Epstein-Barr virus: clinical and epidemiological revisits and genetic basis of oncogenesis

Epstein-Barr virus (EBV) is classified as a member in the order herpesvirales, family herpesviridae, subfamily gammaherpesvirinae and the genus lymphocytovirus. The virus is an exclusively human pathogen and thus also termed as human herpesvirus 4 (HHV4). It was the first oncogenic virus recognized and has been incriminated in the causation of tumors of both lymphatic and epithelial nature. It was reported in some previous studies that 95% of the population worldwide are serologically positive to the virus. Clinically, EBV primary infection is almost silent, persisting as a life-long asymptomatic latent infection in B cells although it may be responsible for a transient clinical syndrome called infectious mononucleosis. Following reactivation of the virus from latency due to immunocompromised status, EBV was found to be associated with several tumors. EBV linked to oncogenesis as detected in lymphoid tumors such as Burkitt's lymphoma (BL), Hodgkin's disease (HD), post-transplant lymphoproliferative disorders (PTLD) and T-cell lymphomas (e.g. Peripheral T-cell lymphomas; PTCL and Anaplastic large cell lymphomas; ALCL). It is also linked to epithelial tumors such as nasopharyngeal carcinoma (NPC), gastric carcinomas and oral hairy leukoplakia (OHL). In vitro, EBV many studies have demonstrated its ability to transform B cells into lymphoblastoid cell lines (LCLs). Despite these malignancies showing different clinical and epidemiological patterns when studied, genetic studies have suggested that these EBV- associated transformations were characterized generally by low level of virus gene expression with only the latent virus proteins (LVPs) upregulated in both tumors and LCLs. In this review, we summarize some clinical and epidemiological features of EBV- associated tumors. We also discuss how EBV latent genes may lead to oncogenesis in the different clinical malignancie

Shell-dependent hole transport in highly luminescent CdSe-core CdS/ZnCdS/ZnS multi-shell nanocrystals

The photoinduced hole transfer dynamics from CdSe quantum dots (QDs), shelled with ZnS or CdS/CdZnS/ZnS layers, to organic hole transporting materials (HTMs) is investigated by absorption, steady-state and time-resolved photoluminescence (PL) spectroscopy. The PL intensity and lifetime of the QDs are dramatically quenched when HTMs are added into the dilute QD solution. The quenching efficiency of the QDs significantly decreases with increasing the shell thickness and increases with decreasing the oxidation potential of the HTMs. These facts are correlated with the photoinduced hole transfer from the QDs to the HTMs. The above results are helpful in understanding the photoexcitation dynamics-related phenomena of organic molecule conjugated nano-object

Structure Property Relationship of Micellar Waterborne Poly(Urethane-Urea): Tunable Mechanical Properties and Controlled Release Profiles with Amphiphilic Triblock Copolymers

Waterborne polyurethane (WPU) has attracted significant interest as a promising alternative to solvent-based polyurethane (SPU) due to its positive impact on safety and sustainability. However, significant limitations of WPU, such as its weaker mechanical strength, limit its ability to replace SPU. Triblock amphiphilic diols are promising materials to enhance the performance of WPU due to their well-defined hydrophobic-hydrophilic structures. Yet, our understanding of the relationship between the hydrophobic-hydrophilic arrangements of triblock amphiphilic diols and the physical properties of WPU remains limited. In this study, we show that by controlling the micellar structure of WPU in aqueous solution via the introduction of triblock amphiphilic diols, the postcuring efficiency and the resulting mechanical strength of WPU can be significantly enhanced. Small-angle neutron scattering confirmed the microstructure and spatial distribution of hydrophilic and hydrophobic segments in the engineered WPU micelles. In addition, we show that the control of the WPU micellar structure through triblock amphiphilic diols renders WPU attractive in the applications of controlled release, such as drug delivery. Here, curcumin was used as a model hydrophobic drug, and the drug release behavior from WPU-micellar-based drug delivery systems was characterized. It was found that curcumin-loaded WPU drug delivery systems were highly biocompatible and exhibited antibacterial properties in vitro. Furthermore, the sustained release profile of the drug was found to be dependent on the structure of the triblock amphiphilic diols, suggesting the possibility of controlling the drug release profile via the selection of triblock amphiphilic diols. This work shows that by shedding light on the structure-property relationship of triblock amphiphilic diol-containing WPU micelles, we may enhance the applicability of WPU systems and move closer to realizing their promising potential in real-life applications.ChemE/Product and Process EngineeringRID/TS/Instrumenten groe

