Cd-content and temperature dependences of hyperfine fields in CdxFe3-xO4

Cd-content and temperature dependences of hyperfine fields in CdxFe3-xO4 (0 ≤ x ≤ 0.5) were investigated by means of time-differential perturbed angular correlation spectroscopy with the 111Cd(←111In) probe. It was found that Cd2+ ions selectively occupy the tetrahedral A site in the spinel structure in all the range of the present Cd content x. The magnetic transition temperature TC becomes lower with increasing x due to the interference of the long-range ordering of Fe spins as a result of expansion of the lattice constants by Cd doping. The measurement of room-temperature hyperfine fields at different x shows that the supertransferred magnetic hyperfine field (SMHF) at the probe decreases as x increases in the range of 0 ≤ x ≤ 0.5. Isothermal measurements at 15 K revealed a contrastive phenomenon for the Cd contents up to x = 0.4: the SMHF becomes great with increasing x; however, this increasing trend of the SMHF turns to reduction at x = 0.46. These observations can be explained based on the effect of Cd doping on the antiferromagnetic coupling between Fe ions in the A and B sites.

Direct adhesion between Cu foil and polytetrafluoroethylene without increasing surface roughness for high-frequency printed wiring boards

Polytetrafluoroethylene (PTFE) serves as a suitable dielectric substrate for high-frequency printed wiring boards (PWBs) owing to its excellent properties at high frequency. However, to the best of our knowledge, no study has investigated the strong adhesion between PTFE and Cu foil with low surface roughness. Therefore, in this study, pure-PTFE comprising a weak boundary layer (WBL) on the surface and glass-cloth-containing PTFE (GC-PTFE), which did not contain a WBL, were subjected to heat-assisted plasma (HAP) treatment. Thereafter, we investigated the surface chemical bonding state, surface morphology, and adhesion properties of the as-prepared PTFE toward Cu foil with low surface roughness. As observed, oxygen-containing functional groups were generated on the HAP-treated PTFE, and the WBL in the as-received pure-PTFE was eliminated via HAP treatment. Moreover, the surface roughness of the HAP-treated PTFE did not increase compared to that of as-received PTFE. After performing thermal compression under atmospheric conditions, the adhesion strength of both HAP-treated pure-PTFE and GC-PTFE was ∼0.9 N mm-1. In addition, the adhesion strength of Cu/pure-PTFE and Cu/GC-PTFE increased after thermal compression under a reduced pressure, and the adhesion strength of 1 N mm-1 was obtained. Although the Cu foil was not roughened, Cu/PTFE realized strong adhesive strength. The developed method is advantageous because maintaining a low interface roughness is crucial for applying PTFE to manufacture high-frequency PWBs.

Surface modification and adhesive-free adhesion of polytetrafluoroethylene (PTFE) and silicone gel containing oleophilic SiO2 powder by plasma treatment

Polytetrafluoroethylene (PTFE) has high-frequency characteristics and low transmission loss, and is expected to be used as a substrate material of printed wiring board for high-frequency applications. Meanwhile, silicone gel has superior properties such as attaching/detaching, weather resistance, and human safety. If the PTFE and silicone gel can be strongly adhered to, they can be applied to internet of things (IoT) devices that can be attached and detached freely. However, adhesion between PTFE, which has poor adhesion, and silicone gel, which has low mechanical strength, is difficult and has not been reported. In this study, PTFE was modified with heat-assisted plasma treatment, and silicone gel was treated with oleophilic SiO₂ powder to improve elastic modulus and modified with plasma jet treatment, and then bonded without adhesive. The adhesion strength of PTFE/silicone gel assembly was 1.13 N mm^-1 when treated moderately, but only 0.01 N mm^-1 when untreated and treated excessively. To investigate the factors causing the difference in the adhesion strength, the surface of silicone gel was evaluated by water contact angle measurement, Fourier transform infrared spectroscopy, and confocal laser scanning microscopy. When treated moderately, hydrophilic functional groups and cross-linking were most frequently increased. Furthermore, when treated excessively, surface degradation was observed, which was expected to lower the adhesion strength. The adhesive-free bonding between PTFE and silicone gel can open a new path for developing IoT devices that can be freely attached and detached.

Effect of Polymer Substrate on Adhesion of Electroless Plating in Irradiation-Based Direct Immobilization of Pd Nanoparticles Catalyst

Pd nanoparticles were directly immobilized on acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile-styrene copolymer (AS), polystyrene (PS), polyphenylene sulfide (PPS), poly(vinyl chloride) (PVC), polypropylene (PP), and polyethylene (PE) polymer substrates via chemical reactions induced by ionizing irradiation. X-ray photoelectron spectroscopy analysis revealed that the chemical state of the immobilized Pd nanoparticles depended on the polymer substrate type. Electroless plating was performed using the immobilized Pd nanoparticles as the catalyst, and Cu-plating films were deposited on all polymer substrates. The results of the tape-peeling test suggested that the chemical state of the immobilized Pd nanoparticles on the polymer substrates affected the plating adhesion strength. Notably, ABS with immobilized Pd particles exhibited a high adhesion strength beyond the practical level, even without prior chemical etching. It was presumed that the high adhesion strength was owing to the anchoring effect of the holes generated on the ABS surface by ionizing irradiation.

