The impact of nandrolone decanoate in the osseointegration of dental implants in a rabbit model: Histological and micro-radiographic results

Despite high rates of osseointegration in healthy patients, complex cases present an increased risk of osseointegration failure when treated with dental implants. Furthermore, if immediate loading of the implants is used, maximizing the response of the host organism would be desirable. Anabolic steroids, such as Nandrolone Decanoate (ND), are reported to have beneficial clinical effects on various bone issues such as osteoporosis and bone fractures. However, their beneficial effects in promoting osseointegration in dental implant placement have not been documented. The study aimed to examine histological changes induced by ND in experimental dental implants in rabbit models. Two dental implants were placed in the tibias of 24 adult rabbits. Rabbits were allocated to one of two groups: control group or test group. Rabbits in the latter group were given nandrolone decanoate (15 mg/kg, immediately after implant placement and after 1 week). Micro-radiographic and histological analyses were assessed to characterize the morphological changes promoted by the nandrolone decanoate use. Total bone volume and fluorescence were significantly higher in the control group after 2 weeks. Such a difference between the two groups might indicate that, initially, nandrolone lengthens the non-specific healing period characteristic of all bone surgeries. However, after the beginning of the reparative processes, the quantity of newly formed bone appears to be significantly higher, indicating a positive stimulation of the androgen molecule on bone metabolism. Based on micro-radiology and fluorescence microscopy, nandrolone decanoate influenced bone regeneration in the implant site. The anabolic steroid nandrolone decanoate affects the healing processes of the peri-implant bone and therefore has the potential to improve the outcomes of implant treatment in medically complex patients

Genetic structure and variability within and among populations of the fat-tailed Barbarine sheep breed using microsatellites markers

This study investigates the genetic diversity and the structure of the most dominant native fat-tailed Tunisian sheep breed (Barbarine, BAR) using microsatellite markers. Blood samples from 183 BAR animals, belonging to 4 subpopulations according to phenotypic traits, were collected across all regions in Tunisia. BAR animals and 31 Appenninica Italian sheep breed (APP) used as an out-group were genotyped at 17 microsatellites loci. A total of 270 alleles were identified with average gene diversity equal to 0.812. The mean observed heterozygosity (0.745) and allelic richness (8.09) estimates were high within BAR breed highlighting notable levels of genetic diversity. The low FIS (0.078) and FIT (0.084) values indicate low level of inbreeding within this breed while a low FST estimate (0.007) shows that the subpopulations are not genetically differentiated. The clustering analysis performed with ‘structure’ detected the absence of substructures and the clear uniqueness of the BAR. Tomiuk and Loeschcke’s DTL genetic distance values confirmed the distinction between APP and BAR breeds. Results arising from our microsatellites analysis represent a starting point for the valorization of this indigenous Tunisian sheep breed. A suggestion was made to monitor its genetic variability and for the preservation of this breed for the next generations.Keywords: Tunisian Barbarine sheep breed, microsatellite markers, genetic variability, population structureAfrican Journal of Biotechnology, Vol. 13(1), pp. 44-54, 1 January, 201

