Design of JT-60SA core Thomson scattering diagnostic system.

An incoherent Thomson scattering diagnostic will be installed in the JT-60SA tokamak to measure electron temperature and electron density profiles. The target radial spatial resolution is 25 mm with 46 spatial channels. The accuracy in electron temperature and density is a few percent at ne = 7.5 × 1019 m-3, which is the expected value in the plasma core. This paper presents the designs of collection optics, fibers with their alignment system, and polychromators. The collection optics overcomes unique issues for superconducting fusion devices, i.e., limited design space, high-temperature measurements, and harsh radiation condition. When in several years the more performing plasma will generate intense nuclear radiation, the lens materials of the optics can be replaced by radiation resistant glasses without major changes in the lens holder. It will prevent transmission degradation and keep stable measurement accuracy.

A model of plasma current through a hole of Rogowski probe including sheath effects.

In TST-2 Ohmic discharges, local current is measured using a Rogowski probe by changing the angle between the local magnetic field and the direction of the hole of the Rogowski probe. The angular dependence shows a peak when the direction of the hole is almost parallel to the local magnetic field. The obtained width of the peak was broader than that of the theoretical curve expected from the probe geometry. In order to explain this disagreement, we consider the effect of sheath in the vicinity of the Rogowski probe. A sheath model was constructed and electron orbits were numerically calculated. From the calculation, it was found that the electron orbit is affected by E × B drift due to the sheath electric field. Such orbit causes the broadening of the peak in the angular dependence and the dependence agrees with the experimental results. The dependence of the broadening on various plasma parameters was studied numerically and explained qualitatively by a simplified analytical model.

The hnRNP-Htt axis regulates necrotic cell death induced by transcriptional repression through impaired RNA splicing.

In this study, we identify signaling network of necrotic cell death induced by transcriptional repression (TRIAD) by α-amanitin (AMA), the selective RNA polymerase II inhibitor, as a model of neurodegenerative cell death. We performed genetic screen of a knockdown (KD) fly library by measuring the ratio of transformation from pupa to larva (PL ratio) under TRIAD, and selected the cell death-promoting genes. Systems biology analysis of the positive genes mapped on protein-protein interaction databases predicted the signaling network of TRIAD and the core pathway including heterogeneous nuclear ribonucleoproteins (hnRNPs) and huntingtin (Htt). RNA sequencing revealed that AMA impaired transcription and RNA splicing of Htt, which is known as an endoplasmic reticulum (ER)-stabilizing molecule. The impairment in RNA splicing and PL ratio was rescued by overexpresion of hnRNP that had been also affected by transcriptional repression. Fly genetics with suppressor or expresser of Htt and hnRNP worsened or ameliorated the decreased PL ratio by AMA, respectively. Collectively, these results suggested involvement of RNA splicing and a regulatory role of the hnRNP-Htt axis in the process of the transcriptional repression-induced necrosis.

In utero gene therapy rescues microcephaly caused by Pqbp1-hypofunction in neural stem progenitor cells.

Human mutations in PQBP1, a molecule involved in transcription and splicing, result in a reduced but architecturally normal brain. Examination of a conditional Pqbp1-knockout (cKO) mouse with microcephaly failed to reveal either abnormal centrosomes or mitotic spindles, increased neurogenesis from the neural stem progenitor cell (NSPC) pool or increased cell death in vivo. Instead, we observed an increase in the length of the cell cycle, particularly for the M phase in NSPCs. Corresponding to the developmental expression of Pqbp1, the stem cell pool in vivo was decreased at E10 and remained at a low level during neurogenesis (E15) in Pqbp1-cKO mice. The expression profiles of NSPCs derived from the cKO mouse revealed significant changes in gene groups that control the M phase, including anaphase-promoting complex genes, via aberrant transcription and RNA splicing. Exogenous Apc4, a hub protein in the network of affected genes, recovered the cell cycle, proliferation, and cell phenotypes of NSPCs caused by Pqbp1-cKO. These data reveal a mechanism of brain size control based on the simple reduction of the NSPC pool by cell cycle time elongation. Finally, we demonstrated that in utero gene therapy for Pqbp1-cKO mice by intraperitoneal injection of the PQBP1-AAV vector at E10 successfully rescued microcephaly with preserved cortical structures and improved behavioral abnormalities in Pqbp1-cKO mice, opening a new strategy for treating this intractable developmental disorder.

Follow-up of a self-resolving renal pseudoaneurysm using contrast-enhanced power Doppler ultrasonography.