Development of Direct Immobilization Technique of Ag Nanoparticles on Resin Substrates Imparting High Antibacterial and Antiviral Activities

A new method has been developed to impart the antimicrobial activity of silver nanoparticles to resin substrates. A resin substrate immersed in an aqueous solution of silver nitrate was irradiated with gamma ray or high energy electron beams. Silver nanoparticles were successfully immobilized on the resin surface directly by chemical reactions induced by ionizing radiation. It was experimentally confirmed that various resin materials, such as acrylonitrile-butadiene-styrene, polyethylene, polypropylene, polyvinyl chloride, and polycarbonate, were applicable for this process. The effects of gamma ray or electron beam irradiation on resin substrates were almost negligible since the irradiation dose was equal or less than that used for sterilization. Despite the small amount of Ag loadings, the obtained samples showed high antibacterial and antiviral activities.

Adhesive-Free Adhesion between Plasma-Treated Glass-Cloth-Containing Polytetrafluoroethylene (GC–PTFE) and Stainless Steel: Comparison between GC–PTFE and Pure PTFE

In this study, the effect of plasma treatment on glass-cloth-containing polytetrafluoroethylene (GC–PTFE) was investigated. Previous plasma studies investigated pure PTFE (which does not contain glass cloth) but not GC–PTFE. The effect of Ar + H2O plasma treatment on GC–PTFE was investigated. The Ar + H2O plasma-treated GC–PTFE sheets were thermally compressed to stainless steel (SUS304) foils without using adhesive, and the GC–PTFE/SUS304 adhesion strengths were measured using a 90° peel test. The adhesion strength increased with the increase in the plasma treatment time (0.8 and 1.0 N/mm at 20 s and 300 s, respectively). Thus, strong adhesion between GC–PTFE/SUS304 was achieved without adhesive. This improvement in the adhesion properties of GC–PTFE can be attributed to the generation of oxygen-containing functional groups and the decrease in the surface roughness of the samples. Thereafter, the adhesion properties of GC–PTFE and pure PTFE were compared. Because, unlike pure PTFE, GC–PTFE has no weak boundary layer, GC–PTFE exhibited better adhesion properties than pure PTFE under short plasma treatment times.

Flexible selection of the functional-group ratio on a polytetrafluoroethylene (PTFE) surface using a single-gas plasma treatment

During plasma treatment of polymers, etching occurs and functional groups are introduced on their surface.

Effects of He and Ar Heat-Assisted Plasma Treatments on the Adhesion Properties of Polytetrafluoroethylene (PTFE)

Heat-assisted plasma (HAP) treatment using He gas is known to improve the adhesive-bonding and adhesive-free adhesion properties of polytetrafluoroethylene (PTFE). In this study, we investigated the effects of He and Ar gaseous species on the HAP-treated PTFE surface. Epoxy (EP) adhesive-coated stainless steel (SUS304) and isobutylene-isoprene rubber (IIR) were used as adherents for the evaluation of the adhesive-bonding and adhesive-free adhesion properties of PTFE. In the case of adhesive bonding, the PTFE/EP-adhesive/SUS304 adhesion strength of the Ar-HAP-treated PTFE was the same as that of the He-HAP-treated PTFE. In the case of adhesive-free adhesion, the PTFE/IIR adhesion strength of the Ar-HAP-treated PTFE was seven times lower than that of the He-HAP-treated PTFE. The relation among gaseous species used in HAP treatment, adhesion properties, peroxy radical density ratio, surface chemical composition, surface modification depth, surface morphology, surface hardness, and the effect of irradiation with vacuum ultraviolet (VUV) and UV photons were investigated. The different adhesive-free adhesion properties obtained by the two treatments resulted from the changes in surface chemical composition, especially the ratios of oxygen-containing functional groups and C-C crosslinks.

Strong Biomimetic Immobilization of Pt-Particle Catalyst on ABS Substrate Using Polydopamine and Its Application for Contact-Lens Cleaning with H2O2

Polydopamine (PDA)-a known adhesive coating material-was used herein to strongly immobilize a Pt-particle catalyst on an acrylonitrile-butadiene-styrene copolymer (ABS) substrate. Previous studies have shown that the poor adhesion between Pt particles and ABS surfaces is a considerable problem, leading to low catalytic durability for H2O2 decomposition during contact-lens cleaning. First, the ABS substrate was coated with PDA, and the PDA film was evaluated by X-ray photoelectron spectroscopy. Second, Pt particles were immobilized on the PDA-coated ABS substrate (ABS-PDA) using the electron-beam irradiation reduction method. The Pt particles immobilized on ABS-PDA (Pt/ABS-PDA) were observed using a scanning electron microscope. The Pt-loading weight was measured by inductively coupled plasma atomic emission spectroscopy. Third, the catalytic activity of the Pt/ABS-PDA was evaluated as the residual H2O2 concentration after immersing it in a 35,000-ppm H2O2 solution (the target value was less than 100 ppm). The catalytic durability was evaluated as the residual H2O2 concentration after repeated use. The PDA coating drastically improved both the catalytic activity and durability because of the high Pt-loading weight and strong adhesion among Pt particles, PDA, and the ABS substrate. Plasma treatment prior to PDA coating further improved the catalytic durability.

