Experimental Realization of Dicke States of up to Six Qubits for Multiparty Quantum Networking

We report the first experimental generation and characterization of a six-photon Dicke state. The produced state shows a fidelity of F=0.56 +/- 0.02 with respect to an ideal Dicke state and violates a witness detecting genuine six-qubit entanglement by 4 standard deviations. We confirm characteristic Dicke properties of our resource and demonstrate its versatility by projecting out four- and five-photon Dicke states, as well as four-photon Greenberger-Horne-Zeilinger and W states. We also show that Dicke states have interesting applications in multiparty quantum networking protocols such as open-destination teleportation, telecloning, and quantum secret sharing.

PARP inhibition induces BAX/BAK-independent synthetic lethality of BRCA1-deficient non-small cell lung cancer

Evasion of apoptosis contributes to both tumourigenesis and drug resistance in non-small cell lung carcinoma (NSCLC). The pro-apoptotic BCL-2 family proteins BAX and BAK are critical regulators of mitochondrial apoptosis. New strategies for targeting NSCLC in a mitochondria-independent manner should bypass this common mechanism of apoptosis block. BRCA1 mutation frequency in lung cancer is low; however, decreased BRCA1 mRNA and protein expression levels have been reported in a significant proportion of lung adenocarcinomas. BRCA1 mutation/deficiency confers a defect in homologous recombination DNA repair that has been exploited by synthetic lethality through inhibition of PARP (PARPi) in breast and ovarian cells; however, it is not known whether this same synthetic lethal mechanism exists in NSCLC cells. Additionally, it is unknown whether the mitochondrial apoptotic pathway is required for BRCA1/PARPi-mediated synthetic lethality. Here we demonstrate that silencing of BRCA1 expression by RNA interference sensitizes NSCLC cells to PARP inhibition. Importantly, this sensitivity was not attenuated in cells harbouring mitochondrial apoptosis block induced by co-depletion of BAX and BAK. Furthermore, we demonstrate that BRCA1 inhibition cannot override platinum resistance, which is often mediated by loss of mitochondrial apoptosis signalling, but can still sensitize to PARP inhibition. Finally we demonstrate the existence of a BRCA1-deficient subgroup (11-19%) of NSCLC patients by analysing BRCA1 protein levels using immunohistochemistry in two independent primary NSCLC cohorts. Taken together, the existence of BRCA1-immunodeficient NSCLC suggests that this molecular subgroup could be effectively targeted by PARP inhibitors in the clinic and that PARP inhibitors could be used for the treatment of BRCA1-immunodeficient, platinum-resistant tumours. Copyright (C) 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The long-term impacts of fisheries on epifaunal assemblage function and structure, in a special area of conservation

Fisheries can have profound effects on epifaunal community function and structure. We analysed the results from five dive surveys (1975–1976, 1980, 1983, 2003 and 2007), taken in a Special Area of Conservation, Strangford Lough, Northern Ireland before and after a ten year period of increased trawling activity between 1985 and 1995. There were no detectable differences in the species richness or taxonomic distinctiveness before (1975–1983) and after (2003–2007) this period. However, there was a shift in the epifaunal assemblage between the surveys in 1975–1983 and 2003–2007. In general, the slow-moving, or sessile, erect, filterfeeders were replaced by highly mobile, swimming, scavengers and predators. There were declines in the frequency of the fished bivalve Aequipecten opercularis and the non-fished bivalves Modiolus modiolus and Chlamys varia and some erect sessile invertebrates between the surveys in 1975–1983 and 2003–2007. In contrast, there were increases in the frequency of the fished and reseeded bivalves Pecten maximus and Ostrea edulis, the fished crabs Cancer pagurus and Necora puber and the non-fished sea stars Asterias rubens, Crossaster papposus and Henricia oculata between the surveys in 1975–1983 and 2003–2007. We suggest that these shifts could be directly and indirectly attributed to the long-termimpacts of trawl fishing gear, although increases in the supply of discarded bait and influxes of sediment may also have contributed to changes in the frequency of some taxa. These results suggest that despite their limitations, historical surveys and repeat sampling over long periods can help to elucidate the inferred patterns in the epifaunal community. The use of commercial fishing gear was banned from two areas in Strangford Lough in 2011, making it a model ecosystem for assessing the long-term recovery of the epifaunal community from the impacts of mobile and pot fishing gear.

Heat shock protein 90 inhibition is cytotoxic to primary AML cells expressing mutant FLT3 and results in altered downstream signalling

Activating mutations of the FMS-like tyrosine kinase 3 gene (FLT3) occur in approximately one-third of patients with acute myeloid leukaemia (AML) and predict for a poor outcome. Heat shock protein 90 (Hsp90) is a molecular chaperone that is frequently used by cancer cells to stabilise mutant oncoproteins. Mutant FLT3 is chaperoned by Hsp90 in primary AML blasts whereas unmutated FLT3 is not, making Hsp90 inhibitors potentially useful therapeutically. The present study showed that inhibition of Hsp90 by 17-allylamino-17-demethoxygeldanamycin (17-AAG) was cytotoxic to primary AML cells expressing mutant FLT3. Inhibition of Hsp90 results in altered downstream signalling effects in primary AML cells with disruption of Janus kinase-signal transducer and activator of transcription (JAK-STAT), mitogen-activated protein kinase and phosphatidylinositol 3/AKT signalling pathways. Co-treatment of blasts with 17-AAG and cytarabine resulted in a synergistic or additive effect in approximately 50% of AML cases tested. Our results confirm that Hsp90 is a valid molecular target in the therapy of AML. Inhibition of Hsp90 in parallel with conventional AML therapies may have particular benefit in those patients with the poor prognostic FLT3 mutant disease.

