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By suppressing gene transcription through the recruitment of corepressor proteins, B-cell lymphoma 6 (BCL6) protein controls a transcriptional network required for the formation and maintenance of B-cell germinal centres. As BCL6 deregulation is implicated in the development of Diffuse Large B-Cell Lymphoma, we sought to discover novel small molecule inhibitors that disrupt the BCL6-corepressor protein–protein interaction (PPI). Here we report our hit finding and compound optimisation strategies, which provide insight into the multi-faceted orthogonal approaches that are needed to tackle this challenging PPI with small molecule inhibitors. Using a 1536-well plate fluorescence polarisation high throughput screen we identified multiple hit series, which were followed up by hit confirmation using a thermal shift assay, surface plasmon resonance and ligand-observed NMR. We determined X-ray structures of BCL6 bound to compounds from nine different series, enabling a structure-based drug design approach to improve their weak biochemical potency. We developed a time-resolved fluorescence energy transfer biochemical assay and a nano bioluminescence resonance energy transfer cellular assay to monitor cellular activity during compound optimisation. This workflow led to the discovery of novel inhibitors with respective biochemical and cellular potencies (IC50s) in the sub-micromolar and low micromolar range.

Introduction/Background Aims - To evaluate impact on sexual function, endocrine function, quality-of-life (QoL), health and well-being and determine cost-effectiveness of risk-reducing early-salpingectomy and delayed oophorectomy (RRESDO), as a two-step ovarian cancer (OC) prevention strategy in pre-menopausal women at increased risk of OC. Methodology Design - Multi-centre, observational cohort controlled trial with three arms: RRESDO; risk-reducing salpingo-oophorectomy (RRSO); controls (no surgery). Inclusion-criteria: Pre-menopausal women; >30-years; at increased risk of OC (mutation carriers or on basis of a strong family-history; completed their family (for surgical arms). Exclusion-criteria: Post-menopausal women; previous bilateral salpingectomy or bilateral oophorectomy; pregnancy; previous tubal/ovarian/peritoneal malignancy; Recruitment: Through NHS cancer genetics/high-risk familial cancer clinics/general gynaecology clinics/gynaecological oncology clinics/GP surgeries/clinical referrals/supporting charities/self-referral. Primary-outcome: Sexual function. Secondary-outcomes: Endocrine function/menopause; regret/satisfaction; surgical morbidity; QoL/psychological health; number of intraepithelial carcinomas/invasive cancers; utility scores for early-salpingectomy; cost-effectiveness; health and well-being. Consenting individuals for the surgical arms undergo an ultrasound, CA125, FSH and complete questionnaires collecting information on medical history, family-history, QoL, sexual function, cancer worry, psychological well-being and satisfaction/regret. All women undergoing surgery have cytological and histological assessment using a SEE-FIMM protocol, with centralised pathology review. Post-surgery FSH levels are tested and follow-up questionnaires sent at 3 months and annually. Controls have FSH levels checked and complete questionnaires at baseline and annually for three years. Participants from all three arms are invited to take part in semi-structured in-depth interviews. Results PROTECTOR is open to recruitment across several centres throughout the UK. Conclusion With growing evidence implicating the role of the fallopian tubes in ovarian carcinogenesis and the detrimental sequelae of surgical menopause in pre-menopausal women following RRSO, PROTECTOR is essential to investigate RRESDO as an alternative risk-reducing strategy in women who do not wish to undergo oophorectomy. Disclosure RM declares research funding from Barts and The London Charity and Roseetrees Trust for the PROTECTOR Study and is Chief Investigator. RM declares research funding from The Eve Appeal and Cancer Research UK outside this work, as well as an honorarium for grant review from Israel National Institute for Health Policy Research. RM is supported by an NHS Innovation Accelerator (NIA) Fellowship for population testing. FG is an investigator and the study coordinator for the PROTECTOR study. UM has a financial interest in Abcodia Ltd., a company formed to develop academic and commercial development of biomarkers for screening and risk prediction. NS, GM, NW, RG, GR, GB are members of the PROTECTOR central pathology review committee. GE, ES, HH, UM are members of the PROTECTOR trial management committee. MB, RL have nothing to declare.

Background Health literacy is gaining increasing attention as a means of promoting individual- community- and population-level health, and is key to delivery of the European Health 2020 policy. European policy frameworks promote a holistic approach to policy at multiple levels in society and across multiple arenas in every-day life. Methods An evidence synthesis was undertaken to describe health literacy policies in the WHO European Region: their distribution, organizational levels, antecedents, actors, activities and outcomes, along with the factors influencing their effectiveness. Evidence was obtained by a scoping review of academic literature in English, Dutch and German and of grey literature in English, Dutch, German and Italian, supported by a Region-wide expert enquiry. Emerging findings were presented to representatives from 19 Member States of the Region to check for accuracy and omissions. Results The report highlights much good health literacy policy-related activity, mostly in the health and education sectors. Fewer policy-related activities were identified in other areas, such as the lived environment, employment, the media, and digital health. Robust evaluation of policy-related activities was identified in some, but not all, policies. Conclusions Suggestions are made for policy-makers to share good health literacy policy practice, and to further develop policy aims and activities across all societal areas. An additional need is the development of robust health literacy metrics to direct resources and monitor the effectiveness of policy activities.

