Research Question: What are patients’ experiences of technology in adult intensive care? Research Objectives: -To explore patients’ perceptions of receiving care in a technological environment -To explore patients’ perceptions of how technology has influenced their experience of care Background: Technology is fundamental to the physical recovery of critically ill patients in intensive care (ICU), however, there is a suggestion in the literature that its presence may dehumanise patient care and distract the nurse from attending to patients’ psychosocial needs. Little attention has been paid to patients’ perceptions of receiving care in a technological environment. The purpose of this research, therefore, was to explore patients’ experiences of technology and care within ICU. Methods: This study was informed by Heideggerian phenomenology. The research took place in a university hospital in England. Nineteen participants who had been a patient in ICU were interviewed using a semi-structured approach. Interviews were transcribed verbatim and analysed utilising Van Manen’s framework. Findings: Resulting themes were ‘My Useless Body’ which describes how participants experienced their body as dysfunctional, disconnected and invaded by technology, ‘Making Sense of It’, which describes how participants rationalised their experiences by constructing a story, and ‘Technology and Care’, which describes how and why participants endured technologies in ICU. Conclusions: The disintegrated body is central to the critically ill’s experiences in ICU. Families play an important role in helping patients make sense of their experiences by filling in gaps in memory and helping them to sort the real from unreal memories. Families therefore require support and information resources in fulfilling this role. Patients experience technology and care as a series of paradoxical relationships: alienating yet reassuring, uncomfortable yet comforting, impersonal yet personal. Nurses maintaining a close and supportive presence and providing personal comfort and care may minimise the invasive and isolating potential of technology

This study is about the selection of test groups for a user test. The natural choice for company is to choose people that are included in the target group for the product or system that are about to be tested. This is something I have chosen to focus on. Is there reason to believe that you would choose people to your test group that are not part of the target audience and still produce an equally good result? To learn more about this, a test is conducted on a product that has one focus area and a clear target audience, in this case Snapchat. This research is showing that it’s a difference depending on what people are picked for the test. The two different groups focused on different things in the test that gave different goals to follow.

No description available.

The vitamin D receptor (VDR) is a transcription factor mediating genomic responses to the biologically active form of vitamin D, 1,25(OH)2D3, a key modulator of the immune system. Knowledge on how these polymorphisms modulate the vitamin D endocrine system and confer risk of disease is hindered by the fact that several of the associated allelic variants are located in introns or are synonymous and likely serve as markers within an extended haplotype covering disease-causing alleles. The functional relevance of VDR polymorphisms need to be studied in the context of the haplotype, comparing haplotypes with the process of DNA transcription, protein levels and biological function. These functional studies should be performed using techniques reflecting the in vivo, naturally occurring milieu as close as possible. VDR has several known allelic variants including a FokI restriction fragment length polymorphism in exon II, BsmI and ApaI polymorphisms in the intron VIII, and a synonymous TaqI variant in exon IX. The aim of the current study was the identification of sequence variants in VDR, to define haplotype patterns in the Caucasian population and to understand the functional consequences of single nucleotide polymorphisms (SNPs) and haplotypes. Methods: EBV transformed B-lymphocyte cell lines, from twenty-three individuals, within the Caucasian population were established. Polymorphisms and haplotypes in VDR were identified