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International audience; We report the experimental generation of a broadband and flat mid-infrared supercontinuum in a silicongermanium-on-silicon two-stage waveguide. Our particular design combines a short and narrow waveguide section for efficient supercontinuum generation, and an inverse tapered section that promotes the generation of two spectrally shifted dispersive waves along the propagation direction, leading to an overall broader and flatter supercontinuum. The experimentally generated supercontinuum extended from 2.4 to 5.5 µm, only limited by the long wavelength detection limit of our spectrum analyzer. Numerical simulations predict that the supercontinuum actually extends to 7.8 µm. We exploit the enhanced flatness of our supercontinuum for a proof-of-principle demonstration of free-space multi-species gas spectroscopy of water vapor and carbon dioxide.

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Intrinsic and acquired resistance to HER-targeting drugs occurs in a significant proportion of HER2-overexpressing breast cancers. Thus, there remains a need to identify predictive biomarkers that could improve patient selection and circumvent these types of drug resistance. Here, we report the identification of neuromedin U (NmU) as an extracellular biomarker in cells resistant to HER-targeted drugs. NmU overexpression occurred in cells with acquired or innate resistance to lapatinib, trastuzumab, neratinib, and afatinib, all of which displayed a similar trend upon short-term exposure, suggesting NmU induction may be an early response. An analysis of 3,489 cases of breast cancer showed NmU to be associated with poor patient outcome, particularly those with HER2-overexpressing tumors independent of established prognostic indicators. Ectopic overexpression of NmU in drug-sensitive cells conferred resistance to all HER-targeting drugs, whereas RNAi-mediated attenuation sensitized cells exhibiting acquired or innate drug resistance. Mechanistic investigations suggested that NmU acted through HSP27 as partner protein to stabilize HER2 protein levels. We also obtained evidence of functional NmU receptors on HER2-overexpressing cells, with the addition of exogenous NmU eliciting an elevation in HER2 and EGFR expression along with drug resistance. Finally, we found that NmU seemed to function in cell motility, invasion, and anoikis resistance. In vivo studies revealed that NmU attenuation impaired tumor growth and metastasis. Taken together, our results defined NmU as a candidate drug response biomarker for HER2-overexpressing cancers and as a candidate therapeutic target to limit metastatic progression and improve the efficacy of HER-targeted drugs. Cancer Res; 74(14); 3821–33. ©2014 AACR.

Aims: The management of congestion is one of the key treatment targets in heart failure. Assessing congestion is, however, difficult. The purpose of this study was to investigate the safety and dynamic response of a novel, passive, inferior vena cava (IVC) sensor in a chronic ovine model.Methods and results: A total of 20 sheep divided into three groups were studied in acute and chronic in vivo settings. Group I and Group II included 14 sheep in total with 12 sheep receiving the sensor and two sheep receiving a control device (IVC filter). Group III included an additional six animals for studying responses to volume challenges via infusion of blood and saline solutions. Deployment was 100% successful with all devices implanted; performing as expected with no device-related complications and signals were received at all observations. At similar volume states no significant differences in IVC area normalized to absolute area range were measured (55 ± 17% on day 0 and 62 ± 12% on day 120, p = 0.51). Chronically, the sensors were completely integrated with a thin, reendothelialized neointima with no loss of sensitivity to infused volume. Normalized IVC area changed significantly from 25 ± 17% to 43 ± 11% (p = 0.007) with 300 ml infused. In contrast, right atrial pressure required 1200 ml of infused volume prior to a statistically significant change from 3.1 ± 2.6 mmHg to 7.5 ± 2.0 mmHg (p = 0.02).Conclusion: In conclusion, IVC area can be measured remotely in real-time using a safe, accurate, wireless, and chronic implantable sensor promising to detect congestion with higher sensitivity than filling pressures.