Molecular mediators of the association between child obesity and mental health

Biological mechanisms underlying the association between obesity and depression remain unclear. We investigated the role of metabolites and DNA methylation as mediators of the relationship between childhood obesity and subsequent poor mental health in the English Avon Longitudinal Study of Parents and Children. Obesity was defined according to United Kingdom Growth charts at age 7 years and mental health through the Short Mood and Feelings Questionnaire (SMFQ) completed at age 11 years. Metabolites and DNA methylation were measured by nuclear magnetic resonance spectroscopy and Illumina array in blood at the age of 7 years. The associations between obesity and SMFQ score, as continuous count data or using cut-offs to define depressive symptoms (SMFQ >7) or depression (SMFQ >11), were tested using adjusted Poisson and logistic regression. Candidate metabolite mediators were identified through metabolome-wide association scans for obesity and SMFQ score, correcting for false-discovery rate. Candidate DNA methylation mediators were identified through testing the association of putative BMI-associated CpG sites with SMFQ scores, correcting for look-up false-discovery rate. Mediation by candidate molecular markers was tested. Two-sample Mendelian randomization (MR) analyses were additionally applied to test causal associations of metabolites with depression in independent adult samples. 4,018 and 768 children were included for metabolomics and epigenetics analyses, respectively. Obesity at 7 years was associated with a 14% increase in SMFQ score (95% CI: 1.04, 1.25) and greater odds of depression (OR: 1.46 (95% CI: 0.78, 2.38) at 11 years. Natural indirect effects (mediating pathways) between obesity and depression for tyrosine, leucine and conjugated linoleic acid were 1.06 (95% CI: 1.00, 1.13, proportion mediated (PM): 15%), 1.04 (95% CI: 0.99, 1.10, PM: 9.6%) and 1.06 (95% CI: 1.00, 1.12, PM: 13.9%) respectively. In MR analysis, one unit increase in tyrosine was associated with 0.13 higher log odds of depression (p = 0.1). Methylation at cg17128312, located in the FBXW9 gene, had a natural indirect effect of 1.05 (95% CI: 1.01,1.13, PM: 27%) as a mediator of obesity and SMFQ score. Potential biologically plausible mechanisms involving these identified molecular features include neurotransmitter regulation, inflammation, and gut microbiome modulation. These results require replication in further observational and mechanistic studies

The neutral dynamics during the 2009 sudden stratosphere warming simulated by different whole atmosphere models

The present study compares simulations of the 2009 sudden stratospheric warming (SSW) from four different whole atmosphere models. The models included in the comparison are the Ground-to-topside model of Atmosphere and Ionosphere for Aeronomy, Hamburg Model of the Neutral and Ionized Atmosphere, Whole Atmosphere Model, and Whole Atmosphere Community Climate Model Extended version (WACCM-X). The comparison focuses on the zonal mean, planetary wave, and tidal variability in the middle and upper atmosphere during the 2009 SSW. The model simulations are constrained in the lower atmosphere, and the simulated zonal mean and planetary wave variability is thus similar up to approximate to 1 hPa (50 km). With the exception of WACCM-X, which is constrained up to 0.002 hPa (92 km), the models are unconstrained at higher altitudes leading to considerable divergence among the model simulations in the mesosphere and thermosphere. We attribute the differences at higher altitudes to be primarily due to different gravity wave drag parameterizations. In the mesosphere and lower thermosphere, we find both similarities and differences among the model simulated migrating and nonmigrating tides. The migrating diurnal tide (DW1) is similar in all of the model simulations. The model simulations reveal similar temporal evolution of the amplitude and phase of the migrating semidiurnal tide (SW2); however, the absolute SW2 amplitudes are significantly different. Through comparison of the zonal mean, planetary wave, and tidal variability during the 2009 SSW, the results of the present study provide insight into aspects of the middle and upper atmosphere variability that are considered to be robust features, as well as aspects that should be considered with significant uncertainty

p-wave triggered superconductivity in single-layer graphene on an electron-doped oxide superconductor

Electron pairing in the vast majority of superconductors follows the Bardeen-Cooper-Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a $\textit{p}$-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a $\textit{p}$-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.The work was funded by the following agencies: Royal Society (‘Superconducting Spintronics’), Leverhulme Trust (IN-2013-033), Schiff Foundation, the EPSRC (EP/N017242/1, EP/G037221/1, EP/K01711X/1, EP/K017144/1, EP/N010345/1, EP/M507799/1, EP/L016087/1), ERC Grant Hetero2D, EU Graphene Flagship, COST Action MP-1201, MSCA-IFEF-ST No. 656485-Spin3, Outstanding Academic Fellows programme at NTNU, Research Council of Norway (205591, 216700 and 24080)

p-wave triggered superconductivity in single-layer graphene on an electron-doped oxide superconductor

Electron pairing in the vast majority of superconductors follows the Bardeen–Cooper–Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K

p-wave triggered superconductivity in single-layer graphene on an electron-doped oxide superconductor