by genotyping and sequencing. Quantification of the VDR protein level measured with flow cytometry was studied together with the genotype and haplotype data to determine possible influence of genotypes or haplotype and VDR protein levels. Biological function was analysed by the percentage inhibition that each individual experienced in the presence of 1,25(OH)2D3, measured by the Alamar Blue assay and the Trypan blue dye exclusion method. Results: The results showed thatVDR genotypes and haplotypes may not influence VDR protein level although certain genotypes and haplotypes significantly influenced biological function. It was proposed that VDR variants may account for significant influences on cellular responsiveness to 1,25(OH)2D3 as mediated by VDR. Conclusions: The findings of the current study suggest that individual SNPs and haplotypes of VDR influences quality of the repose in the presence of 1,25(OH)2D3, rather than quantity of the VDR levels. This knowledge may permit a rational choice of polymorphisms to use in epidemiology studies or improve our understanding of the significance of VDR genetic polymorphisms on biological function. Keywords: functionality, polymorphism, haplotype, vitamin D receptor, VDR, 1,25(OH)2D3, structure-function analysis, biological responsiveness. / Prof. L. Bornman

<p>The humoral immune system plays a critical role in the clearance of numerous pathogens. In the setting of HIV-1 infection, the virus infects, integrates its genome into the host's cells, replicates, and establishes a reservoir of virus-infected cells. The initial antibody response to HIV-1 infection is targeted to non-neutralizing epitopes on HIV-1 Env gp41, and when a neutralizing response does develop months after transmission, it is specific for the autologous founder virus and the virus escapes rapidly. After continuous waves of antibody mediated neutralization and viral escape, a small subset of infected individuals eventually develop broad and potent heterologous neutralizing antibodies years after infection. In this dissertation, I have studied the ontogeny of mucosal and systemic antibody responses to HIV-1 infection by means of three distinct aims: 1. Determine the origin of the initial antibody response to HIV-1 infection. 2. Characterize the role of restricted VH and VL gene segment usage in shaping the antibody response to HIV-1 infection. 3. Determine the role of persistence of B cell clonal lineages in shaping the mutation frequencies of HIV-1 reactive antibodies. </p><p>After the introduction (Chapter 1) and methods (Chapter 2), Chapter 3 of this dissertation describes a study of the antibody response of terminal ileum B cells to HIV-1 envelope (Env) in early and chronic HIV-1 infection and provides evidence for the role of environmental antigens in shaping the repertoire of B cells that respond to HIV-1 infection. Previous work by Liao et al. demonstrated that the initial plasma cell response in the blood to acute HIV-1 infection is to gp41 and is derived from a polyreactive memory B cell pool. Many of these antibodies cross-reacted with commensal bacteria, Therefore, in Chapter 3, the relationship of intestinal B cell reactivity with commensal bacteria to HIV-1 infection-induced antibody response was probed using single B cell sorting, reverse transcription and nested polymerase chain reaction (RT- PCR) methods, and recombinant antibody technology. The dominant B cell response in the terminal ileum was to HIV-1 envelope (Env) gp41, and 82% of gp41- reactive antibodies cross-reacted with commensal bacteria whole cell lysates. Pyrosequencing of blood B cells revealed HIV-1 antibody clonal lineages shared between ileum and blood. Mutated IgG antibodies cross-reactive with both Env gp41 and commensal bacteria could also be isolated from the terminal ileum of HIV-1 uninfected individuals. Thus, the antibody response to HIV-1 can be shaped by intestinal B cells stimulated by commensal bacteria prior to HIV-1 infection to develop a pre-infection pool of memory B cells cross-reactive with HIV-1 gp41.