We demonstrated crystal structures, magnetic, and optical properties of the B-site substituted double-perovskite Ba 2 Pr(Bi 1− x Sb x ) O 6 (<inline-formula> <tex-math notation="LaTeX">x=0 ...</tex-math></inline-formula>, 0.1, 0.2, 0.25, 0.3, 0.4, 0.5, and 1.0). The single-phase polycrystalline samples with the light Sb substitution are formed in a monoclinic structure (<inline-formula> <tex-math notation="LaTeX">C^{2}/m </tex-math></inline-formula>). The heavily Sb-substituted samples crystallize in the rhombohedral system accompanied by B-site disorder. Magnetization measurements show that the effective magnetic moments are located around <inline-formula> <tex-math notation="LaTeX">3.2~\mu _{B} </tex-math></inline-formula> for the lightly Sb-substituted samples, indicating the valence mixing between Pr 3+ and Pr 4+ . The magnetic moments with the heavy Sb substitution are close to the valence of Pr 3+ . The magnitudes of bandgap energy for the two end-member samples were estimated from the optical measurements to be <inline-formula> <tex-math notation="LaTeX">E_{g} = 0.977 </tex-math></inline-formula> eV at <inline-formula> <tex-math notation="LaTeX">x=0 </tex-math></inline-formula> and 2.395 eV at <inline-formula> <tex-math notation="LaTeX">x=1.0 </tex-math></inline-formula>. The effect of the bandgap opening due to Sb substitution is examined by using the density functional theory. The lightly and heavily Sb-doped compounds show typical absorption edges in indirect and direct semiconductors, respectively. These findings are qualitatively consistent with the calculated results.
To cite this article: Seike M, Furuya K, Omura M, Hamada-Watanabe K, Matsushita A, Ohtsu H. Histamine H₄ receptor antagonist ameliorates chronic allergic contact dermatitis induced by repeated ...challenge. Allergy 2010; 65: 319-326. The present study observed effects of the histamine H₄ receptor on chronic allergic contact dermatitis induced by repeated challenge in mice. Acute contact dermatitis was induced by single epicutaneous challenge of 2,4,6-trinitro-1-chlorobenzene (TNCB) to the ear. Chronic allergic contact dermatitis was developed by repeated epicutaneous challenge using TNCB on the dorsal back skin. H₄ receptor antagonist JNJ7777120 was administered to wild-type mice, while H₄ receptor agonist 4-methylhistamine was administered to histidine decarboxylase (HDC) (-/-) mice that synthesized no histamine. HDC (-/-) mice did not differ phenotypically from HDC (+/+) mice, and H₄ receptor antagonist/agonist did not have clinical effects in terms of acute contact dermatitis reactions. H₄ receptor antagonist ameliorated skin eczematous lesions induced by repeated TNCB challenge in HDC (+/+) mice. On the contrary, H₄ receptor agonist exacerbated skin lesions exclusively in HDC (-/-) mice. Application of H₄ receptor agonist induced migration of mast cells and eosinophils in skin lesions, and H₄ receptor antagonist suppressed these changes. H₄ receptor was immunohistochemically detected on mast cells in eczematous lesions. Levels of interleukin (IL)-4, -5, and -6 in lesions were decreased, whereas levels of interferon-γ and IL-12 were increased by H₄ receptor antagonistic activity. Serum Immunoglobulin E levels rapidly increased with repeated challenge, but decreased with H₄ receptor antagonist. Because chronic allergic contact dermatitis is developed by H₄ receptor stimulation, H₄ receptor antagonists might represent new candidate drugs for treating chronic allergic contact dermatitis.
Retrospective clinical study.
To elucidate the pathophysiology of rapid progressive clinical deterioration following the onset of cervical myelopathy.
Spinal Injuries Center, Fukuoka, Japan.
A total ...of 43 cervical spondylotic myelopathy (CSM) patients were treated surgically by a senior surgeon. All patients showed intramedullary intensity changes on magnetic resonance (MR) imaging. Overall, eight patients suffered rapid progressive clinical deterioration; four of them had obvious anamnesis of minor trauma. We assessed the responsible injured segment by MR T2-weighted images. Clinical instabilities at the focal segment were evaluated using functional sagittal plain radiographs. Neurological evaluations were performed preoperatively and at 12 months postoperatively using American Spinal Injury Association (ASIA) motor scores and Japanese Orthopaedic Association (JOA) scores for cervical myelopathy. Intraoperatively, we evaluated the presence of adhesive scar tissue on the dura mater at the focal segment.
