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Search Results: 1 - 10 of 3005 matches for " Bianca Hoffmann "
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The HIV-1 Rev Protein Enhances Encapsidation of Unspliced and Spliced, RRE-Containing Lentiviral Vector RNA
Bastian Grewe, Katrin Ehrhardt, Bianca Hoffmann, Maik Blissenbach, Sabine Brandt, Klaus überla
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048688
Abstract: Background During the RNA encapsidation process of human immunodeficiency virus (HIV) viral genomic, unspliced RNA (gRNA) is preferentially incorporated into assembling virions. However, a certain amount of spliced viral transcripts can also be detected in viral particles. Recently, we observed that nuclear export of HIV and lentiviral vector gRNA by Rev is required for efficient encapsidation. Since singly-spliced HIV transcripts also contain the Rev-response element (RRE), we investigated if the encapsidation efficiency of RRE-containing spliced HIV-vector transcripts is also increased by the viral Rev protein. Findings Starting with a lentiviral vector imitating the splicing pattern of HIV, we constructed vectors that express an unspliced transcript either identical in sequence to the singly-spliced or the fully-spliced RNA of the parental construct. After transfection of the different lentiviral vectors cytoplasmic and virion-associated RNA levels and vector titers were determined in the presence and absence of Rev. Rev enhanced the infectious titer of vectors containing an RRE 6 to 37-fold. Furthermore, Rev strongly increased encapsidation efficiencies of all RRE-containing transcripts up to 200-fold. However, a good correlation between encapsidation efficiency and lentiviral vector titer could only be observed for the gRNA. The infectious titer of the vector encoding the fully-spliced RNA without RRE as well as the encapsidation efficiency of all transcripts lacking the RRE was not influenced by Rev. Interestingly, the splicing process itself did not seem to interfere with packaging, since the encapsidation efficiencies of the same RNA expressed either by splicing or as an unspliced transcript did not differ significantly. Conclusions Rev-mediated nuclear export enhances the encapsidation efficiency of RRE-containing lentiviral vector RNAs independently of whether they have been spliced or not.
Artificial 64-Residue HIV-1 Enhancer-Binding Peptide Is a Potent Inhibitor of Viral Replication in HIV-1-Infected Cells
Mouhssin Oufir,Leslie R. Bisset,Stefan R. K. Hoffmann,Gongda Xue,Stephan Klauser,Bianca Bergamaschi,Alain Gervaix,Jürg B?ni,J?rg Schüpbach,Bernd Gutte
Advances in Virology , 2011, DOI: 10.1155/2011/165871
Abstract: An artificial HIV-1 enhancer-binding peptide was extended by nine consecutive arginine residues at the C-terminus and by the nuclear localization signal of SV40 large T antigen at the N-terminus. The resulting synthetic 64-residue peptide was found to bind to the two enhancers of the HIV-1 long terminal repeat, cross the plasma membrane and the nuclear envelope of human cells, and suppress the HIV-1 enhancer-controlled expression of a green fluorescent protein reporter gene. Moreover, HIV-1 replication is inhibited by this peptide in HIV-1-infected CEM-GFP cells as revealed by HIV-1 p24 ELISA and real-time RT-PCR of HIV-1 RNA. Rapid uptake of this intracellular stable and inhibitory peptide into the cells implies that this peptide may have the potential to attenuate HIV-1 replication in vivo. 1. Introduction Treatment of HIV-1 infection has made considerable progress. Nevertheless, all current therapeutic approaches have been hampered by viral resistance mutations, undesired side effects, and high treatment cost [1]. Therefore, additional concepts for inhibiting HIV-1 replication, particle assembly, and escape have been developed. One approach to interfere with HIV-1 infection at an early stage is to block viral entry. Enfuvirtide, a synthetic peptide already in clinical use corresponding to the conserved extramembranous sequence 643 to 678 of the HIV-1 envelope glycoprotein gp41, was found to prevent the conformational change of gp41 necessary for HIV-1 fusion with CD4+ cells [2, 3]. Other approaches include the construction of a highly colonizing Escherichia coli (E. coli) strain secreting HIV-1 gp41-hemolysin to block HIV fusion with target cells [4], the use of an interchain disulfide bond-stabilized trimeric 45-residue fusion peptide [5, 6] to inhibit the fusion of a large number of HIV isolates with target cells, and the inhibition of HIV-1 infection of CD4+ T cells by microbial HSP70 [7]. Similarly, the human monoclonal 5H/I1-BMV-D5 single-chain variable region fragment (scFv) antibody selected from phage-displayed libraries has been shown to bind to the N-terminal heptad repeat region of gp41 and thus inhibited the formation of fusion intermediates in vitro and the replication of diverse clinical isolates of HIV-1 [8]. In macaques, protection from vaginal challenge with simian human immunodeficiency virus was achieved by vaginally delivered inhibitors of virus-cell fusion; moreover, two small molecule inhibitors binding to viral gp120 and cellular CCR5, respectively, prevent receptor binding by gp120, and a 53-residue peptide containing the
A Survey of Control Structures for Reconfigurable Petri Nets  [PDF]
Julia Padberg, Kathrin Hoffmann
Journal of Computer and Communications (JCC) , 2015, DOI: 10.4236/jcc.2015.32002
Abstract: Software systems are increasingly executed in dynamic infrastructures. These infrastructures are dynamic as they are themselves subject to change as they support various applications that may or may not share some of the resources. Dynamic software systems become more and more important, but are difficult to handle. Modeling and simulating dynamic systems requires the representation of their processes and the system changes within one model. To that effect, reconfigurable Petri nets consist of a Petri net and a set of rules that can modify the Petri net. Their main feature is the capability to model complex coordination behavior in dynamically adapting infrastructures. The interplay of both levels of dynamic behavior requires a very precise description, so the specification when and which rules are to be applied plays a crucial role for the convenient use of reconfigurable nets. We differentiate several types of reconfigurable Petri nets and present a survey of control structure for these types, reconfigurable Petri nets. These control structures either concern the infrastructure, i.e., the rules and transformations or the system part, i.e., the firing behavior, or both. They are introduced by a short characterization and illustrated by examples. We state the results for various Petri net types and the tools supporting the different control structures.