</p><p>Chapter 4 details the study of restricted VH and VL gene segment usage for gp41 and gp120 antibody induction following acute HIV-1 infection; mutations in gp41 lead to virus enhanced neutralization sensitivity. The B cell repertoire of antibodies induced in a HIV-1 infected African individual, CAP206, who developed broadly neutralizing antibodies (bnAbs) directed to the HIV-1 envelope gp41 membrane proximal external region (MPER), is characterized. Understanding the selection of virus mutants by neutralizing antibodies is critical to understanding the role of antibodies in control of HIV-1 replication and prevention from HIV-1 infection. Previously, an MPER neutralizing antibody, CAP206-CH12, with the binding footprint identical to that of MPER broadly neutralizing antibody 4E10, that like 4E10 utilized the VH1-69 and VK3-20 variable gene segments was isolated from this individual (Morris et al., 2011). Using single B cell sorting, RT- PCR methods, and recombinant antibody technology, Chapter 4 describes the isolation of a VH1-69, Vk3-20 glycan-dependent clonal lineage from CAP206, targeted to gp120, that has the property of neutralizing a neutralization sensitive CAP206 transmitted/founder (T/F) and heterologous viruses with mutations at amino acids 680 or 681 in the MPER 4E10/CH12 binding site. These data demonstrate sites within the MPER bnAb epitope (aa 680-681) in which mutations can be selected that lead to viruses with enhanced sensitivity to autologous and heterologous neutralizing antibodies. </p><p>In Chapter 5, I have completed a comparison of evolution of B cell clonal lineages in two HIV-1 infected individuals who have a predominant VH1-69 response to HIV-1 infection--one who produces broadly neutralizing MPER-reactive mAbs and one who does not. Autologous neutralization in the plasma takes ~12 weeks to develop (Gray et al., 2007; Tomaras et al., 2008b). Only a small subset of HIV-1 infected individuals develops high plasma levels of broad and potent heterologous neutralization, and when it does occur, it typically takes 3-4 years to develop (Euler et al., 2010; Gray et al., 2007; 2011; Tomaras et al., 2011). The HIV-1 bnAbs that have been isolated to date have a number of unusual characteristics including, autoreactivity and high levels of somatic hypermutations, which are typically tightly regulated by immune control mechanisms (Haynes et al., 2005; 2012b; Kwong and Mascola, 2012; Scheid et al., 2009a). The VH mutation frequencies of bnAbs average ~15% but have been shown to be as high as 32% (reviewed in Mascola and Haynes, 2013; Kwong and Mascola, 2012). The high frequency of somatic hypermutations suggests that the B cell clonal lineages that eventually produce bnAbs undergo high-levels of affinity maturation, implying prolonged germinal center (GC) reactions and high levels of T cell help. To study the duration of HIV-1- reactive B cell clonal persistence, HIV-1 reactive and non HIV-1- reactive B cell clonal lineages were isolated from an HIV-1 infected individual that produces bnAbs, CAP206, and an HIV-1 infected individual who does not produce bnAbs, 004-0. Single B cell sorting, RT-PCR and recombinant antibody technology was used to isolate and produce monoclonal antibodies from multiple time points from each individual. B cell sequences clonally related to mAbs isolated by single cell PCR were identified within pyrosequences of longitudinal samples of these two individuals. Both individuals produced long-lived B cell clones that persisted from 0-232 weeks in CAP206, and 0-238 weeks in 004-0. The average length of persistence of clones containing members isolated from two separate time points was 91.5 weeks both individuals. Examples of the continued evolution of clonal lineages were observed in both the bnAb and non-bnAb individual. These data indicated that the ability to generate persistent and evolving B cell clonal lineages occurs in both bnAb and non-bnAb individuals, suggesting that some alternative host or viral factor is critical for the generation of highly mutated broadly neutralizing antibodies. </p><p> Together the studies described in Chapter 3-5 show that multiple factors influence the antibody response to HIV-1 infection. The initial antibody response to HIV-1 Env gp41 can be shaped by a B cell response to intestinal commensal bacteria prior to HIV-1 infection. VH and VL gene segment restriction can impact the B cell response to multiple HIV-1 antigens, and virus escape mutations in the MPER can confer enhanced neutralization sensitivity to autologous and heterologous antibodies. Finally, the ability to generate long-lived HIV-1 clonal lineages in and of itself does not confer on the host the ability to produce bnAbs.</p> / Dissertation