The heat shock protein 70s (HSP70s) are molecular chaperones implicated in many cancers and of significant interest as targets for novel cancer therapies. Several HSP70 inhibitors have been reported, but because the majority have poor physicochemical properties and for many the exact mode of action is poorly understood, more detailed mechanistic and structural insight into ligand-binding to HSP70s is urgently needed. Here we describe the first comprehensive fragment-based inhibitor exploration of an HSP70 enzyme, which yielded an amino-quinazoline fragment that was elaborated to a novel ATP binding site ligand with different physicochemical properties to known adenosine-based HSP70 inhibitors. Crystal structures of amino-quinazoline ligands bound to the different conformational states of the HSP70 nucleotide binding domain highlighted the challenges of a fragment-based approach when applied to this particular flexible enzyme class with an ATP-binding site that changes shape and size during its catalytic cycle. In these studies we showed that Ser275 is a key residue in the selective binding of ATP. Additionally, the structural data revealed a potential functional role for the ATP ribose moiety in priming the protein for the formation of the ATP-bound pre-hydrolysis complex by influencing the conformation of one of the phosphate binding loops.

The single-electron eigenstates of a cylindrical shell are determined as functions of the applied crossed electric and magnetic fields in the effective-mass approximation. The system considered consists of donor charges taken to be uniformly distributed within an inner core of infinitely long length. The core is concentrically enveloped by a semiconducting material of finite thickness; which is essentially the host material. This configuration of the donor charges sets up a spatially varying electric field nonetheless with only the radial component. In addition, a uniform magnetic field is applied parallel to the axis of symmetry of the inner core. As is well known, the axial applied magnetic field lifts the double degeneracies of the electron’s subbands characterized by the same azimuthal quantum numbers which differ only in sign. The main effect of increasing the external electric field is to elevate the various energy subbands, more or less to the same extent, to higher values. Further, evaluations of the oscillator strengths of optical transitions of the cylindrical shell are carried out within the dipole approximation. The radiation field is taken to be that of circularly polarized light incident along the axis of the core. The oscillator strengths of optical transitions are found to increase with an increase of the applied magnetic field, particularly in the regime of small magnetic fields. In contrast, the oscillator strengths of these optical interactions become suppressed as the donor charge density is increased.

Ire1 (Ern1) is an unusual transmembrane protein kinase essential for the endoplasmic reticulum (ER) unfolded protein response (UPR). Activation of Ire1 by association of its N-terminal ER luminal domains promotes autophosphorylation by its cytoplasmic kinase domain, leading to activation of the C-terminal ribonuclease domain, which splices Xbp1 mRNA generating an active Xbp1s transcriptional activator. We have determined the crystal structure of the cytoplasmic portion of dephosphorylated human Ire1 bound to ADP, revealing the phosphoryl-transfer competent dimeric face-to-face complex, which precedes and is distinct from the back-to-back RNase active conformation described for yeast Ire1. We show that the Xbp1-specific ribonuclease activity depends on autophosphorylation, and that ATP-competitive inhibitors staurosporin and sunitinib, which inhibit autophosphorylation in vitro, also inhibit Xbp1 splicing in vivo. Furthermore, we demonstrate that activated Ire1 is a competent protein kinase, able to phosphorylate a heterologous peptide substrate. These studies identify human Ire1 as a target for development of ATP-competitive inhibitors that will modulate the UPR in human cells, which has particular relevance for myeloma and other secretory malignancies.

Inhibition of histone deacetylase activity represents a promising new modality in the treatment of a number of cancers. A novel HDAC series demonstrating inhibitory activity in cell proliferation assays is described. Optimisation based on the introduction of basic amine linkers to effect good drug distribution to tumour led to the identification of a compound with oral activity in a human colon cancer xenograft study associated with increased histone H3 acetylation in tumour tissue.

We recently reported the identification of the original bisamide lead compound CCT251236 as an inhibitor of the HSF1 stress pathway with a high affinity for the putative transcription factor co-regulator, pirin (SPR KD=44nM) (Cheeseman et al., J Med Chem, 60; 180-201, 2017). Pirin is a highly conserved non-heme iron-binding regulatory protein that is a member of the functionally diverse cupin superfamily, but has no known enzymatic function or biomarkers of activity. To understand further this poorly characterized protein and to confirm that CCT251236 binds to pirin within living cells, we conceived and optimized a heterobifunctional protein degradation probe using the proteolysis targeting chimeras (PROTACs; CCT367766) comprising a pirin-binding moiety linked to the cereblon-targeting ligand thalidomide. This PROTAC molecule was designed to recruit pirin to the E3 ubiquitin ligase cereblon resulting in the ubiquitylation and degradation of pirin. Negative control probes lacking binding to pirin (CCT367857) or cereblon (CCT367936) were also designed and synthesized. We demonstrated a concentration-dependent depletion of pirin protein from as low as 0.5nM and as early as 2 hr treatment of SKOV3 human ovarian cancer cells with the PROTAC. The negative controls CCT367857 and CCT367936 exhibited no pirin depletion at equimolar concentrations. At higher concentrations of the active probe, a hook effect is observed, consistent with the formation of a ternary complex. Degradation of pirin by the PROTAC was confirmed to be proteasome-dependent by rescue of depletion following pre-incubation with the proteasome inhibitor MG132. In addition, the PROTAC could not induce pirin degradation in CRISPR/cas9 cereblon knockout SKOV3 cells, confirming dependence on cereblon. Pre-treatment with the bisamide compound CCT251236 or free thalidomide abrogated the PROTAC-induced pirin degradation, consistent with pirin and cereblon engagement. Finally, to estimate the cellular selectivity of the PROTAC to pirin in an unbiased manner, we carried out whole proteome mass spectrometry in SKOV3 cells. From 8547 quantifiable proteins identified, only pirin (2.3-fold reduction) displayed a statistically significant (Padj Citation Format: Swee Y. Sharp, Nicola E. Chessum, John J. Caldwell, Marissa V. Powers, A Elisa Pasqua, Birgit Wilding, Ian Collins, Bugra Ozer, Martin Rowlands, Mark Stubbs, Rosemary Burke, Rob L. van Montfort, Matthew D. Cheeseman, Paul A. Clarke, Paul Workman, Keith Jones. Confirmation of in-cell target engagement using the proteolysis targeting chimeras (PROTACs) against pirin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2976.

