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Etude de la déstabilisation des structures protéique et chromatinienne des centromères par la protéine ICP0 du virus Herpes Simplex de Type 1Gross, Sylvain 01 December 2011 (has links) (PDF)
Le virus Herpes Simplex de type 1 (HSV-1) possède un mode d'infection particulier dit bimodal. Il peut soit se répliquer de manière active lors d'une phase dite lytique soit migrer dans les neurones et rester en latence. Il peut réactiver pour rétablir une infection lytique. Une protéine virale majeure dans la réactivation de HSV-1 est ICP0. C'est une protéine nucléaire à activité E3 ubiquitine ligase, qui possède la particularité d'induire la dégradation par le protéasome de plusieurs protéines centromériques constitutives, ce qui provoque une déstabilisation du centromère interphasique. Mon équipe a découvert une réponse cellulaire à l'instabilité centromérique, induite par la protéine ICP0, et nommée iCDR (pour interphase Centromere Damage Response.). L'objectif général de ma thèse est de déterminer les modifications structurales que subissent les centromères endommagés par ICP0 à l'origine de l'iCDR et probablement de la réactivation. J'ai pu démontrer qu'ICP0 affectait toute la structure protéique étroitement associée aux centromères durant l'interphase. Suite à ces résultats, j'ai pu démontrer, par des analyses de digestion de chromatine à la nucléase microccocale (MNAse), que l'occupation nucléosomique de la chromatine centromérique suite à l'activité d'ICP0 était affectée de façon significative. Une étude in vivo effectuée à partir de tissus nerveux provenant de souris infectées de manière latente, a permis de démontrer une co-localisation entre les génomes HSV-1 latents et les centromères. Cette co-localisation est associée à une répression transcriptionnelle du virus. Les résultats de ma thèse montrent donc que les effets d'ICP0 sur la déstabilisation des centromères sont en relation avec un rôle de ces centromères durant la latence. Ceci suggère fortement une implication de la déstabilisation des centromères dans le processus de réactivation contrôlé par ICP0.
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The Strucplot Framework: Visualizing Multi-way Contingency Tables with vcdMeyer, David, Zeileis, Achim, Hornik, Kurt January 2005 (has links) (PDF)
This paper describes the `strucplot' framework for the visualization of multi-way contingency tables. Strucplot displays include hierarchical conditional plots such as mosaic, association, and sieve plots, and can be combined into more complex, specialized plots for visualizing conditional independence, GLMs, and the results of independence tests. The framework's modular design allows flexible customization of the plots' graphical appearance, including shading, labeling, spacing, and legend, by means of graphical appearance control (`grapcon') functions. The framework is provided by the R package vcd. (author's abstract) / Series: Research Report Series / Department of Statistics and Mathematics
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Sexually transmitted diseases and sexual behaviour among young Swedish women : a population-based studyJonsson, Monica January 1998 (has links)
Most epidemiologic studies of sexually transmitted diseases (STD) are based on patients seeking help or advice at various health care settings. Because many STD:s are subclinical, epidemiologic surveys can be strengthened by a population-based approach. The aims of the present study were to investigate the prevalence and incidence of STDs in a population of young women, and to assess associations between STDs and social background, education, previous genital infections, sexual behaviour, contraceptive use and reproductive experience. All women belonging to the 19-, 21-, 23- and 25-year age cohorts and living in the catchment area of a community health center, were invited by mail to participate in the study. In the presence of the investigator, participants answered a structured questionaire regarding their social background, education, previous genital infections, sexual behaviour, contraceptive use and reproductive experience. A gynecologic examination was performed. Cervical scrapes for human papillomavirus (HPV) DNA, as well as samples for wet smear, cervical pap smear, and Chlamydia trachomatis (CT) culture were taken. The presence of genital warts was noted, and a colposcopy was performed 2-5 minutes after application of 5% acetic acid on the cervix and vulva. Acetowhite changes were then assessed. A serologic test for CT and herpes simplex virus type 2 (HSV-2) antibodies were performed. Of the 816 women available, 611 (75%) participated in the study. One out of four women reported symptoms from the lower genital tract. The most common were itching, followed by discharge and soreness. There was a significant correlation between the womens" complaint of vaginal discharge, and previous CT infection, lack of lactobacilli and the presence of leucocytosis in wet smear. Twenty-two percent of the women were HPV DNA positive and acetowhitening at the cervix was observed in 16% of the women. The sensitivity of detection of HPV infection by acetowhitening of the cervix was 22% (95%CI 18%, 26%), and the specificity was 90% (95% Cl 87%, 93%). C.trachomatis culture positivity was found in 2.7% of the women and the seroprevalence of CT was 24.7 %. Atypical cytology was found in 3.4% of the women