It has been standard practice to embolise a pseudoaneurysm caused by penetrating trauma whenever it is found, even in the absence of overt symptoms. This is a case report of a renal pseudoaneurysm (RPA) caused by a stab wound, which was safely monitored and followed using colour Doppler ultrasonography. On day 1, angiography showed a pseudoaneurysm of the renal artery in the parenchyma and ultrasonography showed blood flow into the pseudoaneurysm. Although abnormal blood flow into the kidney was seen, there appeared to be no leakage of blood from the pseudoaneurysm. The abnormal flow disappeared on day 12 and the area of the pseudoaneurysm became unclear from day 13. This report suggests the possibility that RPA caused by a stab wound could be an indication for conservative therapy under the following conditions: the RPA is detected initially; close monitoring using a colour Doppler ultrasound is possible; there is no leakage of blood from the right subclavian artery and there is a 2-week period of observation.

Periodic metallo-dielectric structure in diamond.

Intense ultrashort light pulses induce three dimensional localized phase transformation of diamond. Photoinduced amorphous structures have electrical conducting properties of a maximum of 64 S/m based on a localized transition from sp(3) to sp(2) in diamond. The laser parameters of fluence and scanning speed affect the resultant electrical conductivities due to recrystallization and multi-filamentation phenomena. We demonstrate that the laser-processed diamond with the periodic cylinder arrays have the characteristic transmission properties in terahertz region, which are good agreement with theoretical calculations. The fabricated periodic structures act as metallo-dielectric photonic crystal.

Hyperactive mutants of mouse D-aspartate oxidase: mutagenesis of the active site residue serine 308.

The role of Ser-308 of murine D-aspartate oxidase (mDASPO), particularly its side chain hydroxyl group, was investigated through the use of site-specific mutational analysis of Ser-308. Recombinant mDASPO carrying a substitution of Gly, Ala, or Tyr for Ser-308 was generated, and fused to either His (His-mDASPO), or glutathione S-transferase, His, and S (GHS-mDASPO) at its N-terminus. Wild-type His-mDASPO or GHS-mDASPO or their mutant derivatives were expressed in Escherichia coli and purified by affinity chromatography. All purified recombinant proteins had functional DASPO activity. The Gly-308 and Ala-308 mutants had significantly higher catalytic efficiency towards D-Asp and N-methyl-D-Asp, and a higher affinity for flavin adenine dinucleotide (FAD) compared to the wild-type enzyme. The Tyr-308 mutant had lower catalytic efficiency and binding capacity. These results suggest that the side chain hydroxyl group of a critical residue of mDASPO, Ser-308, down-regulates enzymatic activity, substrate binding, and FAD binding. This study provides information on the active site of DASPO that will considerably enhance our understanding of the biological significance of this enzyme.

In situ monitoring of friction surfaces and their sequence pattern analysis.

Friction occurs between solid surfaces, and even sometimes on lubricated surfaces. To understand tribological subjects, it is important to know the changes that occur in friction surfaces. In this study, a laser strobe technique is applied to a friction surface observation. The recorded surface images were analysed using pattern-matching methods and their correlations are discussed. A test using pin-on-plate methods with carbon steels was performed using a reciprocating motion speed of 10 Hz for 4.9 N. A pulsed laser light (Nd:YAG SHG=532 nm, 5 ns per pulse) was irradiated onto the friction surface. It was induced using an optical microscope that was located just to the side of the pin. The laser pulse was synchronized with the plate motion, which was a trigger of the laser pulse. The surface image was stored for every cycle. These sequences were calculated and their correlations were analysed as a function of the surface pattern and the friction track size and shape. Analysis revealed that some groups were distinguishable as parameters of the damage size and shape.

Molecular cloning of a cDNA encoding mouse D-aspartate oxidase and functional characterization of its recombinant proteins by site-directed mutagenesis.

The cDNA encoding D-aspartate oxidase (DASPO) was cloned from mouse kidney RNA by RT-PCR. Sequence analysis showed that it contained a 1023-bp open reading frame encoding a protein of 341 amino acid residues. The protein was expressed in Escherichia coli with or without an N-terminal His-tag and had functional DASPO activity that was highly specific for D-aspartate and N-methyl-D-aspartate. To investigate the roles of the Arg-216 and Arg-237 residues of the mouse DASPO (mDASPO), we generated clones with several single amino acid substitutions of these residues in an N-terminally His-tagged mDASPO. These substitutions significantly reduced the activity of the recombinant enzyme against acidic D-amino acids and did not confer any additional specificity to other amino acids. These results suggest that the Arg-216 and Arg-237 residues of mDASPO are catalytically important for full enzyme activity.

Biochemistry of D-aspartate in mammalian cells.

