“
“The impurity binding TPCA-1 energy in a polar rectangular quantum wire under an applied electric field is studied by a variational approach. The electron- and ion-longitudinal-optical (LO) phonon interactions are both taken into account in the calculations. The numerical results for the GaAs rectangular quantum

wires show that the binding energies and Stark energy-shift are both sensitive to the size, shape of the wire section, and the position of the impurity. The binding energy increases with decreasing the section area. The LO phonon effect lowers the binding energy of the on-center impurity but raises that of the impurity near the wire surface, and gives a qualitatively similar contribution to the Stark effect. (C) 2011 American Institute of Physics. [doi:10.1063/1.3642973]“
“SHP-2 (encoded by PTPN11) is a ubiquitously expressed protein tyrosine phosphatase required for signal transduction by multiple different cell surface

receptors. Humans with germline SHP-2 mutations develop Noonan syndrome or LEOPARD syndrome, which are characterized by cardiovascular, neurological and skeletal abnormalities. To study how SHP-2 regulates SBE-β-CD tissue homeostasis in normal adults, we used a conditional SHP-2 mouse mutant in which loss of expression of SHP-2 was induced in multiple tissues in response to drug administration. Induced deletion of SHP-2 resulted in impaired hematopoiesis, weight loss and lethality. Most strikingly, induced SHP-2-deficient mice developed severe skeletal Nocodazole inhibitor abnormalities, including kyphoses and scolioses of the spine. Skeletal malformations were associated with alterations in cartilage and a marked increase in trabecular bone mass. Osteoclasts were essentially absent from the bones of SHP-2-deficient mice, thus accounting for the osteopetrotic phenotype. Studies in vitro revealed that osteoclastogenesis that was stimulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappa B ligand (RANKL) was defective in SHP-2-deficient mice. At least in part, this was explained

by a requirement for SHP-2 in M-CSF-induced activation of the pro-survival protein kinase AKT in hematopoietic precursor cells. These findings illustrate an essential role for SHP-2 in skeletal growth and remodeling in adults, and reveal some of the cellular and molecular mechanisms involved. The model is predicted to be of further use in understanding how SHP-2 regulates skeletal morphogenesis, which could lead to the development of novel therapies for the treatment of skeletal malformations in human patients with SHP-2 mutations.”
“Epilepsy in adenylosuccinate lyase deficiency may be difficult to treat, and there is no standardized therapy. The authors describe a case of severe adenylosuccinate lyase deficiency resulting from a heterozygous mutation of the ADSL gene (p.D215H/p.I351T).