This is the final version. Available on open access from Nature Research via the DOI in this record.Data availability: The data set generated and analysed during this study are available for access at http://dx.doi.org/10.17863/CAM.6228Electron pairing in the vast majority of superconductors follows the Bardeen–Cooper–Schrieffer theory of superconductivity, which describes the condensation of electrons into pairs with antiparallel spins in a singlet state with an s-wave symmetry. Unconventional superconductivity was predicted in single-layer graphene (SLG), with the electrons pairing with a p-wave or chiral d-wave symmetry, depending on the position of the Fermi energy with respect to the Dirac point. By placing SLG on an electron-doped (non-chiral) d-wave superconductor and performing local scanning tunnelling microscopy and spectroscopy, here we show evidence for a p-wave triggered superconducting density of states in SLG. The realization of unconventional superconductivity in SLG offers an exciting new route for the development of p-wave superconductivity using two-dimensional materials with transition temperatures above 4.2 K.Royal SocietyLeverhulme TrustSchiff FoundationEngineering and Physical Sciences Research Council (EPSRC

Type-III intermittency in a four-level coherently pumped laser

We study a homogeneously broadened four-level model for a coherently pumped laser with pump and laser fields having crossed linear polarizations. For a parameter range of the type explored in the experiments by Tang et al. [Phys. Rev. A 44, R35 (1991)] the system exhibits a family of type-III-intermittency transitions to chaos in which the onset of intermittency is preceded by period-2, period-3, or period-4 states. We find similarities but also differences between the results of our theory and their experimental results

Synthesis of reaction-adapted zeolites as methanol-to-olefins catalysts with mimics of reaction intermediates as organic structure-directing agents

