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Graphical abstract, Highlights • Temperature-responsive copolymer was synthesized using ultrasound. • The responsive temperature of the copolymer was controlled by reaction conditions. • Time course of the molar fraction of poly(N-isopropylacrylamide) was measured. • Lower critical solution temperature (LCST) increased with ultrasonic irradiation time. • LCST can be controlled by ultrasonic irradiation condition., Poly(N-isopropylacrylamide-co-2-hydroxyethyl methacrylate) (poly(NIPAM-co-HEMA)) is a temperature-responsive copolymer that is expected to be applicable as an advanced functional polymeric material in various fields. In this study, a novel method was developed to control the responsive temperature of poly(NIPAM-co-HEMA) using an ultrasonic polymerization technique. Initially, the behavior of the reaction was investigated using NIPAM and HEMA monomers under ultrasonic irradiation. A high ultrasonic power was found to produce a high reaction rate and low number average molecular weight of the copolymer. The polydispersity of the synthesized copolymer was approximately 1.5 for all ultrasonic powers examined. In the early stage of the reaction, the molar fraction of NIPAM in the copolymer was lower than the initial molar fraction of the monomers. It was concluded that ultrasonic irradiation affected the initiation reaction and polymer degradation, but did not affect the propagation reaction. Furthermore, the effect of the ultrasonic irradiation conditions on the temperature responsiveness of the copolymer was investigated. The lower critical solution temperature (LCST) of the copolymer was found to increase with increasing ultrasonic irradiation time. In addition, in the early stages of the reaction, the measured values of the LCST were higher than the estimated values using copolymer composition. This can be attributed to some parts of the copolymer chain possessing a higher NIPAM fraction than the overall fraction due to different reactivities of the monomers and terminated radicals. This hypothesis was indirectly verified by the synthesis of a block copolymer from the PNIPAM homopolymer and HEMA monomer.

In this presentation, we discuss noise floor comparisons of an optical displacement measuring interferometer between air and vacuum environments. A heterodyne interferometer and its phasemeter, with the resolution of 10-6 radian, implemented in a field programmable gate array (FPGA) are utilized for the comparison. A heterodyne laser source consists of a frequency stabilized He-Ne laser and two acoustic optic modulators (AOMs). The interferometer optics and a piezoelectric (PZT) flexure stage which drives the moving retroreflector of the interferometer are placed in a vacuum chamber. In the vacuum environment at 3 mPa, the noise floor of 1 pm/OHz or less is attained in the frequency range of 0.01 ~ 100 Hz.

The wide band gap (WBG) semiconductors such as Gallium Nitride (GaN) and Silicon Carbide (SiC) have characteristics of the low on-resistance and the high-speed switching for Si semiconductor. This paper proposes the Integrated Servomotor that integrates an AC motor with an amplifier miniaturized by adopting GaN power devices. Experimental results show the usefulness of GaN power devices in motor drive systems and the effect of the Integrated Servomotor on drive systems.

A new demodulation method for sinusoidal frequency/phase modulation (SFM/SPM) interferometers using an artificial harmonic series signal and a phase-locked loop (PLL) is proposed in the paper. Utilizing a laser diode (LD) as the light source and an electric optic modulator (EOM), frequency/phase modulations of the LD light can be achieved by modulating the LD injection current or the driving voltage to the EOM. The SFM/SPM interference signals for the displacement measurement has have the form of cos(msinωmt+θ), where m, ωm and φ are a modulation index, a modulation frequency and a phase change due to optical path movement, respectively. Therefore, the SFM/SPM interference signals is composed by a series of harmonics of the modulation frequency. The two adjacent (2k and 2k+1: k is integer) harmonics include the displacement information. By using the two harmonics, a Lissajous diagram can be drawn to obtain the displacements. In the conventional way, the two harmonics can be demodulated by two lock-in amplifiers. In this paper, we propose new demodulation method for SFM/SPM interferometers using an artificial hormonic series signal and the PLL, which are installed in field programable gate array (FPGA), to obtain sub-picometer (μrad) resolution. An artificial hormonic signals with the form of sin(msinωmt+θ) can be made virtually by the FPGA, where θ is the target phase controlled by the PLL. The output signal from the interferometer will be firstly digitized by the FPGA, and the digitized output signal and the artificial harmonic series signal are multiplied by a mixer, then the mixer output signal is inserted to a low pass filter (LPF). Then the LPF output signal should be -sin(φ-θ)~-(φ-θ) (if (φ-θ) is sufficiently small). In the system, modulation index should be fixed to some value. To set the LPF output signal (-(φ-θ)) to null, the target phase θ of the virtual artificial harmonic signal is controlled by the PLL. In the paper, we discuss the principle, experimental system and results.

