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TAL2 is a transcription factor required in the normal development of mouse brain. In a previous study, we demonstrated that the expression of Tal2 gene is induced by the complex of all-trans retinoic acid (atRA) and retinoic acid receptor α (RARα) in mouse embryonal carcinoma P19 cells. atRA is also known to be important in inducing P19 cells to differentiate into the neural lineage. Therefore, we believe that the function of TAL2 in neural differentiation may be clarified by utilizing P19 cells. As the atRA-RARα complex induced the expression of Tal2, we focused on the regulatory region that is involved in its transcription. The atRA-RARα complex occupies a characteristic retinoic acid response element (RARE) located in the promoter of target genes. Therefore, we searched for RARE on the mouse Tal2 and found that a RARE-like element was located in the intron. We also found that a TATA-box-like element was located in the 5'-region of Tal2. Involvement between transcriptional activity and the TATA-box-like element was confirmed in the luciferase assay, and TATA-box binding protein was bound to this element upstream of Tal2 in P19 cells. atRA signaling activated the transcription through the RARE-like element, and RARα was bound to this element on Tal2 in P19 cells. In addition, the interaction between these elements on Tal2 was shown in the chromatin immunoprecipitation assay. These results suggest that the transcription of Tal2 is coordinately mediated by two distal regulatory elements.

Cadmium is a transition metal that is classified as human carcinogen by the International Agency for Research on Cancer (IARC) with multiple target sites. Many studies using various model systems provide evidence of cadmium-induced malignancy formation in vivo or malignant cell transformation in vitro. Nonetheless, further studies are needed to completely understand the mechanisms of cadmium carcinogenicity. Our prior studies have utilized a rat liver epithelial cell line (TRL 1215) as a model for cadmium-induced malignant transformation. In the present study, we focused on the molecular mechanisms of this malignant transformation, especially with regard to hyper-invasiveness stimulated by cadmium transformation. By performing a series of biochemical analyses on cadmium transformed cells, it was determined that cadmium had significantly down-regulated the expression of apolipoprotein E (ApoE). ApoE was recently established as a suppressor of cell invasion. A key factor in the suppression of ApoE by cadmium appeared to be that the metal evoked a 5-aza-2'-deoxycytidine-sensitive hypermethylation of the regulatory region of ApoE, coupled with interference of the action of liver X receptor α (LXRα), a transcriptional regulator for ApoE. Furthermore, the expression of LXRα itself was suppressed by cadmium-mediated epigenetic modification. Re-expression of ApoE clearly abrogated the cell invasion stimulated by cadmium-induced malignant transformation. Together, the current results suggest that the cadmium-mediated enhanced cell invasion is linked to down-regulation of ApoE during malignant transformation these liver cells.

In a previous study, we showed that formylmethylflavin (FMF) can bind to cysteine. In this study, FMF was reacted with native peptides (CG and CKLVFF) containing an N-terminal cysteine. The formation of flavin-CG and flavin-CKLVFF was confirmed using HPLC and ESI-MS. Storage of flavin-CKLVFF in DMSO at −30 °C for 7 days resulted in no detectable deposition. In contrast, flavin-CKLVFF formed deposits when stored in water at −30 °C for 1 day, but no deposit was observed in the aqueous solution of flavin-CKLVFF after 7 days storage in the presence of 0.1% Triton X-100.

Guanine is the most easily oxidized among the four DNA bases, and some guanine-rich sequences can form quadruplex structures. In a previous study using 6-mer DNA d(TGGGGT), which is the shortest oligomer capable of forming quadruplex structures, we demonstrated that guanine oxidation products of quadruplex DNA differ from those of single-stranded DNA. Therefore, the hotooxidation products of double-stranded DNA (dsDNA) may also differ from that of quadruplex or single-stranded DNA, with the difference likely explaining the influence of DNA structures on guanine oxidation pathways. In this study, the guanine oxidation products of the dsDNA d(TGGGGT)/d(ACCCCA) were analyzed using HPLC and electrospray ionization-mass spectrometry (ESI-MS). As a result, the oxidation products in this dsDNA were identified as 2,5-diamino-4H-imidazol-4-one (Iz), 8-oxo-7,8-dihydroguanine (8oxoG), dehydroguanidinohydantoin (Ghox), and guanidinohydantoin (Gh). The major oxidation products in dsDNA were consistent with a combination of each major oxidation product observed in single-stranded and quadruplex DNA. We previously reported that the kinds of the oxidation products in single-stranded or quadruplex DNA depend on the ease of deprotonation of the guanine radical cation (G•+) at the N1 proton. Similarly, this mechanism was also involved in dsDNA. Deprotonation in dsDNA is easier than in quadruplex DNA and more difficult in single-stranded DNA, which can explain the formation of the four oxidation products in dsDNA.