Higgs Boson Studies at the Tevatron

We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90--200 GeV$/c^2$ produced in the gluon-gluon fusion, $WH$, $ZH$, $t{\bar{t}}H$, and vector boson fusion processes, and decaying in the $H\rightarrow b{\bar{b}}$, $H\rightarrow W^+W^-$, $H\rightarrow ZZ$, $H\rightarrow\tau^+\tau^-$, and $H\rightarrow \gamma\gamma$ modes. The data correspond to integrated luminosities of up to 10 fb$^{-1}$ and were collected at the Fermilab Tevatron in $p{\bar{p}}$ collisions at $\sqrt{s}=1.96$ TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV/$c^2$. The local significance corresponds to 3.0 standard deviations at $m_H=125$ GeV/$c^2$, consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for $H \to b\bar{b}$, $H \to W^+W^-$, $H\rightarrow\tau^+\tau^-$, and $H\rightarrow\gamma\gamma$. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125 GeV/$c^2$

Expressão gênica nos estigmas e estiletes de plantas da família Solanaceae: seqüências relacionadas com a patogênese Gene expression in Solanaceae stigmas and styles: pathogenesis related sequences

O florescimento é uma mudança fundamental no desenvolvimento das plantas. A evocação do florescimento é a transição entre a fase vegetativa e a reprodutiva, durante a qual ocorre a especialização dos meristemas apicais. Nas plantas com flores completas, como aquelas da família Solanaceae, células meristemáticas na camada mais externa, dão origem às sépalas e aquelas na segunda camada originam as pétalas; na terceira camada, as células tornam-se estames e aquelas na quarta e mais interna camada dão origem aos carpelos (ovários, estiletes e estigmas). O surgimento desses órgãos florais é relativamente recente na história evolutiva das plantas e demandou o desenvolvimento de padrões de expressão tecido-específicos. Um desses padrões específicos, em flores de Solanaceae, inclui a expressão de genes relacionados com os processos de defesa, cuja atividade é induzida por infecção com patógenos ou por ferimentos nos órgãos vegetativos da planta, mas que são constitutivamente expressos nas flores sadias, onde os transcritos se acumulam seguindo padrões vinculados ao desenvolvimento. Neste trabalho, são revistas e compiladas as informações publicadas sobre os genes relacionados com as reações de defesa, denominados Sp41, PR10a, SK2 e sobre uma adenosina-metiltransferase, que também pode estar relacionada com a reação aos patógenos, e que seguem esse modelo de expressão. Algumas das hipóteses existentes para explicar este modelo também são apresentadas.<br>Flowering is a fundamental process in plant development. Flower evocation is the transition from the vegetative to the reproductive phase, when the specialization of apical meristems takes place. In plants, such as the Solanaceae, which present complete flowers, the meristematic cells in the most external first series bring out the sepals and those cells in the second series turn to be the petals; in the third series the cells become stamens and the cells in the innermost series give origin to carpels (ovaries, styles and stigmas). Floral organs have shown up recently in evolution and this event demanded the development of tissue-specific patterns for gene expression. Indeed, some of the pathogenesis related genes from Solanaceae, induced by infection or wounding in vegetative organs, show flower-specific patterns of transcription, with constitutive expression and the occurrence of temporal profiles of expression controlled by development being detected in healthy floral tissues. PR10a, SK2, Sp41 pathogenesis related genes and an adenosine:methyltransferase, possibly related to pathogenesis as well, are genes that follow the described tissue-specific patterns and are reviewed here. Hypothesis proposed to demonstrate the meanings of these mechanisms of gene expression are also presented