Various studies suggest tannins act as antioxidants, anticarcinogens, cardio-protectants, anti-inflammatory agents, and antimicrobials. However, more investigation is needed to examine the bioavailability of tannins. Tannins bind to salivary peptides by hydrophilic and hydrophobic mechanisms. Electrospray Ionization Mass Spectrometry (ESI-MS) has been used to assess both hydrophilic and hydrophobic components of protein complexes. ESI-MS could potentially be an effective tool for screening the bioavailability of tannins. Weaker binding tannins are predicted to be more highly absorbed by the body, and should therefore exhibit greater bioavailability. Rannulu and Cole have used ESI-MS to measure binding affinities of procyanidin tannin stereoisomers for salivary peptides in aqueous solution. The condensed tannins procyanidin B1, B2, B3, and B4 demonstrated significantly different binding affinities (binding strengths) for the Histatin 5 salivary peptide. The procyanidin-Histatin 5 binding mechanisms in the ESI-MS experiments by Rannulu and Cole were investigated using the FRED docking program combined with molecular dynamics optimization in the AMBER software suite. The simulations suggest residual liquid-phase binding interactions in procyanidin-Histatin 5 complexes are maintained in the gas phase under conditions resembling those in ESI-MS experiments, though the gas-phase interaction energies were enhanced. Increased hydrogen bonding and decreased π-π stacking interactions were also detected in gas versus liquid-phase procyanidin-Histatin 5 complexes. In addition, simulation results suggest multiple conformations of procyanidins bind Histatin 5 at several sites and procyanidin binding does not fix the Histatin 5 peptide backbone. The simulations agree with previous studies which indicate aromatic Histatin 5 residues are responsible for procyanidin-Histatin 5 binding and tannins can bind salivary peptides in multiple conformations. The effects of Hofmeister salts on complexation of an amphiphilic guest adamantane carboxylic acid to the hydrophobic surface of a deep-cavity cavitand have been investigated by Gibb et al. Adamantane-cavitand binding was found to be largely enthalpically driven, though adamantane binding in the presence of the salting-in anions perchlorate and thiocyanate was entropically driven. Gibb et al. also found that perchlorate-cavitand binding was enthalpically favorable, though entropically unfavorable. Potential-of-mean-force (PMF) calculations for perchlorate-cavitand and thiocyanate-cavitand complexation were performed using umbrella sampling with a modified version of the sander module from the Amber 9 software suite to further investigate the thermodynamic properties of Hofmeister-anion binding to the hydrophobic cavitand. The enthalpy for salting-in anion-cavitand complexation was calculated from the potential energy difference between the bound and unbound state (the potential energy of binding) along with the entropy. The binding entropy and enthalpy were also calculated using a finite difference approximation to the entropy. The enthalpy for perchlorate-cavitand complexation calculated from the binding energy and the finite difference approximation to the entropy was favorable with an unfavorable entropy. The binding enthalpy and entropy for thiocyanate-cavitand complexation calculated from the binding energy and finite difference approximation to the entropy were unfavorable and favorable, respectively, perhaps due to a classical hydrophobic effect. The orientation of the ligand, the number of water molecules displaced from the ligand and cavitand upon complexation, and the number of nearest-neighbor atom contacts between the ligand and the cavitand were also calculated. Additionally, the energetics of various interactions involved in salting-in anion-cavitand complexation including the anion-cavitand, anion-water, cavitand-water, and water-water interactions were assessed, though the data were inconclusive.