In this paper, we present 10-pm-order mechanical displacement measurements using heterodyne interferometry. The measuring system includes a single-path heterodyne interferometer and a phase meter based on a phase-locked loop (PLL). It is not easy to measure a mechanical displacement of 10 pm or less owing to electronics and environmental noises in the interferometer. To solve this problem, the improvement of the noise floor is required for the phase meter. A PLL algorithm, which is programmed on a field-programmable gate array module, is used for efficient noise reduction of the phase meter. The interferometer combined with a stiff piezoelectric flexure stage is placed in a vacuum chamber. The measurement comparisons and the noise floor evaluations are performed between air and vacuum to evaluate effects from their environments. The interferometer has two spatially separated beams with different frequencies and two balanced optical arms. The measurement results demonstrate that the system combined with the above components is capable of measuring mechanical displacements of 11 pm in air and vacuum. A noise floor of 0.2 pm/ H z between 50 Hz and 100 Hz can be obtained in vacuum. In this paper, the setup of the interferometer, the signal processing of the PLL, experiments, and results are discussed.

In this paper, we discuss 20-picometer-order mechanical step displacement measurements using a heterodyne interferometer with a phase-locked loop (PLL) and two piezoelectric (PZT) driving flexure-stages. First, the phase meter for heterodyne interferometry using one simple digital PLL is developed. Two inputs and one output of the single PLL are the reference and measurement signals of the heterodyne interferometer and the phase shift due to the movement of the target mirror, respectively. The PLL includes an active phase shifter, a mixer (multiplier), a low-pass filter combined with an averaging operation, and an integrator. In electronics evaluation of the PLL, the PLL shows a phase resolution of 174 μrad with 4.2 μrad noise (standard deviation) and a phase noise floor of 3 μrad/√Hz above 0.2 Hz with an output sampling rate of 200 Hz. Using the single PLL, a four-pass normal commercial heterodyne interferometer, and high-stiff-parallel spring stage driven by PZT actuator, we demonstrate the actuations and measurements of mechanical step displacements of 19 pm (1.5 mrad) and a displacement noise floor of 1.1 pm/√Hz (90 μrad/√Hz) above 1 Hz in normal air. In the paper, the principle, instrumentation, and experimental results are discussed.

Long-term stock decline in the Japanese eel (Anguilla japonica) is a serious issue. To reduce natural resource utilization in Japan, artificial hormonal induction of maturation and fertilization in the Japanese eel has been intensively studied. Recent experiment on feminized (by feeding a commercial diet containing estradiol-17β for first half year) cultured female eels have shown ovulation problems, which is seldom observed in captured wild female eels. Therefore, the aim of this study is to try to investigate causes of ovulation problem frequently seen in cultured female eels by comparative trans-omics analyses. The omics data showed low growth hormone and luteinizing hormone transcription levels in the brain and low sex hormone-binding globulin transcription levels in the liver of the cultured female eels. In addition, it was found that high accumulation of glucose-6-phosphate and, maltose in the liver of the cultured female eel. It was also found that docosahexaenoic (DHA) acid, eicosapentaenoic acid (EPA) and arachidonic acid (ARA) ratios in cultured female eels were quite different from wild female eels. The data suggested that ovulation problem in cultured female eels was possibly resulted from prolonged intake of a high-carbohydrate diet and/or suboptimal DHA/EPA/ARA ratios in a diet.

As nanotechnology have been developed rapidly, it is strongly needed to measure a displacement accurately and precisely. A sinusoidal frequency modulation (SFM) and a sinusoidal phase modulation (SPM) applied interferometers could be good candidates. In the SFM, a frequency of a light source is modulated sinusoidal way. In the SPM, a phase is modulated. Characteristics of these interferometers are defined by a modulation index. The modulation index is a function of both a frequency excursion and an initial optical path difference in the SFM, and is an amplitude of phase in the SPM. For displacement measurement, the displacement is obtained by a phase of an interference signal. A phase determination method using a phase-locked loop (PLL) is reported and a few pico-meters resolution is achieved for displacement measurement with a restriction of a specific modulation index. For precise and high resolution interferometer, a stabilizing the frequency of the light source is necessary. Because the modulation index is an essential parameter in the frequency stabilization, performing phase determination with the PLL in the arbitral modulation index must be developed. The nonlinear relationship between the phase and the displacement is a problem in arbitral modulation index. We have proposed a PLL for arbitral modulation index which successively changes the relationship from the nonlinear to the linear. PC-based calculations with a theoretical and an actual interference signals have been conducted to check the feasibility of proposed PLL. In this report, displacement measurements using PC-based calculation with actual interference signals are described.

Background This paper shows how to suppress residual amplitude modulation (RAM) appeared in a commercial electro-optic modulator (EOM) to improve an iodine-frequency-stabilized laser diode (LD) using frequency modulation spectroscopy (FMS). Since the RAM of an EOM is affected by the temperature of the EOM, the DC-offset applied to the EOM and the polarization of the incident beam, it should easily fluctuate with drifts in temperature, applied voltage, and polarization. The fluctuation of the RAM of the EOM, which might decrease the frequency stability of the iodine-frequency-stabilized LD, must be eliminated by some means. Methods In this paper, we present a theoretical analysis and experimental results to express the RAM error from the EOM in a LD frequency stabilization system near 633 nm using iodine-saturated absorption. A RAM compensation system, which actuates the temperature of the EOM and the DC-offset applied to the EOM, is constructed for the commercial EOM. Results Using the RAM compensation system, the RAM is reduced to 10− 4 order, and frequency stability of ~ 3.67 × 10− 11 for 1000 s is achieved for the LD. Conclusions The proposed method can be applied for normal frequency stabilizing LDs, which use a commercial EOM and a low modulation index with FMS.