Marijuana Use and Depressive Symptoms among Young People: Examining Unidirectional and Bidirectional Effects  [PDF]
John P. Hoffmann
Health (Health) , 2018, DOI: 10.4236/health.2018.108080
Abstract: Research suggests that the prevalence of marijuana use and depression are increasing in the United States. Although it is not entirely clear what accounts for these coincident trends, several studies have shown that these two health concerns are associated among young people. This study assessed four hypotheses regarding the association between marijuana use and depression: 1) whether marijuana use affects subsequent symptoms of depression; 2) whether depressive symptoms affect subsequent marijuana use; 3) whether they are associated in a bidirectional (reciprocal) manner; and 4) whether the association between the two is confounded by stressful life events. Using eight years of longitudinal data from the Family Wellness and Health Study, a fixed-effects regression model provided empirical support for the first hypothesis only, but not for the others. Future research should explore in greater detail why marijuana use may have a causal impact on experiences with depression among young people.
Regulation of Hepatic Paraoxonase-1 Expression
Bianca Fuhrman
Journal of Lipids , 2012, DOI: 10.1155/2012/684010
Abstract: Serum paraoxonase-1 (PON1) is a member of the paraoxonases family (PON1, PON2, and PON3). PON1 is synthesized and secreted by the liver, and in circulation it is associated with HDL. PON1 has antioxidative properties, which are associated with the enzyme’s capability to decrease oxidative stress in atherosclerotic lesions and to attenuate atherosclerosis development. Epidemiological evidence demonstrates that low PON1 activity is associated with increased risk of cardiovascular events and cardiovascular disease and is an independent risk factor for coronary artery disease. Therefore, pharmacological modulation of PON1 activity or PON1 gene expression could constitute a useful approach for preventing atherosclerosis. A primary determinant of serum PON1 levels is the availability of the enzyme for release by the liver, the principal site of PON1 production. Together with the enzyme secretion rate, enzymatic turnover, and protein stability, the level of PON1 gene expression is a major determinant of PON1 status. This paper summarizes recent progress in understanding the regulation of PON1 expression in hepatocytes. 1. Introduction The atherosclerotic lesion is dominated by accumulation of lipid peroxides along with the progression of early plaque development [1]. Serum paraoxonase-1 (PON1) is an HDL-associated lipolactonase, which is synthesized and secreted by the liver [2]. PON1 has antioxidative properties, which are associated with the enzyme’s capability to protect LDL [3], as well as HDL [4] from oxidation, to decrease macrophage oxidative status [5], to stimulate cholesterol efflux from macrophages [6], to decrease oxidative status in atherosclerotic lesions [7], and to attenuate atherosclerosis development. Immunohistochemical analysis has revealed accumulation of PON1 in the human atherosclerotic lesion as it progresses from fatty streak to advanced lesion [8]. Recently it was demonstrated that PON1 acts to reduce the oxidizing potency of lipids in atherosclerotic lesions, thus providing protection against oxidation [9]. Epidemiological evidence demonstrates that low PON1 activity is associated with increased risk of cardiovascular events [10] and is an independent risk factor for cardiovascular disease [11]. A variety of nongenetic factors have been shown to influence serum PON1 levels and activity. PON1 undergoes inactivation under oxidative stress and its activity is preserved by dietary antioxidants [12]. Moderate daily consumption of alcohol [13], vitamin C and E [14], wine [15], or pomegranate juice [16], increased serum levels of PON1 in
A no??o de psíquico na teoria do imaginário de Sartre
Spohr, Bianca;
Psicologia USP , 2011, DOI: 10.1590/S0103-65642011005000027
Abstract: the definition of psychology as a science and its object of study have been the focus of discussion throughout the development of this discipline. although psychologists recognize the importance of this discussion and have contributed to this ongoing debate, they still believe they are far from reaching a general consensus. thus, taking this situation into consideration, this study aims at presenting sartre’s theory of the imaginary as an instrument for the understanding of the psychic - psychology’s object of study. therefore, in order to attain this objective, this research analyzes sartre’s l’imaginaire and la transcendance de l’ego, for the study of the imagination and its correlate, the imaginary, presupposes the study of consciousness and its correlate, the psychic. we have concluded that sartre has offered important contributions for an understanding of the psychic because he reformulated the notion of image by means of the reconstitution of consciousness and the psychic and because he stated that the imagination is a type of autonomous consciousness which represents, in essence, the notion of liberty.