Recent investigations have shown that D-aspartate (D-Asp) plays an important physiological role(s) in the mammalian body. Here, several recent studies of free D-Asp metabolism in mammals, focusing on cellular localization in tissues, intracellular localization, biosynthesis, efflux, uptake and degradation are reviewed. D-Asp in mammalian tissues is present in specific cells, indicating the existence of specific molecular components that regulate D-Asp levels and localization in tissues. In the rat pheochromocytoma cell line (PC12) and its subclones, D-Asp is synthesized intracellularly, most likely by Asp racemase(s). Endogenous D-Asp apparently has two different intracellular localization patterns: cytoplasmic and vesicular. In PC12 cells, D-Asp release can occur through three distinct pathways: 1) spontaneous, continuous release of cytoplasmic D-Asp, which is not associated with a specific stimulus; 2) release of cytoplasmic D-Asp via a volume-sensitive organic anion channel that connects the cytoplasm and extracellular space; 3) exocytotic discharge of vesicular D-Asp. Under certain conditions, D-Asp can be released via a mechanism that involves the L-Glu transporter. D-Asp is thus apparently in dynamic flux at the cellular level to carry out its physiological function(s) in mammals.

Cytoplasmic localization and efflux of endogenous D-aspartate in pheochromocytoma 12 cells.

In our previous reports [Z. Long, H. Homma, J.-A. Lee, T. Fukushima, T. Santa, T. Iwatsubo, R. Yamada, K. Imai, FEBS Lett. 434 (1998) 231-235; Z. Long, M. Sekine, M. Adachi, T. Furuchi, K. Imai, N. Nimura, H. Homma, Arch. Biochem. Biophys. 404 (2002) 92-97], we demonstrated for the first time that D-aspartate (D-Asp) is actually synthesized in cultured mammalian cells such as PC12, MPT1, and GH3 cells. After its synthesis, this unique amino acid is spontaneously and continuously released into the extracellular space during cell culture. In the current study, we characterized two different types of D-Asp efflux in PC12 cells. One is a spontaneous and continuous form of release of cytoplasmic origin that does not involve exocytotic efflux of vesicular origin. Endogenous D-Asp is predominantly localized to the cytoplasm of cells, and this form of D-Asp release presents a striking contrast to exocytotic, quantal discharge of vesicular dopamine. The other form of efflux is also of cytoplasmic origin and occurs through volume-sensitive organic anion channels that are opened upon hyposmotic stimuli. Interestingly, this latter form of efflux is potentiated by acetylcholine stimulation.

Semi-micro liquid chromatography of aromatic amino acid metabolites using isocratic elution and column switching.

The concentrations of catecholamine-related compounds in body fluids reflect sympathetic nerve functions. Measuring the enzyme activity of these metabolic pathways will improve diagnosis since a variety of symptoms are reported. An isocratic elution system with two column switching valves was developed using three types of semi-micro columns for fast chromatographic analysis of catecholamine related compounds. Columns are a pentyl-bonded phase, 50 x 2.1 mm i.d., a phenylhexyl-bonded phase, 100 x 2.1 mm i.d. and an octadecyl-bonded phase, 100 x 2.1 mm i.d. The separation of 20 standard compounds was achieved within 25 min using reversed-phase ion-pair liquid chromatography with an electrochemical detector. This new system was applied for analysis of catecholamine-related compounds in pig brain, since pigs are a widely used animal model for transgenic manipulation of neural genes, and MHPG (or VMA), DOPAC, DOPA, NE, EP, DA, 5HTP and 5HIAA were quantified.

[Hepatic and splenic arterial infusion chemotherapy after transcatheter peripancreatic arterial embolization for patients with inoperable adenocarcinoma of the pancreas].

Thirty-one patients with advanced pancreatic carcinoma and liver metastases were treated by hepatic and splenic arterial infusion chemotherapy after transcatheter peripancreatic arterial embolization. The response rate for these 31 patients was 61.3%, with a mean survival period of 17.8 +/- 3.2 months and a 50% survival period of 12 months. By site of the primary tumor, the response rate for pancreatic head and body carcinoma was 81%, with a mean survival period of 21.6 +/- 4.0 months and a 50% survival period of 17 months, whereas the response rate for pancreatic caudal carcinoma was 20%, with a mean survival period of 6.1 +/- 0.5 months and a 50% survival period of 6 months. We believe that the current chemotherapy is an effective treatment for advanced pancreatic cancer with liver metastases.

[Implantation of a dual chambers port for hepatic and splenic arterial infusion chemotherapy in advanced pancreatic carcinoma with multiple liver metastasis].

