Optimal aerobic cultivation method for 1,4-dihydroxy-2-naphthoic acid production by Propionibacterium freudenreichii ET-3

To investigate the effects of oxygen supply on Propionibacterium freudenreichii ET-3 metabolism and 1,4-dihydroxy-2-naphthoic acid (DHNA) production in detail, the strain was cultured by switching from anaerobic condition to aerobic condition at 72 h (termed anaerobic-aerobic switching culture hereafter) employing different oxygen transfer rates (OTRs) in the range of 0.08-0.90 mg/(l.h). It was found that a 0.08 mg/(l.h) OTR could not change the metabolism or improve the DHNA production of P. freudenreichii ET-3. When the OTR was in the range of 0.23-0.66 mg/(l.h), propionate, which inhibits DHNA production significantly, was consumed during the aerobic phase. Final DHNA concentration increased to 0.22 mM, irrespective of OTR. When the OTR was 0.90 mg/(l.h), a sudden increase in dissolved oxygen (DO) concentration during the aerobic phase resulted in a sudden decrease in DHNA concentration. To attenuate the stresses caused by propionate and oxygen exposure, we designed an optimal cultivation in which the anaerobic and aerobic phases were repeated three times alternately. As a result, propionate concentration was maintained below the level that inhibits DHNA production, and no DO concentration was detected throughout the culture. The final DHNA concentration in this culture was 0.33 mM, which is 2.7-fold that in the anaerobic culture and 1.5-fold that in the anaerobic-aerobic switching culture.     

Specific response of osteoblast-like cells on hydroxyapatite layer containing serum protein

Accelerations of bone-like apatite deposition and cell growth on an electrically polarized ceramic hydroxyapatite have been reported. A relationship between these phenomena was investigated in a previous report, and then it was suggested that osteoblast-like cell’s (MC3T3-E1) growth had relevance to the mineral growth. The effect of the formed apatite layer especially appeared to be on the cell adhesion. The acceleration of cell proliferation on the polarized HAp has been shown using fibroblastic cell (L929) and nerve cell (SK-N-SH) lines, therefore the effect of the layer on L929 and SK-N-SH was investigated to support the mechanism of acceleration of cell proliferation by polarization of HAp. In this study, the effect of the bone-like apatite layer was not confirmed on L929 cell’s growth. On the other hand, the acceleration of nerve cell’s proliferation was confirmed on the formed apatite layer. However, the remarkable improvement of the cell adhesion of SK-N-SH was not confirmed on the apatite layer. Consequently, it was considered that the bone-like apatite containing serum protein obtained by the coprecipitation of bone-like apatite and serum protein has a pronounced role only in the activity of osteoblast-like cells.     

Novel Inhibitor for Downstream Targeting of Transforming Growth Factor-β Signaling to Suppress Epithelial to Mesenchymal Transition and Cell Migration

Cancer metastasis accounts for most of the mortality associated with solid tumors. However, antimetastatic drugs are not available on the market. One of the important biological events leading to metastasis is the epithelial to mesenchymal transition (EMT) induced by cytokines, namely transforming growth-factor-β (TGF-β). Although several classes of inhibitors targeting TGF-β and its receptor have been developed, they have shown profound clinical side effects. We focused on our synthetic compound, HPH-15, which has shown anti-fibrotic activity via the blockade of the TGF-β Smad-dependent signaling. In this study, 10 μM of HPH-15 was found to exhibit anti-cell migration and anti-EMT activities in non-small-cell lung cancer (NSCLC) cells. Although higher concentrations are required, the anti-EMT activity of HPH-15 has also been observed in 3D-cultured NSCLC cells. A mechanistic study showed that HPH-15 inhibits downstream TGF-β signaling. This downstream inhibition blocks the expression of cytokines such as TGF-β, leading to the next cycle of Smad-dependent and -independent signaling. HPH-15 has AMPK-activation activity, but a relationship between AMPK activation and anti-EMT/cell migration was not observed. Taken together, HPH-15 may lead to the development of antimetastatic drugs with a new mechanism of action.     

集成EMI滤波器原理与设计

利用柔性多层带材,提出了一种Electromagnetic Interference(EMI)滤波器的集成结构。该结构单独设计了差模绕组,并将滤波器中所有无源元件都集成在同一磁心中。文章通过建立集成滤波器的分布模型,从差、共模电流分布和磁路的角度,分别阐述了差、共模电感的集成原理,并给出了计算公式和集成结构的设计要点。实验部分比较了在不同差模电感下,差模插入损耗特性和EMI测试结果。实验表明,集成滤波器比分立滤波器体积更小,高频特性改善显著。     

Development of radio frequency transmitters including on‐chip antenna for intelligent human sensing systems

This paper presents the essentials of the development of an integrated smart microsensor system that has been developed to monitor the motion and vital signs of humans in various environments. Integration of RF transmitter technology with complementary metal‐oxide‐semiconductor/micro electro mechanical systems (CMOS/MEMS) microsensors is required to realize wireless smart microsensors for the monitoring system. Sensors for the measurement of body temperature, perspiration, heart rate (pressure sensor), and motion (accelerometers) are candidates for integration on the wireless smart microsensor system. In this paper, the development of radio frequency transmitter (RF) that will be integrated on wireless smart microsensors is presented. A voltage controlled RF‐CMOS oscillator (VCO) has been fabricated for the 300‐MHz frequency band applications. Also, spiral inductors for an LC resonator and an integrated antenna have been realized with a CMOS‐compatible metallization process. The essential RF components have been fabricated and evaluated experimentally. The fabricated CMOS VCO showed a conversion factor from voltage to frequency of about 81 MHz/V. After matching the characteristic impedance (50 Ω) of the on‐chip integrated antenna and the VCO output, more than 5 m signal transmission from the microchip antenna has been observed. The transmitter showed remarkable improvement in transmission power efficiency by correct matching with the microchip antenna. Essential technologies of the RF transmitter for the wireless smart microsensors have been successfully developed. Also, for the 300‐MHz band application, the integrated RF transmitter, with the CMOS oscillator and the on‐chip antenna, has been successfully demonstrated for the first time. Copyright © 2007 Institute of Electrical Engineers of Japan© 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.