Next step in the development of mesoprogestins: the preclinical profile of EC313.

Introduction: The pharmacological target for progesterone, different progestins, and Selective Progesterone Receptor Modulators (SPRMs) is the nuclear progesterone receptor (PR). EC313 is a new member of a subgroup of SPRMs, mesoprogestins, which combine especially PR- agonistic and PR-antagonistic activities in one molecule. Methods: The suitable in vivo-model for the differentiation of SPRMs from the subgroup of mesoprogestins is the estrogen-primed juvenile rabbit endometrium assay (McPhail Assay). Remarkably, in contrast to other well-known SPRMs with no agonistic effects in this test, EC313 shows clear partial PR-agonistic effects that are higher than that of the well-known mesoprogestin Asoprisnil which already demonstrated remarkable clinical effectiveness for the treatment of uterine fibroids and endometriosis. The findings from the guinea pig studies presented here can be the impetus for further preclinical development of EC313. This model shows the same features for the termination of pregnancy by antiprogestins such as Mifepristone and Ulipristal acetate (UPA) in humans. Moreover, it is possible to distinguish between progestational and anti-progestational activities in the same experiment. Results: The EC313 treatment reveals PR dominance in the genital tract and inhibits unopposed estrogenic effects. In very high doses (30.0 mg/animal/day subcutaneously (s.c.)) given twice on pregnancy days 43 and 44, no premature labor was induced (in contrast to UPA, dosed at 10.0 and 30. mg/animal/day s.c.). The anti-ovulatory activity of EC313 exceeds that of Ulipristal acetate or Mifepristone. EC313 binds to the steroid receptors in vitro with a similar affinity as the natural ligand progesterone. At the glucocorticoid receptor (GR) EC313 acts as a weak inhibitor. Minor activities at the human androgen receptor (AR) and mineralocorticoid receptor (MR) are considered negligible. No binding to the estradiol receptor was detected. In contrast to some in vitro-receptor findings, estrogenic, anti-estrogenic, androgenic, anti-androgenic, glucocorticoid, and anti-glucocorticoid actions were absent in vivo. The tissue selectivity of EC313 was demonstrated previously by reducing the growth and proliferation of uterine fibroids in animal models (lowest effective dosage 0.1 mg/kg/day s.c.).. As shown in this article, the anti-fibroid activity of EC313 was confirmed with a 10 times lower dosage (0.01 mg/kg/day s.c.). It was also shown that EC313 reduces the growth of endometriotic lesions in a human xenograft immune-deficient (NOD-SCID) mice model with a comparatively very low dosage range. In the aforementioned EC313 activity model, UPA was tested as the reference compound, the clinical effectiveness of which has already been demonstrated. Discussion: For an explanation of these findings, the possibility is discussed that the mixed agonistic/antagonistic feature of EC313 is tissue target-specific based on its super-additive synergism characteristic for active bifunctional agents. In conclusion, the specific pharmacodynamic profile of this compound opens the possibility for the development of a drug with a distinct pharmaco-endocrinological profile against uterine fibroids, endometriosis, and other PR-dependent gynecological diseases.

Effect of different levels of copper nanoparticles and copper sulphate on performance, metabolism and blood biochemical profiles in broiler chicken.

