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Notes: Chemical analysis and x-ray diffraction measurements of samples during the reaction of cobalt treatment were carried out to study the mechanism of reaction. X-ray diffraction, TEM observation, and magnetic measurements of core γ-Fe2O3 and the modified particles were performed to investigate the crystal growth of cobalt ferrite on core γ-Fe2O3 particles. From chemical analysis of Fe2+ and total-iron ions in the reacting suspension and x-ray diffraction measurements of samples during the reaction, it is clear that the lattice constant becomes larger due to the formation of cobalt ferrite on core γ-Fe2O3 without decrement of Fe2+/total-iron ratio. So, cobalt ferrite on core γ-Fe2O3 particles is formed not by the oxidation of added Fe2+ ions, but by the electron transfer from Fe(OH)2 to core material. From x-ray diffraction measurements, I400/I311, I220/I311, and I111/I311 were calculated. While I400/I311 and I220/I311 are almost constant, only I111/I311 increases with increasing the amount of cobalt and ferrous ions added. These results show that cobalt ferrite is preferentially grown on (111) plane which is the close-packed plane of spinel lattice.

Notes: Multilayers of Pt/C, W/Si, and W/B4C have been developed as a reflector and dispersive element to be applied to the beamline optical system of the synchrotron radiation (SR) in 1- to 20-A region. Pt/C(2d=105 A, N=10) overcoated with Pt(d=100 A) is useful in a glazing incidence optics, which makes it possible to extend the wavelength region to the shorter side at the fixed incidence angle. W/Si(2d=53 A, N=200) and W/B4C(2d=31 A, N=300) are utilized as a dispersive element of double-crystal monochromator (DXM). The second order of Bragg reflection of W/Si is matched to the first order of KAP(2d=26.6 A) crystal. The characterization of these multilayers was carried out by using characteristic x rays and monochromatized SR in 1.5–8 keV. DXM was made of a combination of W/Si and KAP and a pair of W/B4C. Multilayers are used as the first crystal to protect the damage of the crystal caused by the strong irradiation of SR. A pair of W/B4C is aimed at getting high throughput. The energy resolution of these combinations was evaluated with Na–K absorption edge of NaCl around 1.07 keV, which was a bit poor compared to a pair of beryl crystals.

Notes: A holographic SiC grating has been fabricated by means of reactive ion beam etching in Ar+CHF3 mixture and by using photoresist as an etching mask. The etch rates of SiC and photoresist depend on the CHF3 concentration in Ar+CHF3 mixture. A maximum value for a ratio of the etch rate of SiC to that of photoresist was found to be 1.29 for 67%Ar+33%CHF3 mixture. Diffraction efficiency of an ion-beam etched grating of 1200 l/mm grooves coated with Au was measured by using synchrotron radiation and the Al kα emission line from an x-ray tube. The diffraction efficiency of the first order was 4.5%–9.3% in the soft x-ray region between 8.34 and 120 A(ring) with a small amount of the higher order and the scattered light components. In addition, it is demonstrated that SiC can be etched in SF6 gas by synchrotron radiation excitation.

Notes: Multilayer reflectors and position sensitive detectors have been developed in constructing imaging optical systems in the 45–300 A(ring) region. Molybdenum-silicon (2d=140 A(ring), N=20) and nickel–carbon (2d=100 A(ring), N=20) multilayers were deposited on a spherical mirror (25 cm in diameter) for the normal incidence and on a segment of paraboloidal mirror (20 cm×10 cm) for 30° grazing incidence. Their optical characteristics were evaluated by using characteristic x rays and monochromatized synchrotron radiation in the 45–300 A(ring) region. A position sensitive detector is made of a tandem microchannel plate (MCP) with a CsI photocathode and resistive plate, which is placed at the focal plane of each mirror. The detection efficiency and position resolution were measured by using characteristic x rays of CKα and monochromatized synchrotron radiation in the 45–200 A(ring) region.

Notes: Background Allergic airway eosinophilia is suppressed by cysteinyl leukotriene (CysLT) receptor (CysLT1 receptor) antagonists in several species including humans and guinea-pigs, suggesting that CysLTs are directly or indirectly involved in induction of the response.Objective We examined the effect of CysLT antagonists (pranlukast and MCI-826) on antigen inhalation-induced eosinophilia in peripheral blood and lung, and on IL-5 activity in serum during late increase of airway resistance (late asthmatic response, LAR) in sensitized guinea-pigs.Methods Guinea-pigs inhaled ovalbumin (OVA) + Al(OH)3 and OVA mists alternately for sensitization and challenge, respectively, once every 2 weeks. At the fifth challenge, the effects of CysLT antagonists and an anti-IL-5 antibody (TRFK-5) on the occurrence of LAR, and blood and lung eosinophilia, which appeared at 5 h after challenge, were examined. The time-course of IL-5 activity in the serum after the challenge was evaluated by measuring in vitro‘eosinophil survival prolongation activity’. The influence of CysLT antagonists on IL-5 activity was assessed.Results CysLT antagonists and TRFK-5 completely abolished blood and lung eosinophilia. LAR was suppressed by both MCI-826 and TRFK-5 by 40–50%. Sera obtained from sensitized, challenged animals 3 h and 4 h after challenge induced an obvious prolongation of eosinophil survival. The activity of the sera was completely neutralized by prior exposure to TRFK-5, suggesting that it reflected IL-5 activity. Increased IL-5 activity in the serum was inhibited by both pranlukast and MCI-826 by over 90%.Conclusions CysLTs produced after antigen provocation sequentially induced IL-5 production from some immune component cells via CysLT1 receptor activation. Thus, it is likely that CysLTs indirectly cause antigen-induced eosinophilia through IL-5 production.