Human alanine-serine-cysteine transporter 2 (ASCT2; SLC1A5) is a major transporter of the amino acid glutamine that is known to be overexpressed in certain malignant tumors. In this study, we generated specific monoclonal antibodies (MAbs) against ASCT2 by establishing an ASCT2-expressing Chinese hamster ovary cell line that was used to immunize mice and rats. The MAbs KM4008, KM4012, and KM4018 against ASCT2 were isolated through a cell-based screen; these specifically bound to ASCT2-positive cells, as determined by flow cytometry and immunoprecipitation. In addition, the antibodies suppressed glutamine-dependent growth of WiDr colorectal cancer cells. These results provide evidence supporting the use of MAbs against ASCT2 as an effective therapeutic strategy for cancer treatment.

The cardio-ankle vascular index (CAVI) has been proposed as a new noninvasive marker of arterial stiffness independent of blood pressure. Arterial stiffness is closely related to afterload, and elevated afterload aggravates heart failure. We hypothesized that CAVI is a potential marker of afterload in patients with heart failure. Thirty patients who were admitted because of acute heart failure were identified retrospectively from a review of clinical records. Plasma brain natriuretic peptide (BNP) levels, CAVI, cardiothoracic ratio (CTR), and echocardiographic parameters obtained during acute and chronic phases of heart failure were analyzed. Left ventricular ejection fraction (LVEF) increased significantly and CTR, BNP and CAVI decreased significantly after treatment of heart failure. A significant negative correlation was observed between the change in CAVI and change in LVEF in all subjects (r = -0.3272, P < 0.05). To examine the relationship between CAVI and LVEF, we divided the patients into two subgroups (∆CAVI < -0.5; CAVI decrease group, ∆CAVI ≥ -0.5; CAVI non-decrease group). CAVI was significantly improved after heart failure treatment only in the CAVI decrease group. LVEF decreased significantly in both groups, but the P value was smaller in the CAVI decrease group than in the CAVI non-decrease group. The change in LVEF correlated significantly with the change in CAVI in the CAVI decrease group (r = -0.4201, P < 0.05), whereas no significant correlation was found in the CAVI non-decrease group. CAVI correlates inversely with LVEF after heart failure treatment. Our results suggest that CAVI might partially reflect the afterload in patients with heart failure.

Masayo Suzuki,1 Mao Takahashi,1 Takuo Iizuka,1 Hitoshi Terada,2 Hirohumi Noike,1 Kohji Shirai3 1Cardiovascular Center, Internal Medicine, 2Department of Radiology, 3Department of Vascular Function, Sakura Hospital, Medical Center, Toho University, Sakura City, Chiba Prefecture, Japan Background: Familial hypercholesterolemia (FH) is associated with premature coronary arterial disease. We aimed to determine the incidence of coronary artery stenosis (CAS) in asymptomatic FH patients using coronary computed tomography angiography (CCTA). To investigate the association between CAS and atherosclerosis of carotid arteries, we performed ultrasonography to measure the mean intima-media thickness (IMT), maximum IMT, and plaque score. We also aimed to examine the significance of the cardio-ankle vascular index (CAVI) and its association with the incidence of CAS in asymptomatic FH patients. Patients and methods: We enrolled consecutively, 31 FH patients without symptoms of coronary artery disease. Based on the CCTA findings, we divided the patients into two groups, those with and without CAS, and compared various parameters and risk factors of the two groups. Results: Of 31 FH patients, seven patients (22.6%) had CAS. The proportion of male patients and mean low-density lipoprotein-cholesterol level were higher in patients with CAS than in those without CAS (P22.6% of the asymptomatic FH patients. Patients with CAS tended to have enhanced levels of carotid plaque markers, but no increase was noted in CAVI. FH patients should be continuously monitored using CCTA and ultrasonography. Keywords: CAVI, coronary artery stenosis, heterozygous familial hypercholesterolemia, CCTA, ultrasound evaluation of the carotid artery

Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder caused by a deficiency of alpha-galactosidase A. Approximately 50% of patients with AFD may have cardiac involvement. Gadolinium-enhanced cardiac magnetic resonance (CMR) is useful for the diagnosis of cardiac involvement of AFD by recognizing typical late gadolinium enhancement (LGE) patterns. We report a 48-year-old man with cardiac involvement in classical AFD, showing atypical distribution of the LGE at the mid-lateral wall of left ventricle, predominantly apical segments without basal involvement on gadolinium-enhanced CMR.