In this paper, direct phase determination method which is based on the phase-locked loop technique and the null method is proposed for heterodyne-displacement-measuring interferometers. The requirement of the proposed method is to detect high-speed phase changes in the phase shift between two sinusoidal input signals, leading to measuring high-speed displacements in industrial applications. The method is estimated for two situations that include the use of (a) two pure sinusoidal signals from a function generator and (b) two interferometric signals from a heterodyne interferometer, which is integrated to an electro-optic modulator for phase modulation. The experimental results of the method provide the phase-variation-measuring speed with a modulation frequency of 20kHz in the 2.7MHz-input sinusoid. The principle, signal-processing program, experiments and results of the method are presented in the paper.

As market demand for energy conservation products are increasing, matrix converters need to be further improved in efficiency and downsizing. On the other hand, next generation power devices such as SiC, GaN, which are capable of high speed switching with low loss have recently gained attention. In particular, the bidirectional GaN device is constituted by connecting two devices in series on the same die, which has an advantage that the conduction loss and the mounting area can be reduced. Conventional matrix converter requires at least 18 devices, but if bi-directional GaN devices are used, they can be composed with only 9 devices, which is useful for high efficiency and downsizing by reducing the conduction loss of the matrix converter. Matrix converter chipset using bidirectional GaN devices has already been developed, but as far as the authors know, a three phase motor has not been driven. This paper introduces the prototype nine switches matrix converter using bi-directional GaN devices, which successfully drives a three phase motor.

In tilapia, growth during critical periods of the life cycle varies at different ages of development and is influenced by sexual maturation. The mechanisms controlling gametogenesis and how growth affects this process are poorly understood. This study indicates that tilapia exhibit a sexually dimorphic growth pattern in which males grow faster and bigger than females. During critical periods of development growth patterns of tilapia vary between males and females as they increase in age and sexual maturation. In this study interactions between growth and reproductive development were examined by monitoring and comparing growth rates and reproductive histology. Female growth rate peaked at the very early stages of reproductive development during the cortical alveolar stages and male growth rate peaked after complete sexual maturation during spermiogenesis. The accumulation of cortical alveoli in the oocyte in females and spermiogenesis in males was determined to be the critical developmental periods of tilapia effecting growth rates. Kathmandu University Journal of Science, Engineering and Technology Vol. 8, No. II, December, 2012, 57-65 DOI: http://dx.doi.org/10.3126/kuset.v8i2.7326

The conventional method of measuring the radial, axial and angular spindle motion is complicated and needs large spaces. Smaller instrument is better in terms of accurate and practical measurement. A method of measuring spindle error motion using a sinusoidal phase modulation and a concentric circle grating was described in the past. In the method, the concentric circle grating with fine pitch is attached to the spindle. Three optical sensors are fixed under grating and observe appropriate position of grating. The each optical sensor consists of a sinusoidal frequency modulated semiconductor laser as the light source, and two interferometers. One interferometer measures an axial spindle motion by detecting the interference fringe between reflected beam from fixed mirror and 0th-order diffracted beam. Another interferometer measures a radial spindle motion by detecting the interference fringe between ±2nd-order diffracted beams. With these optical sensor, 3 axial and 3 radial displacement of grating can be measured. From these measured displacements, axial, radial and angular spindle motion is calculated concurrently. In the previous experiment, concurrent measurement of the one axial and one radial spindle displacement at 4rpm was described. In this paper, the sinusoidal frequency modulation realized by modulating injection current is used instead of the sinusoidal phase modulation, which contributes simplicity of the instrument. Furthermore, concurrent measurement of the 5 axis (1 axial, 2 radial and 2 angular displacements) spindle motion at 4000rpm may be described.

The matrix converter is an AC-to-AC direct power conversion system that can generate variable voltage variable frequency output. There is a topology of Matrix converter having sinusoidal waveforms using output LC filter. It enabled that to provide lower EMI, lower common-mode current, and lower shaft voltage. However, there are some problems that filter size become bulky because of the restriction of switching speed using conventional power module, Silicon IGBT. Downsizing of input-output filter can be realized by employing SiC power devices since they are associated with low losses and can be operated at high frequency. In this paper, the use of SiC power devices in matrix converters is studied and its effect in reducing the size of the input and output filter is verified. A prototype was built for evaluations and the results are presented.

The prevalence, clinical associations and pathogenic role of newly identified autoantibodies to the erythropoietin receptor (EPOR) in patients with anaemia were investigated. Sera from 203 patients with immune-related or chronic kidney diseases were screened for anti-EPOR antibodies by enzyme-linked immunosorbent assay, and antibody specificity was evaluated by immunoprecipitating EPOR from AS-E2 cells using purified immunoglobulin (Ig) fractions. In addition, the pathogenic role of anti-EPOR antibodies was determined by examining their inhibitory effects on AS-E2 cell proliferation. Clinical findings were compared between patients with and without anti-EPOR antibodies, in all patients and those with systemic lupus erythematosus (SLE). Serum anti-EPOR antibodies were detected in 52 patients. Purified IgG or IgM fractions from anti-EPOR antibody-positive sera immunoprecipitated EPOR and inhibited the EPO-dependent proliferation of AS-E2 cells in a dose-dependent manner. Anti-EPOR antibodies were associated with low haemoglobin concentrations and reticulocytopenia in all patients enrolled and those with SLE. Further, there was a negative correlation between the levels of anti-EPOR antibodies and the number of bone marrow erythroblasts in patients who underwent bone marrow examinations. These findings suggest that EPOR autoantibodies are present in a subset of patients with anaemia and that impaired erythropoiesis can be mediated by anti-EPOR antibodies, which functionally neutralize EPO activity.