FUS expression alters the differentiation response to all-trans retinoic acid in NB4 and NB4R2 cells

The FUS gene is overexpressed in acute myeloid leukaemia (AML) patients and has roles in transcription and mRNA processing. We used ectopic expression of FUS and FUS antisense sequences to assess the effect of modulation of FUS expression in all-trans retinoic acid (ATRA)-sensitive (NB4) and insensitive (NB4R2) human acute promyelocytic (APL) cell lines which express the t(15:17) translocation. Growth, viability and differentiation patterns were maintained, but the expression of the FUS antisense construct in both the cell lines altered the response to ATRA: the previously ATRA-sensitive NB4 cells exhibited resistance; whilst the previously resistant NB4R2 cells showed a differentiation response to treatment.

Phosphoramidates of 2'-beta-D-arabinouridine (AraU) as phosphate prodrugs; design, synthesis, in vitro activity and metabolism

2'-Beta-D-arabinouridine (AraU), the uridine analogue of the anticancer agent AraC, was synthesized and evaluated for antiviral activity and cytotoxicity. In addition, a series of AraU monophosphate prodrugs in the form of triester phosphoramidates (ProTides) were also synthesized and tested against a range of viruses, leukaemia and solid tumour cell lines. Unfortunately, neither the parent compound (AraU) nor any of its ProTides showed antiviral activity, nor potent inhibitory activity against any of the cancer cell lines. Therefore, the metabolism of AraU phosphoramidates to release AraU monophosphate was investigated. The results showed carboxypeptidase Y, hog liver esterase and crude CEM tumor cell extracts to hydrolyse the ester motif of phosphoramidates with subsequent loss of the aryl group, while molecular modelling studies suggested that the AraU l-alanine aminoacyl phosphate derivative might not be a good substrate for the phosphoramidase enzyme Hint-1. These findings are in agreement with the observed disappearance of intact prodrug and concomitant appearance of the corresponding phosphoramidate intermediate derivative in CEM cell extracts without measurable formation of araU monophosphate. These findings may explain the poor antiviral/cytostatic potential of the prodrugs.

Chemically engineering ligand selectivity at the free fatty acid receptor 2 based on pharmacological variation between species orthologs

When it is difficult to develop selective ligands within a family of related G-protein-coupled receptors (GPCRs), chemically engineered receptors activated solely by synthetic ligands (RASSLs) are useful alternatives for probing receptor function. In the present work, we explored whether a RASSL of the free fatty acid receptor 2 (FFA2) could be developed on the basis of pharmacological variation between species orthologs. For this, bovine FFA2 was characterized, revealing distinct ligand selectivity compared with human FFA2. Homology modeling and mutational analysis demonstrated a single mutation in human FFA2 of C4.57G resulted in a human FFA2 receptor with ligand selectivity similar to the bovine receptor. This was exploited to generate human FFA2-RASSL by the addition of a second mutation at a known orthosteric ligand interaction site, H6.55Q. The resulting FFA2-RASSL displayed a >100-fold loss of activity to endogenous ligands, while responding to the distinct ligand sorbic acid with pEC(50) values for inhibition of cAMP, 5.83 ± 0.11; Ca(2+) mobilization, 4.63 ± 0.05; ERK phosphorylation, 5.61 ± 0.06; and dynamic mass redistribution, 5.35 ± 0.06. This FFA2-RASSL will be useful in future studies on this receptor and demonstrates that exploitation of pharmacological variation between species orthologs is a powerful method to generate novel chemically engineered GPCRs.-Hudson, B. D., Christiansen, E., Tikhonova, I. G., Grundmann, M., Kostenis, E., Adams, D. R., Ulven, T., Milligan, G. Chemically engineering ligand selectivity at the free fatty acid receptor 2 based on pharmacological variation between species orthologs.