Influence of air contamination during heat-assisted plasma treatment on adhesion properties of polytetrafluoroethylene (PTFE)

Plasma surface treatment is typically not effective on fluoropolymers containing polytetrafluoroethylene (PTFE). It is reported that heat-assisted plasma (HAP) treatment at high temperatures (above 200 °C) under atmospheric pressure helium (He) plasma improves the adhesion properties of PTFE. In this study, we investigated the influence of the air concentration during HAP treatment on the adhesion properties of PTFE. Air concentration was controlled via ambient air inflow amount, in other words, base pressure. The PTFE samples HAP-treated in different air concentrations were thermally compressed with an unvulcanized isobutylene-isoprene rubber (IIR). Then, the PTFE/IIR adhesion strength was measured via T-peel test. We show that, when PTFE was HAP-treated in 0.01% air, its PTFE/IIR adhesion strength was over 2 N mm-1; the IIR underwent cohesion failure. However, the PTFE/IIR adhesion strength drastically decreased in the presence of air contamination. The relationships between air concentration during HAP treatment, adhesion properties of PTFE, surface chemical composition, surface morphology, and surface hardness were investigated and discussed.

Improved Catalytic Durability of Pt-Particle/ABS for H₂O₂ Decomposition in Contact Lens Cleaning

In a previous study, Pt nanoparticles were supported on a substrate of acrylonitrile⁻butadiene⁻styrene copolymer (ABS) to give the ABS surface catalytic activity for H₂O₂ decomposition during contact lens cleaning. Although the Pt-particle/ABS catalysts exhibited considerably high specific catalytic activity for H₂O₂ decomposition, the catalytic activity decreased with increasing numbers of repeated usage, which meant the durability of the catalytic activity was low. Therefore, to improve the catalytic durability in this study, we proposed two types of pretreatments, as well as a combination of these treatments before supporting Pt nanoparticles on the ABS substrate. In the first method, the ABS substrate was etched, and in the second method, the surface charge of the ABS substrate was controlled. A combination of etching and surface charge control was also applied as a third method. The effects of these pretreatments on the surface morphology, surface chemical composition, deposition behavior of Pt particles, and Pt loading weight were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), cross-sectional SEM, and inductively coupled plasma atomic emission spectroscopy (ICP-AES), respectively. Both etching and controlling the surface charge effectively improved the catalytic durability for H₂O₂ decomposition. In addition, the combination treatment was the most effective.

Adhesive-free adhesion between heat-assisted plasma-treated fluoropolymers (PTFE, PFA) and plasma-jet-treated polydimethylsiloxane (PDMS) and its application

Conventional low-temperature plasma treatment was reported to minimally improve the adhesion property of polytetrafluoroethylene (PTFE), whereas heat-assisted plasma (HAP) treatment significantly improved the same. An unvulcanized rubber was previously used as an adherent for PTFE. This study aimed to achieve strong adhesive-free adhesion between PTFE and vulcanized polydimethylsiloxane (PDMS) rubber. As-received vulcanized PDMS rubber did not adhere to HAP-treated PTFE, and as-received PTFE did not adhere to vulcanized rubber of plasma-jet (PJ) treated PDMS rubber; however, HAP-treated PTFE strongly adhered to vulcanized PJ-treated PDMS rubber, and both PTFE and PDMS exhibited cohesion failure in the T-peel test. The surface chemical compositions of the PTFE and PDMS sides were determined using X-ray photoelectron spectroscopy. The strong PTFE/PDMS adhesion was explained via hydrogen and covalent bond formation (C–O–Si and/or C(=O)–O–Si) between hydroxyl (C–OH) or carboxyl (C(=O)–OH) groups of the HAP-treated PTFE. This process was also applied to adhesive-free adhesion between a tetrafluoroethylene–perfluoroalkylvinylether copolymer (PFA) and PDMS; subsequently, a translucent PFA/PDMS assembly with strong adhesion was realized together with the PTFE/PDMS assembly. Strong adhesive-free adhesion between fluoropolymers (PTFE, PFA) and vulcanized PDMS rubber without using any adhesives and graft polymer was successfully realized upon plasma treatment of both the fluoropolymer and PDMS sides. Additionally, a PDMS sheet, which was PJ-treated on both sides, was applied to strongly adhere fluoropolymers (PTFE, PFA) to materials such as metal and glass. PJ-treated PDMS was used as an intermediate layer rather than a strong adhesive, achieving PTFE/PDMS/metal and PTFE/PDMS/glass assemblies. The PTFE/PDMS, PDMS/metal, and PDMS/glass adhesion strengths exceeded 2 N/mm.