A study was conducted to investigate the influence of copper administration in ovo to chicken embryos and/or supplied in drinking water to growing chickens in the form copper nanoparticles (Cu-NP) or copper sulphate (CuSO4 ). The fertilised eggs were assigned to three groups (n = 50 per group): control (not injected), injected with 50 mg/kg Cu-NP or with 50 mg/kg CuSO4 at day 1 of incubation. Thereafter, 126 one-day-old broiler chickens were randomly assigned to seven post-hatched groups: control not injected and not provided with Cu in the drinking water, injected with 50 mg/kg Cu-NP + 20 mg/kg in water, not injected + 20 mg/kg Cu-NP in water, injected with 50 mg/kg CuSO4  + 20 mg/kg in water, not injected + 20 mg/kg CuSO4 in water, injected with 50 mg/kg Cu-NP and injected with 50 mg/kg CuSO4 . The experiment was carried out from day 1 to 35 post-hatching. The in ovo injection of Cu improved the final body weight, average daily gain and feed conversion ratio in relation to the control group. Conversely, the provision of Cu in the drinking water had less of an effect on growth performance in comparison with the injected groups. A significant improvement was shown in energy and nitrogen utilisation, being better for Cu-NP than CuSO4 . The cholesterol, urea and glucose levels in the blood were reduced by Cu-NP treatment in relation to the other groups. The relative weight of the liver was decreased, while bursa of Fabricius was increased in Cu groups in relation to the control group. Cu excretion was only reduced in chickens injected with 50 mg/kg Cu-NP + 20 mg/kg in water. The immune-related genes were not affected by the treatments. The in ovo injection of Cu-NP might improve broiler performance more efficiently than the injection of CuSO4 or the provision of Cu-NP and/or CuSO4 in drinking water.

On the mechanism of mechanochemical molecular encapsulation in peptidic capsules.

Molecular encapsulation of C60 inside a hydrogen-bond-sealed semi-flexible peptidic capsule is hindered in solution, yet it proceeds effectively after mechanical milling of a solid sample. We show that the molecular mechanism involves the generation of non-covalently disordered forms that are active in guest uptake. We also show that the solvent-free mechanochemical covalent synthesis of capsules directly results in obtaining disordered, active forms.

Perceptions of transcatheter device closure of patent ductus arteriosus in veterinary cardiology and evaluation of a canine model to simulate device placement: a preliminary study.

OBJECTIVES: The purpose of this study was to evaluate a canine patent ductus arteriosus (PDA) model developed for practicing device placement and to determine practices and perceptions regarding transcatheter closure of PDA from the veterinary cardiology community. METHOD: A silicone model was developed from images obtained from a dog with a PDA and device placement was performed with catheter equipment and a document camera to simulate fluoroscopy. A total of 36 individuals including 24 diplomates and 12 residents participated, and the feedback was obtained. The study included an initial questionnaire, practice with the model, observation of device placement using the model, and a follow-up questionnaire. RESULTS: A total of 92% of participants including 100% of residents indicated they did not have the opportunity to practice device placement before performing the procedure and obtained knowledge of the procedure from reading journal articles or observation. Participants indicated selecting the appropriate device size (30/36, 83%) and ensuring the device is appropriately positioned before release (18/36, 50%) as the most common areas of difficulty with device placement. Confidence level was higher after practicing with the model for residents when compared with diplomates and for participants that had performed 1-15 procedures when compared with those that had performed >15 procedures. These findings suggest those that have performed fewer procedures may benefit the most from practicing with a model. CONCLUSIONS: This preliminary study demonstrates the feasibility of a PDA model for practicing device placement and suggests that there is a potential benefit from providing additional training resources.

A chiral member of the family of organic hexameric cages.

A cubic nanocage (O symmetry) that exhibits inherent chirality and has a covalent, rigid skeleton with molecule-sized entrance portals was obtained by means of dynamic covalent chemistry using a reaction between aldehyde-functionalized resorcin[4]arene and hydrazine.

Shape memory polymers with visible and near-infrared imaging modalities: Synthesis, characterization and in vitro analysis.

Shape memory polymers (SMPs) are promising for non-invasive medical devices and tissue scaffolds, but are limited by a lack of visibility under clinical imaging. Fluorescent dyes are an alternative to radiocontrast agents in medical applications, they can be utilized in chemical sensors and monitors and may be anti-microbial agents. Thus, a fluorescent SMP could be a highly valuable biomaterial system. Here, we show that four fluorescent dyes (phloxine B (PhB), eosin Y (Eos), indocyanine green(IcG), and calcein (Cal)) can be crosslinked into the polymer backbone to enhance material optical properties without alteration of shape memory and thermomechanical properties. Examinations of the emission wavelengths of the materials compared with the dye solutions showed a slight red shift in the peak emissions, indicative of crosslinking of the material. Quantitative analysis revealed that PhB enabled visibility through 1 cm of blood and through soft tissue. We also demonstrate the utility of these methods in combination with radio-opaque microparticle additives and the use of laser-induced shape recovery to allow for rapid shape recovery below the glass transition temperature. The crosslinking of fluorescent dyes into the SMP enables tuning of physical properties and shape memory and independently of the fluorescence functionality. This fluorescent SMP biomaterial system allows for use of multiple imaging modalities with potential application in minimally invasive medical devices.