Dual chambers ports were implanted in 7 patients with advanced pancreatic carcinoma and metastatic liver tumors to connect a 3.3 Fr catheter as an indwelling catheter. In comparison with the implantation of a pair of Single chamber ports, implanting a Dual chambers port entails some technical difficulties, but has some benefits in terms of stabler placement, a smaller incision, reduction of medical fees, and improved QOL of patients.

Determination of D- and L-aspartate in cell culturing medium, within cells of MPT1 cell line and in rat blood by a column-switching high-performance liquid chromatogrpahic method.

HPLC fluorometric methods have been used to analyze trace amounts of D-amino acids in biological samples. In this study, we established an expedient column-switching fluorometric HPLC system that would improve the analysis of D-amino acids, in particular D-aspartate (Asp). Our system consists of the fluorogenic derivatization of amino acids with NBD-F and two chromatographic steps, one that separates individual amino acids in reverse phase mode and another that separates the chiral forms of each amino acid in normal-phase mode. The two separation steps are linked through a trapping column by an automated column-switching system. In addition, sample preparation is simplified and improved, where trichloroacetic acid is used for deproteinization, and borate buffer, pH 9.5 is employed for the fluorescent derivatization. The detection limit for D-Asp in culturing medium is 5 nM. The resulting peak heights correlated well with concentrations that ranged from 12.5 to 250 nM for both D- and L-Asp. The present method was applied to determine D- and L-Asp levels in cell culturing medium, and within cells of MPT1 cell line. The detected cellular levels of D- and L-Asp agree with those detected by our previous method. In addition, this method was used to measure D- and L-Asp levels in rat blood samples, and the results are consistent with the reported values.

Implantation of octacalcium phosphate nucleates isolated bone formation in rat skull defects.

OBJECTIVE: Our previous radiographic examinations have indicated that the synthetic octacalcium phosphate (OCP) may provide the core for nucleating multiple osteogenic sites in the experimentally created cranial defect. DESIGN: The present study was designed to confirm the possibility that the implanted OCP causes the osteoinduction as well as the osteoconduction in the rat cranial defect. MATERIALS AND METHODS: Standardized defects were created in male Wistar rat calvaria, and the OCP granules were implanted into the defect. The sham operated rats were processed in the same way except that nothing was implanted. The rats were fixed at 4 weeks after implantation of OCP or the sham operation. We examined bone formed on the implanted OCP, analyzing serial sections histologically combined with immunohistochemistry for the bone specific protein, osteocalcin. RESULTS: In the defects treated with OCP, the radiopacity was scattered throughout the defect besides being observed along the defect margin of the parietal bone. Examination of the serial sections showed that some of new bones on the implanted OCP were formed away from the defect margin of the parietal bone with regard to both histological identification and specific molecular marker. CONCLUSIONS: The present study suggested that the implanted OCP can serve as a core for initiating bone formation and cause the osteoinduction as well as the osteoconduction in the defect.

Localization, transport, and uptake of D-aspartate in the rat adrenal and pituitary glands.

Large amounts of D-aspartate (D-Asp) are present in the rat adrenal and pituitary glands. D-Asp is thought to be synthesized in the mammalian body and also accumulates in various tissues following intraperitoneal or intravenous administration. This report examines the origins of D-Asp in the adrenal and pituitary glands. We administered D-Asp to male rats intraperitoneally and immunolocalized this exogenous D-Asp in adrenal and pituitary tissue, using an anti-D-Asp antiserum which was previously developed in our laboratory. D-Asp levels in the rat adrenal gland have been shown to undergo a transient increase at 3 weeks of age and to decrease rapidly thereafter. We found that in the adrenal gland, exogenous D-Asp administered intraperitoneally was incorporated into the same region of the adrenal cortex in which endogenous D-Asp was present. By Northern and Western blot analysis and immunohistochemistry of glutamate (Glu) transporter, we also found that expression of the Glu transporter (GLAST), which has an affinity for D-Asp, transiently increased at 3 weeks of age and that localization patterns of the Glu transporter within the tissue were almost coincident with those of endogenous D-Asp. These observations suggest that D-Asp in the adrenal cortex of 3-week-old male rats is primarily acquired by uptake from the vascular system. We have previously shown that D-Asp is specifically localized in prolactin (PRL)-containing cells in the anterior lobe of the adult rat pituitary gland. Here we report that in the pituitary gland, exogenous D-Asp accumulated in endothelial cells, but not in PRL-containing cells. Northern and Western blot analysis and immunohistochemistry of Glu transporter revealed that developmental changes in the Glu transporter (GLAST) expression did not correlate with tissue levels of D-Asp and that the Glu transporter was not expressed in PRL-containing cells. These observations suggest that, in contrast to the adrenal gland, most of the D-Asp in the pituitary gland of adult male rats originates inside the gland itself.