and 6.6% was HSV-2 seropositiv. Of the women studied 23.6% reported having had at least one STD previously and the laboratory analysis showed 45.4% to have had at least one STD. Multivariate logistic regression analysis showed that the number of sexual partners, age at first coitus, history of therapeutic abortion, and previous pelvic inflammatory disease (PID) was independently correlated with CT seropositivity. Lifetime number of sexual partners was the only independent risk factor for HPV. Multivariate analysis showed that increasing age, early sexual debut, and a history of spontaneous abortion were independently related to the presence of HSV-2 antibodies. The lifetime number of sexual partners and coitus on first date were independently associated with a previous STD. Conclusion, We found that one out of four women had some kind of lower genital tract complaint, almost every other women had at sometime in their life an STD, and STDs were often asymptomatic. Acetowhitening of the cervix and vulva has low sensitivity, to low to warrant its use as a predictor of subclinical HPV infection. The pattern of risk factors differed between STDs. / <p>Härtill 6 uppsatser</p> / digitalisering@umu
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Etiology of oral cancerSchildt, Elsy-Britt January 1998 (has links)
<p>Härtill 5 uppsatser</p> / digitalisering@umu
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ESTUDO DOS NÍVEIS SÉRICOS DE ÁCIDO SIÁLICO EM MODELO TUMORAL E VIRALRosa, Danieli Ferrari da 27 June 2018 (has links)
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Danieli Ferrari da Rosa.pdf.jpg: 3270 bytes, checksum: 1f0862e05ecb2e7b1da2056322eeeaab (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The sialic acid is the generic name of carboxylated monosaccharides family with
nine carbon glycoconjugated at terminal portion. These molecule family are
involved in several biological processes such cell recognition processes, platelet
adhesion, migration, invasion and metastatic potential, it also work as a receptor
for bacteria and viruses. High concentrations of total sialic acid in the blood have
been reported in different groups of patients with brain tumors, leukemia,
melanoma, carcinoma and other kinds of cancers. The cleavage of sialic acid is a
crucial step in virus infection influenzae, since this acid is part of the cellular
receptor that the virus uses during the process of cellular internalization. The
neuraminidase, an enzyme produced by the virus, cleaves the bond between sialic
acid and the viral glycoproteins, allowing the entry of viruses into cells.The aim of
this study was the analysis of serum sialic acid levels in murine melanoma and
Herpes Simplex virus-1 (HSV-1) infection model. In the tumor model were used
C57BL/6 and in the viral model BALB/c mice. Mice were injected with 2x105
B16F10 cells subcutaneously in the thigh and the tumor progression was followed
each day till it became visible. The HSV-1 infection was conducted by
intraperitoneally injection of with 102 PFU of virus. The sialic acid in serum samples
was quantified by thiobarbituric method in spectrophotometer at 549 nm. A
standard curve with commercial sialic acid was used as parameter for
quantification. The results showed that in tumor model the sialic acid was
increased compared with control group and have significant difference (p <0.05) in
the first day after administration of cells. For the viral infection the concentration of
sialic acid showed a significant difference (p <0,05) in the first day after infection
when compared infected with control group. The histological analysis in thigh of
mice performed 24 hours after administration of B16F10 cells were found compact
groups of round or polygonal melanocytes with clear and large cytoplasm, irregular
chromatin, hyperchromatic and vacuolated nuclei, eosinophilic nucleoli and atypical
mitosis. / O ácido siálico é o nome genérico dado a família de monossacarídeos carboxilados
com nove átomos de carbono que aparece na porção terminal de glicoconjugados.
Estas moléculas estão envolvidas em vários processos biológicos, tais como, processos
de reconhecimento celular, adesão plaquetária, migração, invasão, potencial
metastático, sendo também um receptor para bactérias e vírus. O aumento das
concentrações séricas de ácido siálico total tem sido descrito em vários grupos de
pacientes que sofrem de tumores cerebrais, leucemia, melanoma, carcinoma e outros
tipos de cânceres. A clivagem do ácido siálico é um passo crucial para a infecção do
vírus Influenza, uma vez que este ácido é parte do receptor celular usado pelo vírus
durante o processo de internalização celular. A neuraminidase, enzima produzida pelo
vírus, cliva a ligação entre o ácido siálico e as glicoproteínas virais, permitindo a entrada
dos vírus nas células. O objetivo desse estudo foi analisar os níveis séricos de ácido
siálico em modelo de melanoma murino e modelo de infecção herpética (HSV-1). No
modelo tumoral foram utilizados camundongos C57BL/6 e no modelo viral
camundongos BALB/c. Os camundongos receberam 2x105 células B16F10 através da
administração subcutânea na coxa e a progressão do tumor foi acompanhada todos os
dias até o tumor se tornar visível. A infecção com HSV-1 foi realizada através da
administração intraperitoneal de 102 PFU de vírus. O ácido siálico das amostras de
soro foram quantificadas pelo método tiobarbitúrico em espectrofotômetro à 549 nm.