A series of resorcylic acid macrolactones, analogues of the natural product radicicol has been prepared by chemical synthesis, and evaluated as inhibitors of heat shock protein 90 (Hsp90), an emerging attractive target for novel cancer therapeutic agents. The synthesis involves acylation of an ortho-toluic acid dianion, esterification, followed by a ring-closing metathesis to form the macrocycle. Subsequent manipulation of the protected hydroxymethyl side chain allows access to a range of new analogues following de-protection of the two phenolic groups. Co-crystallization of one of the new macrolactones with the N-terminal domain of yeast Hsp90 confirms that it binds in a similar way to the natural product radicicol and to our previous synthetic analogues, but that the introduction of the additional hydroxymethyl substituent appears to result in an unexpected change in conformation of the macrocyclic ring. As a result of this conformational change, the compounds bound less favorably to Hsp90.

The molecular chaperone heat shock protein 90 (Hsp90) is required for the correct folding and stability of a number of client proteins that are important for the growth and maintenance of cancer cells. Heat shock protein 72 (Hsp72), a co-chaperone of Hsp90, is also emerging as an attractive cancer drug target. Both proteins bind and hydrolyze adenosine triphosphate (ATP), and ATPase activity is essential for their function. Inhibition of Hsp90 ATPase activity leads to the degradation of client proteins, resulting in cell growth inhibition and apoptosis. Several small-molecule inhibitors of the ATPase activity of Hsp90 have been described and are currently being evaluated clinically for the treatment of cancer. A number of methods for the measurement of ATPase activity have been previously used, but not all of these are ideally suited to screening cascades in drug discovery projects. The authors have evaluated the use of commercial reagents (Transcreener ADP) for the measurement of ATPase activity of both yeast and human Hsp90 (ATP K(m) approximately 500 microM) and human Hsp72 (ATP K(m) ~1 microM). The low ATPase activity of human Hsp90 and its stimulation by the co-chaperone Aha1 was measured with ease using reduced incubation times, generating robust data (Z' = 0.75). The potency of several small-molecule inhibitors of both Hsp90 and Hsp72 was determined using the Transcreener reagents and compared well to that determined using other assay formats.

Protein kinase B (PKB or Akt) is an important component of intracellular signaling pathways regulating growth and survival. Signaling through PKB is frequently deregulated in cancer, and inhibitors of PKB therefore have potential as antitumor agents. The optimization of lipophilic substitution within a series of 4-benzyl-1-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)piperidin-4-amines provided ATP-competitive, nanomolar inhibitors with up to 150-fold selectivity for inhibition of PKB over the closely related kinase PKA. Although active in cellular assays, compounds containing 4-amino-4-benzylpiperidines underwent metabolism in vivo, leading to rapid clearance and low oral bioavailability. Variation of the linker group between the piperidine and the lipophilic substituent identified 4-amino-1-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)piperidine-4-carboxamides as potent and orally bioavailable inhibitors of PKB. Representative compounds modulated biomarkers of signaling through PKB in vivo and strongly inhibited the growth of human tumor xenografts in nude mice at well-tolerated doses.

A series of benzo-macrolactones has been prepared by chemical synthesis, and evaluated as inhibitors of heat shock protein 90 (Hsp90), an emerging attractive target for novel cancer therapeutic agents. A new synthesis of these resorcylic acid macrolactone analogues of the natural product radicicol is described in which the key steps are the acylation and ring opening of a homophthalic anhydride to give an isocoumarin, followed by a ring-closing metathesis to form the macrocycle. The methodology has been extended to a novel series of macrolactones incorporating a 1,2,3-triazole ring.

High-throughput screening led to the identification of isothiazolones 1 and 2 as inhibitors of histone acetyltransferase (HAT) with IC50s of 3 microM and 5 microM, respectively. Analogues of these hit compounds with variations of the N-phenyl group, and with variety of substituents at C-4, C-5 of the thiazolone ring, were prepared and assayed for inhibition of the HAT enzyme PCAF. Potency is modestly favoured when the N-aryl group is electron deficient (4-pyridyl derivative 10 has IC(50)=1.5 microM); alkyl substitution at C-4 has little effect, whilst similar substitution at C-5 causes a significant drop in potency. The ring-fused compound 38 has activity (IC(50)=6.1 microM) to encourage further exploration of this bicyclic structure. The foregoing SAR is consistent with an inhibitory mechanism involving cleavage of the S-N bond of the isothiazolone ring by a catalytically important thiol residue.

The objective of the study was to determine risk factors for late skin flap failure following cochlear implantation. The study design was a retrospective case series. Data were collated from 371 implanted patients over a ten-year period. Of these patients, 1.3 per cent (n = 5) developed late skin flap failure. It is concluded that skin flap failure is a significant, though relatively uncommon, complication of cochlear implant surgery. What causes flap failure and why it should occur in such a variable fashion are still largely unknown, though infection undoubtedly plays an important role. The aetiological factors associated with flap failure and possible prevention strategies are discussed. Copyright © 2008 John Wiley & Sons, Ltd.