It has been demonstrated that taurine has various physiological functions in the body. We demonstrated that taurine is abundant in the serum, liver, muscle and testis of the Japanese eel (Anguilla japonica). In the eel testis, taurine is found mainly in spermatogonia and is weakly expressed also in the Sertoli cells. We have further found in the eel testis that taurine is actively accumulated via the sodium/chloride-dependent taurine transporter (TauT; SLC6A6), which is expressed in germ cells. In our current study, the effects of taurine on the anti-oxidant response were examined. Taurine was found to promote the total superoxide dismutase (SOD) activity in the testis. Moreover, our results indicate that taurine does not affect the mRNA levels of copper-zinc (Cu/Zn) SOD or manganese SOD, but promotes the translation of Cu/Zn SOD. Overall, our present data suggest that taurine may modulate Cu/Zn SOD at the translational level and thereby may play an important role in the protection of germ cells from oxidative stress.

In teleost fish, the progestin 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) is an essential component of the spermatogenesis pathway. In a series of investigations on the mechanisms underlying progestin-stimulated spermatogenesis, we have found that DHP up-regulates the expression of cysteine dioxygenase1 (CDO1) in the Japanese eel testis. CDO1 is one of the enzymes involved in the taurine biosynthesis pathway. To evaluate whether taurine is synthesized in the eel testis, cysteine sulfinate decarboxylase (CSD), another enzyme involved in taurine synthesis, was isolated from this species. RT-PCR and in vitro eel testicular culture revealed that although CSD was also expressed in eel testis, neither DHP nor other sex steroids affect CSD mRNA expression in a similar manner to CDO1. Using an in vitro eel testicular culture system, we further investigated the effects of DHP on taurine synthesis in the eel testis. HPLC analysis showed that DHP treatment significantly increases the taurine levels in the eel testis. These results suggest that DHP promotes taurine synthesis via the up-regulation of CDO1 mRNA expression during eel spermatogenesis. Furthermore, we observed from our analysis that although taurine does not induce complete spermatogenesis, it promotes spermatogonial DNA synthesis and the expression of Spo11, a meiosis-specific marker. These data thus suggest that taurine augments the effects of sex steroids in the promotion of spermatogonial proliferation and/or meiosis and hence that taurine plays important roles in spermatogenesis.

We propose a sinusoidal phase modulation method to achieve both the frequency stabilization of an external-cavity laser diode (ECLD) to an 127I2 saturated absorption transition near 633 nm and displacement measurement using a Mach–Zehnder interferometer. First, the frequency of the ECLD is stabilized to the b21 hyperfine component of the P(33) 6-3 transition of 127I2 by combining sinusoidal phase modulation by an electro-optic modulator and frequency modulation spectroscopy by chopping the pump beam using an acousto-optic modulator. Even though a small modulation index of m = 3.768 rad is utilized, a relative frequency stability of 10−11 order is obtained over a sampling time of 400 s. Secondly, the frequency-stabilized ECLD is applied as a light source to a Mach–Zehnder interferometer. From the two consecutive modulation harmonics (second and third orders) involved in the interferometer signal, the displacement of the moving mirror is determined for four optical path differences (L0 = 100, 200, 500, and 1000 mm). The measured modulation indexes for the four optical path differences coincide with the designated value (3.768 rad) within 0.5%. Compared with the sinusoidal frequency modulation Michelson interferometer (Vu et al 2016 Meas. Sci. Technol. 27 105201) which was demonstrated by some of the same authors of this paper, the phase modulation Mach–Zhender interferometer could fix the modulation index to a constant value for the four optical path differences. In this report, we discuss the measurement principle, experimental system, and results.

Overproduction of hepcidin by interleukin-6 (IL-6) is considered to be the main factor responsible for the development of anemia in inflammatory conditions. Since oncostatin M (OSM), a member of the IL-6 family, plays an important role in immune and inflammatory responses, we assessed the effect of OSM on hepcidin expression, as well as that of leukemia inhibitory factor (LIF), another member of the IL-6 family. We found that hepcidin expression was markedly induced by OSM and LIF in a time- and dose-dependent manner in hepatoma cell lines, and this expression was induced independent of IL-6/IL-6 receptor signaling. Luciferase assay revealed that OSM and LIF stimulated a -1.3-kb hepcidin promoter. This effect was markedly reduced when the signal transducer and activator of transcription (STAT) site of the promoter was mutated, and was almost completely abolished in the presence of AG-490, a Janus kinase (JAK) inhibitor. Hence, the JAK/STAT pathway plays a major role in OSM- and LIF-induced activation of the hepcidin promoter. In conclusion, we demonstrated that OSM and LIF can induce hepcidin expression mainly through the JAK/STAT pathways. Further studies are warranted to evaluate the clinical significance of OSM and LIF in the development of anemia in various inflammatory diseases.