[EN] Catalysis with enzymes and zeolites have in common the presence of well-defined single active sites and pockets/cavities where the reaction transition states can be stabilized by longer-range interactions. We show here that for a complex reaction, such as the conversion of methanol-to-olefins (MTO), it is possible to synthesize reaction-adapted zeolites by using mimics of the key molecular species involved in the MTO mechanism. Effort has focused on the intermediates of the paring mechanism because the paring is less favoured energetically than the side-chain route. All the organic structure-directing agents based on intermediate mimics crystallize cage-based small-pore zeolitic materials, all of them capable of performing the MTO reaction. Among the zeolites obtained, RTH favours the whole reaction steps following the paring route and gives the highest propylene/ethylene ratio compared to traditional CHA-related zeolites (3.07 and 0.86, respectively).Li, C.; Paris, C.; Martínez-Triguero, J.; Boronat Zaragoza, M.; Moliner Marin, M.; Corma Canós, A. (2018). Synthesis of reaction-adapted zeolites as methanol-to-olefins catalysts with mimics of reaction intermediates as organic structure-directing agents. Nature Catalysis. 1(7):547-554. https://doi.org/10.1038/s41929-018-0104-7S54755417Stocker, M. Methanol-to-hydrocarbons: catalytic materials and their behavior. Micro. Mesopor. Mater. 29, 3–48 (1999).Tian, P., Wei, Y., Ye, M. & Liu, Z. Methanol to olefins (MTO): from fundamentals to commercialization. ACS Catal. 5, 1922–1938 (2015).Ilias, S. & Bhan, A. Mechanism of the catalytic conversion of methanol to hydrocarbons. ACS Catal. 3, 18–31 (2013).Olsbye, U. et al. Conversion of methanol to hydrocarbons: how zeolite cavity and pore size controls product selectivity. Angew. Chem. Int. Ed. 24, 5810–5831 (2012).Hemelsoet, K., Van der Mynsbrugge, J., De Wispelaere, K., Waroquier, M. & Van Speybroeck, V. Unraveling the reaction mechanisms governing methanol-to-olefins catalysis by theory and experiment. ChemPhysChem 14, 1526–1545 (2013).Song, W., Haw, J. F., Nicholas, J. B. & Heneghan, C. S. Methylbenzenes are the organic reaction centers for methanol-to-olefin catalysis on HSAPO-34. J. Am. Chem. Soc. 122, 10726–10727 (2000).Arstad, B. & Kolboe, S. The reactivity of molecules trapped within the SAPO-34 cavities in the methanol-to-hydrocarbons reaction. J. Am. Chem. Soc. 123, 8137–8138 (2001).Xu, T. et al. Synthesis of a benzenium ion in a zeolite with use of a catalytic flow reactor. J. Am. Chem. Soc. 120, 4025–4026 (1998).Song, W., Nicholas, J. B., Sassi, A. & Haw, J. F. Synthesis of the heptamethylbenzene cation in zeolite beta: in situ NMR and theory. Catal. Lett. 81, 49–53 (2002).Xu, S. et al. Direct observation of cyclic carbenium ions and their role in the catalytic cycle of the metahnol-to-olefin reaction over chabazite zeolites. Angew. Chem. Int. Ed. 52, 11564–11568 (2013).Chen, J. et al. Elucidating the olefin formation mechanism in the methanol to olefin reaction over AlPO-18 and SAPO-18. Catal. Sci. Tech. 4, 3268–3277 (2014).Haw, J. F. et al. Roles for cyclopentenyl cations in the synthesis of hydrocarbons from methanol on zeolite catalyst HZSM-5. J. Am. Chem. Soc. 122, 4763–4775 (2000).Svelle, S. et al. Conversion of methanol into hydrocarbons over zeolite H-ZSM-5: ethene formation is mechanistically separated from the formation of higher alkenes. J. Am. Chem. Soc. 128, 14770–14771 (2006).Teketel, S., Olsbye, U., Lillerud, K. P., Beato, P. & S., S. Selectivity control through fundamental mechanistic insight in the conversion of methanol to hydrocarbons over zeolites. Micro. Mesopor. Mater. 136, 33–41 (2010).Zhang, M. et al. Methanol conversion on ZSM-22, ZSM-35 and ZSM-5 zeolites: effects of 10-membered ring zeolite structures on methylcyclopentenyl cations and dual cycle mechanism. RSC Adv. 6, 95855–95864 (2016).Sassi, A. et al. Methylbenzene chemistry on zeolite HBeta: multiple insights into methanol-to-olefin catalysis. J. Phys. Chem. B 106, 2294–2303 (2002).Sassi, A., Wildman, M. A. & Haw, J. F. Reactions of butylbenzene isomers on zeolite HBeta: methanol-to-olefins hydrocarbon pool chemistry and secondary reactions of olefins. J. Phys. Chem. B 106, 8768–8773 (2002).Bjørgen, M., Olsbye, U., Petersen, D. & Kolboe, S. The methanol-to-hydrocarbons reaction: insight into the reaction mechanism from [12C]benzene and [13C]methanol coreactions over zeolite H-beta. J. Catal. 