Characterization of a Panel of Monoclonal Antibodies to Human Coagulation Factor XI and Detection of Factor XI in Hep G2 Cell Conditioned Medium

We have produced a panel of ten monoclonal antibodies specific to coagulation factor XI. Western blot analysis demonstrates that 9 of these antibodies react with the heavy chain of factor XI and one with the light chain. Seven of these antibodies inhibit factor XI and factor XIa activity.

We have used immobilised monoclonal antibody for the production of factor XI deficient plasma and to purify factor XI to homogeneity with high yield in a simple two-step procedure. These monoclonal antibodies were used to develop highly sensitive immunoassays capable of detecting less than 0.01 u factor XI antigen ml−1. A strong correlation was found between antigen and activity levels in 11 patients with hereditary deficiency indicating that none was cross-reacting material positive. Cultured Hep G2 cells were found to synthesize small amounts of factor XI antigen and this could also be detected by functional assay and by western blot analysis.

Optimization of Gas Composition Used in Plasma Chemical Vaporization Machining for Figuring of Reaction-Sintered Silicon Carbide with Low Surface Roughness

In recent years, reaction-sintered silicon carbide (RS-SiC) has been of interest in many engineering fields because of its excellent properties, such as its light weight, high rigidity, high heat conductance and low coefficient of thermal expansion. However, RS-SiC is difficult to machine owing to its high hardness and chemical inertness and because it contains multiple components. To overcome the problem of the poor machinability of RS-SiC in conventional machining, the application of atmospheric-pressure plasma chemical vaporization machining (AP-PCVM) to RS-SiC was proposed. As a highly efficient and damage-free figuring technique, AP-PCVM has been widely applied for the figuring of single-component materials, such as Si, SiC, quartz crystal wafers, and so forth. However, it has not been applied to RS-SiC since it is composed of multiple components. In this study, we investigated the AP-PCVM etching characteristics for RS-SiC by optimizing the gas composition. It was found that the different etching rates of the different components led to a large surface roughness. A smooth surface was obtained by applying the optimum gas composition, for which the etching rate of the Si component was equal to that of the SiC component.

129 Embryo Production from Fully Grown and Growing Stage Oocytes in Japanese Black Calves

Before fattening of Japanese Black female calves, the ovaries are sometimes removed and discarded. Production of embryos from the oocytes residing in such ovaries is beneficial for the rescue of genetic resources. The aim of this study was to establish an embryo production system using oocytes collected from the ovaries of calves just before fattening and to investigate the correlation between the developmental competence of oocytes and the onset of puberty. Ovaries were collected from Japanese Black calves (9.5 ± 0.1 months old, n = 30, 3 replicates) in a fattening farm and separated according to the presence or absence of corpus luteum as the indicator of puberty (CL+ and CL– groups, respectively). Immature fully grown oocytes (IM oocytes), ~120 μm in diameter, were aspirated from follicles of 2 to 6 mm in diameter (CL+; n = 132, CL–; n = 41) and cultured for 22 to 23 h for maturation (IVM). After in vitro fertilization (IVF) for 6 h (designated Day 0), the oocytes were cultured for 9 days (in vitro culture, IVC) (Matoba et al. 2014 J. Dairy Sci. 97, 743-753). Growing oocytes, ~100 μm in diameter, were also collected by dissecting the follicles smaller than 1 mm in diameter. The growing oocytes were cultured for 14 days on membrane inserts for in vitro growth (IVG) (Hirao et al. 2013 Biol. Reprod. 89, 1-11). Then, IVG oocytes (CL+; n = 29, CL–; n = 32) were subjected to IVM, IVF, and IVC. Presumptive zygotes were cultured individually in microwells in culture dishes. Mitochondrial DNA (mtDNA) copy numbers (COX1 gene) of oocytes were examined (Takeda et al. 2010 Mitochondrion 10, 137-142). A comparison was made between the oocytes derived from calf ovaries and those of oocytes collected from cow ovaries by transvaginal ovum pick-up or by aspiration of the ovaries obtained at a local slaughterhouse. In IM oocytes, the rate of embryos developed to the blastocyst stage on Day 7 to 9 was higher in the CL+ group than in the CL– group (38.9 ± 2.6 v. 10.0 ± 7.1%, respectively; P < 0.05, t-test). However, IVG oocytes were compared, there was no significant difference in the blastocyst formation rate between the CL+ or CL– groups (34.7 ± 5.2 v. 19.8 ± 10.1%, respectively). The mtDNA copy numbers of matured oocytes were similar between IM and IVG oocytes irrespective of the maturity of the donor animals. In conclusion, we demonstrated the possibility of embryo production by IVM/IVF/IVC using fully grown and growing oocytes that are present in the ovaries of calves before fattening. Puberty positively affected the developmental competence of IM oocytes but the effect was not significant in IVG oocytes. Utilisation of both fully grown oocytes and growing oocytes may double the chance of rescuing genetic resources of high-breeding-value calves. This study was partly supported by grants from the Ito Foundation. We thank staff at Mie-Katoubokujou for allowing access to calves’ ovaries.