Hepcidin, a key iron-regulator secreted from the liver, consists of 25 amino acids (hepcidin-25), blocks iron release from macrophages via internalization and degradation of cellular iron exporter ferroportin, and restrains the use of iron in organs. Hepcidin mRNA and protein are also expressed in the human heart. A short form of hepcidin that lacks 5 amino-acid residues in the N-terminus (hepcidin-20) has been found in human serum, although its physiological role is unknown. Here, we successfully measured the serum levels of hepcidin-25 and hepcidin-20 in 12 patients with acute myocardial infarction (AMI) using surface-enhanced laser desorption ionization time of flight mass spectrometry. Among the selected 10 patients, whose blood samples were taken within 4 hours after a heart attack, all the patients showed elevated serum levels of hepcidin-20 [between 31.7 and 285.1 arbitrary unit (AU); normal level < 9.3 AU], while 8 patients showed high levels of hepcidin-25 (9.3-271.4; normal < 25.5 AU). The hepcidin-20 level was decreased to nearly the normal level on day 7 (range of 2.9 to 12.5 AU) in the 12 patients, whereas the hepcidin-25 level remained high on day 7 in 8 patients. Furthermore, the elevated levels of hepcidin-25 and hepcidin-20 were not correlated with the serum levels of markers for inflammation, interleukin-6 and C-reactive protein, in the patients with AMI. In conclusion, the serum hepcidin-20 is transiently elevated in response to acute cardiac ischemia. Measurement of serum hepcidin-20, rather than hepcidin-25, is helpful for diagnosis of acute myocardial infarction.

This research attempts to establish a method to measure 11 kinds of oxygenated volatile organic compound (OVOC) in ambient air by using the canister collection-gas chromatography/mass spectrometry (GC/MS) method. Since several compounds such as acetone exhibited high blank concentrations due to their laboratory use, stringent quality control was conducted for the VOC-free added water and the VOC-free nitrogen gas. In order to prevent the decline of recovery rates due to lack of sufficient relative humidity, it is necessary to add VOC-free water when pressurizing and diluting the air samples. Thus, all the target compounds in ambient air were obtained from the canisters at high recovery rates without significant contamination. Furthermore, the canister collection-GC/MS method makes it possible to apply simultaneous air monitoring of OVOCs as well as volatile hazardous air pollutants without additional sampling.

In fish spermatogenesis, the main action of progestins is generally regarded as the induction of sperm maturation. Our previous in vitro study demonstrated that a progestin, 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP), induced the initiation of meiosis in spermatogenesis in the Japanese eel (Anguilla japonica). In the present study, to elucidate the molecular mechanisms underlying the action of DHP, we attempted to clone cDNAs encoding genes whose expression was induced by DHP in eel testis, using cDNA subtraction. One of the cDNAs we isolated encodes eel 11beta-hydroxysteroid dehydrogenase short form (e11beta-HSDsf), and Northern blot and RT-PCR analysis showed that transcripts of e11beta-HSDsf in testis were induced by DHP. The recombinant e11beta-HSDsf had 11beta-dehydrogenase activity, metabolizing cortisol to cortisone, and 11beta-hydroxytestosterone to 11-ketotestosterone (11-KT). In vitro experiments revealed that eel immature testis had 11beta-dehydrogenase activity, and DHP treatment enhanced the activity. To understand the role of 11beta-HSD in spermatogenesis, we examined the direct effects of cortisol on eel spermatogenesis using an organ culture system. Cortisol induced DNA replication in spermatogonia and enhanced the spermatogonial proliferation induced by 11-KT. However, excess cortisol inhibited proliferation. In addition, 11-KT production was induced in testicular fragments incubated with cortisol. These results suggest that optimal levels of cortisol induced spermatogonial mitosis by increasing 11-KT production. Furthermore, two possible roles of DHP on spermatogenesis, via the up-regulation of 11beta-HSD expression, are suggested: positive feedback control of 11-KT production and the modulation of cortisol levels to protect testes from excess circulating cortisol.

Objectives Late treatment with erythropoietin (EPO), as well as the administration before the onset of or during the acute stage of myocardial infarction (MI), has recently been shown to mitigate post-MI heart failure. We investigated the mechanisms, including the downstream signaling pathways, for the beneficial effect of late treatment with EPO on chronic post-MI heart failure. Methods and results EPO (1500 U/kg, twice a week) was administered to mice beginning 6 weeks after induction of large MI. The EPO treatment for 4 weeks diminished left ventricular dilatation and improved function. It significantly reduced inflammatory cell infiltration and fibrosis, and increased vascular density in noninfarcted areas. The elevated levels of the inflammatory cytokines interleukin (IL)-1β, IL-6, tumor necrosis factor-α and transforming growth factor-β1 seen in the failing hearts were returned nearly to control levels by EPO treatment. Oxidative damage in surviving cardiomyocytes was also significantly attenuated by EPO. Expression of EPO receptor was upregulated in failing hearts, and EPO treatment led to myocardial activation of signal transducer and activator of transcription-3 (Stat3), Stat5, and Akt. These in vivo effects of EPO were confirmed in vitro in experiments that showed the anti-inflammatory and anti-oxidant effects of EPO to be mediated via Stat and Akt activation. Finally, the beneficial effects of EPO were found to persist for 4 weeks after discontinuing treatment. Conclusions It thus appears that Stat-mediated reduction of inflammation and cytokine production and Akt-mediated attenuation of oxidative stress accompany the beneficial effects of late treatment with EPO on chronic post-MI heart failure.