221, 1–10 (2004).McCann, D. M. et al. A complete catalytic cycle for supramolecular methanol-to-olefins conversion by linking theory with experiment. Angew. Chem. Int. Ed. 47, 5179–5182 (2008).Arstad, B., Kolboe, S. & Swang, O. Theoretical study of the heptamethylbenzenium ion. intramolecular isomerizations and C2, C3, C4 alkene elimination. J. Phys. Chem. A 109, 8914–8922 (2005).De Wispelaere, K., Hemelsoet, K., Waroquier, M. & Van Speybroeck, V. Complete low-barrier side-chain route for olefin formation during methanol conversion in H-SAPO-34. J. Catal. 305, 76–80 (2013).Wang, C. M., Wang, Y. D. & Xie, Z. K. Verification of the dual cycle mechanism for methanol-to-olefin conversion in HSAPO-34: a methylbenzene-based cycle from DFT calculations. Catal. Sci. Technol. 4, 2631–2638 (2014).Wang, C. M., Wang, Y. D., Liu, H. X., Xie, Z. K. & Liu, Z. P. Theoretical insight into the minor role of paring mechanism in the methanol-to-olefins conversion within HSAPO-34 catalyst. Micro. Mesopor. Mater. 158, 264–271 (2012).Ilias, S. & Bhan, A. The mechanism of aromatic dealkylation in methanol-to-hydrocarbons conversion on H-ZSM-5: What are the aromatic precursors to light olefins? J. Catal. 311, 6–16 (2014).Erichsen, M. W. et al. Conclusive evidence for two unimolecular pathways to zeolite-catalyzed de-alkylation of the heptamethylbenzenium cation. ChemCatChem 7, 4143–4147 (2015).Bhawe, Y. et al. Effect of cage size on the selective conversion of methanol to light olefins. ACS Catal. 2, 2490–2495 (2012).Kang, J. H. et al. Further studies on how the nature of zeolite cavities that are bounded by small pores influences the conversion of methanol to light olefins. ChemPhysChem 19, 412–419 (2018).Martin, N. et al. Nanocrystalline SSZ-39 zeolite as an efficient catalyst for the methanol-to-olefin (MTO) process. Chem. Commun. 52, 6072–6075 (2016).Dusselier, M., Deimund, M. A., Schmidt, J. E. & Davis, M. E. Methanol-to-olefins catalysis with hydrothermally treated zeolite SSZ-39. ACS Catal. 5, 6078–6085 (2015).Yokoi, T., Yoshioka, M., Imai, H. & Tatsumi, T. Diversification of RTH-type zeolite and its catalytic application. Angew. Chem. Int. Ed. 48, 9884–9887 (2009).Ji, Y., Deimund, M. A., Bhawe, Y. & Davis, M. E. Organic-free synthesis of CHA-type zeolite catalysts for the methanol-to-olefins reaction. ACS Catal. 5, 4456–4465 (2015).Liu, M. et al. Differences in Al distribution and acidic properties between RTH-type zeolites synthesized with OSDAs and without OSDAs. Phys. Chem. Chem. Phys. 16, 4155–4164 (2014).Gallego, E. M. et al. “Ab initio” synthesis of zeolites for preestablished catalytic reactions. Science 355, 1051–1054 (2017).Zones, S. I. & Nakagawa, Y. Use of modified zeolites as reagents influencing nucleation in zeolite synthesis. Stud. Surf. Sci. Catal. 97, 45–52 (1995).Li, C., Moliner, M. & Corma, A. Building zeolites from pre-crystallized units: nanoscale architecture. Angew. Chem. Int. Ed. https://doi.org/10.1002/anie.201711422 (2018).Zones, S. I. Zeolite SSZ-13 and its method of preparation. US Patent 4,544,538 (1985).Li, Z., Navarro, M. T., Martínez-Triguero, J., Yu, J. & Corma, A. Synthesis of nano-SSZ-13 and its application in the reaction of methanol to olefins. Catal. Sci. Technol. 6, 5856–5863 (2016).Kumar, M., Luo, H., Román-Leshkov, Y. & Rimer, J. D. SSZ-13 crystallization by particle attachment and deterministic pathways to crystal size control. J. Am. Chem. Soc. 137, 13007–13017 (2015).Martínez-Franco, R., Cantin, A., Moliner, M. & Corma, A. Synthesis of the small pore silicoaluminophosphate STA-6 by using supramolecular self-assembled organic structure directing agents. Chem. Mater. 26, 4346–4353 (2014).Schmidt, J. E., Deimund, M. A., Xie, D. & Davis, M. E. Synthesis of RTH-type zeolites using a diverse library of imidazolium cations. Chem. Mater. 27, 3756–3762 (2015).Moliner, M., Franch, C., Palomares, E., Grill, M. & Corma, A. Cu–SSZ-39, an active and hydrothermally stable catalyst for the selective catalytic reduction of NOx. Chem. Commun. 48, 8264–8266 (2012).Zhao, Y. & Truhlar, D. G. The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals. Theor. Chem. Acc. 120, 215–241 (2008).Ditchfield, R., Hehre, W. J. & Pople, J. A. Self-consistent molecular orbital methods. 9. Extended Gaussian-type basis for molecular-orbital studies of organic molecules. J. Chem. Phys. 54, 724–728 (1971).Hehre, W. J., Ditchfield, R. & Pople, J. A. Self-consistent molecular orbital methods. 12. Further extensions of Gaussian-type basis sets for use in molecular-orbital studies of organic-molecules. J. Chem. Phys. 56, 2257–2261 (1972).Frisch, M. J. et al. Gaussian 09, Revision C.01. (Gaussian, Wallingford, 2009).Van Speybroeck, V. et al. First principle chemical kinetics in zeolites: the methanol-to-olefin process as a case study. Chem. Soc. Rev. 43, 7326–7357 (2014)