Memoria para optar al Título Profesional de Médico Veterinario / Trypanosoma cruzi, como agente etiológico de la enfermedad de Chagas, es uno de los principales problemas de salud pública en diversos países latinoamericanos. De acuerdo con la Organización Panamericana de la Salud (OPS), existirían alrededor de 18 millones de personas infectadas en el continente. A su vez, la Organización Mundial de la Salud (OMS) indica que en el cono sur alrededor de 50 millones de personas están expuestas al riesgo de infectarse. El conocimiento de la magnitud de la infección chagásica, su repercusión sobre la salud y la economía de los países latinoamericanos, varía grandemente, en especial, sus formas clínicas. La caracterización genética de las variedades de T. cruzi es de suma importancia, debido a la considerable heterogeneidad genética y biológica en las poblaciones de este parásito. Se han descritos previamente dos linajes filogenéticos importantes, ambos muy heterogéneos; T.cruzi I y T.cruzi II. En la presente memoria se han caracterizado nueve cepas a través de la secuenciación del gen para citocromo b y su posterior análisis filogenético, el cual se realizó junto al total de cepas descritas en GenBank para citocromo b de T. cruzi. Los resultados obtenidos muestran una topología que divide las diferentes cepas en tres Clados principales (Clado A, B y C), lo cual reafirma resultados obtenidos en diversos estudios previos. Las muestras chilenas se distribuyen en los tres clados, pero principalmente en el Clado A, cuyas cepas están clasificadas como T. cruzi I según la nomenclatura internacional

Ankyrin B (AnkB) is a scaffolding protein, acting as a bridge between ion channels and cytoskeleton networks. AnkB variants are associated with cognitive disorders including autism spectrum disorder and epilepsy. In the brain, AnkB interacts with Cav2.1, the pore-forming subunit of P/Q type voltage gated calcium channels. However, how AnkB regulates Cav2.1 is not fully understood. Using HEK293T cells, we discovered that AnkB increases Cav2.1 expression levels but does not change Cav2.1 surface levels. AnkB p.S646F increases Cav2.1 to an even greater level of expression, again without impacting Cav2.1 surface levels. Looking at a partial loss of AnkB in glutamatergic neurons, overall Cav2.1 levels decreased at P30 but the synaptosomal fraction was not impacted. Our findings indicate that AnkB plays a role in regulating an intracellular pool of Cav2.1 but does not affect the surface or the synaptosomal pools of Cav2.1. This intracellular pool of Cav2.1 may play an important role in neuronal function and homeostasis, suggesting a mechanism for neuronal pathogenicity of AnkB variants. / Graduate / 2020-08-06

Flavonoide sind weitverbreitete sekundäre Pflanzeninhaltsstoffe. Ihr Beitrag zur Prävention von chronischen Erkrankungen wird zu großen Teilen auf immunmodulatorische und neuroprotektive Effekte zurückgeführt. Eine Voraussetzung für die Nutzung dieser Eigenschaften der Flavonoide stellt die Erfassung cytotoxischer Effekte dar. Mit Ausnahme von Xanthohumol und Quercetin ist für alle im Rahmen der vorliegenden Arbeit untersuchten Flavonoide, Hispidulin, Baicalein, Scutellarein, Hesperetin, Chrysin, Apigenin, Naringenin, Catechin, Pelargonidinchlorid und EMD 21388, sowohl in T-Zellen (Jurkat) als auch in neuronalen (SK-N-SH)-Zellen nach 24-stündiger Inkubation eine geringgradige Cytotoxizität festzuhalten. Für Xanthohumol bzw. Quercetin wird ein halbmaximaler Verlust der Zellvitalität je nach Modell in Konzentrationen von 33-45 µM bzw. 118-208 µM erreicht. Der weiterführenden Charakterisierung (zVAD, DNA-Laddering) ist zu entnehmen, dass die zellulären Veränderungen substanzabhängig differieren und sowohl nekrotische Mechanismen (Xanthohumol) als auch apoptotische Vorgänge (Quercetin) einschließen. Eine erhöhte Lipidperoxidation im oberen Dosisbereich lässt darüber hinaus auf eine Beteiligung von oxidativem Stress an den von Xanthohumol-induzierten nekrotischen Prozessen schließen. Eine positive Einflussnahme auf die Zellvitalität durch Antioxidantien wie GSH und NAC lässt des Weiteren vermuten, dass die erfassten Flavonoid-induzierten Prozesse jeweils sensitiv zum Redoxzustand der Zelle sind. Während die Effekte von Xanthohumol auch in anderen Zellmodellen (HL-60) nachweisbar bleiben, verhält sich Quercetin nicht durchgehend vitalitätsmindernd. Unterschiede zwischen den Testsubstanzen bestehen auch hinsichtlich antioxidativer Effekte. Das Eliminieren freier