DNA is constantly exposed to endogenous and exogenous oxidative stresses. Damaged DNA can cause mutations, which may increase the risk of developing cancer and other diseases. G:C-C:G transversions are caused by various oxidative stresses. 2,2,4-Triamino-5(2H)-oxazolone (Oz), guanidinohydantoin (Gh)/iminoallantoin (Ia) and spiro-imino-dihydantoin (Sp) are known products of oxidative guanine damage. These damaged bases can base pair with guanine and cause G:C-C:G transversions. In this study, the stabilization energies of these bases paired with guanine were calculated in vacuo and in water. The calculated stabilization energies of the Ia:G base pairs were similar to that of the native C:G base pair, and both bases pairs have three hydrogen bonds. By contrast, the calculated stabilization energies of Gh:G, which form two hydrogen bonds, were lower than the Ia:G base pairs, suggesting that the stabilization energy depends on the number of hydrogen bonds. In addition, the Sp:G base pairs were less stable than the Ia:G base pairs. Furthermore, calculations showed that the Oz:G base pairs were less stable than the Ia:G, Gh:G and Sp:G base pairs, even though experimental results showed that incorporation of guanine opposite Oz is more efficient than that opposite Gh/Ia and Sp.

Tangier disease, characterized by low or absent high-density lipoprotein (HDL), is a rare hereditary lipid storage disorder associated with frequent, but not obligatory, severe premature atherosclerosis due to disturbed reverse cholesterol transport from tissues. The reasons for the heterogeneity in atherogenicity in certain dyslipidemias have not been fully elucidated. Here, using high-performance liquid chromatography with a gel filtration column (HPLC-GFC), we have studied the lipoprotein profile of a 17-year old male patient with Tangier disease who to date has not developed manifest coronary atherosclerosis. The patient was shown to be homozygous for a novel mutation (Leu1097Pro) in the central cytoplasmic region of ATP-binding cassette transporter A1 (ABCA1). Serum total and HDL-cholesterol levels were 59mg/dl and 2mg/dl, respectively. Lipoprotein electrophoretic analyses on agarose and polyacrylamide gels showed the presence of massively abnormal lipoproteins. Further analysis by HPLC-GFC identified significant amounts of lipoproteins in low-density lipoprotein (LDL) subfractions. The lipoprotein particles found in the peak subfraction were smaller than normal LDL, were rich in triglycerides, but poor in cholesterol and phospholipids. These findings in an adolescent Tangier patient suggest that patients in whom these triglyceride-rich, cholesterol- and phospholipid-poor LDL-type particles accumulate over time, would experience an increased propensity for developing atherosclerosis.

Introduction: Glutamine is the most abundant amino acid in blood, serving as a major biosynthetic substrate in nucleic acids and proteins. Recent studies have shown that glutamine contributes to cancer cell proliferation, invasion, and metastasis, so targeting the glutamine pathway is expected to be a feasible approach to cancer treatment. In cancer cells, the Na+-dependent neutral amino acid exchanger alanine-serine-cysteine (ASC) transporter 2 (ASCT2) plays a key role in the glutamine uptake. ASCT2 has been shown to be overexpressed in a variety of cancerous tissues, including gastric cancer. In this study, we established a defucosylated humanized anti-human ASCT2 monoclonal antibody, KM8094, that specifically binds to the natural configuration of an extracellular domain of ASCT2. We further evaluated the efficacy of KM8094 as a therapeutic agent for gastric cancer treatment using gastric cancer cell lines. Materials and Methods: Immunohistochemistry was conducted on tumor tissue specimens. The ASCT2 expression on tumor cell-surface was analyzed by flow cytometry using KM8094 and PE-conjugated anti-human IgG monoclonal antibody. The glutamine uptake in human gastric cancer cells (SNU-16) was examined using 14C-labeled glutamine. Cell growth was measured by a CellTiter-Glo Luminescent Cell Viability Assay after 72-h treatment with KM8094 or control IgG. The in vivo anti-tumor activity of KM8094 combined with docetaxel was examined using gastric cancer xenograft models. Results: In the immunohistochemical analysis, we observed the high expression of ASCT2 in human tumor tissues, including gastric cancer. To evaluate the inhibitory activity on the ASCT2 transporter function and tumor cell growth of KM8094, we performed a glutamine uptake assay using 14C-glutamine. As a result, KM8094 inhibited the 14C-glutamine uptake in SNU-16 gastric cancer cells expressing ASCT2. KM8094 also suppressed cell growth of multiple gastric cancer cell lines both in vitro and in vivo. These results suggested that KM8094 has therapeutic potential for gastric cancer by inhibiting ASCT2 transporter activity. Furthermore, in an SNU-16 gastric cancer xenograft model, combination therapy of KM8094 and docetaxel, a therapeutic drug for gastric cancer, showed a more potent antitumor effect than either agent alone. Conclusions: KM8094 may be a potential new therapeutic agent for gastric cancer expressing ASCT2, as it exhibited antitumor growth activities both in vitro and in vivo. Citation Format: Aya Sasakawa, Kenta Hosomi, Toshihiko Ishii, Hiroshi Ando, Masayo Suzuki, Minami Imaizumi, Jian Zou, Noriyuki Kasai, Kazuya Yamano, Kazuyasu Nakamura, Ryuichiro Nakai. The establishment and evaluation of anti-ASC amino acid transporter 2 (ASCT2) antibody as a novel therapeutic antibody for gastric cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B037.