Schattenwirtschaft unter Palmen: Der touristisch informelle Sektor im Urlaubsparadies Patong, Thailand
Bianca Gantner
ASEAS : ?sterreichische Zeitschrift für Südostasienwissenschaften , 2011,
Abstract: Seit den 1960er-Jahren spielt der Tourismussektor innerhalb der thail ndischen Wirtschaft eine wichtige Rolle und ist durch ein stetiges Wachstum gekennzeichnet. Für über 50 Prozent der Personen, die in Thailand ihren Lebensunterhalt durch informelle Besch ftigung (Schattenwirtschaft) sichern, stellt dieser boomende Sektor eine bedeutende Verdienstquelle dar. Unter Verwendung qualitativer Methoden (Interviews und teilnehmende Beobachtung) untersucht dieser Artikel den touristisch informellen Sektor des Ortes Patong auf der Insel Phuket und stellt sowohl die Entstehung und den Verlauf als auch die Akteurs- und Angebotsstruktur dieses Sektors dar. Die aktuelle Entwicklung wird dabei verglichen mit dem Modell Vorlaufers, das die Entwicklung einer staatlich gef rderten Tourismusdestination beschreibt. Entgegen der Annahme dieses Modells, mit einem Wachstum des Tourismussektors würde der Anteil an formeller gegenüber der informellen Besch ftigung steigen, zeigt sich, dass kein Rückgang des touristisch informellen Sektors zu erkennen ist, dieser weiterhin ein integraler Bestandteil der Tourismuswirtschaft Patongs geblieben ist und eine wichtige Verdienstquelle für MigrantInnen und die lokale Bev lkerung darstellt. --- Since the 1960s, tourism has become a vital part of the Thai economy and has been characterised by a steady growth. For more than 50 percent of all Thais working in the informal sector (shadow economy), the booming tourism industry represents an important source of income. In this article Patong on Phuket serves as a case study for examining the network of actors, the touristic supply structure as well as its evolution and developments over the years by using qualitative methods (interviews and participant observation). The empirical data will then be compared to Vorlaufer’s scheme on the development of a state-sponsored tourist destination. In contrast to the scheme’s assumption of a decline of the informal and a rise of the formal sector, the empirical results show that the level of informal activity remains on a high level and can be described as an integral part of Patong’s tourism industry. In addition, revenues from the informal sector serve as an important source of income for migrants and locals.
An existence and uniqueness theorem to the Cauchy problem for thermostatted-KTAP models
C. Bianca
International Journal of Mathematical Analysis , 2012,
The Sleep of the Sultan. Rewriting of the Mille et une nuits in eighteenth-century contes exotiques Il sonno del sultano. Riscrittura delle Mille et une nuits nei contes exotiques settecenteschi
Bianca Gai
Between , 2011,
Abstract: This paper analyses the influence of Galland's Les Mille et une nuits on two Eighteenth Century French tales: Crébillon's Le Sopha and Diderot's L'Oiseau blanc, conte bleu. The focus is the use of Galland's narrative structure by French conte philosophique. Particularly, Crébillon's and Diderot's tales inherit from Galland's work the topic of the "asleep sultan". If in Les Mille et une nuits the narrative voice has the function to keep the listener awake, Crébillon and Diderot overturn the link between speaker and listener, as their narrative voices induce on the contrary sleep on the listener. This overturning is considered here as a consequence of these writers' theory of literature and philosophy. Il contributo analizza l'influenza della raccolta Les Mille et une nuits di Galland su due racconti francesi del XVIII secolo: Le Sopha di Crébillon e L'oiseau blanc conte bleu di Diderot. Oggetto di indagine è l'uso della struttura narrativa di Galland nel "conte philosophique" francese. In particolare, i racconti di Crébillon e Diderot ereditano dall'opera di Galland il tema del "sultano addormentato". Se nelle Mille et une nuits la voce narrativa ha la funzione di tenere sveglio l'ascoltatore, Crébillon e Diderot rovesciano la relazione tra parlante e ascoltatore, in quanto loro voci narranti inducono al contrario il sonno dell'ascoltatore. Tale rovesciamento è considerato qui una conseguenza della teoria della letteratura e della concezione filosofica dei due scrittori.
La presenza greca in Italia alla fine del XV secolo
Concetta Bianca
Studi Slavistici , 2011,
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