Unique magnetic and thermoelectric properties of chemically functionalized narrow carbon polymers.

We analyze magnetic, transport and thermoelectric properties of narrow carbon polymers, which are chemically functionalized with nitroxide groups. Numerical calculations of the electronic band structure and the corresponding transmission function are based on density functional theory. Transport and thermoelectric parameters are calculated in the linear response regime, with particular interest in charge and spin thermopowers (charge and spin Seebeck effects). Such nanoribbons are shown to have thermoelectric properties described by large thermoelectric efficiency, which makes these materials promising from the application point of view.

Spectacular enhancement of thermoelectric phenomena in chemically synthesized graphene nanoribbons with substitution atoms.

We analyze theoretically the transport and thermoelectric properties of graphene nanoribbons of a specific geometry, which have been synthesized recently from polymers [Cai, et al., Nature, 2011, 466, 470]. When such nanoribbons are modified at one of the two edges by Al or N substitutions, they acquire a ferromagnetic moment localized at the modified edge. We present numerical results on the electronic structure and thermoelectric properties (including also spin thermoelectricity) of the modified nanoribbons. The results show that such nanoribbons can display large thermoelectric efficiency in certain regions of chemical potential, where the corresponding electric and spin figures of merit achieve unusually large values. The enhancement of thermoelectric efficiency follows from a reduced phonon heat conductance of the nanoribbons and from their peculiar electronic band structure. Thus, such nanoribbons are promising for practical applications in nanoelectronic and spintronic devices.

¹9F nuclear magnetic resonance screening of glucokinase activators.

Human hexokinase enzyme IV (EC 2.7.1.1) catalyzes the phosphorylation of glucose and regulates the level of glucose. This enzyme exhibits strong positive cooperativity due to an allosteric transition between an inactive form and a closed active form. This form can be stabilized by activators and, thus, can increase its turnover by a kinetic memory effect characterized by a slow decay to the inactive state. The structural details of this kinetic allostery are known. Several synthetic activators have been reported. We present a preliminary nuclear magnetic resonance (NMR) screening of a chemical library in search of molecules with some affinity for glucokinase (GK). The library, composed of eight molecules with known activity as well as molecules that display no interaction, has been tested using the FAXS (fluorine chemical shift anisotropy and exchange for screening) method, based on monitoring the R2 relaxation of the (19)F spin. To ensure a valid interaction measurement, the enzyme was placed in the presence of glucose and magnesium. The binding signal of one known fluorinated ligand was measured by determining the displacement of the known ligand. This simple measure of the (19)F signal intensity after an 80-ms spin echo correlates nicely with the EC50, opening a route for NMR screening of GK activators.

Spin effects in thermoelectric phenomena in SiC nanoribbons.

Using ab initio methods we calculate the thermoelectric and spin thermoelectric properties of zigzag SiC nanoribbons, asymmetrically terminated with hydrogen. Such nanoribbons display a ferromagnetic ground state, with edge magnetic moments oriented in parallel. Both thermopower and spin thermopower have been determined as a function of chemical potential and temperature. To find the thermoelectric efficiency, the total heat conductance has been calculated, i.e. the electronic and phonon contributions. Numerical results for SiC nanoribbons are compared with those for graphene and silicene ones.

Enhanced thermoelectric efficiency in ferromagnetic silicene nanoribbons terminated with hydrogen atoms.