AIM To investigate the effect of smoking and smoking cessation on cardio-ankle vascular index (CAVI). METHODS The subjects were 82 smokers (77 men, 64+/-10 years) and 20 non-smokers (18 men, 61+/-7 years). CAVI was measured every 3 months and CAVI severity was classified into 3 levels. Decreased, unchanged, and increased CAVI severity levels were coded as "improvement," "no change," and "exacerbation," respectively. Smoking status was coded as "success" for complete abstinence, "partial success" for a reduced number of cigarettes, and "failure" for an unchanging number of cigarettes. RESULTS Compared with non-smokers, smokers showed a higher CAVI (p

Claudin-4 (CLDN4) is a tetraspanin transmembrane protein of tight junction structure and is highly expressed in pancreatic and ovarian cancers. In this study, we aimed to generate an anti-Claudin-4 monoclonal antibody (mAb) and evaluate its antitumor efficacy in vitro and in vivo. To isolate specific mAb, we generated CLDN3, 4, 5, 6, and 9, expressing Chinese hamster ovary (CHO) cells, and then used them as positive and negative targets through cell-based screening. As a result, we succeeded in isolating KM3900 (IgG2a), which specifically bound to CLDN4, from BXSB mice immunized with pancreatic cancer cells. Immunoprecipitation and flow cytometry analysis revealed that KM3900 recognized the conformational structure and bound to extracellular loop 2 of CLDN4. Furthermore, binding of KM3900 was detected on CLDN4-expressing pancreatic and ovarian cancer cells, but not on negative cells. Next, we made the mouse-human chimeric IgG1 (KM3934) and evaluated its antitumor efficacy. KM3934 induced dose-dependent antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity in vitro, and significantly inhibited tumor growth in MCAS or CFPAC-1 xenograft SCID mice in vivo (P < 0.05). These results suggest that mAb therapy against CLDN4 is promising for pancreatic and ovarian cancers.

経胸壁ドプラ心エコー法による冠動脈の描出が可能となり，冠血流速波形の解析から冠循環の評価が行われるようになってきた．冠動脈遠位部は検出率が高く，その血流評価に対する多数の報告がなされているのに対して，冠動脈近位部を評価した報告は少ない．今回我々は，経胸壁ドプラ心エコー法により，冠動脈近位部狭窄の診断が可能であった不安定狭心症の2症例を経験したので報告する．症例1：79歳，男性．胸痛を主訴に入院．発作時の心電図では II ，III，aVF，V3‐6のST低下を認めた．経胸壁心エコー検査では，左室壁運動が心尖部で若干低下していたが左室駆出率は正常であった．大動脈弁レベルの短軸像で冠動脈近位部を直接描出したところ，左前下行枝近位部に加速血流を認め拡張期最高血流速度は104cm/秒と高速であった．冠動脈造影の結果，分節6に99%狭窄を認め，経胸壁心エコー検査で認められた狭窄部と一致していた．狭窄部にステントを留置し良好な拡張に成功した．術後の経胸壁心エコー検査では，冠動脈内の加速血流は消失し拡張期最高血流速度は40cm/秒と正常化した．症例2：59歳，男性．胸痛を主訴に入院．発作時の心電図で II ，III，aVFの陰性T波を認めた．経胸壁心エコー検査では，左室壁運動異常は認めなかった．大動脈弁レベルの短軸像で冠動脈近位部を直接描出したところ，右冠動脈近位部に加速血流を認め拡張期最高血流速度は108cm/秒と高速血流であった．冠動脈造影の結果，分節1に99%狭窄を認め，経胸壁心エコー検査で認められた狭窄部と一致していた．狭窄部にステントを留置し良好な拡張に成功した．術後の経胸壁心エコー検査では，冠動脈内の加速血流は消失し拡張期最高血流速度は26cm/秒と正常化した．非ST上昇型の不安定狭心症において，経胸壁ドプラ心エコー法により冠動脈近位部の狭窄病変を直接描出することが可能であった．本法は，冠動脈近位部狭窄の有無を心臓カテーテル検査前に予測する上で有用な検査法と考えられた．