Refractory status epilepticus is a clinical emergency associated with high mortality and morbidity. Increasing evidence suggests neuroinflammation contributes to the development of drug-refractoriness during status epilepticus. Here, we have determined the contribution of the ATP-gated P2X7 receptor, previously linked to inflammation and increased hyperexcitability, to drug-refractory status epilepticus and its therapeutic potential.Status epilepticus was induced via a unilateral microinjection of kainic acid into the amygdala in adult mice. Severity of status epilepticus was compared in animals with overexpressing or knock-out of the P2X7 receptor, after inflammatory priming by pre-injection of bacterial lipopolysaccharide (LPS) and in mice treated with P2X7 receptor-targeting and anti-inflammatory drugs.Mice overexpressing P2X7 receptors were unresponsive to several anticonvulsants (lorazepam, midazolam, phenytoin and carbamazepine) during status epilepticus. P2X7 receptor expression increased in microglia during status epilepticus, at times when responses to anticonvulsants were reduced. Overexpression of P2X7 receptors induced a pro-inflammatory phenotype in microglia during status epilepticus and the anti-inflammatory drug minocycline restored normal responses to anticonvulsants in mice overexpressing P2X7 receptors. Pretreatment of wild-type mice with LPS increased P2X7 receptor levels in the brain and reduced responsiveness to anticonvulsants during status epilepticus, which was overcome by either genetic deletion of P2X7 receptors or treatment with the P2X7 receptor antagonists, AFC-5128 or ITH15004.Our results demonstrate that P2X7 receptor-induced pro-inflammatory effects contribute to resistance to pharmacotherapy during status epilepticus. Therapies targeting P2X7 receptors could be novel adjunctive treatments for drug-refractory status epilepticus.

Promoting myelination capacity of endogenous oligodendrocyte precursor cells (OPCs) is a promising therapeutic approach for central nervous system demyelinating disorders such as Multiple Sclerosis (MS). To aid in the discovery of myelination promoting compounds, we generated an advanced, genome engineered, human pluripotent stem cell (hPSC) line that consist of three reporters (identification-and-purification tag, GFP, and secreted NanoLuc) driven by the endogenous PDGFRα, PLP1 and MBP genes, respectively. Based upon this line, we established a high-throughput drug screening platform and performed a small molecule screen with 2500 bioactive molecules. In addition to a number of previously known pathways, our screening effort identified new pathways whose inhibition enhance oligodendrocyte maturation and myelination. Although further genetic and molecular validation is required, the identified inhibitors could potentially be repurposed to develop remyelination therapy for MS and other demyelinating disorders.

The required fidelity of synthetic materials in surgical simulators to teach tissue handling and repair requirements should be as accurate as possible. There is a poor understanding of the relationship between choice of muscle surrogates and training outcome for trainee surgeons. To address this, the mechanical characteristics of several candidate synthetic muscle surrogates were measured, and their subjective biofidelity was qualitatively assessed by surgeons.Silicone was selected after assessing several material options and 16 silicone-based surrogates were evaluated. Three of the closest samples to muscle (Samples 1.1, 1.2, 1.3) and one with inserted longitudinal fibres (1.2F) were mechanically tested in the following: compression and tension, needle puncture force and suture pull-out in comparison with real muscle. The four samples were evaluated by 17 Plastic and Orthopaedic surgeons to determine their views of the fidelity with regard to the handling properties, needle insertion and ease of suture pull-out.The mechanical testing showed the surrogates exhibited varying characteristics that matched some of the properties of muscle, though none recreated all the mechanical characteristics of native muscle. Good biofidelity was generally achieved for compression stiffness and needle puncture force, but it was evident that tensile stiff was too low for all samples. The pull-out forces were variable and too low, except for the sample with longitudinal fibres. In the qualitative assessment, the overall median scores for the four surrogate samples were all between 30 and 32 (possible range 9-45), indicating limited differentiation of the samples tested by the surgeons.The surrogate materials showed a range of mechanical properties bracketing those of real muscle, thus presenting a suitable combination of candidates for use in simulators to attain the requirements as set out in the learning outcomes of muscle repair. However, despite significant mechanical differences between the samples, all surgeons found the samples to be similar to each other.