Using ab initio methods we calculate thermoelectric and spin thermoelectric properties of silicene nanoribbons with bare, mono-hydrogenated and di-hydrogenated edges. Asymmetric structures, in which one edge is either bare or di-hydrogenated while the other edge is mono-hydrogenated (0H-1H and 2H-1H nanoribbons), have a ferromagnetic ground state and display remarkable conventional and spin thermoelectric properties. Strong enhancement of the thermoelectric efficiency, both conventional and spin ones, results from a very specific band structure of such nanoribbons, where one spin channel is blocked due to an energy gap while the other spin channel is highly conductive. In turn, 0H-2H and 2H-2H nanoribbons (with one edge being either bare or di-hydrogenated and the other edge being di-hydrogenated) are antiferromagnetic in the ground state. Accordingly, the corresponding spin channels are equivalent, and only conventional thermoelectric effects can occur in these nanoribbons.

Bone marrow-origin stem/progenitor cells in the mammary gland of heifers.

The aim of the study was to estimate the size of bone marrow-origin stem/progenitor population in 2-year old nonpregnant Holstein-Friesian heifers. Quantitative and qualitative analysis was done using scanning cytometry and confocal microscopy of mammary tissue slices labelled with the combination of two markers: Sca-1 (marker of stem-progenitor cells) and CD45 (marker of hematopoietic cells). The average (+/- SEM) percentage of Sca-1POS CD45 POS cells was 0.89 +/- 0.21. They were localized mainly outside of mammary ducts, in the stroma and sometimes intraluminally. Our results indicate that the subpopulation of Sca-1POS cells bearing CD45 antigen may enrich the niche of mammary stem/progenitor cells from the bone marrow and participate in the growth of the mammary gland in post-pubertal heifers.

2D∕3D registration algorithm for lung brachytherapy.

PURPOSE: A 2D∕3D registration algorithm is proposed for registering orthogonal x-ray images with a diagnostic CT volume for high dose rate (HDR) lung brachytherapy. METHODS: The algorithm utilizes a rigid registration model based on a pixel∕voxel intensity matching approach. To achieve accurate registration, a robust similarity measure combining normalized mutual information, image gradient, and intensity difference was developed. The algorithm was validated using a simple body and anthropomorphic phantoms. Transfer catheters were placed inside the phantoms to simulate the unique image features observed during treatment. The algorithm sensitivity to various degrees of initial misregistration and to the presence of foreign objects, such as ECG leads, was evaluated. RESULTS: The mean registration error was 2.2 and 1.9 mm for the simple body and anthropomorphic phantoms, respectively. The error was comparable to the interoperator catheter digitization error of 1.6 mm. Preliminary analysis of data acquired from four patients indicated a mean registration error of 4.2 mm. CONCLUSIONS: Results obtained using the proposed algorithm are clinically acceptable especially considering the complications normally encountered when imaging during lung HDR brachytherapy.

Sci-Thur AM: Planning - 06: Planning target volume margin suitability in lung stereotactic body radiation therapy: A preliminary evaluation using cone-beam computed tomography.

Stereotactic body radiation therapy (SBRT) requires precise delivery of radiation to the target; intra- and inter-fraction lung tumour motion may adversely impact local tumour control. The purpose of this study was to retrospectively evaluate the impact of planning target volume (PTV) margin size on the coverage of the internal target volume (ITV) as localized in pre- and post-treatment cone-beam computed tomography (CBCT) images. Data from two patients undergoing SBRT were evaluated. For planning, free-breathing and 4DCT scans were performed, and used to contour the ITV. A 5mm margin was added to create the PTV. During treatment, 14 CBCTs were collected pre- and post-beam delivery. A data set comprising the average 4DCT intensities where available and treatment planning CT intensities for voxels that were beyond the field of view of the 4DCT was constructed. Registration of the combined planning image to each CBCT was performed using a deformable image registration algorithm. The transformations aligning the combined planning image with the CBCTs were applied to the planning ITV to obtain the treatment ITVs. For each CBCT, the fraction of treatment ITV within the PTV was determined using Boolean logic. This was repeated for various PTV margins ranging from 0 to 10 mm at 1mm intervals. The 3 and 5 mm PTV margins covered 95.1 ± 5.9% and 99.0 ± 2.0% of the ITV, respectively. Analysis of additional patients will be performed to confirm these preliminary results, which reinforce the use of a 5mm PTV margin for lung SBRT.

