The Influence of Hyperactivity of the Hypothalamic-pituitary-adrenal Axis and Hyperglycemia on the 5-HT2A Receptor-mediated Wet-dog Shake Responses in Rats

Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis induces hyperglycemia and serotonin (5-HT)2A receptor supersensitivity. In the present study, to investigate the effect of hyperglycemia on the function of 5-HT2A receptors, we compared the 5-HT2A receptor-mediated wet-dog shake responses in rats treated with adrenocorticotropic hormone (ACTH), dexamethasone and streptozotocin. ACTH (100 &#956;g/rat per day, s.c.), dexamethasone (1 mg/kg per day, s.c.) and streptozotocin (60 mg/kg, i.p.) produced significant hyperglycemia at 14 days after the start of these treatments, and the hyperglycemia was most pronounced in the streptozotocin-treated rats. The wet-dog shake responses induced by (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a 5-HT2A receptor agonist, were significantly enhanced at 14 days after repeated treatment with ACTH and dexamethasone. However, streptozotocin-induced diabetes had no effect on the wet-dog shake responses. The results of the present study suggest that hyperglycemia is not strongly associated with the enhanced susceptibility of 5-HT2A receptors under the condition of hyperactivity of the HPA axis.</p

A New Cation-Ordered Structure Type with Multiple Thermal Redistributions in Co₂InSbO₆

Cation ordering in solids is important for controlling physical properties and leads to ilmenite (FeTiO(3)) and LiNbO(3) type derivatives of the corundum structure, with ferroelectricity resulting from breaking of inversion symmetry in the latter. However, a hypothetical third ABO(3) derivative with R32 symmetry has never been observed. Here we show that Co(2)InSbO(6) recovered from high pressure has a new, ordered‐R32 A(2)BCO(6) variant of the corundum structure. Co(2)InSbO(6) is also remarkable for showing two cation redistributions, to (Co(0.5)In(0.5))(2)CoSbO(6) and then Co(2)InSbO(6) variants of the ordered‐LiNbO(3) A(2)BCO(6) structure on heating. The cation distributions change magnetic properties as the final ordered‐LiNbO(3) product has a sharp ferrimagnetic transition unlike the initial ordered‐R32 phase. Future syntheses of metastable corundum derivatives at pressure are likely to reveal other cation‐redistribution pathways, and may enable ABO(3) materials with the R32 structure to be discovered

Effects of Physical and Psychological Stress on 5-HT2A Receptor-mediated Wet-dog Shake Responses in Streptozotocin-induced Diabetic Rats.

Several epidemiological and clinical studies have indicated that the prevalence of psychiatric disorders is higher in diabetic patients than in the general population. In the present studies, we examined the behavioral changes in streptozotocin-induced diabetic rats, and investigated the effects of physical and psychological stress on the hippocampal BDNF levels and on the serotonin 2A (5-HT2A) receptor-mediated wet-dog shake responses. The streptozotocin (60 mg/kg, i.p.)-induced diabetes had no significant effects on the immobility time in the forced swim test or on locomotor activity in the open-field test. Moreover, there was no significant difference in the wet-dog shake responses induced by DOI, a 5-HT2A receptor agonist, between nondiabetic and diabetic rats. Five-day exposure to physical (electric footshock) and psychological (non-footshock) stress had no signifi cant effect on the hippocampal BDNF level in diabetic or nondiabetic rats. The 2 types of stress had no significant effect on the DOI-induced wet-dog shake responses in nondiabetic rats. In diabetic rats, the repeated exposure to physical stress markedly increased the DOI-induced wet-dog shake responses, but the repeated exposure to psychological stress had no effect. These results suggest that exposure to physical stress augmented the susceptibility to the wet-dog shake responses to 5-HT2A receptor stimulation in streptozotocin-induced diabetic rats

Orthogonal antiferromagnetism to canted ferromagnetism in CaCo₃Ti₄O₁₂ quadruple perovskite driven by underlying kagome lattices