著者人数: 20名, 資料番号: SA1000093000

Mutations induced by oxidative DNA damage can cause diseases such as cancer. In particular, G:C-T:A and G:C-C:G transversions are caused by oxidized guanine and have been observed in the p53 and K-ras genes. We focused on an oxidized form of guanine, 2,2,4-triamino-5(2H)-oxazolone (Oz), as a cause of G:C-C:G transversions based on our earlier elucidation that DNA polymerases (Pols) α, β, γ, ε, η, I, and IV incorporate dGTP opposite Oz. The nucleotide insertion and extension of Pols δ, ζ, ι, κ, and REV1, belonging to the B- and Y-families of DNA polymerases, were analyzed for the first time. Pol δ incorporated dGTP, in common with other replicative DNA polymerases. Pol ζ incorporated dGTP and dATP, and the efficiency of elongation up to full-length beyond Oz was almost the same as that beyond G. Although nucleotide incorporation by Pols ι or κ was also error-prone, they did not extend the primer. On the other hand, the polymerase REV1 predominantly incorporated dCTP opposite Oz more efficiently than opposite 8-oxo-7,8-dihydroguanine, guanidinohydantoin, or tetrahydrofuran. Here, we demonstrate that Pol ζ can efficiently replicate DNA containing Oz and that REV1 can prevent G:C-C:G transversions caused by Oz.

Human claudin-3 (CLDN3) is a tetraspanin transmembrane protein of tight junction structures and is known to be over-expressed in some malignant tumors. Although a specific monoclonal antibody (MAb) against the extracellular domains of CLDN3 would be a valuable tool, generation of such MAbs has been regarded as difficult using traditional hybridoma techniques, because of the conserved sequence homology of CLDN3s among various species. In addition, high sequence similarity is shared among claudin family members, and potential cross-reactivity of MAb should be evaluated carefully. To overcome these difficulties, we generated CLDN3-expressing Chinese hamster ovary and Sf9 cells to use an immunogens and performed cell-based screening to eliminate cross-reactive antibodies. As a result, we generated MAbs that recognized the extracellular loops of CLDN3 but not those of CLDN4, 5, 6, or 9. Further in vitro studies suggested that the isolated MAbs possessed the desired binding properties for the detection or targeting of CLDN3.

We have been developing an X-ray photoelectron tracking imager based on a glass capillary plate (CP) gas detector for cosmic X-ray polarimetry applications. The optical imaging system consists of a CP gas detector filled with a noble-gas mixture and a cooled CCD camera coupled to an optical lens system. The performance of the optical imaging CP gas detector as an X-ray polarimeter was investigated with highly polarized, well-monochromized, and well-collimated X-ray beams at the synchrotron radiation facilities in SPring-8 and KEK-PF. Owing to the fine imaging capability of the optical imaging CP gas detector, images of X-ray photoelectron tracks were clearly observed for the polarized X-rays. A modulation factor of 26% was obtained for a 15 keV polarized X-ray beam, for which the energy resolution was 13%. We report on the properties of the optical imaging CP gas detector as an X-ray polarimeter and describe the outlook on future developments on the basis of the measured characteristics and the results of Monte Carlo simulations.

TAL2 is a transcription factor required in the normal development of mouse brain. In a previous study, we demonstrated that the expression of Tal2 gene is induced by the complex of all-trans retinoic acid (atRA) and retinoic acid receptor α (RARα) in mouse embryonal carcinoma P19 cells. atRA is also known to be important in inducing P19 cells to differentiate into the neural lineage. Therefore, we believe that the function of TAL2 in neural differentiation may be clarified by utilizing P19 cells. As the atRA-RARα complex induced the expression of Tal2, we focused on the regulatory region that is involved in its transcription. The atRA-RARα complex occupies a characteristic retinoic acid response element (RARE) located in the promoter of target genes. Therefore, we searched for RARE on the mouse Tal2 and found that a RARE-like element was located in the intron. We also found that a TATA-box-like element was located in the 5'-region of Tal2. Involvement between transcriptional activity and the TATA-box-like element was confirmed in the luciferase assay, and TATA-box binding protein was bound to this element upstream of Tal2 in P19 cells. atRA signaling activated the transcription through the RARE-like element, and RARα was bound to this element on Tal2 in P19 cells. In addition, the interaction between these elements on Tal2 was shown in the chromatin immunoprecipitation assay. These results suggest that the transcription of Tal2 is coordinately mediated by two distal regulatory elements.

The relationship between the scintillation efficiency and the specific-energy loss as well as the decay curves of the GSO:Ce crystals with the Ce concentrations of 0.25, 0.5, 1.5 and 2.5 mol% have been investigated under the irradiation of high-energy electron, proton, alpha particle and the fission fragment excitation. The relationship observed in the GSO:Ce crystals is found to be independent from the Ce concentration, and is explained in terms of the concept of ionization quenching proposed by Birks. The quenching efficiency B of GSO:Ce is found to be about 0.005 (g cm −2 /MeV). The measured decay curves showed the independence of the decay curves for excitations of electrons, alpha particles and fission fragments.