Uma curva padrão com ácido siálico comercial foi usada como parâmetro para a
quantificação. Os resultados mostraram que as concentrações de ácido siálico no
modelo tumoral foram aumentadas nos animais com tumor quando comparadas ao
grupo controle e houve diferença significativa (p< 0,05) no primeiro dia após a
administração das células. Para o modelo de infecção viral houve diferença significativa
(p< 0,05) no primeiro dia após a infecção quando comparado o grupo infectado com o
controle. Na análise histológica da coxa dos camundongos realizada após 24 horas da
administração de células B16F10 foram encontrados grupos compactos de melanócitos
arredondados ou poligonais, com citoplasma amplo e claro, cromatina irregular, núcleos
hipercromáticos e vacuolizados, nucléolos eosinofílicos e mitoses atípicas.
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Oncolytic virus therapy with HSV-1 for hematologic malignancies / がん治療用HSV-1を用いた造血器腫瘍に対するウイルス療法の開発Ishino, Ryo 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(医科学) / 甲第23109号 / 医科博第120号 / 新制||医科||8(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 河本 宏, 教授 中島 貴子, 教授 小川 誠司 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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The effect of calcium homeostasis on HSV-1 propagationDorsainvil, Mayerline 01 1900 (has links)
Au cours d'une infection lytique, le virus de l'herpès simplex de type 1 (VHS-1) doit entreprendre plusieurs étapes de fusion afin de se répliquer et se propager correctement. Ainsi, le virus a évolué afin de tirer avantage de la machinerie cellulaire en utilisant des protéines et facteurs de l’hôte à cet effet. Dans la littérature, les processus sous-jacents à l’entrée du VHS-1 ont été largement élucidés. Cependant, on ne sait toujours pas comment les particules virales nouvellement synthétisées sortent de la cellule hôte et quels facteurs cellulaires sont impliqués dans ce processus. Des résultats publiés par notre laboratoire indiquent que la protéine cellulaire, Extended Synaptotagmin 1 (E-Syt1), a un impact négatif sur la propagation globale du virus lorsqu’inhibée par de l’ARN d’interférence. Conséquemment, la présente étude a pour objectif de confirmer et d'approfondir le rôle d’E-Syt1 sur la propagation virale, en particulier sur la sortie du virus. Étant donné que l’activation d’E-Syt1 est liée à l’augmentation de la concentration de calcium cytoplasmique, nous avons également étudié l'implication du calcium au cours des stades ultérieurs de la réplication virale. Ici, nous avons démontré que la surexpression d’E-Syt1 n’a pas d’effet détectable sur la sortie du VHS-1, mais que le calcium a effet sur la propagation virale. Alors que la séquestration précoce du calcium (4 et 6 heures post-infection) à l'aide de chélateurs réprime la sortie virale, aucun effet significatif a été détecté lorsque les chélateurs ont été ajoutés à un stade avancé de l’infection (12 et 16 heures post-infection). Nos résultats fournissent des données intéressantes sur la nécessité de l’homéostasie du calcium intracellulaire afin que VHS-1 puisse assurer une médiation adéquate de la sortie virale. Ces résultats pourraient conduire à la découverte de nouveaux mécanismes ou protéines cellulaires régulées par le calcium et utilisés par le VHS-1 lors de réplications lytiques virales. / During a lytic infection, Herpes Simplex Virus type 1 (HSV-1) must go through multiple steps of fusion to replicate and propagate properly. For this purpose, the virus has evolved consequently by taking advantage of the cellular machinery using host factors and proteins. In the literature, processes underlying HSV-1’s entry have been extensively elucidated. However, it remains unclear how newly synthesized viral particles egress from the host cell, and what cellular factors are implicated in this process. Results published by our laboratory suggest that the cellular protein, Extended Synaptotagmin 1 (E-Syt1), has a negative and global impact on the viral propagation when down regulated by RNA interference. Consequently, this study aims to confirm and deepen our understanding of E-Syt1’s role on HSV-1, particularly during viral egress. Since activation of E-Syt1 is linked to the increase in cytoplasmic calcium concentration, we also investigated calcium involvement during later stages of viral propagation. Interestingly, overexpression of E-Syt1 had no measurable effect on HSV-1 propagation whereas calcium has a dual effect on viral propagation. While early calcium sequestering (4 and 6 hours post-infection) using chelators represses viral egress, no significant effect was detected when chelators were added at later time points (12 and 16 hours post-infection). Our results give interesting insights on how HSV-1 relies on intracellular calcium homeostasis to properly mediate viral egress. These results may lead to the discovery of new mechanisms or cellular proteins that are regulated by calcium and hijacked by HSV-1 during lytic replication.
