Corey-Chaykovsky epoxidation of twisted amides: Synthesis and reactivity of bridged spiro-epoxyamines

The first example of a Corey-Chaykovsky epoxidation employing amides as substrates is described. Medium-bridged twisted amides serve as precursors to a family of isolable aminoepoxides. The reactivity of bridged spiro-epoxyamines is also investigated

Real Time Global Tests of the ALICE High Level Trigger Data Transport Framework

The High Level Trigger (HLT) system of the ALICE experiment is an online event filter and trigger system designed for input bandwidths of up to 25 GB/s at event rates of up to 1 kHz. The system is designed as a scalable PC cluster, implementing several hundred nodes. The transport of data in the system is handled by an object-oriented data flow framework operating on the basis of the publisher-subscriber principle, being designed fully pipelined with lowest processing overhead and communication latency in the cluster. In this paper, we report the latest measurements where this framework has been operated on five different sites over a global north-south link extending more than 10,000 km, processing a ``real-time'' data flow.Comment: 8 pages 4 figure

In vitro selection of RNA aptamers against a composite small molecule-protein surface

A particularly challenging problem in chemical biology entails developing systems for modulating the activity of RNA using small molecules. One promising new approach towards this problem exploits the phenomenon of ‘surface borrowing,’ in which the small molecule is presented to the RNA in complex with a protein, thereby expanding the overall surface area available for interaction with RNA. To extend the utility of surface borrowing to include potential applications in synthetic biology, we set out to create an ‘orthogonal’ RNA-targeting system, one in which all components are foreign to the cell. Here we report the identification of small RNA modules selected in vitro to bind a surface-engineered protein, but only when the two macromolecules are bound to a synthetic bifunctional small molecule

Proximity effects in nucleophilic addition reactions to medium-bridged twisted lactams: Remarkably stable tetrahedral intermediates

The reactions of a series of strained bicyclic and tricyclic one-carbon bridged lactams with organometallic reagents have been investigated. These amides permit isolation of a number of remarkably stable hemiaminals upon nucleophilic addition to the twisted amide bonds present in the lactam precursors. The factors that affect the stability of the resulting bridged hemiaminals are presented. In some cases, the hemiaminals were found to collapse to the open-form amino ketones in a manner expected for traditional carboxylic acid derivatives. Transannular N · · · C=O interactions were also observed in some nine-membered amino ketones. Additionally, tricyclic bridged lactams were found to react with some nucleophiles that typically react with ketones but not with planar amides. The effect of geometry on the reactivity of amide bonds and the amide bond distortion range that marks the boundary of amide-like and ketone-like carbonyl reactivity of lactams are also discussed

WNT5A gene and protein expression in endometrial cancer

Introduction. WNT5A (Wnt family member 5A) belongs to the WNT family of secreted signaling glycoproteins that play essential role in developmental, physiological and pathological processes. WNT5A was shown to take part in carcinogenesis process playing both oncogenic and suppressor functions in various types of human malignancies. This study aimed to assess the expression of the WNT5A gene at the mRNA and protein levels in the specimens derived from endometrial cancer (EC) or unchanged control endometrium. The associations between the WNT5A expression levels and clinicopathological characteristics and survival of EC patients were evaluated. Materials and methods. Total RNA was isolated in order to assess the relative amounts of WNT5A mRNA by quantitative polymerase chain reaction (QPCR) in samples of unchanged endometrial control (n = 8) and tumor samples of EC patients (n = 28). Immunohistochemistry (IHC) was used to determine the presence of WNT5A protein in the sections of formalin-fixed, paraffin-embedded tissue specimens derived from unchanged endome­trial controls (n = 6) and EC tumors (n = 19). Significance of differences in WNT5A expression levels between the studied groups of EC patients and correlations between the WNT5A and demographic data, pathological features, hematological parameters and overall survival of the patients were evaluated by statistical analysis. Results. The level of WNT5A mRNA was decreased in EC in comparison to unchanged endometrium. WNT5A expression was associated with primary tumor invasion status exhibiting reduced level of transcripts in EC that involved organs beyond the uterus when compared to the uterus-confined cancers. WNT5A immunoreactivity was visualized in the cytoplasm and nuclei of EC cells as well as in the luminal and glandular epithelial cells of unchanged endometrium. WNT5A mRNA expression levels correlated negatively with cytoplasmic, and positively with nuclear immunoreactivity of the WNT5A protein in the EC cells. In addition, the relationships between blood leucocyte count (in particular granulocytes and lymphocytes) of patients with EC and their WNT5A mRNA and protein expression levels were established. A positive correlation between the nuclear immunoexpression of WNT5A protein in the cancer cells in cell nuclei and mean platelet volume in blood was also found. Conclusions. The results of the first study of WNT5A expression at the transcript and protein levels indicate that it could be considered as a potential marker of molecular changes that take place during EC development

Selection for Replicases in Protocells

PMCID: PMC3649988This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Electrostatically gated membrane permeability in inorganic protocells

Although several strategies are now available to produce functional microcompartments analogous to primitive cell-like structures, little progress has been made in generating protocell constructs with self-controlled membrane permeability. Here we describe the preparation of water-dispersible colloidosomes based on silica nanoparticles and delineated by a continuous semipermeable inorganic membrane capable of self-activated, electrostatically gated permeability. We use crosslinking and covalent grafting of a pH-responsive copolymer to generate an ultrathin elastic membrane that exhibits selective release and uptake of small molecules. This behaviour, which depends on the charge of the copolymer coronal layer, serves to trigger enzymatic dephosphorylation reactions specifically within the protocell aqueous interior. This system represents a step towards the design and construction of alternative types of artificial chemical cells and protocell models based on spontaneous processes of inorganic self-organization

THE CC1 PROJECT – SYSTEM FOR PRIVATE CLOUD COMPUTING

The main features of the Cloud Computing system developed at IFJ PAN are described. The project is financed from the structural resources provided by the European Commission and the Polish Ministry of Science and Higher Education (Innovative Economy, National Cohesion Strategy). The system delivers a solution for carrying out computer calculations on a Private Cloud computing infrastructure. It consists of an intuitive Web based user interface, a module for the users and resources administration and the standard EC2 interface implementation. Thanks to the distributed character of the system it allows for the integration of a geographically distant federation of computer clusters within a uniform user environment

Structural characterization of N-protonated amides: Regioselective N-activation of medium-bridged twisted lactams

The straightforward protonation of lactams by treatment with acid and the full structural characterization of three resulting N-protonated lactams are disclosed. This work provides experimental evidence that N-protonation of amide bonds results in a dramatic increase in nonplanarity about the C-N amide bond. The resulting compounds are discussed in structural, spectroscopic, and reactivity terms. The data suggest that distortion of these amide bonds by -50° is sufficient for their effective N-activation