Poster - Thur Eve - 28: Optimization of a prostate cancer IGRT protocol.

Our image-guided radiation therapy (IGRT) protocol for post-prostatectomy patients involves acquiring a kV cone beam computed tomography (CBCT) dataset at each fraction and shifting the treatment couch to align the surgical clips. This IGRT strategy requires significant resources, and delivers non-negligible dose to normal tissues. The objective of this work is to evaluate this IGRT protocol against two alternative strategies in terms of the dose-volume statistics for target and organ at risk regions. Our method involves deforming the planning CT to the CBCT dataset acquired at each fraction, computing dose on the deformed dataset, and inversely transforming the dose back onto the original planning CT dataset. The treatments of six patients were evaluated assuming three IGRT scenarios: no IGRT, daily IGRT using the clinically employed couch shifts, and alternating day IGRT. The doses delivered to the clinical target volumes are within approximately 3.2, 1.3, and 2.1% of the plan for the non-IGRT, daily, and alternating day IGRT protocols, respectively. Doses to relevant portions of the organs at risk deviate from the plan by up to 10.5, 13.1 and 10.7% for non-IGRT, daily IGRT, and alternating day IGRT protocols, respectively. Some cases do not differ significantly between IGRT and non-IGRT protocols in terms of cumulative DVHs, highlighting the difficult task of correcting prostate bed deformations via the treatment couch translations. In general, the alternating day IGRT protocol was found to result in a clinically insignificant deviation in delivered dose while providing a significant reduction in resource use and patient imaging dose.

Poster - Thur Eve - 65: Optimization of an automatic image contouring system for radiation therapy.

Intensity modulated radiation therapy (IMRT) is an advanced technique used to concentrate the prescribed dose in the tumour while minimizing exposure to healthy tissues. Success in IMRT is greatly dependent upon the localization of the target volume and normal tissue, thus accurate contouring is crucial. In this paper, we describe an automated atlas-based image contouring system and our approach for improving the system by performing a full-scale optimization of registration parameters using high-performance computing. To achieve this, we use manually pre-contoured CT images of ten head and neck patients. For any parameter set, each patient data is registered with the remaining patients. Accuracy of the resulting contours is determined automatically by comparing their overlap with manually defined targets using Dice's similarity coefficient (DSC). This allows us to compare all permutations of the image registration parameter sets and input data to investigate their impact on final contour accuracy. Investigating the parameter space required 27,000 image registrations and 216,000 DSC computations. To perform these registrations we introduced a large cluster of high-performance computers and developed a parallel testing harness. The metrics collected from the tests show a wide range of performance, indicating that parameter selection is crucial in our contouring system. By selecting an optimized parameter set, we increased the mean overlap of the automatically contoured regions of interest by 50% and reduced registration time by 50% compared to the original parameters. Our findings illustrate that full-scale optimization is an effective method for improving the performance of the automated image contouring system.

Lipopolysaccharide from Porphyromonas gingivalis stimulates rat mast cells to cysteinyl leukotriene generation and upregulates Toll-like receptor -2 and -4 expression.

Mast cells are found in all tissues of the oral cavity and it is suggested that they take part in the development of oral inflammation. As Porhyromonas gingivalis is widely recognized as a major pathogen in the development and progression of gingivitis and periodontitis, the aim of our study is to determine the effect of P. gingivalis lipopolysaccharide (LPS) on mast cell degranulation, cysteinyl leukotriene (cysLT) generation, and migration, as well as Toll-like receptor (TLR)-2 and -4 expression. Experiments were carried out in vitro on rat peritoneal mast cells. LPS-induced mast cell histamine release was estimated by a spectrofluorometric method and cysLT generation by ELISA test. Mast cell migration in response to this antigen was examined according to Boyden's modified method and TLR expression was determined by flow cytometry. We found that P. gingivalis LPS did not induce mast cell degranulation and histamine release. However, activation of mast cells with this bacterial antigen resulted in generation and release of significant amounts of cysLTs. We also documented that LPS from P. gingivalis did not stimulate mast cell migration, even in the presence of laminin, whereas it strongly upregulated TLR2 and TLR4 expression on mast cells. Observations that P. gingivalis LPS activates mast cells to generate and release proinflammatory mediators such as cysLTs and modulates TLR2 and TLR4 expression indicates that these cells might be involved in the emergency of inflammatory processes evolved in response to P gingivalis infection.