Radiolytic Synthesis of Pt-Particle/ABS Catalysts for H₂O₂ Decomposition in Contact Lens Cleaning

A container used in contact lens cleaning requires a Pt plating weight of 1.5 mg for H₂O₂ decomposition although Pt is an expensive material. Techniques that decrease the amount of Pt are therefore needed. In this study, Pt nanoparticles instead of Pt plating film were supported on a substrate of acrylonitrile-butadiene-styrene copolymer (ABS). This was achieved by the reduction of Pt ions in an aqueous solution containing the ABS substrate using high-energy electron-beam irradiation. Pt nanoparticles supported on the ABS substrate (Pt-particle/ABS) had a size of 4-10 nm. The amount of Pt required for Pt-particle/ABS was 250 times less than that required for an ABS substrate covered with Pt plating film (Pt-film/ABS). The catalytic activity for H₂O₂ decomposition was estimated by measuring the residual H₂O₂ concentration after immersing the catalyst for 360 min. The Pt-particle/ABS catalyst had a considerably higher specific catalytic activity for H₂O₂ decomposition than the Pt-film/ABS catalyst. In addition, sterilization performance was estimated from the initial rate of H₂O₂ decomposition over 60 min. The Pt-particle/ABS catalyst demonstrated a better sterilization performance than the Pt-film/ABS catalyst. The difference between Pt-particle/ABS and Pt-film/ABS was shown to reflect the size of the O₂ bubbles formed during H₂O₂ decomposition.

Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment

A polytetrafluoroethylene (PTFE) surface was modified using atmospheric pressure plasma treatment under heating (heat-assisted plasma treatment) to promote its direct adhesion to isobutylene–isoprene rubber (IIR) without any adhesives.

Correction: Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment

Correction for ‘Adhesive-free adhesion between polytetrafluoroethylene (PTFE) and isobutylene–isoprene rubber (IIR) via heat-assisted plasma treatment’ by Y. Ohkubo et al., RSC Adv., 2017, 7, 6432–6438.

Observation of coherent phonon-plasma coupled modes in wide gap semiconductors by transmission pump-probe measurements

We have investigated coherent LO phonon properties in zinc-based II-VI widegap semiconductors, focusing on phonon-plasma coupled modes. By a careful treatment of the time evolution of the signals in ZnS, ZnSe, and ZnTe, we found a frequency upshift as the pump intensity increases. Using a classical coupled oscillator model, we have explained the pump intensity dependence of both the shift and the decay rates by a mixing of highly damped two-photon generated plasma. From the linear dependence between them we can estimate the photo-excited carrier mobilities, leading to a new powerful estimation method to measure the mobility.

X-ray-induced reduction of Au ions in an aqueous solution in the presence of support materials and in situ time-resolved XANES measurements

Synchrotron X-ray-induced reduction of Au ions in an aqueous solution with or without support materials is reported. To clarify the process of radiation-induced reduction of metal ions in aqueous solutions in the presence of carbon particles as support materials, in situ time-resolved XANES measurements of Au ions were performed under synchrotron X-ray irradiation. XANES spectra were obtained only when hydrophobic carbon particles were added to the precursor solution containing Au ions. Changes in the shape of the XANES spectra indicated a rapid reduction from ionic to metallic Au in the precursor solution owing to synchrotron X-ray irradiation. In addition, the effects of the wettability of the carbon particles on the deposited Au metallic spots were examined. The deposited Au metallic spots were different depending on the relationship of surface charges between metal precursors and support materials. Moreover, a Au film was obtained as a by-product only when hydrophilic carbon particles were added to the precursor solution containing the Au ions.

Possible roles of the AP-1 site in the cytosolic T3 binding protein promoter and insights into its physiological significance

Cytosolic 3,5,3'-triiodo-l-thyronine-binding protein plays pivotal roles in the regulation of intracellular 3,5,3'-triiodo-l-thyronine concentration in vivo. The expression of the protein, which is identical to μ-crystallin, is regulated by various factors. To elucidate the mechanisms of its expression, we evaluated the promoter transactivity and insulin signaling via the AP-1 site in the promoter. The isolated 600 bp human and 1976 bp mouse 5'-flanking regions were cloned in a luciferase reporter plasmid. The luciferase activity was estimated in GH3, dRLh-84, HEK293, and insulin receptor-overexpressing CHO-IR cells. The effects of 12-O-tetradecanoylphorbol 13-acetate and insulin on μ-crystallin mRNA expression were evaluated in various cells. The region between -200 and the transcriptional start site was crucial for constitutive expression in μ-crystallin-expressing dRLh-84 cells. This region contained an AP-1 site. 12-O-Tetradecanoylphorbol 13-acetate increased the level of μ-crystallin mRNA expression in HEK 293 cells. The compound also increased luciferase activity through the promoter. Mutation in the AP1 site diminished the response to the compound. The promoter was also activated by insulin treatment in CHO-IR cells. Insulin treatment increased μ-crystallin mRNA expression in Raw264.7 cells, but decreased in HEK293, P19, and dRLH-84 cells. The expression of μ-crystallin was regulated through the AP-1 site in the promoter. The signals related to AP-1 activation, such as insulin signaling may have diverse effects on μ-crystallin mRNA expression.