A hard X-ray polarimeter with CdTe detectors has been developed for measurement of the degree of X-ray polarization at synchrotron radiation facilities. It utilizes 90° Compton scattering from the low Z targets. Measurements were performed at both facilities of the beamline BL38B1 in SPring-8 and the beamline BL14A in KEK-PF. The degrees of X-ray polarization for 20 keV X-rays are 99% and 82% at the BL38B1 in SPring-8 and BL14A in KEK-PF, respectively. The polarization degrees in the energy range of 15 and 40 keV correspond to 99.6±0.2% and 96.1±0.2% at the beamline BL38B1 in SPring-8. The analyzing power of the polarimeter was estimated by the Monte Carlo simulation with EGS4. The synchrotron radiation facilities provide highly polarized X-ray beams at energies above 15 keV.

The performance of the optical imaging capillary gas proportional counter (CGPC) was investigated using polarized X-rays with an energy of 15 keV at SPring-8. The CGPC with a fill gas of Ar+8% CH 4 +2% TMA at 1 atm was operated at a gas gain of 15 000. The CGPC was irradiated by a polarized X-ray beam in the center region using a slit of 300 μm×300 μm. Images of single photoelectron tracks were obtained by an image-intensified CCD camera combined with the CGPC through a lens system. The average distance between the starting point and the barycenter for single photoelectron tracks was 1.1 mm. The angular distribution is obtained from the directions of the lines connected between the starting point and the barycenter for each image of the photoelectron tracks. From a least-squares fitting, the modulation factor was 25.1±2.0% for the X-rays with a polarization degree of 99%.

A high-energy X-ray imager using a [128×128] matrix of YAlO 3 :Ce crystals has been developed for use in high-energy X-ray diffraction and scattering measurements at SPring-8. We demonstrate its application to high-resolution Compton scattering from aluminum or niobium, and a high-energy X-ray diffraction of liquid Zinc.

The fact that high school students have little sense of obeying the rules and have bad manners has a serious problem recently. In this study, the actual situation in the family of high school students was investigated. The data obtained by the investigation was compared with that of junior high school students, which led to some findings. The present situation is that although they live with their families, they are also isolated psychologically after they enter high school. They cannot follow what they have been taught and they lack discipline, nor can they accept the values of their family. Judging from these situations, the problem in home economics education that confronts us is to help them have closer relationships with the other people in their family and good communication with their parents.

A data acquisition system has been developed specifically for a high-energy X-ray area detector called YAP imager. The position encoders are the central modules in the data acquisition system, which are high-speed logic processing modules, highly versatile, with a programmable logic device (PLD) embedded. In the present work, the throughput rate of the data acquisition system has been examined as a function of the trigger rate up to 5 Mcps.

A 128-channel microstrip Germanium detector system has been developed to efficiently detect Compton-scattered X-rays and to effectively reject the background X-rays associated in the Compton spectrometer of the high-energy inelastic scattering beamline at the SPring-8 facility. In order to handle the large number of the readout channels, four 32-parallel-input front-end hybrid boards have been adopted as charge-sensitive pre-amplifiers and discriminators, which are currently controlled by a Windows-based PC data-acquisition system.

An X-ray imaging detector called YAP imager has been developed for high-energy X-ray region at the SPring-8 facility. It possesses a [128×128] matrix of YAlO 3 :Ce crystals, each element having a volume of 1×1×6 mm 3 . A NIM logic module using programmable logic device chip was also developed as a position encoder. The YAP imager has been applied for some applications with a thermal barrier coating material and multi-layer metal sheets targets in the incident X-ray energy region of 70–150 keV. Direct X-ray beam profile at 100 keV was also measured.

Two-dimensional pixel detector, called “YAP Imager”, was designed for SPring-8 high flux synchrotron radiation facilities in high energy X-ray or γ-ray region. It is based on YAlO3:Ce crystals (YAP) with wavelength shifting fibers readout. The sensitive area of the imager is 132×132 mm2 and it is composed of an array of 1×1×6 mm3 YAP pillars. To supply two-dimensional readout two fiber layers (Kuraray B1(4 0 0)) with 128 fiber each are fixed at the top and bottom of the crystal array in orthogonal directions and optically connected with 8+8 H6568 (Hamamatsu) 16-anodes PMs. The obtained performances of the YAP Imager allow one to get a reliable imaging digital device without geometrical distortions with a spatial resolution close to 1 mm and ∼30% detection efficiency in 100 keV energy range.