Objective:To establish the prevalence of new vestibular and otological symptoms in a group of patients who had sustained a low grade (Quebec grades one or two) whiplash injury.Methods:A retrospective review of the case records of 109 patients undergoing assessment by a single practitioner for the purposes of compiling a medicolegal report on their whiplash injury.Results:Four patients complained of short-lived, non-specific dizziness symptoms in the acute phase following their original injury. There were no reports of vertigo, tinnitus or hearing loss after a mean period of 149 days following the whiplash injury.Conclusions:No patients reported otological or persistent vestibular symptoms in the acute phase following their whiplash injury. This suggests that caution should be exercised when attributing these symptoms to such an injury. Before whiplash injuries are admitted as an aetiological factor in the development of such symptoms, other causes should be excluded.

We describe the biological properties of NVP-AUY922, a novel resorcinylic isoxazole amide heat shock protein 90 (HSP90) inhibitor. NVP-AUY922 potently inhibits HSP90 (Kd = 1.7 nmol/L) and proliferation of human tumor cells with GI50 values of approximately 2 to 40 nmol/L, inducing G1-G2 arrest and apoptosis. Activity is independent of NQO1/DT-diaphorase, maintained in drug-resistant cells and under hypoxic conditions. The molecular signature of HSP90 inhibition, comprising induced HSP72 and depleted client proteins, was readily demonstrable. NVP-AUY922 was glucuronidated less than previously described isoxazoles, yielding higher drug levels in human cancer cells and xenografts. Daily dosing of NVP-AUY922 (50 mg/kg i.p. or i.v.) to athymic mice generated peak tumor levels at least 100-fold above cellular GI50. This produced statistically significant growth inhibition and/or regressions in human tumor xenografts with diverse oncogenic profiles: BT474 breast tumor treated/control, 21%; A2780 ovarian, 11%; U87MG glioblastoma, 7%; PC3 prostate, 37%; and WM266.4 melanoma, 31%. Therapeutic effects were concordant with changes in pharmacodynamic markers, including induction of HSP72 and depletion of ERBB2, CRAF, cyclin-dependent kinase 4, phospho-AKT/total AKT, and hypoxia-inducible factor-1α, determined by Western blot, electrochemiluminescent immunoassay, or immunohistochemistry. NVP-AUY922 also significantly inhibited tumor cell chemotaxis/invasion in vitro, WM266.4 melanoma lung metastases, and lymphatic metastases from orthotopically implanted PC3LN3 prostate carcinoma. NVP-AUY922 inhibited proliferation, chemomigration, and tubular differentiation of human endothelial cells and antiangiogenic activity was reflected in reduced microvessel density in tumor xenografts. Collectively, the data show that NVP-AUY922 is a potent, novel inhibitor of HSP90, acting via several processes (cytostasis, apoptosis, invasion, and angiogenesis) to inhibit tumor growth and metastasis. NVP-AUY922 has entered phase I clinical trials. [Cancer Res 2008;68(8):2850–60]

Fragment-based screening identified 7-azaindole as a protein kinase B inhibitor scaffold. Fragment elaboration using iterative crystallography of inhibitor-PKA-PKB chimera complexes efficiently guided improvements in the potency and selectivity of the compounds, resulting in the identification of nanomolar 6-(piperidin-1-yl)purine, 4-(piperidin-1-yl)-7-azaindole, and 4-(piperidin-1-yl)pyrrolo[2,3- d]pyrimidine inhibitors of PKBbeta with antiproliferative activity and showing pathway inhibition in cells. A divergence in the binding mode was seen between 4-aminomethylpiperidine and 4-aminopiperidine containing molecules. Selectivity for PKB vs PKA was observed with 4-aminopiperidine derivatives, and the most PKB-selective inhibitor (30-fold) showed significantly different bound conformations between PKA and PKA-PKB chimera.

The PPM1D gene is aberrantly amplified in a range of common cancers and encodes a protein phosphatase that is a potential therapeutic target. However, the issue of whether inhibition of PPM1D in human tumour cells that overexpress this protein compromises their viability has not yet been fully addressed. We show here, using an RNA interference (RNAi) approach, that inhibition of PPM1D can indeed reduce the viability of human tumour cells and that this effect is selective; tumour cell lines that overexpress PPM1D are sensitive to PPM1D inhibition whereas cell lines with normal levels are not. Loss of viability associated with PPM1D RNAi in human tumour cells occurs via the activation of the kinase P38. To identify chemical inhibitors of PPM1D, a high-throughput screening of a library of small molecules was performed. This strategy successfully identified a compound that selectively reduces viability of human tumour cell lines that overexpress PPM1D. As expected of a specific inhibitor, the toxicity to PPM1D overexpressing cell lines after inhibitor treatment is P38 dependent. These results further validate PPM1D as a therapeutic target and identify a proof-of-principle small molecule inhibitor.

We have studied single-domain particles of nonellipsoidal shape and of uniform magnetization and have found that the demagnetizing energy is independent of the direction of magnetization in bodies with certain symmetries. Our study used several symmetries containing rotation or rotoinversion in the calculation of demagnetizing energies in various directions of axis

In a recent paper (Goode and Rowlands J. Magn. Magn. Mater. 295 (2005) 197–218), the micromagnetic equations which govern the magnetization distribution have been studied for rectangular nano-sized magnets where the magnetization is nearly uniform. Analytical solutions to these equations have been obtained in the form of Fourier series in which only the first few terms in the series are necessary to give results accurate to a few percent. In this paper, the above method is extended to include the effects of interaction between two or more rectangular nanomagnets. The near-uniform nature of the magnetization distributions is shown to change depending on the distance the nanomagnets are apart from each other. To estimate at what distance between the nanomagnets this interaction becomes important and therefore must be included in the analysis, the demagnetizing and interaction energies are compared for an array of uniformly magnetized rectangular nanomagnets.