Radikale zählt zu den wichtigsten Mechanismen, die bei Flavonoid-vermittelter Neuroprotektion eine Rolle spielen. Insgesamt sind alle diesbezüglich untersuchten Substanzen als starke Superoxidanionen-Radikalfänger einzustufen. Im Co-Inkubationsversuch zeigt Scutellarein den stärksten Effekt, gefolgt von Quercetin, Hispidulin und Xanthohumol. Im Prä-Inkubations-Versuchsmodell liegen in der Reihenfolge ihrer Effektstärken Xanthohumol vor Quercetin, Hispidulin und schließlich Scutellarein. Die modellabhängigen Konstanten können, unter Beteiligung einer passiven Diffusion der hydrophoben Flavonoidaglykone, auf eine substanzgebundene Membranpermeabilität zurückzuführen sein. Das antioxidative Potential der Flavonoide resultiert u.a. aus einer komplexen Einflußnahme auf die Genexpression in der Zelle. In der vorliegenden Arbeit sind anhand von cDNA-Arrays für mehrere Vertreter übereinstimmend Wechselwirkungen mit Genen der zellulären Abwehr dargestellt. Demnach führen Scutellarein, Hispidulin, Quercetin und Xanthohumol zu einer deutlich reduzierten Expressionsstärke von STK4, CHD4, ARHGDIB, IL16, ISG20, PFN1 und SOD2. Unter den Flavonoid-induzierten Veränderungen ragen die Effekte auf ADAR1 heraus, dessen Genexpression von Scutellarein bis auf ein 0,1-faches der Referenzwerte reduziert wird. Gleichsinnige Auswirkungen von Scutellarein auf die Expression von ADAR1-Protein in Western Blots unterstreichen diese Interaktion und legen nahe, dass ADAR-vermittelte enzymatische Deaminierungen durch Flavonoide moduliert werden können. Diese Beobachtung wird ergänzt durch den nachgewiesenen Effekt von Flavonoiden auf die Expression einer Reihe weiterer Gene (ADAR2, APOBEC3B, APOBEC3C, APOBEC3F und APOBEC3G), die analoge posttranskriptionale Mechanismen steuern und gleichermaßen in Immunabwehr und Neuroprotektion eingebunden sind. Zu den wichtigsten Substraten von ADAR zählen Glutamatrezeptoren. Erwartungsgemäß ist nach der Einwirkung von Scutellarein auf humane Zellen, die Glutamatrezeptoren exprimieren, ein Rückgang der Deaminierung im Bereich der Glutamatrezeptoruntereinheit GluR 2 zu verzeichnen (Q/R-Position). Dem entspricht in elektrophysiologischen Modellen eine gesteigerte Ca2+-Permeabilität der jeweiligen Ionenkanäle und eine veränderte neuronale Exzitabilität. Hieraus ergibt sich ein breites Spektrum zusätzlicher Optionen für die Induktion von gesundheitsrelevanten Flavonoidfunktionen in der Zelle. So spielt die Modulation von Deaminierungen zugleich eine entscheidende Rolle im Vermehrungszyklus viraler Erreger. Die Annahme einer möglichen antiviralen Qualität von Scutellarein wird durch ein HBV-Infektionsmodell anhand drei Parameter der Virusreplikation (Virus-DNA-Konzentration, HBs- bzw. HBe-Antigenproduktion) bestätigt. Offen bleibt auch nach ausführlicher Prüfung, ob der deutliche antivirale Effekt als das Produkt von Flavonoid-induzierten Veränderungen der Deaminierungsraten oder als Folge eines Effekts auf die virale Polymerase zu interpretieren ist. Die hier dargestellten Wirkmechanismen leisten einen Beitrag zum Verständnis der Bedeutung von Flavonoiden für neue Anwendungen in Neuroprotektion und Immunabwehr. / Flavonoids are common secondary plant metabolites that confer numerous nutritional health effects. Their role in preventing chronic diseases is attributed to immunmodulatory and neuroprotective effects among others. In order to fully exploit these properties the limitations imposed by the compounds cytotoxic profiles must be addressed. For the majority of compounds investigated, hispidulin, baicalein, scutellarein, hesperetin, chrysin, apigenin, naringenin, catechin, pelargonidinchloride and EMD 21388, the present study confirms minimal cytotoxicity in T-cells (Jurkat) and in neuronal cells (SK-N-SH). As for xanthohumol and quercetin a 50% decline in cell-vitality is observed at concentrations of 33-45 µM and 118-208 µM, respectively. Further characterization using zVAD and DNA-laddering indicate that cell-vitality may be compromised both by necrotic mechanisms (xanthohumol) and by apoptotic effects (quercetin). An increase in lipidperoxidation in the upper dose range suggests that oxidative stress may be involved in xanthohumol toxicity. As this is counteracted by antioxidants such as GSH and NAC, these flavonoids impact on cell-vitality is likely codetermined by