Notes: Background Previous studies have shown that rat peritoneal mast cells and mast cell model rat basophilic leukaemia (RBL-2H3) cells generate intracellular reactive oxygen species (ROS) in response to antigen challenge. However, the physiological significance of the burst of ROS is poorly understood.Objective The present study was undertaken to investigate the role of superoxide anion in mediator release in rat and human cell systems.Methods RBL-2H3 cells were directly stimulated with anti-rat FcεRI α-subunit monoclonal antibody (mAb). For the analysis of human cell system, leucocytes were isolated by dextran sedimentation from healthy volunteers or from patients, and challenged either with anti-human FcεRI mAb or with the relevant antigens. Superoxide generation was determined by chemiluminescence-based methods. The releases of histamine and leukotrienes (LT)s were determined by enzyme-linked immunosorben assay (ELISA).Results Cross-linking of FcεRI on RBL-2H3 cells or on human leucocytes from healthy donors by the anti-FcεRI mAb resulted in a rapid generation of superoxide anion, as determined by chemiluminescence using superoxide-specific probes. Similarly, leucocytes from patients generated superoxide anion in response to the challenge with the relevant allergen but not with the irrelevant allergen. Furthermore, diphenyleneiodonium (DPI), a well-known inhibitor of flavoenzymes suppressed the superoxide generation and the release of histamine and LTC4 induced by the anti-FcεRI mAb or by allergen in parallel.Conclusion These results indicate that both RBL-2H3 cells and human basophils generate superoxide anion upon FcεRI cross-linking either by antibody or by allergen challenge and that blockade of the generation prevents the release of allergic mediators. The findings strongly support the role of superoxide generation in the activation of mast cells and basophils under both physiological and pathological conditions. The findings suggest that drugs regulating the superoxide generation have potential therapeutic use for allergic disorders.

Notes: Background, aims: The present study was undertaken to assess the periodontal status of a rural Japanese population and to study the correlation between the periodontal status and the serum antibody titers for Porphyromonas gingivalis (Pg) fimbriae.Method: A total of 236 individuals were examined for their periodontal conditions by the use of the community periodontal index for treatment needs (CPITN), and serum antibody titers for Pg fimbriae in their peripheral blood samples were evaluated using the enzyme-linked immunosorbent assay.Results: There was a substantially larger proportion of edentulous subjects in the age group older than 60 years. The remaining teeth were 24.1, 23.2, 11.1 and 10.1 per person in the 40–49, 50–59, 60–69 and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 age groups, respectively. The % of sextants with a CPITN code of missing sextant (MS) increased towards elderly and reached 〉60% in the age group of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 years, as the % of the CPITN 2, 1 or 0 sextant decreased. The % of CPITN 4 and 3 sextants did not differ between different age groups and were about 6–8% and 15–20%, respectively. The % of CPITN 1 or 0 sextants was higher in female subjects than in male subjects in the 60–69 and 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280311:ges" location="ges.gif"/〉70 age groups, while the % of CPITN 4 or 3 sextants was higher in male subjects than in female subjects in all age groups. There was no significant difference between various age groups in the mean serum antibody titers for Pg fimbriae. The mean anti-Pg fimbriae antibody titers was significantly higher for the subjects with a maximum CPITN code 4 (max.-CPITN 4 subject) than for the subjects with lower maximum CPITN codes. The antibody titers varied extensively among the max.-CPITN 4 or 3 subjects, but not among the max.-CPITN 2/1/0 or MS subjects.Conclusions: The present study demonstrated that tooth loss is a remarkable event in elderly subjects and that oral prophylaxis and mechanical debridement should be mandatory in the population examined. It was also demonstrated that the serum antibody titers against Pg fimbriae could be useful for screening individuals with moderate to severe periodontitis.

Notes: Total TIMP-1 concentration in whole saliva of periodontally diseased subjects, 137 ± 67 ng/ml (mean ± SD), was clearly lower (p 〈 0.001) than that of clinically healthy subjects, 273±145, and that of edentulous subjects, 332±121. On the contrary, both active [1.58±0.35 units/ml (mean ± SD)] and total (2.08 ± 0.25) collagenase activities inTIMP-1-free whole saliva of diseased subjects were significantly higher than the activities (0.14 ± 0.14 and 0.50 ± 0.27, respectively) in TIMP-1-free whole saliva of healthy subjects. Most of the total collagenase in whole saliva of healthy subjects consisted of procollagenase, while mainly active collagenase was present in whole saliva from patients with periodontal diseases. Significant reciprocal changes of TIMP-1 and collagenase levels, that is, increase in TIMP-1 concentration and decrease in collagenase activity, were observed after the initial therapy of periodontitis patients.