Many processes in astrophysical plasmas are directly related to magnetic connection in the presence of turbulent fluctuations. Even statistically homogeneous turbulence can contain closed topological structures that inhibit otherwise random transport of field line trajectories, thus temporarily trapping certain trajectories. When a coherent random field perturbation is added, the trapped field lines can escape diffusively but at a suppressed rate that is much lower than what would be estimated based on the perturbation field alone. Here we demonstrate both trapping and escape, and show, using a novel quasi-linear theory, how to compute the suppressed diffusion that affects the escape from the trapping structure. The effect is relevant to understanding filamentary magnetic connection in interplanetary space and the observed dropouts in moderately energetic particles from impulsive solar flares. Expressed here in terms of a magnetic field line random walk, this phenomenon also has analogies in a broad range of dynamical systems that evolve as an incompressible flow in phase space with a coherent perturbation.

Histone acetylation plays an important role in regulating the chromatin structure and is tightly regulated by two classes of enzyme, histone acetyltransferases (HAT) and histone deacetylases (HDAC). Deregulated HAT and HDAC activity plays a role in the development of a range of cancers. Consequently, inhibitors of these enzymes have potential as anticancer agents. Several HDAC inhibitors have been described; however, few inhibitors of HATs have been disclosed. Following a FlashPlate high-throughput screen, we identified a series of isothiazolone-based HAT inhibitors. Thirty-five N-substituted analogues inhibited both p300/cyclic AMP–responsive element binding protein–binding protein–associated factor (PCAF) and p300 (1 to >50 μmol/L, respectively) and the growth of a panel of human tumor cell lines (50% growth inhibition, 0.8 to >50 μmol/L). CCT077791 and CCT077792 decreased cellular acetylation in a time-dependent manner (2–48 hours of exposure) and a concentration-dependent manner (one to five times, 72 hours, 50% growth inhibition) in HCT116 and HT29 human colon tumor cell lines. CCT077791 reduced total acetylation of histones H3 and H4, levels of specific acetylated lysine marks, and acetylation of α-tubulin. Four and 24 hours of exposure to the compounds produced the same extent of growth inhibition as 72 hours of continuous exposure, suggesting that growth arrest was an early event. Chemical reactivity of these compounds, as measured by covalent protein binding and loss of HAT inhibition in the presence of DTT, indicated that reaction with thiol groups might be important in their mechanism of action. As one of the first series of small-molecule inhibitors of HAT activity, further analogue synthesis is being pursued to examine the potential scope for reducing chemical reactivity while maintaining HAT inhibition.

Theguidelines recommended that pa-tients with mild uncomplicatedhypertension (blood pressure (BP)140–159/90–99mmHg) be treatedif at high CHD risk (10-year CHDrisk X15% equivalent to a 10-yearCVD risk X20%). However, inethnic minorities in the UK, theestimated CHD risk is not an accu-rate representation of their totalrisk of cardiovascular disease.

Shock waves have been proposed in the literature as a mechanism for retinal damage induced by ultra-short laser pulses. For a spherical absorber, we derive a set of linear equations describing the propagation of pressure waves. We show that the formation of shock fronts is due to the form of the absorber rather than the inclusion of nonlinear terms in the equations. The analytical technique used avoids the need for a Laplace transform approach and is easily applied to other absorber profiles. Our analysis suggests that the 'soft' nature of the membrane surrounding retinal melanosomes precludes shock waves as a mechanism for the retinal damage induced by ultra-short pulse lasers. The quantitative estimates of the pressure gradients induced by laser absorption which are made possible by this work, together with detailed meso-scale or molecular modelling, will allow alternative damage mechanisms to be identified.

Thin epoxy resin adhesive samples were ultrasonically measured during cure using normal incidence radially polarized shear wave electromagnetic acoustic transducers (EMATs). The EMATs used generated predominantly SH shear waves but they also generated/detected compression waves allowing the simultaneous measurement of shear and compression wave propagation through a curing epoxy in a non-contact regime. The source of the compression wave generation has been determined to be the in-plane shear Lorentz force. The adhesive thickness examined in the experiments was approximately 1 mm, which was optimal for experimental measurement using our apparatus: it temporally separated the ultrasonic waves of interest from others present in the pulse whilst remaining thin enough to be representative of a realistic adhesive layer. The rapid cure and standard or 'longer' cure epoxy adhesives described in this paper were supplied in a two-part cartridge form. The experiments show that there is a fundamental difference between the way that the elastic moduli develop in the rapid cure and the longer cure time epoxies. The rapid cure epoxy initially developed a shear elastic modulus at a fast rate, which suddenly decreased at approximately the same time that the temperature of the adhesive reached its maximum value during the exothermic reaction. The reflection measurements show that there was significant coupling of the shear wave into the adhesive even in its initial liquid-like state. The ultrasonic shear and compression wave velocities of the epoxy were calculated from the very outset of the cross-linking reaction using the reflection technique. A transmitted compression wave was visible from the outset of cure, and once a transmitted shear wave was detectable it was possible to measure attenuation for both; however, these data are not presented here as they are not key to the paper and they can be found in our previous publications that are referenced in this one.

Analytic expressions for the demagnetizing energies are obtained in the form of partial series, for long elliptic cylinders and for squat ones where the ellipticity of the cross-section is unrestrained. This leaves just a small range where the demagnetizing energies are not well defined. It is found that by replacing the elliptic cylinders with rectangular blocks, a good approximation to the demagnetizing energy may be made in this small range.