the cells redox state. While the effects of xanthohumol extend to other cell models, quercetin toxicity in HL-60 cells is less pronounced. Test compounds are also found to differ with regard to antioxidative profiles. The elimination of free radicals is a key mechanism in flavonoid-induced neuroprotection and is shown to vary with different incubation protocols. In short incubation experiments (5 min; co-incubation) scutellarein is identified as the most powerful scavenger, followed by quercetin, hispidulin and xanthohumol. In prolonged incubations (24 hrs; prä-incubation) xanthohumol and quercetin are followed by hispidulin and scutellarein. Model-specific constants suggest that passive diffusion of the hydrophobic flavonoid-aglyca may occur across cell membranes, alongside with other modes of permeation. Flavonoids antioxidative potential is mediated by complex effects on gene expression. The present work uses data from cDNA-arrays to highlight interactions with genes involved in cellular defense. Specifically, scutellarein, hispidulin, quercetin and xanthohumol downregulate expression for STK4, CHD4, ARHGDIB, IL16, ISG20, PFN1 and SOD2. In addition, flavonoids consistently downregulate ADAR1-expression, which drops to 0,1-fold of reference values and is paralleled by scutellarein-effects on ADAR1-protein-expression. Together, these findings indicate, that ADAR-mediated enzymatic deamination may be modulated by flavonoids. Similar effects are noted on related genes (ADAR2, APOBEC3B, APOBEC3C, APOBEC3F and APOBEC3G), relevant to posttranscriptional processing underlying immune defense and neuroprotection. Glutamate receptors count among the most important neuronal substrates of ADAR. Following exposure to scutellarein a decrease in deamination rates is confirmed with respect to the glutamate receptor subunit GluR 2 (Q/R-site). As a result, an enhanced Ca2+-permeability of the respective ion channels is anticipated, and modified neuronal excitability. Overall, the regulation of enzymatic deamination by flavonoids offers opportunities for multilevel balancing of cell homeostasis. Thus deaminations may interfere with the replication cycle of viral pathogens. Using an ex-vivo HBV-infection model and three parameters of viral replication (viral load, HBs and HBe indices), antiviral properties of scutellarein are illustrated. Despite extensive investigation, it remains to be seen whether these effects can be ascribed to deaminations of viral DNA or to an interaction with other substrates, e.g. the viral polymerase. In summary, the present observations serve to foster our understanding of flavonoids roles in neuroprotection and immune defense.

Background: The frequency of the most observed cancer, Non Hodgkin Lymphoma (NHL), is further rising. Diffuse large B-cell lymphoma (DLBCL) is the most common of the NHLs. There are two subgroups of DLBCL with different gene expression patterns: ABC (“Activated B-like DLBCL”) and GCB (“Germinal Center B-like DLBCL”). Without therapy the patients often die within a few months, the ABC type exhibits the more aggressive behaviour. A further B-cell lymphoma is the Mantle cell lymphoma (MCL). It is rare and shows very poor prognosis. There is no cure yet. Methods: In this project these B-cell lymphomas were examined with methods from bioinformatics, to find new characteristics or undiscovered events on the molecular level. This would improve understanding and therapy of lymphomas. For this purpose we used survival, gene expression and comparative genomic hybridization (CGH) data. In some clinical studies, you get large data sets, from which one can reveal yet unknown trends. Results (MCL): The published proliferation signature correlates directly with survival. Exploratory analyses of gene expression and CGH data of MCL samples (n=71) revealed a valid grouping according to the median of the proliferation signature values. The second axis of correspondence analysis distinguishes between good and bad prognosis. Statistical testing (moderate t-test, Wilcoxon rank-sum test) showed differences in the cell cycle and delivered a network of kinases, which are responsible for the difference between good and bad prognosis. A set of seven genes (CENPE, CDC20, HPRT1, CDC2, BIRC5, ASPM, IGF2BP3) predicted, similarly well, survival patterns as proliferation