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Background: Peutz-Jeghers syndrome (PJS) is a rare disorder characterized by multiple gastrointestinal hamartomatous polyps and mucocutaneous pigmentation. STK11 has been identified as a causative gene for this disease. Case presentation: Herein we report a Chinese Han kindred with PJS. Onset for the PJS signs in three of the patients was rarely as early as at birth. We identified a novel heterozygous mutation (c.440_441delGT, p.Arg147Leufs*15) in the gene STK11, causing a short frameshift followed by a deletion of 63% of the amino acids in the STK protein. This mutation co-segregated with the PJS phenotype, and was absent in two hundred of unrelated ethnicity-matched controls. The mutation led to expression decrease of unaffected STK11 protein in patients than in controls, as well in PJ polyps than in circulating leucocytes from the patients. Phosphorylation levels of the downstream kinase AMPKa altered according with the expression of STK11. These results indicated the possibility that haploinsufficiency and epigenetic reduction of STK11 contributed to the pathogenesis of the disease. Conclusion: This study identifies a novel mutation in the pathogenic gene STK11 leading to PJS. [ABSTRACT FROM AUTHOR]

A new crystal of tetraphenylphosphonium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)-nickelate acetone solvate (BPNI) has been prepared at room temperature and characterized by elemental analysis, UV-Vis-NIR absorption spectrum and X-ray single crystal determination. The complex crystallized in monoclinic space group P2/c with unit cell dimensions a = 24.5350 (6) Å, b = 7.3097 (2) Å, c = 23.1141 (6) Å, β = 115.585 (2)°, V = 3738.89 (17) Å, Z = 4, D .= 1.5081 (1) g cm. The X-ray structure determination revealed that the crystal is centro-symmetrical and there are two halves of independent cations in the molecule. Graphical Abstract: A new crystal of tetraphenylphosphonium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)-nickelate(II) acetone solvate (BPNI) with monoclinic space group P2/c (unit cell dimensions a = 24.5350(6) Å, b = 7.3097(2) Å, c = 23.1141(6) Å, β = 115.585(2)°, V = 3738.89(17) Å, Z = 4, D = 1.5081(1) g cm) has been prepared and characterized by elemental analysis, UV-Vis-NIR absorption spectrum and X-ray single crystal determination.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The third-order nonlinearity of a novel ET[bis(ethylenedithio)-tetrathiafulvalene] complex (ET ⋅ BF3) has been measured by using the Z-scan technique with a laser pulse width of 30 ps at 1064 nm. The third-order nonlinear refractive index (n2), nonlinear absorption coefficient (β) and nonlinear susceptibilities (χ(3)) of a sample acetonitrile solution are 3.5 × 10-11 esu, 1.65 cm/GW and 5.4 × 10-12 esu, respectively. The nonresonant second-order hyperpolarizability (γ) for the molecule has been estimated to be 2.77 × 10-30 esu. The two merit factors for all-optical switching are W ≫ 1 and T = 1.49, respectively. [ABSTRACT FROM AUTHOR]

A new crystal of 4,5-bis(cyclohexanecarbonylthio)-1,3-dithiolane-2-thione has been prepared at room temperature and characterized by elemental analysis, UV–Vis–NIR absorption spectrum and X-ray single crystal determination. The complex crystallized in triclinic space group P-1 with unit cell dimensions a = 5.37370(10) Å, b = 12.8618(2) Å, c = 15.2481(2) Å, α = 74.8530(10)°, β = 80.6000(10)°, γ = 85.9550(10)°, V = 1003.18(3) Å3, Z = 2, Dx = 1.3861(1) g cm−3. The X-ray structure determination revealed that the crystal is centered-symmetrical and the molecules form dimers with a long intermolecular S···S interaction in the crystal. A new crystal of 4,5-bis(cyclohexanecarbonylthio)-1,3-dithiolane-2-thione with triclinic space group P − 1 [unit cell dimensions a = 5.37370(10) Å, b = 12.8618(2) Å, c = 15.2481(2) Å, α = 74.8530(10)º,β = 80.6000(10)º, γ = 85.9550(10)º, V = 1003.18(3) Å3, Z = 2, Dx = 1.3861(1) g·cm−3] has been prepared and characterized by elemental analysis, UV–Vis–NIR absorption spectrum and X-ray single crystal determination. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Formation of neural circuits depends on stable contacts between neuronal processes, mediated by interaction of cell adhesion molecules, including N-cadherin. In the present study, we found that activity-dependent dendrite arborization specifically requires N-cadherin-mediated extracellular neuron-neuron interaction, because the enhancement did not occur for neurons cultured in isolation or plated on an astrocyte monolayer and was abolished by a recombinant soluble N-cadherin ectodomain. Furthermore, depolarization elevated the level of membrane-associated cadherin/catenin complexes and surface N-cadherin. Importantly, surface N-cadherin elevation is specifically required forthe maintenance of nascent dendrite arbors. Through lossand gain-of-function approaches, we showed that N-cadherin-mediated dendrite growth requires association of the cadherin/catenin complex with the actin cytoskeleton. In summary, these results identify a previously unexplored and specific function for activity-induced, N-cadherin-mediated neuron-neuron contacts in the maintenance of dendrite arbors. [ABSTRACT FROM AUTHOR]

The first-principles methods have been employed to calculate the structural, electronic, and mechanical properties of the α, β, and γ phases of uranium under pressure up to 100 GPa. The electronic structure has been viewed in forms of density of states and band structure. The mechanical stability of metal U in the α, β, and γ phases have been examined. The independent elastic constants, polycrystalline elastic moduli, as well as Poisson’s ratio have been obtained. Upon compression, the elastic constants, elastic moduli, elastic wave velocities, and Debye temperature of α phase are enhanced pronouncedly. The value of B/G illustrates that α and γ phases are brittle in ground state. [ABSTRACT FROM AUTHOR]

The ab initio anisotropic Migdal-Eliashberg formalism has been used to examine the pairing mechanism and the nature of the superconducting gap in the recently discovered lithium-decorated monolayer graphene superconductor. Our results provide evidence that the superconducting transition in Li-decorated monolayer graphene can be explained within a standard phonon-mediated mechanism. We predict a single anisotropic superconducting gap and a critical temperature Tc=5.1-7.6K, in very good agreement with the experimental results. [ABSTRACT FROM AUTHOR]