We reported that cannabidiolic acid (CBDA), a non-psychotropic constituent of fiber-type cannabis plants, down-regulates the mRNA expression of cyclooxygenase-2 (COX-2) in highly aggressive MDA-MB-231 human breast cancer cells. However, the molecular mechanism(s) underlying the CBDA suppression of COX-2 have not yet been elucidated in detail. In MDA-MB-231 cells, COX-2 expression is known to be tightly regulated by the transcriptional activity of activator protein-1 (AP-1), which is composed of a heterodimer of c-Fos and c-Jun. AP-1-mediated transcriptional activity was inhibited by CBDA in a dose-dependent manner. The expression of c-fos was maintained at markedly lower levels (0.035) than basal c-jun expression levels (1.0), implicating c-fos as a limiting factor in the regulation of COX-2. Analyses indicated that CBDA abrogated the expression of c-fos mRNA without affecting c-jun. Collectively, these results suggest that CBDA abolishes the expression of COX-2 by interfering with AP-1 activity in MDA-MB-231 cells.

DNA is constantly being oxidized, and oxidized DNA is prone to mutation, moreover, guanine is highly sensitive to several oxidative stressors. Several oxidatively damaged forms of guanine—including 2,2,4-triamino-5(2H)-oxazolone (Oz), iminoallantoin (Ia), and spiroiminodihydantoin (Sp)—can be paired with guanine, and cause G:C-C:G transversions. Previous findings indicate that guanine is incorporated more efficiently opposite Oz than opposite Ia or Sp, and that these differences in efficiency cannot be explained by differences in the stabilities of G:Oz, G:Ia, and G:Sp base pairs calculated ab initio. Here, to explain previous experimental result, we used a 3-base-pair model DNA duplex to calculate the difference in the stability and the distortion of DNA containing a G:Oz, G:Ia, or G:Sp base pair. We found that the stability of the structure containing 5ꞌ and 3ꞌ base pairs adjacent to G:Oz was more stable than that containing the respective base pairs adjacent to G:Ia or G:Sp. Moreover, the distortion of the structure in the DNA model duplex that contained a G:Oz was smaller than that containing a G:Ia or G:Sp. Therefore, our discussion can explain the previous results involving translesion synthesis past an oxidatively damaged guanine.

Summary • The effects of free radicals, ·OH and ·NO, generated in polluted dew water on needles of Pinus densiflora (Japanese Red pine) were investigated. • ·OH-generating solutions (HOOH with Fe(III) and oxalate ion; ·OH treatment) and ·OH- and ·NO-generating solutions (NO2−; ·OH/·NO treatment) were regulated at 25, 50 and 100 µmol and pH 4.4. HOOH only (HOOH treatment) was used as a control solution. Solutions were applied as a mist to the needle surface of P. densiflora seedlings before dawn twice a week for 3 months. • Within a month, net photosynthesis at near saturating irradiance (Pn) and stomatal conductance (gl) of ·OH-treated needles decreased with increasing solution concentration. The HOOH treatment had no effects on any of the measured parameters. Therefore, ·OH in the artificial dews caused the decreases in Pn and gl. In ·OH/·NO-treated needles, gl increased during the experiment, but Pn was unchanged. In all experiments, the characteristics of PSII were not significantly altered. • Free radicals in polluted dew water have harmful effects on the photosynthesis of P. densiflora and compound effects of ·OH and ·NO are different.

Two prototypes of a one-dimensional microstrip germanium detector were fabricated with seven strips, having different pitches of 200 and 350 μm. Owing to its insensitivity to hole-diffusion process, the latter one has attained a spatial resolution as high as 350 μm, an energy resolution better than 1.4%, and a peak efficiency around 50% at an X-ray energy of 80 keV.

The performance of a Micro-Strip Gas Chamber in solution X-ray scattering was studied at the RIKEN structural biology beamline I of the SPring-8 facility. The practical dynamic range was confirmed to be ∼1,000,000 : 1 by measuring S −4 decay from a polystyrene latex solution. Steep troughs of scattering profile from an apoferritin solution were clearly obtained without smearing. An unfolding process of a pH jump of cytochrome c was measured. A time resolution of 500 μs was achieved.

A prototype of YAP(Ce) imager has been characterized with a high energy SR beam at the SPring-8 Facility, which has a [8×8] YAP(Ce) crystal matrix with optical separators. It has attained a 2D spatial resolution of 1 mm×1 mm with a detection efficiency higher than 50% in the energy region from 72 keV up to 84 keV.

DNA is damaged by various oxidative stresses. Oxidized DNA can increase mutations and the risk of cancer. Guanine is highly sensitive to several oxidative stresses due to its low oxidation potential. It is known that 2,2,4-triamino-5(2H)-oxazolone (Oz), iminoallantoin (Ia) and spiroiminodihydantoin (Sp) are oxidized guanine lesions. These oxidized bases can be paired with guanine and cause G:C-C:G transversions. Although our previous results showed more effective incorporation of guanine opposite Oz compared to that opposite Ia or Sp (K. Kino et al., ChemBioChem, 2009), Oz:G base pair was less stable than Ia:G or Sp:G base pair by ab initio calculation (M. Suzuki et al., Molecules, 2012). Oz:G forms two hydrogen bonds and is planar, while Ia:G and Sp:G have three hydrogen bonds and are nonplanar. This difference can be due to the fact that Ia:G and Sp:G contain a sp3 carbon but not Oz:G. Since stacking planar base pairs in DNA significantly enhances the stability of DNA duplex, we investigate whether the stability of DNA duplex containing the oxidized lesion can be accounted for by the stacking effect in this study. The structure of DNA duplex containing Oz:G was the most stable. This our data agreed with the previous results that translesion synthesis across Oz was more effective than Ia or Sp.