signature with 20 genes. Furthermore, some bands could be associated with prognosis in the explorative analysis (chromosome 9: 9p24, 9p23, 9p22, 9p21, 9q33 and 9q34). Results (DLBCL): New normalization of gene expression data of DLBCL patients revealed better separation of risk groups by the 2002 published signature based predictor. We could achieve, similarly well, a separation with six genes. Exploratory analysis of gene expression data could confirm the subgroups ABC and GCB. We recognized a clear difference in early and late cell cycle stages of cell cycle genes, which can separate ABC and GCB. Classical lymphoma and best separating genes form a network, which can classify and explain the ABC and GCB groups. Together with gene sets which identify ABC and GCB we get a network, which can classify and explain the ABC and GCB groups (ASB13, BCL2, BCL6, BCL7A, CCND2, COL3A1, CTGF, FN1, FOXP1, IGHM, IRF4, LMO2, LRMP, MAPK10, MME, MYBL1, NEIL1 and SH3BP5; Altogether these findings are useful for diagnosis, prognosis and therapy (cytostatic drugs). / Hintergrund: Die Häufigkeit von Non-Hodgkin-Lymphomen (NHL), den am meisten beobachteten Krebserkrankungen, steigt weiter an. Von den aggressiven Non-Hodgkin-Lymphomen (NHL) macht das “großzellige, diffuse B-Zell-Lymphom” (DLBCL) den größten Anteil aus. Durch Genexpressionsmuster wurden zwei Subtypen definiert: ACB (“Activated B-like DLBCL”) und GCB (“Germinal Center B-like DLBCL”). Die Patienten der Gruppe ABC sterben ohne Therapie oft innerhalb weniger Monate, weil der ABC Typ einen aggressiveren Krankheitsverlauf aufweist. Ein weiteres, von einer malignen Entartung der B-Lymphozyten ausgehendes Lymphom, ist das “Mantelzell Lymphom” (MCL). Es tritt selten auf und ist ebenfalls mit einer schlechten Prognose verbunden. Eine vollständige Heilung nach der Therapie ist sehr selten. Methoden: In diesem Projekt wurden diese B-zell Lymphome mit bioinformatischen Methoden untersucht, um auf molekularer Ebene neue Eigenschaften oder bisher unentdeckte Zusammenhänge zu finden. Das würde das Verständnis und damit auch die Therapie voranbringen. Dafür standen uns Überlebens-, Genexpressions- und chromosomale Aberrationsdaten zur Verfügung. Sie sind die bevorzugte Wahl der Mittel, um genetische Veränderungen in Tumorzellen zu bestimmen. Hierbei fallen oft große Datenmengen an, aus welchen man mit bioinformatischen Methoden vorher unerkannte Trends und Hinweise identifizieren kann. Ergebnisse (MCL): Explorative Analysen sowohl der Genexpressions- (zweite Hauptachse der Korrespondenz Analyse) als auch der chromosomalen Aberrationsdaten des Mantelzell-Lymphom zeigten uns hierbei, daß es trotz der linearen Korrelation zwischen der veröffentlichten Proliferationssignatur und der Überlebenszeit sinnvoll ist, in den Patienten (n=71) zwei Ausprägungen zu betrachten: Patienten mit schlechter und mit guter Prognose. Statistische Tests (moderate t-test, Wilcoxon rank-sum test) dieser beiden Typen zeigten Unterschiede im Zellzyklus und ein Netzwerk von Kinasen auf, welche für den Unterschied zwischen guter und schlechter Prognose verantwortlich sind. Sieben Gene (CENPE, CDC20, HPRT1, CDC2, BIRC5, ASPM, IGF2BP3) konnten gefunden werden, die eine ähnliche gute Prognose für Überlebenszeiten ermöglichen, wie eine früher veröffentlichte Proliferationssignatur mit 20 Genen. Außerdem konnten chromosomale Banden durch eine explorative Analyse mit der Prognose assoziiert werden (Chromosom 9: 9p24, 9p23, 9p22, 9p21, 9q33 and 9q34). Ergebnisse (DLBCL): Durch geeignete Normalisierung der Genexpressionsdaten von 248 DLBCL-Patienten trennte der Signatur basierte Predictor die Risikogruppen nun besser auf. Eine ähnlich gute Auftrennung konnte von uns sogar mit sechs Genen erreicht werden. Die explorative Analyse der Genexpressionsdaten konnte die Subtypen ABC und GCB als valide Gruppen bestätigen. In den Genen, die ABC und GCB unterscheiden, ergab sich eine Häufung in späten und frühen Zellzyklusstadien. Klassische Lymphommarker, neu aufgefundene spezielle Gene und Zellzyklusgene bilden ein Netzwerk, das die ABC und GCB Gruppen klassifizieren und Unterschiede in deren Regulation erklären kann (ASB13, BCL2, BCL6, BCL7A, CCND2, COL3A1, CTGF, FN1, FOXP1, IGHM, IRF4, LMO2, LRMP, MAPK10, MME, MYBL1, NEIL1 and SH3BP5. 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