Selective Orthosteric Free Fatty Acid Receptor 2 (FFA2) Agonists IDENTIFICATION OF THE STRUCTURAL AND CHEMICAL REQUIREMENTS FOR SELECTIVE ACTIVATION OF FFA2 VERSUS FFA3

Free fatty acid receptor 2 (FFA2; GPR43) is a G protein-coupled seven-transmembrane receptor for short-chain fatty acids (SCFAs) that is implicated in inflammatory and metabolic disorders. The SCFA propionate has close to optimal ligand efficiency for FFA2 and can hence be considered as highly potent given its size. Propionate, however, does not discriminate between FFA2 and the closely related receptor FFA3 (GPR41). To identify FFA2-selective ligands and understand the molecular basis for FFA2 selectivity, a targeted library of small carboxylic acids was examined using holistic, label-free dynamic mass redistribution technology for primary screening and the receptor-proximal G protein [S-35] guanosine 5'-(3-O-thio) triphosphate activation, inositol phosphate, and cAMP accumulation assays for hit confirmation. Structure-activity relationship analysis allowed formulation of a general rule to predict selectivity for small carboxylic acids at the orthosteric binding site where ligands with substituted sp(3)-hybridized alpha-carbons preferentially activate FFA3, whereas ligands with sp(2)- or sp-hybridized alpha-carbons prefer FFA2. The orthosteric binding mode was verified by site-directed mutagenesis: replacement of orthosteric site arginine residues by alanine in FFA2 prevented ligand binding, and molecular modeling predicted the detailed mode of binding. Based on this, selective mutation of three residues to their non-conserved counterparts in FFA3 was sufficient to transfer FFA3 selectivity to FFA2. Thus, selective activation of FFA2 via the orthosteric site is achievable with rather small ligands, a finding with significant implications for the rational design of therapeutic compounds selectively targeting the SCFA receptors.

Emergence time and foraging activity in Pallas' mastiff bat, Molossus molossus (Chiroptera: Molossidae) in relation to sunset/sunrise and phase of the moon

The decision on when to emerge from the safety of a roost and forage for prey is thought to be a result of the trade off between peak insect abundance and predation pressure for bats. In this study we show that the velvety free-tailed bat Molossus molossus emerges just after sunset and just before sunrise for very short foraging bouts (average 82.2 min foraging per night). Contrary to previous studies, bats remain inactive in their roost between activity patterns. Activity was measured over two complete lunar cycles and there was no indication that phase of the moon had an influence on emergence time or the numbers of bats that emerged from the roost. This data suggests that M. molossus represents an example of an aerial hawking bat whose foraging behaviour is in fact adapted to the compromise between the need to exploit highest prey availability and the need to avoid predation.

Steroid injection for inferior heel pain: a randomised controlled trial

BACKGROUND:

Plantar fasciitis is a common cause of heel pain. The aim of this study was twofold: to compare steroid injection with placebo injection and to compare ultrasound guided with unguided steroid injection in the management of this condition.

METHODS:

65 patients with inferior heel pain were recruited between November 2008 and June 2011. Heel pain was measured using a visual analogue scale (VAS) at baseline and follow-up 6 and 12 weeks after injection.

RESULTS:

22 patients were randomised to ultrasound guided steroid injection, 21 patients to palpation guided steroid injection and 22 to ultrasound guided placebo injection. There was a significant difference in VAS scores between the groups at 6 and 12 weeks (p=0.018 and p=0.004, respectively). There was a 19.7 (95% CI 2.5 to 37.0) difference in mean VAS scores at 6 weeks between the ultrasound guided steroid group and the placebo group and a 24.0 (95% CI 6.6 to 41.3) difference between the unguided steroid group and the placebo group at 6 weeks. At 12 weeks, the mean difference was 25.1 (95% CI 6.5 to 43.6) and 28.4 (95% CI 11.1 to 45.7) respectively between both steroid injection groups and the placebo group. There was no difference in VAS scores following steroid injection between the ultrasound guided and the unguided groups at either time point. Plantar fascia thickness was significantly reduced after injection in both active treatment groups (p=0.00).

CONCLUSIONS:

In this study, steroid injection showed a clear benefit over placebo at 6 weeks and this difference was maintained at 12 weeks.Trial Registration No ISRCTN79628180 (www.controlled-trials.com).

Progressive lung cancer determined by expression profiling and transcriptional regulation

Clinically, our ability to predict disease outcome for patients with early stage lung cancer is currently poor. To address this issue, tumour specimens were collected at surgery from non-small cell lung cancer (NSCLC) patients as part of the European Early Lung Cancer (EUELC) consortium. The patients were followed-up for three years post-surgery and patients who suffered progressive disease (PD, tumour recurrence, metastasis or a second primary) or remained disease-free (DF) during follow-up were identified. RNA from both tumour and adjacent-normal lung tissue was extracted from patients and subjected to microarray expression profiling. These samples included 36 adenocarcinomas and 23 squamous cell carcinomas from both PD and DF patients. The microarray data was subject to a series of systematic bioinformatics analyses at gene, network and transcription factor levels. The focus of these analyses was 2-fold: firstly to determine whether there were specific biomarkers capable of differentiating between PD and DF patients, and secondly, to identify molecular networks which may contribute to the progressive tumour phenotype. The experimental design and analyses performed permitted the clear differentiation between PD and DF patients using a set of biomarkers implicated in neuroendocrine signalling and allowed the inference of a set of transcription factors whose activity may differ according to disease outcome. Potential links between the biomarkers, the transcription factors and the genes p21/CDKN1A and Myc, which have previously been implicated in NSCLC development, were revealed by a combination of pathway analysis and microarray meta-analysis. These findings suggest that neuroendocrine-related genes, potentially driven through p21/CDKN1A and Myc, are closely linked to whether or not a NSCLC patient will have poor clinical outcome.