In situ mRNA hybridization technique for analysis of human telomerase RNA in gastric precancerous and cancerous lesions

Telomerase, the ribonucleoprotein enzyme that elongates telomerase, is repressed in normal somatic cells but is reactivated during tumor progression. The purpose of this study was to investigate the localization of human telomerase RNA (hTR) expression in human gastric precancerous and cancerous lesions by using in situ mRNA hybridization (ISH) with avidin-biotin staining. We also examined telomerase activity in these lesions by using hybridization protection assay connected with a telomeric repeat amplification protocol (TRAP/HPA). Analyzed tissue samples were as follows; 132 cases of chronic atrophic gastritis without intestinal metaplasia, 115 incomplete-type intestinal metaplasias, 40 complete-type intestinal metaplasias, 23 hyperplastic polyps, 23 tubular adenomas and 26 adenocarcinomas. In ISH analysis, high levels of hTR expression were observed preferentially in the nuclei at the single-cell level. hTR-expressing cells in carcinomas and adenomas were significantly more frequent than those of the other lesions (P < 0.001). The expression pattern of hTR in carcinoma and adenoma tissues was heterogeneous and similar intratumor heterogeneity was detected in Ki-67 immunoreactivity. Infiltrating lymphocytes in tissue also exhibited high levels of hTR expression. In TRAP/HPA analysis, carcinomas had significantly more frequent positivity for telomerase activity and a higher level of telomerase activity than the other lesions (P < 0.05). However, the amount of telomerase activity did not parallel the expression level of hTR. Our data suggest that hTR expression increases in the early stages of stomach carcinogenesis and that sufficient synthesis of hTR is a prerequisite for telomerase reactivation in tumorigenesis.     

9H-xanthene-2,7-diols as antioxidants for autoxidation of linoleic acid

The antioxidant activities of 9H-xanthene-2,7-diols and α-tocopherol were studied during the oxidation of linoleic acid in a homogeneous solution and in an aqueous micelle dispersion. The antioxidant activities of 9H-xanthene-2,7-diols for both systems were 1.0–2.4 times greater relative to α-tocopherol. In addition, the 1,3,4,5,6,8-hexamethylxanthene-2,7-diol showed less cytotoxicity toward human fibroblasts than did 2,6-di-t-butyl-4-methylphenol.     

Novel rotor position extraction based on carrier frequency component method (CFCM) using two reference frames for IPM drives

In this paper a novel interior permanent-magnet (IPM) motor's rotor position extraction method from the carrier-frequency component signal, derived from pulsewidth-modulated (PWM) inverter switching, using two reference frames is presented. This method has been utilized for IPM motor vector control without a mechanical rotor position detector, extracting rotor position angle from the switching carrier-frequency (10 kHz) component current. It is effective for IPM motors, which have magnetic saliency, sinusoidal distributed stator winding, and are supplied by a PWM voltage-source inverter. The performance of two IPM motors' vector control without mechanical rotor position detector utilizing this method has been investigated. Experimental results demonstrating good dynamic and steady-state performance achieved are presented and discussed.     

Phase-slip centers of superconducting indium bridges with variable thickness in a magnetic field

We have measured current-voltage (I–V) curves in magnetic fieldsH, for indium variable-thickness bridges whose strips were quasi-one-dimensional superconductors. TheI–V curves take three different types depending on theH regions. One has hysteresis due to phase-slip centers. The others have no hysteresis. The critical current againstH shows hysteresis owing to the surface currents induced byH. The modification of the pair-breaking time was introduced to treat theH dependence of the hysteresis ofI–V curves.     

Interaction of rat lin-10 with brain-enriched F-actin-binding protein, neurabin-II/spinophilin

We have recently isolated a rat homologue of the Caenorrhabditis elegans lin-10 product. Although rat lin-10 is expressed in the cytosol and membrane fractions of various tissues, it is distributed only in the membrane fraction in brain where it is enriched in the synaptic plasma membrane and postsynaptic density fractions. We have isolated here a rat lin-10-interacting protein from rat brain and identified it to be neurabin-II/spinophilin, which has recently been isolated as a protein interacting with protein phosphatase I and F-actin. Neurabin-II/spinophilin is ubiquitously expressed but enriched in brain, especially in the synaptic plasma membrane and postsynaptic density fractions. We discuss the physiological significance of the interaction of rat lin-10 with neurabin-II/spinophilin.     

A three‐phase voltage‐source PWM inverter system characterized by sinusoidal output voltage with neither common‐mode voltage nor normal‐mode voltage

This paper deals with an inverter system integrating a small‐rated passive EMI filter with a three‐phase voltage‐source PWM inverter. The purpose of the EMI filter is to eliminate both common‐mode and normal‐mode voltages from the output voltage of the inverter. The motivation of this research is based on the well‐known fact that the higher the carrier or switching frequency, the smaller and the more effective the EMI filter. An experimental system consisting of a 5‐kVA inverter, a 3.7‐kW induction motor, and a specially designed passive EMI filter was constructed to verify the viability and effectiveness of the EMI filter. As a result, it is shown experimentally that both three‐phase line‐to‐line and line‐to‐neutral output voltages look purely sinusoidal as if the inverter system were an ideal variable‐voltage, variable‐frequency power supply when viewed from the motor terminals. This results in complete solution of serious issues related to common‐mode and normal‐mode voltages produced by the inverter. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(4): 88–96, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10206     

A 320 MFLOPS CMOS floating-point processing unit for superscalarprocessors

A CMOS pipelined floating-point processing unit (FPU) for superscalar processors is described. It is fabricated using a 0.5 μm CMOS triple-metal-layer technology on a 61 mm² die. The FPU has two execution modes to meet precise scientific computations and real-time applications. It can start two FPU operations in each cycle, and this achieves a peak performance of 160 MFLOPS double or single precision with an 80 MHz clock. Furthermore, the original computation mode, twin single-precision computation, double the peak performance and delivers 320 MFLOPS single precision. Its full bypass reduces the latency of operations, including load and store, and achieves an effective throughput even in nonvectorizable computations. An out-of-order completion is provided by using a new exception prediction method and a pipeline stall technique     

Huntington's disease: trinucleotide disease or polyglutamine disease?

Huntington's disease (HD) is associated with expansion of an unstable CAG repeat. Using antibodies against the synthetic peptide corresponding to the sequence of HD gene IT15, we have identified the HD gene product in normal lymphocytes as a approximately 350kDa protein by immunoblot analysis. Moreover, when a modified SDS-PAGE using a low concentration of methylenbisacrylamide was run longer, abnormal immunoreactive bands larger than normal ones were found exclusively in HD samples. We also found double bands in HD brain homogenate samples. Recently on the other CAG repeat diseases, such as SCA1 and DRPLA, abnormal gene products were also reported. These results demonstrate the existence of the expanded CAG repeat gene products and open a possibility that the expanded polyglutamine stretch may really participate in the pathological process of the CAG repeat diseases.