The deposition of Amyloid beta peptides (Aβ) in the formation of amyloid fibrils is believed to be causally linked to Alzheimer's disease. A short Aβ fragment (KLVFF; Aβ16-20) can bind full-length Aβ. The Aβ recognition peptide including KLVFF was attached with hydrophilic groups, and then the product altered the Aβ aggregation pathways and inhibited Aβ toxicity (Tjernberg, L. O. et al. J. Biol. Chem. 1996, 271, 8545-8548. ). Since flavins is widely known as biological oxidation reagents, the flavin-linked KLVFF is likely to directly hydroxylate aggregated Aβ fibrils and then disrupt the aggregated Aβ fibril. 2-Aminoethanethiol derivatives, such as cysteine, is reacted with aldehydes, and five-membered heterocyclic ring is formed via formation of imine. Since formylmethylflavin (FMF) contains aldehyde group, FMF is likely to bind cysteine. Then, the peptides containing Aβ recognition region and cysteine, such as CKLVFF, also can be attached with FMF to form the flavin-linked KLVFF. The preliminary experiment of this reaction, the reaction between FMF and cysteine, was investigated. FMF (2.84 mg, 10 μmol) was suspended in phosphate buffer (pH 7, 10 ml), and cysteine (2.42 mg, 20 μmol) was added. The suspension was stirred at 65oC for 1h. As a result, FMF was completely reacted, and flavin-linked cystein were detected using HPLC and ESI-MS.

The decline of Japanese red pine trees (Pinus densiflora Sieb. et Zucc.) at Mt. Gokurakuji (693 m a.s.l.), 30 km west of Hiroshima city, west Japan, was studied. The effects of air pollution and acid deposition on the physiological characteristics of the trees, especially those of the needles, were investigated. Ozone concentration was not correlated with the physiological status of the needles and SO2 concentration was not high in the declined area. NO2 concentration correlated negatively with needle longevity while it correlated positively with ethylene emission from 1-year-old needles. Average needle longevity was about 2.8 years in non-declined areas; however the longevity was 1.3 years in the most polluted area. The minimal fluorescence at night (F0)of 1-year-old needles decreased with increasing NO2 concentration. The maximum stomatal conductance (gl), net photosynthesis (Pn)and intercellular CO2 concentration (Ci) in the declined areas were lower than in the non- declined areas (about 50%, 30% and 20% lower, respectively). The lower Cisuggested that the major part of the decrease in Pncan be explained by stomatal restriction. The soil pH, N content and C/N ratio showed no significant difference between the declined and non-declined areas. The physiological disorders of needles were due to the damage by air pollutants, and important roles of NO2 are suggested. Lowering of Pn and the shortening of needle longevity appear to be the main causes of the decline in pines in the forest decline area.

A 4×4 array structure of 16 identical CCD X-ray detector modules, called the multiple CCD X-ray detector system (MCCDX), was submitted to its first synchrotron radiation experiment at the protein crystallography station of the RIKEN beamline (BL45XU) at the SPring-8 facility. An X-ray diffraction pattern of cholesterol powder was specifically taken in order to investigate the overall system performance.

Selenoprotein P is an extracellular protein containing presumably 10 selenocysteines that are encoded by the UGA stop codon in the open reading frame of the mRNA. The function of selenoprotein P is currently unknown, although several indirect lines of evidence suggest that selenoprotein P is a free radical scavenger. We first developed a conventional procedure to isolate selenoprotein P from human plasma. Next, we investigated the reactivities of selenoprotein P against various hydroperoxides in the presence of glutathione. Although selenoprotein P reduces neither hydrogen peroxide nor tertiary butyl hydroperoxide, it does reduce phospholipid hydroperoxide such as 1-palmitoyl-2-(13-hydroperoxy-cis-9,trans-11-octadecadienoyl)-3-phosphatidylcholine hydroperoxide. Kinetic analysis demonstrated atert-uni ping-pong mechanism, similar to those described for classical glutathione peroxidase and phospholipid hydroperoxide glutathione peroxidase. Not only glutathione, but also dithiothreitol, mercaptoethanol, cysteine, and homocysteine, were effective as reducing substances, as in the case of phospholipid hydroperoxide glutathione peroxidase. These results show that selenoprotein P functions as a phospholipid hydroperoxide glutathione peroxidase in extracellular fluids.