Stem cells are thought to inhabit in a unique microenvironment, known as "niche," in which they undergo asymmetric cell divisions that results in reproducing both stem cells and progenies to maintain various tissues throughout life. The cells of osteoblastic lineage have been identified as a key participant in regulating the number of hematopoietic stem cells (HSCs). HSCs receive their regulatory messages from the microenvironment in the bone marrow. This would account for a reason why the localization of hematopoiesis is usually restricted in the bone marrow. To clarify the above possibility we employed a cell implantation-based strategy with a unique osteoblast cell line (KUSA-A1) derived from a C3H/He mouse. The implantation of KUSA-A 1 cells resulted in the generation of ectopic bones in the subcutaneous tissues of the athymic BALB/c nu/nu mice. Subsequently the mice obtained a greater amount of the bone marrow than normal mice, and they showed an increased number of HSCs. These results indicate that the newly generated osteoblasts-derived ectopic bones are responsible for the increase in the number of the HSC population. Furthermore, the increased number of HSCs directly correlates with both the magnitude of dynamic osteogenic process and the size of the newly generated bone or "niche."

本研究では，嗅覚閾値の測定に与える下降法と上昇法の違いの影響を検討した．まず，下降法により測定される閾値（消臭点）と上昇法により測定される閾値（着臭点）との差異を検討するため，パネル選定用基準臭（イソ吉草酸，スカトール，メチルシクロペンテノロン）を用いて検討した．5-2法により下降法と上昇法で9人の被験者について閾値を測定した結果，両者にはほとんど差がなかった．次に，三点比較式臭袋法（下降法）と動的オルファクトメーター法（上昇法）の閾値の求め方の違いの影響を検討するため，臭袋法の測定条件を変えて実験を行ない検討した．12人の被験者について，n-ブタノールとオフセット輪転印刷臭の嗅覚閾値を測定した結果，それぞれの手法の閾値の求め方の違いにより，臭気指数換算で5程度オルファクトメーター法のほうが低い値となった．

Transgenic rats expressing the env-pX gene of human T cell leukemia virus type-I under the control of the viral long terminal repeat promoter (env-pX rats) developed systemic autoimmune diseases. Prior to disease manifestation, the immunosuppressive function of CD25(+)CD4(+) T (T-reg) cells was impaired in these rats. Since T cell differentiation appeared to be disordered in env-pX rats, we assumed that the impairment of T-reg cells might be caused by an abortive differentiation in the thymus. However, reciprocal bone marrow transfers between env-pX and wild-type rats revealed that direct effects of the transgene unrelated to the thymus framework induced the abnormality of T-reg cells. To identify molecular changes, comparative analyses were done between env-pX and wild-type T-reg cells. Expression of the Foxp3 gene and cell-surface markers supported a naive phenotype for env-pX T-reg cells. Array analyses of gene expression showed some interesting profiles, e.g. up-regulation of genes associated with the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways in env-pX T-reg cells. Additionally, expression of the suppressor of cytokine signaling (SOCS) family genes, which inhibit the JAK/STAT signals, was extremely low in env-pX T-reg cells. These findings suggest that the transgene may mediate the down-regulation of the SOCS family genes and that subsequent excess signals through the JAK/STAT pathways may result in the loss of function of env-pX T-reg cells. We suggest that investigation of the pathology of T-reg cells in our autoimmune-prone rat model may aid in understanding the roles of T-reg cells in human autoimmune diseases.

Recently, we developed a kidney-targeted gene transfer technique, in which naked DNA was injected into the renal vein while the renal vein and artery were clamped. Kidney-targeted DNA transfer with only the renal vein clamped is an important modification that may permit less invasive catheter-based gene transfer in future clinical applications. The preparation of PCR-amplified DNA fragments is less time-consuming than that of naked plasmid DNA. We examined rat erythropoietin (Epo) plasmid, pCAGGS-Epo, or PCR-amplified DNA fragment, fCAGGS-Epo, transfer into the rat kidney with only the renal vein clamped. The Epo level peaked at week 3 and then was sustained for 24 weeks, which resulted in significant erythropoiesis. This modified technique, allowing long-term expression of both PCR-amplified DNA fragments and naked plasmid DNA, could potentially be used for catheter-based gene transfer in humans, and could help determine the physiological functions of putative genes.

Solid ultra-cold neutron detectors consisting of a neutron converter layer and a silicon pin-diode were tested at Institute Laue Langevin. Two kinds of converter, LiF and LiOH, were used, and their critical velocities covered the range from 0.8 to 5.0 m / s by adjusting the isotopic fraction of 6 Li in Li. All tested detectors measured the UCN below their critical velocities down to 1.5 m / s without a clear cutoff feature at their critical velocities. It is an abnormal absorption of UCN. It was also observed that the detector efficiencies of all tested detectors approach together in the UCN region, 4– 6 m / s , in spite of the variety of critical velocity and thickness of converters.

