C2 peptide

Three ReN(2)phases (Pbcn,C2/mandP4/mbm) are searched to be stable under different pressures by the swarm-intelligence-based CALYPSO method. Pressure-induced phase transitions fromPbcnphase toC2/mphase at 68.5 GPa andC2/mphase toP4/mbmphase at 138.8 GPa are firstly observed. The calculated results of density of state show all the three phases are metallic conductor. And elastic constant calculations confirm their mechanical stabilities. The high bulk and shear moduli ofC2/mandP4/mbmphases indicate their high hardness. The total and partial electron densities of states and electron localization functions indicate that the covalent bonding of Re-N in ReN(2)makes great contributions to the structural stability and high hardness.

Excess iodine may induce and exacerbate autoimmune thyroiditis (AIT) in humans and animals. In order to assess the potential protective mechanisms of selenium (Se) in thyroid autoimmunity, the effects of inorganic Se (sodium selenite) administration on thyroid morphology and follicular cytology were investigated in adult Wistar rats with iodine-induced AIT. A total of 48 adult Wistar rats (24 females, 24 males) were allocated to one of four dietary regimens: C0, control; C1, only potassium iodine (KI); C2, concomitant KI and Se; C3, only KI initially, followed by Se administration. For AIT induction the rats were fed with 0.05% KI for 56 days. Se-treated rats received 0.3 mg/l sodium selenite in drinking water. Thyroid tissues were collected for pathologic diagnosis after 7 days in C0 group, 56 days in C1 and C2 groups, and 112 days in C3 group. In C1 group, moderate to severe thyroiditis was observed in 83% of males and 50% of female rats (P=0.223). In C3 group 16.7% of male rats developed moderate thyroiditis and none in C2 group, whereas no females were identified with moderate to severe thyroiditis in C2 or C3 group. Thus, the administration of Se was proven to have protective effects against thyroiditis cytology in both male and female Wistar rats.