Measures against increased environmental radiation dose by the TEPCO Fukushima Dai-ichi NPP accident in some local governments in the Tokyo metropolitan area: focusing on examples of both Kashiwa and Nagareyama cities in Chiba prefecture

The accident of the Fukushima Dai-ichi nuclear power plant of Tokyo Electric Power Cooperation (TEPCO) after the great east Japan earthquake (11 March 2011) elevated the background level of environmental radiation in Eastern Japan. Around the Tokyo metropolitan area, especially around Kashiwa and Nagareyama cities, the ambient dose equivalent rate has been significantly increased after the accident. Responding to strong requests from citizens, the local governments started to monitor the ambient dose equivalent rate precisely and officially, about 3 months after the accident had occurred. The two cities in cooperation with each other also organised a local forum supported by three radiation specialists. In this article, the activities of the local governments are introduced, with main focus on radiation monitoring and measurements. Topics are standardisation of environmental radiation measurements for ambient dose rate, dose mapping activity, investigation of foodstuff and drinking water, lending survey meters to citizens, etc. Based on the data and facts mainly gained by radiation monitoring, risk management and relating activity have been organised. 'Small consultation meetings in kindergartens', 'health consultation service for citizens', 'education meeting on radiation protection for teachers, medical staffs, local government staffs, and leaders of active volunteer parties' and 'decontamination activity', etc. are present key activities of the risk management and restoration around the Tokyo metropolitan area.

Gene expression differences in oocytes derived from adult and prepubertal Japanese Black cattle during in vitro maturation

The present study was carried out to compare the gene expression profiles in oocytes derived from adult and prepubertal Japanese Black cattle during in vitro maturation (IVM) using microarray gene chips (Bovine genome array containing 24,072 probe sets representing over 23,000 transcripts). Microarray experiments were conducted using total RNA isolated from immature [germinal vesicle (GV)] and in vitro matured [metaphase II, (MII)] oocytes derived from adult and prepubertal animals. A total of 333 (1.4%) and 549 (2.3%) genes were differentially expressed between prepubertal vs adult bovine GV and MII stages oocytes, respectively. Of these, 176 and 312 genes were up-regulated, while 157 and 237 were down-regulated in prepubertal when compared with adult GV and MII oocytes, respectively. It was also observed that 695 (2.9%) and 553 (2.3%) genes were differentially expressed between GV vs MII stage oocytes in the adult and prepubertal groups, respectively. Gene ontological classification of the differentially expressed genes revealed that up-regulated genes in adult oocytes were involved in signal transduction, transcriptional control and transport. Quantitative reverse transcription-PCR validated the expression profile of some selected transcripts and confirmed differences in the expression levels of transcripts between adult vs prepubertal groups in both GV and MII stages oocytes as identified by microarray data analysis. This study indicated for the first time that significant number of genes were differentially expressed (>2-fold, p < 0.01) between oocytes derived from adult and those from prepubertal Japanese Black cattle, and this difference increased during IVM.

Radiochemical study on the mechanism of target fragmentation of Cu, Nb, Pr and Au targets induced by 12C and 40Ar projectiles

A thick-target thick-catcher experiment was performed to measure the formation cross sections and recoil momenta of products from target fragmentation of Cu, Nb, Pr, and Au by using gamma-ray spectrometry. Bombardments of C ions (180, 290, and 400 MeV/u) and Ar ions (290 and 650 MeV/u) were performed at the HIMAC facility in Japan. The results were discussed in comparison with systematics of fragmentation and used to deduce the prefragments in fragmentation process of the measured systems.

Search for the decay of 229mTh by photon detection

A search for the isomeric transition of 229mTh at 3.5 eV was made by photon detection with a low-noise photomultiplier for samples prepared by a rapid chemical separation from the parent nuclide 233U by means of an anion exchange method. The photon emission caused by the disintegration of 229mTh was not observed for 229Th nitric acid solution samples. From the experimental results, the limits of the half-life of 229mTh as dissolved in HNO3 solution are discussed.

Transglutaminase down-regulates the dimerization of epidermal growth factor receptor in rat perivenous and periportal hepatocytes

OBJECTIVE

Recently, we found that transglutaminase 2 (TG2) might be involved in the difference in proliferative capacities between periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) through down-regulation of high-affinity epidermal growth factor receptor (EGFR). However, it is uncertain whether this high-affinity EGFR contributes to the hepatocyte growth signalling pathway. Here, we have investigated the influence of TG2 on EGF-induced EGFR dimerization and its phosphorylation, which are important steps in the hepatocyte proliferative/growth signalling pathway, in PPH and PVH.

MATERIALS AND METHODS

PPH and PVH were isolated using the digitonin/collagenase perfusion technique. Amounts of TG2, EGFR dimerization and its phosphorylation were determined by Western blot analysis.