We describe a new model for laser-induced retinal damage. Our treatment is prompted by the failure of the traditional approach to accurately describe the image size dependence of laser-induced retinal injuries and by a recently reported study which demonstrated that laser injuries to the retina might not appear for up to 48 h post exposure. We propose that at threshold a short-duration, laser-induced, temperature rise melts the membrane of the melanosomes found in the pigmented retinal epithelial cells. This results in the generation of free radicals which initiate a slow chain reaction. If more than a critical number of radicals are generated then cell death may occur at a time much later than the return of the retina to body temperature. We show that the equations consequent upon this mechanism result in a good fit to the recent image size data although more detailed experimental data for rate constants of elementary reactions is still required. This paper contributes to the current understanding of damage mechanisms in the retina and may facilitate the development of new treatments to mitigate laser injuries to the eye. The work will also help minimize the need for further animal experimentation to set laser eye safety standards.

The Berk–Breizman augmentation of the Vlasov–Maxwell system is widely used to model self-consistent resonant excitation and damping of wave fields by evolving energetic particle populations in magnetic fusion plasmas. The key model parameters are the particle annihilation rate νa, which drives bump-on-tail structure, and the linear wave damping rate γd. A code, based on the piecewise parabolic method, is used to integrate the fully nonlinear Berk–Breizman system of equations across the whole (νa,γd) parameter space. The results of this code show that the system’s behavior can be classified into one of four types, each of which occurs in a well-defined region of parameter space: chaotic, periodic, steady state, and damped. The corresponding evolution in (x,v) phase space is also examined.

We discuss the factors affecting estimates of the true depth of sharp features such as delta layers from their responses in SIMS depth profiles. We show that the apparent position of the centroid (or peak) is strongly dependent on the interval between deltas, and examine response coalscence as a function of beam energy. The peak-to-valley ratio in the coalesced response for two adjacent deltas must be >50 before parameters such as energy-dependent profile shifts can be established with sufficient accuracy. Similarly, the sampling density must yield >10–15 data points over the top three resolved orders of magnitude. Finally we show that a delta layer structure characterized by TEM provides very accurate depth calibration.

An on-line low frequency microwave moisture measurement technique has been developed that is suited to both conventional coal applications and those that were previously too difficult. The wider range of application has been enabled through increased performance in dynamic range and accuracy. The performance enhancements have been achieved by utilizing recent advances in microwave technology in the 0.9-1.8 GHz frequency band intended for mobile communications applications. A commercial prototype low frequency moisture analyzer has been under development for the past two years. The main criteria in the design of the analyzer were: reduced hardware cost, increased accuracy and dynamic range of measurement, and an interactive user interface to simplify analyzer calibration and use. The first two commercial prototype analyzers were installed on the ship-loading conveyors at Dalrymple Bay Coal Terminal (Queensland, Australia) in early 2001 and monitor approximately 40 MT of shipped coal per year on conveyors c...

There is presently enormous interest in the function and regulatory roles of histone acetyltransferase enzymes. Along with deacetylases it is now evident that these enzymes play a key role in many cellular processes including chromatin remodeling and gene transcription. As such, effective small molecule enzyme inhibitors would be useful tools for molecular pharmacology and may also be suitable for further development into agents for the treatment of diseases such as cancer. A high-throughput assay based on the use of scintillating microplates (FlashPlates) suitable for screening libraries of compounds for inhibitors of acetylase activity is described here. Confirmation of activity of selected compounds is achieved with a conventional filter assay, the details of which are also described. In addition, an assay suitable for confirming that cellular protein acetylation has been altered by inhibition of acetylases or deacetylases is also presented. On the same plate, cells are grown, exposed to compound, fixed, and permeabilized, and protein acetylation is determined using standard ELISA methodology and a europium-labeled second antibody. This latter method provides a medium-throughput alternative to the use of immunoblotting for mechanistic studies.

Heat shock factor 1 (HSF1) was originally identified as a master regulator of the classical ‘cytoprotective’ heat shock response. However, a large body of evidence has now verified the importance of HSF1 to tumorigenesis and cancer progression. HSF1 is activated by various elements of the cancer state, reprogramming the transcriptome in a way that is overlapping with, but distinct from, the canonical heat-shock response. Also, there is a strong correlation between the expression of activated HSF1 in tumors and adverse clinical outcomes. This evidence indicates that the inhibition of HSF1-mediated transcription could be a viable strategy in cancer treatment. Inhibiting the HSF1 stress pathway represents an attempt at targeting non-oncogene addiction and proteotoxic stress, which has been proposed to be advantageous. However, HSF1 is a ligandless transcription factor and is unlikely to be amenable to standard drug discovery strategies and direct inhibition with small molecules. Therefore, we proposed that inhibitors of HSF1-mediated transcription, which antagonize the HSF1 pathway but without necessarily binding directly to HSF1, could be discovered and developed via a cell-based phenotypic screen. We carried out a high throughput Arrayscan assay of 200,000 compounds to measure the inhibition of HSF1-mediated HSP72 expression stimulated by pre-treatment with an HSP90 inhibitor. We identified a singleton hit with a bisamide core, CCT245232. This compound showed potent growth inhibition in a range of human cancer cell lines but had poor physicochemical properties leading to an unacceptable pharmacokinetic profile. Improvement of the physicochemical properties of CCT245232 whilst maintaining potency versus our cell-based assays led to the orally bioavailable tool compound CCT251236. This compound shows potent growth inhibition (GI50 values in low nanomolar range) of human ovarian cancer cell lines in vitro and good efficacy against human ovarian cancer xenografts in nude mice in vivo. We applied chemo-proteomic strategies to identify the molecular target using a probe based on CCT251236 and discovered pirin as a high affinity molecular target. Binding of CCT251236 to recombinant pirin was confirmed in biophysical assays. CCT251236 recapitulates the reported anti-migratory phenotype for a pirin ligand although binding to pirin alone does not explain the cellular phenotype observed with our chemical tool. We are currently using CCT251236 as a chemical probe while further optimizing its properties to identify a clinical candidate. Citation Format: Matthew D. Cheeseman, Nicola E. Chessum, Carl S. Rye, Elisa A. Pasqua, Michael J. Tucker, Birgit Wilding, Lindsay E. Evans, Susan Lepri, Meirion Richards, Swee Y. Sharp, Salyha Ali, Martin Rowlands, Lisa O'Fee, Asadh Miah, Angela Hayes, Alan T. Henley, Marissa Powers, Robert te Poele, Emmanuel De Billy, Loredana Pellegrino, Florence Raynaud, Rosemary Burke, Robert L. van Montfort, Suzanne A. Eccles, Keith Jones, Paul Workman. Discovery of chemical probe CCT251236: An orally bioavailable efficacious pirin ligand from an HSF1 phenotypic screen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-304. doi:10.1158/1538-7445.AM2017-LB-304