Hi-5 is an ERC-funded project hosted at KU Leuven and a proposed visitor instrument for the VLTI. Its primary goal is to image the snow line region around young planetary systems using nulling interferometry in the L’ band, between 3.5 and 4.1 μm, where the contrast between exoplanets and their host stars is very advantageous. The breakthrough is the use of a photonic chip based beam combiner, which only recently allowed the required theoretical raw contrast of 10−3 in this spectral range. The VLTI long baseline interferometry enables to reach high angular resolution (4.2 mas at 3.8 μm wavelength with the Auxiliary Telescopes (ATs)), while high contrast detection is achieved using nulling interferometry. This polarisation requires a high degree of optical symmetry between the four pupils of the VLTI, only possible with precise phase, dispersion and intensity control systems. The instrument is currently in its design phase. In this paper, the warm optics design and the injection system up to the photonic chip are presented. The different properties of the design are presented including the optics used, the characteristics of the four beams and the current drawbacks. Particular attention is devoted to the optical alignment and the tolerance analysis in order to estimate the precision required for the alignment procedure and therefore to choose adapted optical mountings.

Background and Purpose Refractory status epilepticus is a clinical emergency associated with high mortality and morbidity. Increasing evidence suggests neuroinflammatory pathways contribute to the development of drug-refractoriness during status epilepticus. The ATP-gated P2X7 receptor (P2X7R) has been described as potential link between inflammation and increased hyperexcitability. The aim of the present study was to determine the contribution of the P2X7R to drug-refractory status epilepticus and its therapeutic potential. Experimental Approach Status epilepticus was induced via a unilateral microinjection of kainic acid into the amygdala in adult mice. Severity of status epilepticus was compared in animals overexpressing or knock-out in the P2X7R, after inflammatory priming by the pre-injection of bacterial lipopolysaccharide (LPS) and in mice treated with P2X7R-targeting and anti-inflammatory drugs. Key Results P2X7R overexpressing mice were unresponsive to several anticonvulsants (lorazepam, midazolam, phenytoin and carbamazepine) during status epilepticus. P2X7R expression was increased in microglia during drug-refractory status epilepticus, P2X7R overexpression led to a pro-inflammatory phenotype in microglia during status epilepticus and the anti-inflammatory drug minocycline restored normal responsiveness to anticonvulsants in P2X7R overexpressing mice. Pre-treatment of wildtype mice with LPS increased P2X7R levels in the brain and promoted the development of pharmaco-resistant status epilepticus, which was overcome by either a genetic deletion of the P2X7R or the administration of the P2X7R antagonists AFC-5128 or ITH15004. Conclusion and Implications Our results demonstrate that P2X7R-induced pro-inflammatory effects contribute to resistance to pharmacotherapy during status epilepticus and suggest therapies targeting the P2X7R as novel adjunctive treatments for drug-refractory status epilepticus.

Introduction: The bleomycin model of lung fibrosis is widely used to evaluate the efficacy of novel anti-fibrotic drugs and nintedanib is an clinically relevant reference control compound. The objectives of this study were to use pharmacokinetic (PK) modelling to predict a nintedanib dose sufficient to provide efficacy in a rat model of repetitive bleomycin dosing and then demonstrate the anti-fibrotic reproducibility of the efficacious nintedanib dose. Methods: Studies were performed in male rats. Pharmacokinetic parameters were determined following administration of nintedanib at 60 mg/kg (QD or BID) and free drug calculations were based on rat lung and plasma protein binding studies. For fibrosis studies, bleomycin was administered to the lung on five occasions; nintedanib or vehicle were administered at 60 mg/kg QD or BID (Day -1 to Day 27). Fibrosis was assessed using the hydroxyproline assay (HP) and modified Ashcroft Score on collagen-stained lung sections. Results: PK modelling of free nintedanib concentrations, relative to cellular potency, suggested that 60 mg/kg BID gave 40-70% target coverage between dose occasions compared to 60 mg/kg QD which gave only 10% target coverage at Ctrough. Consistent with the PK modelling, nintedanib 60 mg/kg BID significantly reduced HP and the fibrosis score in four independent studies while 60 mg/kg, QD, was not consistently anti-fibrotic. Conclusion: An understanding of PK is vital to optimise dose for efficacy studies and nintedanib 60 mg/kg BID is a suitable control reference item in a repetitive bleomycin model of lung fibrosis in the rat.