RESULTS

Pretreatment with monodansylcadaverine, an inhibitor of TG2, greatly increased EGF-induced EGFR dimerization and its phosphorylation in PVH compared with PPH. Conversely, treatment with retinoic acid, an inducer of TG2, significantly decreased EGF-induced EGFR dimerization and its phosphorylation with a significant increase in TG2 expression and its catalysed products, isopeptide bonds, in both subpopulations. It was found that EGFR served as a substrate for TG2.

CONCLUSION

The present data showed good correlation with our previous data on EGF-induced DNA synthesis and EGFR-binding affinity to EGF. These results suggest that zonal difference in cell growth between PPH and PVH may be caused by down-regulation of EGFR dimerization and subsequent autophosphorylation through TG2-mediated cross-linking of EGFR.

Carbon ion radiotherapy for malignant melanoma of female genital organs

e16548

Background: Malignant melanoma of the female genital organs is a very rare tumor and resistant to conventional photon radiotherapy. We report six cases of female genital malignant melanoma those were well controlled locally by carbon ion radiotherapy (CIRT). Methods: Between November 2004 and October 2008, six patients with unresectable female genital malignant melanoma were treated with CIRT. Age of the patients ranged from 55 to 80 years (median; 69 years). Four patients had previously untreated locally invasive tumors and other two had locally recurrent tumors after surgery and adjuvant chemotherapy. The tumor located in the vagina (4 patients), both the cervix and the vagina (1 patient), or both the vagina and the vulva (1 patient). Two patients had inguinal lymph node metastasis and two had distant metastases at CIRT. All patients received a total dose of 57.6 gray equivalent (GyE) in 16 fractions over 4 weeks of CIRT. Three patients received chemotherapy using dacarbazine, ACNU, and vincristine after CIRT. Results: The follow-up durations after CIRT were from 9 to 20 months (median; 13 months). No patient developed severe acute toxicity during CIRT. No late toxicity of greater Grade 2 was experienced, while Grade 1 proctitis was observed in a patient. All tumors completely responded to CIRT. No patient developed in-field recurrence. The four patients without distant metastasis were alive with no evidence of disease for 9–20 months after CIRT. The two patients with distant metastases died from metastatic disease 13 and 18 months after CIRT, respectively. Conclusions: CIRT achieved favorable local tumor control without developing severe acute and late toxicity in the treatment of unresectable malignant melanoma of the female genital organs.

No significant financial relationships to disclose.

Prion removal by nanofiltration under different experimental conditions

Manufacturing processes used in the production of biopharmaceutical or biological products should be evaluated for their ability to remove potential contaminants, including TSE agents. In the present study, we have evaluated scrapie prion protein (PrP Sc) removal in the presence of different starting materials, using virus removal filters of different pore sizes. Following 75 nm filtration, PrP Sc was detected in the filtrate by Western blot (WB) analysis when a "super-sonicated" microsomal fraction derived from hamster adapted scrapie strain 263K (263K MF) was used as the spike material. In contrast, no PrP Sc was detected when an untreated 263K MF was used. By using spike materials prepared in a manner designed to optimize the particle size distribution within the preparation, only 15 nm filtration was shown to remove PrP Sc to below the limits of detection of the WB assays used under all the experimental conditions. However, infectious PrP Sc was recovered following 15 nm filtration under one experimental condition. The results obtained suggest that the nature of the spike preparation is an important factor in evaluating the ability of filters to remove prions, and that procedures designed to minimize the particle size distribution of the prion spike, such as the "super-sonication" or detergent treatments described herein, should be used for the preparation of the spike materials.

Transglutaminase differentially regulates growth signalling in rat perivenous and periportal hepatocytes

The influence of transglutaminase 2 (TG2) activity on the proliferative effect of epidermal growth factor (EGF) and on EGF receptor affinity in periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) has been investigated using a primary culture system. PPH and PVH subpopulations have been isolated using the digitonin/collagenase perfusion technique. DNA synthesis was assessed by [3H] thymidine incorporation into hepatocytes. The assay for binding of [125I] EGF to cultured hepatocytes was analysed by Scatchard plot analysis. Pretreatment with the TG2 inhibitor monodansylcadaverine (MDC) greatly increased EGF-induced DNA synthesis in both PPH and PVH. Furthermore, [125I] EGF binding studies in PVH treated with MDC indicated that high-affinity EGF receptor expression was markedly up-regulated, whereas in PPH, there was no significant effect. Treatment with retinoic acid (RA), an inducer of TG2 expression, significantly decreased EGF-induced DNA synthesis in both PPH and PVH. Binding studies in the presence of RA revealed that the high-affinity EGF receptor was down-regulated and completely absent in both PPH and PVH. These results suggest that TG2 was involved in the differential growth capacities of PPH and PVH through down-regulation of high-affinity EGF receptors.