The role of histone acetyltransferases (HATs) in the regulation of crucial cellular functions, e.g., gene transcription, differentiation, and proliferation, has recently been documented and there is increasing evidence that aberrant expression of these enzymes may have a role to play in the development of the malignant phenotype. The availability of potent and selective small molecule inhibitors of HATs would provide useful proof of principle probes for further validation of these enzymes as drug discovery targets and may also provide lead molecules for clinical drug development. We have developed a microplate assay for HAT activity suitable for high-throughput screening. In the assay, following incubation of histone H3, [3H]acetylCoA, and enzyme (recombinant p300/CBP-associated factor expressed as a glutathione S-transferase fusion protein), radiolabeled histone was captured onto the walls of a scintillating microplate (FlashPlate) generating a scintillation signal. The assay was reproducible, amenable to automation, and generated a wide signal to noise ratio. Although antiacetylated histone antibodies were initially used to capture the radiolabeled product, it was subsequently shown that a signal was effectively produced by histone passively binding to the walls of the FlashPlate. This resulted in a simple "mix and measure" assay that is currently being used for the identification of HAT inhibitors.

Extramedullary hematopoiesis is rare outside the setting of significant primary hematologic disease. We describe this phenomenon in an exuberant pyogenic granuloma in an otherwise healthy man. We postulate that this vascular lesion provided a suitable milieu for homing and proliferation of stem cells.

Pentafluoronitrobenzene was converted via two successive phase-transfer catalysed SNAr reactions with (E,E)-farnesol or geraniol followed by hydroxide ion into the 2,3,6-trifluoro-5-hydroxy-4-nitrophenyl farnesyl ether 3a and the geranyl ether 3b. Analogues containing a cyano (3c) or carbamoyl (3d) group in place of nitro or an epoxygeranyl (3e) group as the prenyl (3-methylbut-2-enyl) containing residue were similarly prepared. Those containing a sulfonic acid (35a, 35b) or a methyl sulfone (41) group were made by modifications of this approach involving the use of protecting groups. The synthesis of carboxy analogues (27a, 27b) involved the alkylation of a protected fluorinated ortho-hydroxybenzoic acid derivative (25) with (E,E)-farnesyl or geranyl bromide. The non-fluorinated compound 18 was analogously prepared via compound 17a. Mitsunobu reactions were used in the synthesis of 15, a dihydroxylated analogue of 3b, and of 8, the non-fluorinated analogue of 3a. The nitro compounds 3a and 3b were moderate inhibitors of both farnesyl transferase and geranylgeranyl transferase I, the geranyl carboxy derivative 27b of the latter enzyme and the farnesyl sulfonic acid derivative 35a of squalene synthase.

A vegetation survey was conducted in the Pumphouse Wash canyon system, south of Flagstaff, Arizona. Plant species distribution, abundance, and diversity were quantified within and among canyons in this sensitive ephemeral riparian area. Abiotic variables were examined to see if they could predict vegetation diversity. Results of stand ordination and cluster analysis suggested that variation in vegetation distribution and composition was best explained by a complex temperature/moisture - substrate gradient. Understory diversity in general was related to changes in slope and sand/gravel substrate. Each tributary canyon supported unique plant species and the riparian vegetation in one tributary canyon was significantly less diverse than in each of the other canyons. The two canyons with the lowest understory diversity contained rare plant species not found in the other, more diverse canyons. Thus, overall diversity was demonstrated to be a poor predictor of the presence of rare species. Similarly, abiotic variation was useful at predicting diversity levels but was not useful at predicting species occurrence or ecological quality. In summary, attributes frequently considered of use for predicting conservation value of one type (e.g., diversity) were not good at predicting other conservation values (e.g., rarity).

In this note we calculate the effective drift velocities and the effective diffusivities of swimming microorganisms in an external flow field. It is shown that if the ambient velocity field is incompressible then the effects of reorientation of the cells can under certain circumstances enhance the effective drift velocity along the preferred direction.

Background Granulocytic sarcoma (GS) is the rare extramedullary manifestation of acute myeloid leukemia that may precede or be concurrent with leukemic infiltration of bone marrow or herald blastic transformation of a chronic myeloproliferative disorder. It has been found in most body sites and shows no age or sex predilection, necessitating its inclusion in the differential diagnosis of undifferentiated neoplasms. Case A 36-year-old female presented with a three-year history of abdominal pain, jaundice and fluctuating abdominal girth. Cytology of the ascitic fluid revealed myeloid cells of eosinophilic lineage at all stages of differentiation, with many undifferentiated cells. Immunohistochemical studies on a cell block confirmed the diagnosis of granulocytic sarcoma, which excluded the differential diagnoses of Hodgkin's disease, non-Hodgkin's lymphoma and Langerhans histiocytosis. Conclusion Granulocytic sarcoma may present as a serous effusion and can be diagnosed on a cytologic specimen.