AA′₃B₄O₁₂ quadruple perovskites, with magnetic A′ and non-magnetic B cations, are characterized by a wide range of complex magnetic structures. These are due to a variety of competing spin-exchange interactions up to the fourth nearest neighbours. Here, we synthesize and characterize the magnetic behaviour of the CaCo₃Ti₄O₁₂ quadruple perovskite. We find that in the absence of an external magnetic field, the system undergoes antiferromagnetic ordering at 9.3 K. This magnetic structure consists of three interpenetrating mutually orthogonal magnetic sublattices. Under an applied magnetic field, this antiferromagnetic structure evolves into a canted ferromagnetic structure. In explaining these magnetic structures, as well as the seemingly unrelated magnetic structures found in other quadruple perovskites, we suggest a crucial role played by the underlying kagome lattices in these systems. All observed magnetic structures of these materials represent indeed one of the three possible ways to reduce spin frustration in the A′ site kagome layers. More specifically, our survey of the magnetic structures observed for quadruple perovskites AA′₃B₄O₁₂ reveals the following three ways to reduce spin frustration, namely to make each layer ferromagnetic, to adopt a compromise 120° spin arrangement in each layer, or to have a magnetic structure with a vanishing sum of all second nearest-neighbour spin exchanges

Shortened cataract surgery by standardisation of the perioperative protocol according to the Joint Commission International accreditation: a retrospective observational study

OBJECTIVES: To investigate the impact of standardisation of the perioperative protocol based on the Joint Commission International (JCI) accreditation guidelines for operating time in cataract surgery. DESIGN: Retrospective observational study. SETTING: Single centre in Japan. PARTICIPANTS: Between March 2014 and June 2016, 3127 patients underwent cataract surgery under topical anaesthesia including 2581 and 546 patients before and after JCI accreditation, respectively. PRIMARY AND SECONDARY OUTCOMES: We compared three time periods, comprising the preprocedure/surgery time (pre-PT), PT and post-PT, and total PT (TPT) of cataract surgery between patients before and after JCI accreditation, by regression analysis adjusted for age, sex and cataract surgery-associated confounders. RESULTS: The main outcomes were pre-PT, PT, post-PT and TPT. Pre-PT (19.8+/-10.5 vs 13.9+/-8.5 min, p \u3c 0.001) and post-PT (3.5+/-4.6 vs 2.6+/-2.1 min, p \u3c 0.001) significantly decreased after JCI accreditation, while PT did not significantly change (16.8+/-6.7 vs 16.2+/-6.3 min, p=0.065). Consequently, TPT decreased on average by 7.3 min per person after JCI accreditation (40.1+/-13.4 vs 32.8+/-10.9 min, p \u3c 0.001). After adjusting for confounders, pre-PT (beta=-5.82 min, 95% CI -6.75 to -4.88), PT (beta=-0.76 min, 95% CI -1.34 to -1.71), post-PT (beta=-0.85 min, 95% CI -1.24 to -0.45) and TPT (beta=-7.43 min, 95% CI -8.61 to -6.24) were significantly shortened after JCI accreditation. CONCLUSION: Perioperative protocol standardisation, based on JCI accreditation, shortened TPT in cataract surgery under local anaesthesia

Slow oxidation of magnetite nanoparticles elucidates the limits of the Verwey transition

Magnetite (Fe3O4) is of fundamental importance as the original magnetic material and also for the Verwey transition near T_V = 125 K, below which a complex lattice distortion and electron orders occur. The Verwey transition is suppressed by strain or chemical doping effects giving rise to well-documented first and second-order regimes, but the origin of the order change is unclear. Here, we show that slow oxidation of monodisperse Fe3O4 nanoparticles leads to an intriguing variation of the Verwey transition that elucidates the doping effects. Exposure to various fixed oxygen pressures at ambient temperature leads to an initial drop to TV minima as low as 70 K after 45-75 days, followed by recovery to a constant value of 95 K after 160 days that persists in all experiments for aging times up to 1070 days. A physical model based on both doping and doping-gradient effects accounts quantitatively for this evolution and demonstrates that the persistent 95 K value corresponds to the lower limit for homogenously doped magnetite and hence for the first order regime. In comparison, further suppression down to 70 K results from inhomogeneous strains that characterize the second-order region. This work demonstrates that slow reactions of nanoparticles can give exquisite control and separation of homogenous and inhomogeneous doping or strain effects on an nm scale and offers opportunities for similar insights into complex electronic and magnetic phase transitions in other materials.Comment: 24 pages, 13 figures, 2 tables, the manuscript is accepted for publishing at Nature Communication