A review of the action of tacrolimus (FK506) on experimental models of rheumatoid arthritis

Tacrolimus (FK506) is an immunosuppressive drug, widely used for organ transplantation and atopic dermatitis. Tacrolimus exerts its immunosuppressive effects primarily by interfering with the activation of T cells, via inhibition of calcineurin. Recent clinical studies have also demonstrated the efficacy of tacrolimus in the treatment of rheumatoid arthritis (RA), an autoimmune disease in which T cells play a pivotal role in pathogenesis. Inflammatory cytokines such as TNF-alpha, IL-1 beta, and IL-6 are involved in development of the disease. Recently, modes of action of tacrolimus on RA have been intensively studied in in vitro and animal arthritis models, demonstrating that tacrolimus exerts various novel actions as an anti-rheumatic drug. The pharmacological action of tacrolimus suggests that it has potential to specifically suppress the production of pathogenic inflammatory cytokines with a low frequency of infection, improve joint inflammation and bone/cartilage destruction, fully recover loss of functional status, exert rapid relief in arthritic pain, and promote osteogenic and chondrogenic differentiation. Here we review the action of tacrolimus on experimental models of RA, with a focus on our recent studies, and provide further insight into experimental models used for identifying efficacious anti-rheumatic drugs.

Comparison of anti-arthritic properties of leflunomide with methotrexate and FK506: effect on T cell activation-induced inflammatory cytokine production in vitro and rat adjuvant-induced arthritis

OBJECTIVE AND DESIGN

To examine the effect of leflunomide (LEF) on T cell activation-induced inflammatory cytokine production in human peripheral blood mononuclear cells (PBMC) and rat established adjuvant-induced arthritis (AIA), and compare these effects with methotrexate (MTX) and FK506 (tacrolimus), focusing on improvement of joint function in AIA.

METHODS

Human PBMC were cultured with immobilized anti-CD3/CD28 monoclonal antibody to produce tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6. The active metabolite of LEF was used in in vitro study. AIA was induced in female Lewis rats. Paw swelling and grip strength were measured as indicators of arthritis and joint function, respectively. Rats were therapeutically administered LEF (3.2-32 mg/kg) from days 15-24 by oral administration.

RESULTS

LEF inhibited anti-CD3/CD28 induced production of TNF-alpha, IL-1beta and IL-6, with IC50 values of 27, 21 and 21 microg/ml, respectively. LEF also suppressed mouse bone marrow cell MTT conversion, with an IC50 value of 15 microg/ml. LEF significantly inhibited paw swelling and loss of grip strength in established AIA at 10 and 32 mg/kg. The inhibition of paw swelling and grip strength loss by LEF was more potent than MTX. However, maximum recovery of grip strength loss by LEF (23.5%) was less potent compared to that with FK506 (57.8%).

CONCLUSIONS

LEF inhibited anti-CD3/CD28 induced inflammatory cytokine production in human PBMC at concentrations showing deleterious effects on bone marrow cell proliferation. LEF is superior to MXT in improving arthritis and joint function in established AIA, but is inferior to FK506 in recovering joint function, probably due to its anti-proliferative actions.

Nonfatal barium intravasation into the portal venous system during barium enema examination

We report a case of barium intravasation in a 66-year-old patient. Unenhanced computed tomography (CT) scan revealed barium and air emboli in portal veins and liver. We believe he survived because his liver prevented inflow of barium into the systemic circulation. To the best of our knowledge, this is the 23rd reported case of venous barium intravasation in the last 50 years. Because all 23 patients had bowel disease or diverticulitis, we conclude barium enema should be used cautiously in such patients.

Inflammatory cytokine levels in paw tissues during development of rat collagen-induced arthritis: Effect of FK506, an inhibitor of T cell activation

OBJECTIVE AND DESIGN

To characterize rat collagen-induced arthritis (CIA) on the basis of levels of inflammatory cytokines, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 in paw tissues, and further investigate the effect of FK506 (tacrolimus), a potent inhibitor of T cell activation, on cytokine levels.

METHODS

CIA was induced in female Lewis rats. The volume of hindpaws was measured before and after collagen immunization. TNF-alpha, IL-1beta and IL-6 levels in paw tissue extracts were determined by ELISA. Proteoglycan contents of cartilage in femoral heads was measured as an indication of cartilage destruction. To assess the effect of FK506 on inflammatory cytokine levels, rats were orally treated with 5 mg/kg of FK506 from days 14-21.

RESULTS

TNF-alpha a level in paw tissues did not significantly change compared to levels found before collagen immunization, throughout development of CIA. In contrast, IL-1beta and IL-6 levels in paw tissues significantly increased between day 14 and day 28 after collagen imuninization, when the arthritis was at a developed stage. Therapeutic treatment with FK506 reduced the elevated level of IL-6, but not IL-1beta, in paw tissue. FK506 treatment was effective in suppressing paw swelling and also recovering the loss of proteoglycan contents in the cartilage.

CONCLUSIONS

Levels of IL-1beta and IL-6, but not TNF-alpha , in paw tissue were upregulated in association with the development of arthritis in rat CIA. These results suggest that IL-1beta and IL-6, rather than TNF-alpha , may play important roles at local inflammatory sites in producing joint destruction in rat CIA. FK506 may improve arthritis in established stages of CIA, by reducing the elevated level of IL-6.