe. Ces résultats démontrent un rôle clé pour l'activité protéolytique de MALTI dans le développement du lymphome primitif des séreuses et soutiennent l'idée que MALTI pourrait être une cible pharmacologique dans la thérapie de cette forme rare du lymphome.

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Tumor necrosis factor (TNF)/TNF receptor (TNFR) superfamily members play essential roles in the development of the different phases of the immune response. Mouse LIGHT (TNFSF14) is a type II transmembrane protein with a C-terminus extracellular TNF homology domain (THD) that assembles in homotrimers and regulates the course of the immune responses by signaling through 2 receptors, the herpes virus entry mediator (HVEM, TNFSFR14) and the lymphotoxin β receptor (LTβR, TNFSFR3). LIGHT is a membrane-bound protein transiently expressed on activated T cells, natural killer (NK) cells and immature dendritic cells that can be proteolytically cleaved by a metalloprotease and released to the extracellular milieu. The immunotherapeutic potential of LIGHT blockade was evaluated in vivo. Administration of an antagonist of LIGHT interaction with its receptors attenuated the course of graft-versus-host reaction and recapitulated the reduced cytotoxic activity of LIGHT-deficient T cells adoptively transferred into non-irradiated semiallogeneic recipients. The lack of LIGHT expression on donor T cells or blockade of LIGHT interaction with its receptors slowed down the rate of T cell proliferation and decreased the frequency of precursor alloreactive T cells, retarding T cell differentiation toward effector T cells. The blockade of LIGHT/LTβR/HVEM pathway was associated with delayed downregulation of interleukin-7Rα and delayed upregulation of inducible costimulatory molecule expression on donor alloreactive CD8 T cells that are typical features of impaired T cell differentiation. These results expose the relevance of LIGHT/LTβR/HVEM interaction for the potential therapeutic control of the allogeneic immune responses mediated by alloreactive CD8 T cells that can contribute to prolong allograft survival.

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This work illustrates the modeling procedure for a solvent mixture using the simplex- centroid approach. The selected experiment was the optimization of the peak current observed in the direct determination of nickel by anodic stripping voltammetry (ASV) in a solvent mixture composed of N,N-dimethylformamide, ethanol and water. The text is presented in a tutorial way, showing in detail the several steps which must be followed in such a process. Since not all possible mixtures lead to a measurable instrumental response, pseudocomponents had to be used to rescale the experimental design. This also allows to show how to apply this tool, usually troublesome for non-specialists in mixture modeling procedures.

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Phenomena with a constrained sample space appear frequently in practice. This is the case e.g. with strictly positive data, or with compositional data, like percentages or proportions. If the natural measure of difference is not the absolute one, simple algebraic properties show that it is more convenient to work with a geometry different from the usual Euclidean geometry in real space, and with a measure different from the usual Lebesgue measure, leading to alternative models which better fit the phenomenon under study. The general approach is presented and illustrated using the normal distribution, both on the positive real line and on the D-part simplex. The original ideas of McAlister in his introduction to the lognormal distribution in 1879, are recovered and updated

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Compositional data (concentrations) are common in geosciences. Neglecting its character mey lead to erroneous conclusions. Spurious correlation (K. Pearson, 1897) has disastrous consequences. On the basis of the pioneering work by J. Aitchison in the 1980s, a methodology free of these drawbacks is now available. The geometry of the símplex allows the representation of compositions using orthogonal co-ordinares, to which usual statistical methods can be applied, thus facilating computation ans analysis. The use of (log) ratios precludes the interpretation of single concentrations disregarding their relative character. A hydro-chemical data set is used to illustrate the point

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A neural network procedure to solve inverse chemical kinetic problems is discussed in this work. Rate constants are calculated from the product concentration of an irreversible consecutive reaction: the hydrogenation of Citral molecule, a process with industrial interest. Simulated and experimental data are considered. Errors in the simulated data, up to 7% in the concentrations, were assumed to investigate the robustness of the inverse procedure. Also, the proposed method is compared with two common methods in nonlinear analysis; the Simplex and Levenberg-Marquardt approaches. In all situations investigated, the neural network approach was numerically stable and robust with respect to deviations in the initial conditions or experimental noises.

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This work propose a recursive neural network to solve inverse equilibrium problem. The acidity constants of 7-epiclusianone in ethanol-water binary mixtures were determined from multiwavelength spectrophotmetric data. A linear relationship between acidity constants and the %w/v of ethanol in the solvent mixture was observed. The proposed method efficiency is compared with the Simplex method, commonly used in nonlinear optimization techniques. The neural network method is simple, numerically stable and has a broad range of applicability.

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Methane combustion was studied by the Westbrook and Dryer model. This well-established simplified mechanism is very useful in combustion science, for computational effort can be notably reduced. In the inversion procedure to be studied, rate constants are obtained from [CO] concentration data. However, when inherent experimental errors in chemical concentrations are considered, an ill-conditioned inverse problem must be solved for which appropriate mathematical algorithms are needed. A recurrent neural network was chosen due to its numerical stability and robustness. The proposed methodology was compared against Simplex and Levenberg-Marquardt, the most used methods for optimization problems.

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In this research work the effects of four solvents and their mixtures on the extraction of chlorogenic acids, caffeine and trigonelline in crude extracts of four coffee cultivars, traditional red bourbon, IAPAR59, IPR101 and IPR108 cultivars, were investigated by UV spectrophotometry and UV spectra obtained from RP-HPLC-DAD. The experimental results and the principal component analysis of UV spectra showed that the effect of solvent extraction of the metabolites does not depend on cultivars, because the spectral characteristics are similar, but the concentrations are different. The UV and UV-DAD spectra for four simplex centroid design mixtures were also similar but the concentrations of caffeine, trigonelline and the chlorogenic acids are different and depend on the solvent used in the extraction.