Erythropoietin (Epo) and its receptor (EpoR) are indispensable to erythropoiesis. Although roles besides angiogenesis, such as neuroprotection and heart development, have been reported for the Epo-EpoR system, the precise contribution of Epo-EpoR to these nonhematopoietic tissues requires clarification. Exploiting aGATA-1 minigene cassette with hematopoietic regulatory domains, we established 2 lines of transgene-rescued EpoR-null mutant mice expressing EpoR exclusively in the hematopoietic lineage. Surprisingly, despite the lack of EpoR expression in nonhematopoietic tissues, these mice develop normally and are fertile. As such, we could exploit them for analyzing the roles of the Epo-EpoR system in adult hematopoiesis and in nonhematopoietic tissues. These rescued lines showed a differential level of EpoR expression in erythroid cells; one expressed approximately 40%, and the other expressed 120% of the wild-type EpoR level. A colony formation assay showed that erythroid progenitors in the 2 mutant lines exhibit distinct sensitivity to Epo. The circulating Epo level was much higher in the transgenic line with a lower EpoR expression. In response to induced anemia, the plasma Epo concentrations increased in both lines. Notably, the timing of the peak of plasma Epo concentration was delayed in both lines of rescued mice compared with wild type, suggesting that, in wild-type mice, nonhematopoietic EpoR contributes to the regulation of plasma Epo concentration. We thus conclude that nonhematopoietic expression of EpoR is dispensable to normal mouse development and that the expression level of EpoR regulates erythropoiesis by controlling the sensitivity of erythroid progenitors to Epo.

Necrotizing arteritis mimicking polyarteritis nodosa occurred in transgenic rats carrying the env-pX gene of human T-cell leukemia virus type I. To investigate the pathogenesis of necrotizing arteritis in these rats (env-pX rats), adoptive transfers of spleen cells and bone marrow cells were done from env-pX rats before they developed arteritis to nontransgenic rats. Necrotizing arteritis occurred in lethally irradiated nontransgenic rats reconstituted by env-pX spleen cells, thus indicating that the env-pX transgene in affected vessels may not be essential for the development of arteritis. In contrast, arteritis was not induced in nontransgenic recipients by adoptive transfers of env-pX bone marrow cells, which suggested that T cells derived from the env-pX thymus may play a role in the development of arteritis. To clarify if the process of differentiation of T cells in the env-pX thymus is crucial to develop necrotizing arteritis, reciprocal exchange of thymus frameworks was done between env-pX and nontransgenic rats. Necrotizing arteritis occurred in nontransgenic rats with an env-pX thymus framework, whereas development of arteritis was suppressed in env-pX rats in which the thymus framework was replaced with a nontransgenic one. This collective evidence shows that the thymus is directly associated with the development of necrotizing arteritis in env-pX rats.

Human T cell leukemia virus type I (HTLV-I) env-pX transgenic rats (env-pX rats) develop chronic destructive arthritis resembling rheumatoid arthritis in humans. Immunological characteristics were compared with those of collagen-induced arthritis (CIA). Rheumatoid factor was present in some env-pX rats regardless of the development of arthritis, but not in nontransgenic rats with CIA. All rats with CIA produced anti-type II collagen (IIC) antibody, but never so in env-pX rats with naturally occurring arthritis. Although expansions of oligoclonal T cells were evident in the affected joints, no particular clone was shown to infiltrate into the arthritic lesions in env-pX rats. In contrast to CIA, in which clonal expansions of IIC-specific T cells are implicated, locally expanded T cell clones against various antigens of the joints may play pathogenetic roles in the arthritis seen in env-pX rats. However, complementarity-determining region 3 of the TCR Vbeta gene of T cells accumulating at the affected joints in env-pX rats contained the GGA amino acid sequence, which was reported to be a conserved motif in HTLV-I env-pX transgenic mice with arthritis. These findings suggest that common antigen(s) might be recognized by T cells accumulating at sites of arthritis in both transgenic rats and mice.

A 66-year-old Japanese man developed severe anemia and erythroid hypoplasia in bone marrow without any significant underlying disease. The results of an antiglobulin test were strongly positive, and serum erythropoietin (Epo) was high. The patient was diagnosed as having acquired pure red cell aplasia (PRCA) and was treated with steroids. Anemia was subsided by reticulocyte production in parallel with a decrease in the titer of antiglobulin test and the level of Epo. We studied the immunological mechanism directed against erythroid cells in vitro by using the patient's serum. In vitro analysis indicated the presence of an inhibitor of erythroid precursors at onset, and its disappearance at remission, suggesting the presence of inhibitor against erythroid precursors.

Erythropoietin (Epo) is one of the main regulators of growth and differentiation of hematopoietic cells. In normal bone marrow cells, the amount of erythropoietin receptor (EpoR) was highest in the CD34+ CD38- subset, and decreased on lineage committed progenitor cells expressing CD38 antigens. Among the erythroid cells expressing GpA antigens, CD34-positive fractions expressed more EpoR than CD34-negative fractions. Although the amounts of EpoR of bone marrow cells from patients with refractory anemia (RA) were less than those of normal bone marrow cells in all phenotypes examined, there was no statistical significant difference. EpoR was detected on leukemia cells from 60% of acute myeloblastic leukemia (AML) cases and 29% of acute lymphoblastic leukemia (ALL) cases, and distributed widely among all FAB-subtypes. In spite of the presence of EpoR, in vitro proliferative response to Epo was not observed in a large proportion of AML. And there was no correlation between the amount of EpoR and the in vitro response to EPO. Patients with both EpoR expression and in vitro response to Epo had shorter remission duration than those without EpoR.