The responsible injured segment was C3-4 in 75% of the rapid progressive (rp)-CSM and in 28.57% of the conventional CSM subjects. One with rp-CSM showed sagittal translational segmental instability. Preoperative ASIA motor scores and JOA scores in the rp-CSM were significantly lower than those in the conventional CSM subjects. Postoperative ASIA motor scores between the subjects showed no significant differences; however, postoperative JOA scores in the rp-CSM subjects were significantly lower. Moreover, an epidural membrane was observed in 62.5% of rp-CSM and 11.4% of conventional CSM subjects.
We hypothesized that the pathophysiology of rp-CSM might be additional cervical cord disorder following the onset of cervical myelopathy. Early decompression surgery is recommended in such patients.
We demonstrated crystal structures, magnetic, thermodynamic and optical properties of the B-site substituted perovskite oxides Ba2Pr(Bi1−x,Sbx) O6 (x=0, 0.1 and 0.2). Polycrystalline samples of ...Sb-substituted Ba2PrBiO6 were prepared with the conventional solid-state reaction technique. The X-ray diffraction data revealed that the polycrystalline samples are an almost single phase with a monoclinic structure (C2 /m). Substitution of smaller Sb ion at Bi site causes a monotonic decrease in both the lattice parameters and volume. Magnetization measurements at high temperatures above 200 K show that the effective magnetic moment is estimated to be around 3.15 µB, which is close to that for Pr3+ion. The X-ray photoemission spectroscopy analysis revealed that a prominent peak of Pr3+ is dominant with a smaller shoulder structure of Pr4+. A Schottky-like anomaly observed in the low-temperature specific heat measurement is explained by low-lying splitting of Pr ions under the crystal field effect. Optical spectra were measured using a diffuse-reflectance method. The band gaps were estimated from the optical data to be 0.977 eV and 1.073 eV, at x = 0 and 0.2, respectively. The effect of band gap opening due to Sb substitution is examined by using the density functional theory.
Huge cervical and mediastinal masses may lead to acute respiratory failure caused by laryngotracheal compression and airway obstruction. Thyroid storm is also a life-threatening endocrine emergency ...originating almost exclusively from uncontrolled Graves' disease. We report a case of a 42-year-old man with acute upper airway obstruction and tachycardia from progressive swelling of a giant thyroid, in conjunction with thyroid storm resulting from uncontrolled Graves' disease. Fibreoptic-assisted nasal intubation was performed while the patient was awake, immediately followed by emergency total thyroidectomy via a cervical and sternal approach. The patient had an uneventful postoperative course and recovered well. Respiratory failure due to swelling of a giant thyroid is a life-threatening condition and should be treated immediately with endotracheal intubation while the patient is awake following emergent total thyroidectomy, even with a sternotomy.
Nuruk is a traditional fermentation starter used for making starch-based Korean alcoholic drinks. The yeast strain Pichia kudriavzevii N77-4 was newly isolated from nuruk. Resistance to ethanol ...stress is a crucial characteristic in alcoholic beverage production, but the ethanol stress-resistance of P. kudriavzevii remains to be clarified. In this study, we attempted to analyze the ethanol resistance of P. kudriavzevii N77-4, and to improve it by ethyl methanesulfonate (EMS) mutagenesis. After 4 h of cultivation in 5% ethanol, N77-4 showed a growth defect accompanied with accumulation of reactive oxygen species (ROS). In addition, exposure of N77-4 to ethanol stress induced a more than 3-fold increase in the expression of PkSOD2, which encodes a superoxide dismutase, indicating that the strain was able to generate PkSOD2 to decrease ROS. EMS mutagenesis was performed to improve the ethanol resistance of N77-4. An isolated mutant, HER8, exhibited higher ethanol resistance, a 50% decrease in ROS accumulation, and enhanced expressions of PkGPX2, which encodes a glutathione peroxidase, and PkSOD1. Moreover, HER8 showed 10% greater ethanol production, indicating that up-regulation of these antioxidant genes is important for improving ethanol resistance in P. kudriavzevii, and use of the HER8 strain will improve the brewing fermentation.
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