Dermatofibrosarcoma protuberans (DFSP) is a rare soft tissue tumour of the dermis. Diagnosis may be very difficult from both a clinical and histopathological standpoint. DFSP has a peak incidence in patients between age 10 and 50 years old, occurs with relatively equal frequency in males and females and has a predilection to occur on the trunk or proximal limbs. The tumour has a very low metastatic potential but can be very locally aggressive, requiring wide surgical resection. The possible variants of DFSP may obscure diagnosis especially in the case of fibrohistiocytic lesions such as dermatofibroma, fibromatosis and malignant fibrous histiocytoma. Immunohistological testing, while not completely specific, shows promise in improving diagnostic accuracy. Wide local excision continues to be the mainstay of treatment, although Mohs’ micrographic surgery may ultimately provide superior cure rates.

The surface magnetic charge distributions with edge singularities are studied for a half-infinite circular cylinder with uniform permeability. The cylinder is placed in an axially uniform magnetic field. The subject of this study is the charge densities around the edges on both side and end surfaces. The charge densities over a certain distance from the edge on the side surface are regarded as constant. It is shown that an integral equation can be found for the charge density around the edge on the side surface. The unknown quantity in the integral equation is expressed as a product of a bounded function and an edge-singular power function depending on the relative permeability. The charge density on the end surface is expressed as a function of the charge densities on the side surface. Numerical calculations are carried out for various values of the relative permeability and are illustrated to clarify the surface magnetic charge densities. The charge densities around the edge are proportional to a certain inverse power of a distance from the edge. It is clarified for the first time that the edge singularity power factor increases with the relative permeability /spl mu/ and is equal to the same on the right-angled wedge of the same /spl mu/.

A Fokker - Planck description of chaotic dynamical systems, with phase space dependent transport coefficients is proposed. Ways of analytically obtaining these local transport coefficients are proposed. A comparison with numerical results for three model systems is made.

A simple method for the determination of the position of singularities in the complex time domain for dynamical systems which are described by ordinary differential equations is presented. The method is designed for integrable separable systems whose solutions are not expressible in closed form. A direct consequence of this method is that it ‘closes’ the phase space. Simple physical meaning is given to the singularity position.

Antiestrogens are widely used in the treatment of hormone dependent breast cancer. Their principle mechanism of action is believed to be the displacement of the growth promoting hormone estrogen from its protein receptor. Many antiestrogens also exhibit hormone independent effects, such as antagonism of the calcium binding protein calmodulin, which may contribute to their therapeutic potential. Calmodulin is essential to many cellular processes including the functioning of the estrogen receptor. The- possibility that a combined antiestrogen - calmodulin antagonist would be useful for cancer therapy has led to the development of antiestrogens which are potent calmodulin antagonists. This review describes the structure - activity relationships for calmodulin antagonists, the rational design of such compounds and their biological properties. The synthetic methodology for some of these antiestrogens will also be discussed.

Various 3- and 4-pyridylalkyl 1-adamantanecarboxylates have been synthesized and tested for inhibitory activity toward the 17 alpha-hydroxylase and C17,20-lyase activities of human testicular cytochrome P450(17 alpha). The 4-pyridylalkyl esters were much more inhibitory than their 3-pyridylalkyl counterparts. The most potent was (S)-1-(4-pyridyl)ethyl 1-adamantanecarboxylate (3b; IC50 for lyase, 1.8 nM), whereas the (R)-enantiomer 3a was much less inhibitory (IC50 74 nM). Nearly as potent as 3b was the dimethylated counterpart, the 2-(4-pyridylpropan-2-yl) ester 5 (IC50 2.7 nM), which was also more resistant to degradation by esterases. In contrast to their 4-pyridyl analogs, the enantiomers of the 1-(3-pyridyl)ethyl ester were similarly inhibitory (IC50 for lyase; (R)-isomer 8a 150 nM, (S)-isomer 8b 230 nM). Amides corresponding to the 4-pyridylmethyl ester 1 and the (S)-1-(4-pyridyl)ethyl ester 3b, respectively 11 and 15b, were much less inhibitory than their ester counterparts. On the basis of a combination of inhibitory potency and resistance to esterases, the ester 5 was the best candidate for further development as a potential nonsteroidal inhibitor of cytochrome P450(17 alpha) for the treatment of prostate cancer.

A series of homologs of idoxifene [1a, (E)-1-[4-(N-pyrrolidinoethoxy)phenyl]-1-(4-iodophenyl)-2-phenyl-1-butene ] and selected homologs of 4-iodotamoxifen [2a,(E)-1-[4-(N-dimethylamino)-ethoxy]phenyl]-1-(4-iodophenyl)-2-phenyl -1-butene] with the side chain (CH(2))(n) varying in length from n=3 (1b,2b) to n=10(1i,2i) have been synthesized and tested for antagonism of of the calmodulin-dependent activity of cAMP phosphodiesterase and for binding affinity to rat uterine estrogen receptor. Compared with 1a (IC(50) =1.5 microM), the homologs showed a progressive increase in calmodulin antagonism with a maximum inhibition at n=7-9 (1f-h)(IC(50)=0.2 microM), declining at n=10 (1i) to IC(50) =1.6 microM. In the pyrrolidino series, estrogen receptor binding affinity peaked at n=3 (1b, RBA= 23; estradiol = 100), declining by n=10 (1i) to RBA = 0.4, but the homolog n=8 (1g, RBA = 3.5) was still comparable to tamoxifen (RBA = 3.9). A similar pattern of activity was seen for the dimethylamino counterparts. These compounds represent a new class of antiestrogens with potent calmodulin antagonism.