The replication fork temporarily stalls when encountering an obstacle on the DNA, and replication resumes after the barrier is removed. Simultaneously, activation of the replication checkpoint delays the progression of S phase and inhibits late origin firing. Camptothecin (CPT), a topoisomerase I (Top1) inhibitor, acts as a DNA replication barrier by inducing the covalent retention of Top1 on DNA. The Timeless-Tipin complex, a component of the replication fork machinery, plays a role in replication checkpoint activation and stabilization of the replication fork. However, the role of the Timeless-Tipin complex in overcoming the CPT-induced replication block remains elusive. Here, we generated viable TIPIN gene knock-out (KO) DT40 cells showing delayed S phase progression and increased cell death. TIPIN KO cells were hypersensitive to CPT. However, homologous recombination and replication checkpoint were activated normally, whereas DNA synthesis activity was markedly decreased in CPT-treated TIPIN KO cells. Proteasome-dependent degradation of chromatin-bound Top1 was induced in TIPIN KO cells upon CPT treatment, and pretreatment with aphidicolin, a DNA polymerase inhibitor, suppressed both CPT sensitivity and Top1 degradation. Taken together, our data indicate that replication forks formed without Tipin may collide at a high rate with Top1 retained on DNA by CPT treatment, leading to CPT hypersensitivity and Top1 degradation in TIPIN KO cells.

An experimental study was carried out for J/ψ production in a two-photon process using the VENUS detector at the TRISTAN e+e− collider. The study was based on 357 pb−1 data at an average e+e− center-of-mass energy of 58 GeV. No significant signal was observed, and the upper limit of the production cross section was obtained.

NG-monomethyl-l-arginine (L-NMMA) has been reported to be elevated in uremic patients. Based on the hypothesis that the pathogenesis of the anemia of renal disease might be due to the perturbation of transcription factors of the erythropoietin (Epo) gene by L-NMMA, the present study was designed to investigate the effect of L-NMMA on Epo gene expression through the GATA transcription factor. L-NMMA caused decreased levels of NO, cyclic guanosine monophosphate (cGMP), and Epo protein in Hep3B cells. L-NAME (analogue of L-NMMA) also inhibited Epo production in anemic mice. Transfection of the Epo promoter-luciferase gene into Hep3B cells revealed that L-NMMA inhibited the Epo promoter activity. However, L-NMMA did not inhibit the Epo promoter activity when mutated Epo promoter (GATA to TATA) was transfected, and L-NMMA did not affect the enhancer activity. Electrophoretic mobility shift assays demonstrated the stimulation of GATA binding activity by L-NMMA. However, L-NMMA had no effect on the binding activity of hepatic nuclear factor-4, COUP-TF1, hypoxia-inducing factor-1, or NF-κB. Furthermore, cGMP inhibited the L-NMMA–induced GATA binding activity. L-NMMA also increased GATA-2 messenger RNA expression. These results demonstrate that L-NMMA suppresses Epo gene expression by up-regulation of the GATA transcription factor and support the hypothesis that L-NMMA is one of the candidate substances that underlie the pathogenesis of renal anemia.

金沢大学医薬保健研究域医学系, A 42-year-old woman with systemic lupus erythematosus was admitted to our hospital because of severe anemia. Her bone marrow was almost normocellular and erythroblasts were nearly absent. Laboratory data showed elevated levels of lactate dehydrogenase and positive findings on Coombs' tests. On the basis of these findings, her anemia was diagnosed as the overlap of pure red cell aplasia with autoimmune hemolytic anemia. Radioimmunoprecipitation assay revealed that her serum was positive for anti-erythropoietin antibodies before therapy. Furthermore, the autoantibodies inhibited proliferation of an erythropoietin-dependent cell line in a dose-dependent manner. Immunosuppressive treatment improved the anemia accompanied with disappearance of the autoantibodies. © 2008 Wiley-Liss, Inc.

The charged-particle multiplicity is measured for b -quark and light-quark ( u , d , s ) events in e + e − annihilation at s =58 GeV. Two independent methods, lepton tagging and decay-length tagging, are applied to enrich b -quark events. These methods provide event samples having different concentrations of b -quark events. The mean charged multiplicity is measured to be 19.38±0.27±0.84 for b -quark events, and 15.91±0.04±0.70 for light-quark events. The results are compared with predictions of phenomenological and theoretical models.

The cross section of the γγ → p p reaction was measured at two-photon center-of-mass energy (Wγγ) between 2.2 and 3.3 GeV, using the two-photon process at an e+e− collider, TRISTAN. The Wγγ dependence of the cross section integrated over a c.m. angular region of | cos θ ∗ | is in good agreement with the previous measurements and the theoreticalv prediction based on diquark model in the high Wγγ region.