Enhancement of thermoelectric efficiency in a two-level molecule.

Electron and energy transport through a two-level molecule (quantum dot) with intra- and inter-level Coulomb correlations is studied using the non-equilibrium Green function formalism. Thermoelectric coefficients are determined in the regime of linear transport for a wide range of gate voltages and temperature. At low temperatures Coulomb blockade effects lead to oscillations of thermal conductance which are well correlated with oscillations in electron conductance. Due to different probabilities of particular one- and two-particle configurations, the intensities of the peaks corresponding to resonant states are different, which results in the selection of channels active in the transport. Additional selection can be obtained for molecules with level-dependent tunnelling rates to external electrodes. In such systems, channels with strongly reduced heat transfer can appear, which results in an enhancement of the thermal efficiency.

Differential effects of in vivo PPAR alpha and gamma activation on fatty acid transport proteins expression and lipid content in rat liver.

Peroxisome proliferator-activated receptors (PPAR;s) serve as lipid sensors and when activated modify gene expression of proteins highly involved in the regulation of fatty acid metabolism. Recently, the accumulation of lipids in liver was shown to be depended on the excessive protein-mediated transmembrane transport of long chain fatty acids (LCFAs). The aim of the present study was to determine the in vivo effects of PPARalpha and gamma activation at two levels: 1) on the expression of fatty acid transporters, 2) on the content and fatty acids saturation status of lipids in rats liver. PPARalpha agonist (WY 14,643) treatment upregulated the liver expression of FAT/CD36 (+20%, p<0.05) and did not significantly affect the content of FABPpm and FATP-1. Accordingly there was a significant increase in the content of phospholipid (+12%, p<0.05), diacylglycerol (+65%, p<0.05) and triacylglycerol (+46%, p<0.05) fractions followed PPARalpha activation. In contrast, pioglitazone (PPARgamma agonist) had no effect on the content of fatty acid transporters (FAT/CD36, FABPpm and FATP-1) as well as the content of liver lipid fractions with the exception for triacylglycerols, which have been reduced significantly (-89%, p<0.05). These findings suggest that in vivo PPARalpha and PPARgamma activation exert different effects on both the expression of fatty acid transporters and lipid content in rat's liver.

Chronic, in vivo, PPARalpha activation prevents lipid overload in rat liver induced by high fat feeding.

PURPOSE: Peroxisome proliferator-activated receptors (PPAR's) are lipid sensors and when activated they modify gene expression of proteins regulating fatty acid (FA) metabolism in liver cells. The aim of the present study was to examine the in vivo effects of PPAR alpha and gamma activation combined with high fat diet (HFD) feeding on the lipid content and FA profile in the liver. MATERIAL/METHODS: We assessed whether in vivo activation of PPARs (alpha or gamma) affects lipid accumulation in the liver induced by HFD feeding. Furthermore, as PPAR activity may be a key factor regulating long chain fatty acids (LCFA) flux and subsequent LCFA utilization in the liver, we prompted to investigate also the FA profile in different lipid fractions in this tissue. RESULTS: PPARalpha agonist (WY 14,643) treatment reduced the accumulation of liver lipids free fatty acids (FFA:-30%, diacylglycerols DAG: -27% and triacylglycerols TAG: -60%, p<0.05) evoked by HFD feeding. Interestingly, with PPARgamma stimulation liver lipid content was further elevated comparing to the effects of HFD (phospholipids PL: +48%, DAG: +231%, TAG: +346%, p<0.05). CONCLUSIONS: These findings suggest that in vivo PPARalpha and PPARgamma activation combined with HFD feeding exert different effects on lipid content in rat's liver and in vivo PPARalpha activation may prevent lipid overload in the liver cells provoked by HFD feeding.