International audience; We report mid-infrared supercontinuum generation in a silicon germanium-on-silicon waveguide. We show that the dispersion properties of the waveguide can be precisely tuned by controlling the thickness of a chalcogenide cladding layer.

Interstitial Pulmonary Fibrosis (IPF) is a chronic and progressive disease. Fibrosis is caused by aberrant alveolar epithelial cell activation and repair leading to fibroblastic foci, accumulation of extracellular matrix and irreversible destruction of the lung. The objective of this study was to develop a rat model of fibrosis using bleomycin. Mass Spectrometry Imaging (MSI) was used to identify biomarkers in fibrotic lesions. Rats were dosed with one or seven doses of bleomycin delivered to the lungs. Control animals received vehicle. Body weights, clinical signs and respiratory parameters were monitored during the in-life phase. Lungs were fixed for histopathology (Day 21) or for mass spectrometry imaging (MALDI-FTICR) (Day 7 and Day 22). MSI was also used to confirm the distribution of bleomycin after dosing. Bleomycin caused statistically significant changes in respiratory parameters and lung weights, as well as a reduction in body weight gain; all changes were consistent with the development of fibrosis. Histopathological analysis revealed multifocal fibrosis with inflammation. The extent of all changes was greater in those animals administered seven doses of bleomycin compared with one dose. MSI identified the significant upregulation of lipids in fibrotic lesions; some identified lipids are known to be associated with IPF (molecular species of lysophosphatidic acid)(Montesi et al BMC Pulm Med.27;14 2014) while other lipids were novel (with roles in cell signalling, chemotaxis and membrane stability). In conclusion, we have identified a number of known and novel lipid biomarkers in fibrotic lesions in a characterized rat model of IPF induced by bleomycin administration.

The skin is the largest organ in the human body and has the potential to come into contact with a variety of xenobiotics both intentionally (e.g., drugs and cosmetics) or accidentally (e.g., agrochemicals and industrial chemicals). These chemicals may then cross the skin barrier (the stratum corneum) and enter into the systemic circulation where they may produce a desired or an undesired effect, or even no systemic effect at all. Tetrabromodiphenyl ether (TeBDE) is one congener in a mixture of polybrominated diphenyl ethers that makes up a flame-retardant commercial product called pentabromodiphenyl ether (PeBDE). TeBDE was used as a surrogate to assess the potential dermal absorption of this product. The physicochemical properties, including lipophilicity, of TeBDE and PeBDE are similar. Operator exposure of PeBDE product to human skin is possible during production and use. However, during these activities, operators wear protective clothing to protect from or minimize exposure. This study was designed to assess the rate and extent of absorption of [14C]-tetrabromodiphenyl ether ([14C]-TeBDE) through human and rat skin in vitro. [14C]-TeBDE was applied to human and rat split thickness skin membranes in vitro in a single test preparation: [14C]-TeBDE in acetone (ca. 20%, w/v). Dermal delivery and absorbed dose of TeBDE applied to human skin was 3.13% (313 microg equiv/cm(2)) and 1.94% (194 microg equiv/cm(2)) of the applied dose, respectively. Dermal delivery and absorbed dose of TeBDE applied to rat skin was 17.94% (1804 microg equiv/cm(2)) and 14.81% (1489 microg equiv/cm(2)) of the applied dose, respectively. These results confirm that the risk of systemic exposure due to external dermal exposure of the PeBDE product is low in the human. Consequently, based on the toxicological profile of these materials, the potential for undesirable effects is also quite low. The results also confirm that the rat is a conservative model overpredicting human absorption about eight fold.

Evaluation of the safety of new chemicals and pharmaceuticals requires the combination of information from various sources (e.g. in vitro, in silico and in vivo) to provide an assessment of risk to human health and the environment. The authors have identified opportunities to maximize the predictivity of this information to humans while reducing animal use in four key areas; (i) accelerating the uptake of in vitro methods; (ii) incorporating the latest science into safety pharmacology assessments; (iii) optimizing rodent study design in biological development and (iv) consolidating approaches in developmental and reproductive toxicology. Through providing a forum for open discussion of novel proposals, reviewing current research and obtaining expert opinion in each of the four areas, the authors have developed recommendations on good practice and future strategy.