The orbital characters of low-energy electronic structure in iron-chalcogenide superconductor KxFe2-ySe2

The newly discovered iron-chalcogenide superconductorKxFe2ySe2exhibits a distinct electronic structure from other iron-based superconductors.Exploiting polarization-dependent angle-resolved photoemission spectroscopy,we have determined the orbital characters of band structure in aKxFe2ySe2superconductor.To a large extent,we find thatKxFe2ySe2superconductor shares similar orbital characters with other iron-based superconductors,but with its own characteristics.For example,we have resolved two highly degenerate electron cylinders around the zone corner in the s and p geometries,respectively,indicating negligible interactions between them.Moreover,in contrast to the band calculation results,the small electron pocket around Z is found to be mainly consisted of the d z 2 orbital.The determined orbital characters would help to construct a realistic model forKxFe2ySe2.     

An improved method for estimating the activity of a mouse with the photoswitch

Summary A new method for estimating the activity of a mouse by means of the photoswitch is contrived. This device can follow the activity with high fidelity and notable sensitivity, as compared with the conventional method.     

Synthesis of an analog of human calcitonin gene related peptide, [Asu2,7]-h-CGRP

Summary The analog of h-CGRP, des-Ala-deamino-dicarba-h-CGRP, was synthesized by the combination of the conventional solution and the solid phase peptide synthesis methods. This analog showed stronger and longer-lasting hypocalcemic and hypophosphatemic activities than the natural hormone.30 September 1986     

Mice deficient in protein tyrosine phosphatase receptor type Z are resistant to gastric ulcer induction by VacA of Helicobacter pylori

The vacuolating cytotoxin VacA produced by Helicobacter pylori causes massive cellular vacuolation in vitro and gastric tissue damage in vivo, leading to gastric ulcers, when administered intragastrically. Here we report that mice deficient in protein tyrosine phosphatase receptor type Z (Ptprz, also called PTP-zeta or RPTP-beta, encoded by Ptprz) do not show mucosal damage by VacA, although VacA is incorporated into the gastric epithelial cells to the same extent as in wild-type mice. Primary cultures of gastric epithelial cells from Ptprz+/+ and Ptprz-/- mice also showed similar incorporation of VacA, cellular vacuolation and reduction in cellular proliferation, but only Ptprz+/+ cells showed marked detachment from a reconstituted basement membrane 24 h after treatment with VacA. VacA bound to Ptprz, and the levels of tyrosine phosphorylation of the G protein-coupled receptor kinase-interactor 1 (Git1), a Ptprz substrate, were higher after treatment with VacA, indicating that VacA behaves as a ligand for Ptprz. Furthermore, pleiotrophin (PTN), an endogenous ligand of Ptprz, also induced gastritis specifically in Ptprz+/+ mice when administered orally. Taken together, these data indicate that erroneous Ptprz signaling induces gastric ulcers.     

A rapid method for measuring the phospholipid synthetic activity of incubated lymphocytes

Summary A rapid and simple method for estimating the phospholipid synthetic activity of incubated lymphocytes by a Florisil column technique following the uptake of¹⁴C-oleic acid was established. Stimulation of phospholipid synthesis by PHA and inhibitions caused by Tween 20 or Tween 80 and heating were evaluated easily with this method.