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Funktionelle Interaktionen von Tau mit anderen Proteinen, die bei der Alzheimer´schen Krankheit beteiligt sindLeschik, Julia 03 November 2005 (has links)
Die Alzheimer-Krankheit (AD) ist gekennzeichnet durch ein massives Absterben von Neuronen in bestimmten Gehirnregionen. Die zwei charakteristischen histopathologischen Hauptmerkmale sind extrazelluläre Amyloidplaques bestehend aus dem APP-Peptidfragment Abeta und intrazelluläre Fibrillen hyperphosphorylierten Tau-Proteins. Familiäre Formen von AD (FAD) werden verursacht durch Mutationen in den beiden sehr homologen Presenilin-Genen 1 und 2 oder dem APP-Gen. Verschiedene Studien zeigen, dass ein Zusammenhang zwischen Presenilin Mutationen, Abeta-Generierung und Tau-Phosphorylierung beim Auslösen des Neuronentods vorliegt. Immer noch ungeklärt ist, inwiefern Abeta und Presenilin die Tau-abhängige Degeneration beeinflussen. In dieser Arbeit wird gezeigt, dass eine HSV-1-vermittelte Expression von fluoreszenzmarkiertem Tau in kortikalen Primärkulturen einen neurotoxischen Effekt ausübt. Dieser ist drastisch erhöht bei Verwendung eines Konstruktes, welches die pathologische Hyperphosphorylierung von Tau simuliert (pseudohyperphosphoryliertes Tau (PHP-Tau)). Die durch PHP-Tau induzierte Neurodegeneration ist assoziiert mit einer Induktion apoptotischer Mechanismen. Die transgene Expression von wildtyp (wt), aber nicht von FAD-mutiertem PS1 (M146L), unterdrückt PHP-Tau-induzierte Neurodegeneration. Dagegen erhöht die transgene Expression mutierten APPs (SDL) die Degeneration und Phosphorylierung in der Gegenwart von wt, aber nicht von PHP-Tau. Die Daten weisen darauf hin, dass wt und FAD-mutiertes PS1 sowie Abeta die Neurodegeneration durch differentielle Mechanismen modulieren, wobei die Hyperphosphorylierung von Tau entscheidend beteiligt ist. Abeta amplifiziert die Tau-induzierte Neurodegeneration durch die erhöhte Modifikation von Tau. Während PS1 wt der Neurodegeneration durch modifiziertes Tau entgegenwirkt, besitzt FAD-mutiertes PS1 diese Funktion nicht mehr. Demnach könnte die Unterdrückung der Tau-Phosphorylierung eine effektive Therapiemöglichkeit darstellen.
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Enhanced Antiviral Function of Magnesium Chloride-Modified Heparin on a Broad Spectrum of VirusesMese, Kemal, Bunz, Oskar, Volkwein, Wolfram, Vemulapalli, Sahithya P.B., Zhang, Wenli, Schellhorn, Sebastian, Heenemann, Kristin, Rueckner, Antje, Sing, Andreas, Vahlenkamp, Thomas W., Severing, Anna-Lena, Gao, Jian, Aydin, Malik, Jung, Dominik, Bachmann, Hagen S., Zänker, Kurt S., Busch, Ulrich, Baiker, Armin, Griesinger, Christian, Ehrhardt, Anja 22 January 2024 (has links)
Previous studies reported on the broad-spectrum antiviral function of heparin. Here we
investigated the antiviral function of magnesium-modified heparin and found that modified heparin
displayed a significantly enhanced antiviral function against human adenovirus (HAdV) in immortalized
and primary cells. Nuclear magnetic resonance analyses revealed a conformational change
of heparin when complexed with magnesium. To broadly explore this discovery, we tested the
antiviral function of modified heparin against herpes simplex virus type 1 (HSV-1) and found that the
replication of HSV-1 was even further decreased compared to aciclovir. Moreover, we investigated the
antiviral effect against the new severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)
and measured a 55-fold decreased viral load in the supernatant of infected cells associated with a
38-fold decrease in virus growth. The advantage of our modified heparin is an increased antiviral
effect compared to regular heparin.
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HSV-1 Infection of C3H Central Nervous System Cell LinesVan Buren, Lauren Kay 27 September 2007 (has links)
No description available.
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