Three-Dimensional Analysis of the Ideal Entry Point for Sacral Alar Iliac Screws

Watanabe Noriyuki,Takigawa Tomoyuki,Uotani Koji,Oda Yoshiaki,Misawa Haruo,Tanaka Masato,Ozaki Toshifumi 대한척추외과학회 2022 Asian Spine Journal Vol.16 No.6

Study Design: This is a virtual three-dimensional (3D) imaging study examining computed tomography (CT) data to investigate instrumentation placement.Purpose: In this study, we aim to clarify the ideal entry point and trajectory of the sacral alar iliac (SAI) screw in relationship to the dorsal foramen at S1 and the respective nerve root.Overview of Literature: To the best of our knowledge, there is yet no detailed 3D imaging study on the ideal entry point of the SAI screw. Despite the evidence suggesting that the dorsal foramen at S1 is a landmark on the sacrum, the S1 nerve root disruption is a general concern during the insertion of SAI screws. No other study has been published examining the nerve root location at the S1and SAI screw insertions.Methods: Preoperative CT data from 26 patients pertaining to adult spinal deformities were investigated in this study. We applied a 3D image processing method for a detailed investigation. Virtual cylinders were used to mimic SAI screws. These were placed to penetrate the sacral iliac joint without violating the other cortex. We then assessed the trajectory of the longest SAI screw and the ideal entry point of SAI using a color mapping method on the surface of the sacrum. We measured the location of the nerve root at S1 in relation to the foramen at S1 and the sacral surface.Results: As per the results of our color mapping, it was determined that areas that received high scores are located medially and caudally to the dorsal foramen of S1. The mean angle between a horizontal line and a line connecting the medial edge of the foramen and nerve root at S1 was 93.5°. The mean distances from the dorsal medial edge of the foramen and sacral surface to S1 nerve root were 21.8 mm and 13.9 mm, respectively.Conclusions: The ideal entry point of the SAI screw is located medially and caudally to the S1 dorsal foramen based on 3D digital mapping. It is also shown that this entry point spares the S1 nerve root from possible iatrogenic injuries.

Present State and Future Trends of Active Power Filters in Japan

Hirofumi Akagi,Noriyuki Watanabe 전력전자학회 1992 ICPE(ISPE)논문집 Vol.1992 No.4

With remarkable development and advance in PWM inverter technology on the basis of fast switching devices in the 1980s, active power filters which are classified into shunt and series active filters have been studied with the focus on their practical installation in industrial power systems. In 1982, a shunt active filter of rating 800kVA was put into practical use for the first time in the world. The main circuit consisted of a current source PWM inverter using GTO thyristors. In 1986, a combined system of a shunt active filter of rating 900kVA and a shunt passive fil­ter of rating 6600kVA was practically installed to suppress the harmonics produced by a large capacity cycloconverter for steel mill drives.<br/> More than one hundred shunt active filters have been operating properly in Japan. The largest one of the shunt active filters is 20MVA, which was developed in 1990 for reactive power and harmonic compensation for an arc fur­nace with the help of a shunt passive filter of 20MVA.<br/> This paper presents a survey of shunt and series active filters using PWM inverters, paying attention to research and practical applications in Japan.<br/>

High Power Matrix Converter for Wind Power Generation Applications

Jun Kang,Noriyuki Takada,Eiji Yamamoto,Eiji Watanabe 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

The matrix converter has many advantages in wind power system applications. Matrix converter is compact and highly efficient because it directly converts generated power from AC generator to AC grid without intermediate DC bus while conventional back-to-back converter systems requires many electrolytic capacitors in DC link bus which are bulky and have short life-time. Matrix converter has both motoring and regenerative power flows keeping low harmonics current in grid. It also can provide reactive power to the grid, which is important characteristic for wind farms to stabilize power system during and after grid failure. In this paper, high power matrix converter is introduced for wind power applications. Major technical features and advantages are described. Experimental results with a PM generator show good feasibility for the wind power applications.

Differences in preoperative planning for high-tibial osteotomy between the standing and supine positions

( Takehiko Matsushita ),( Shu Watanabe ),( Daisuke Araki ),( Kanto Nagai ),( Yuichi Hoshino ),( Noriyuki Kanzaki ),( Tomoyuki Matsumoto ),( Takahiro Niikura ),( Ryosuke Kuroda ) 대한슬관절학회 2021 대한슬관절학회지 Vol.33 No.-

Introduction: Previous studies have reported that alignment changes depend on the patient’s position in orthopedic surgery. However, it has not yet been well examined how the patient’s position affects the preoperative planning in high-tibial osteotomy (HTO). Therefore, the aim of this study was to investigate the effects of the patient’s position on preoperative planning in HTO. Materials and methods: A total of 60 knees in 55 patients who underwent HTO were retrospectively examined. Virtual preoperative planning for medial open-wedge HTO (OWHTO), lateral closed-wedge HTO (CWHTO), and hybrid CWHTO were performed by setting the percentage of the weight-bearing line (%WBL) at 62% as an optimal alignment. The correction angle differences between the supine and standing radiographs were measured. The virtual %WBL (v%WBL) was determined by applying the correction angle obtained from the standing radiograph to the supine radiograph. The %WBL discrepancy (%WBLd) was calculated as v%WBL - 62 (%) to predict the possible correction errors during surgeries. A single regression analysis was performed to examine the correlation between the correction angle difference and %WBLd. Results: The mean correction angle was significantly higher when the preoperative planning was based on standing radiographs than when based on supine radiographs (P < 0.001), and the mean difference was 2.2 ± 1.5°. The difference between the two conditions in the medial opening gaps for OWHTO, lateral wedge sizes (mm) for CWHTO, and hybrid CWHTO were 2.6 ± 2.0, 2.3 ± 1.6, and 1.9 ± 1.4, respectively. The mean v%WBL was 71.2% ± 7.3%, and the mean %WBLd was 10.1% ± 7.4%. A single regression analysis revealed a linear correlation between the correction angle difference and %WBLd (%WBLd = 4.72 × correction angle difference + 0.08). No statistically significant difference in the parameters was found between the supine and standing radiographs postoperatively. Conclusions: We found significant differences in the estimated correction angles between the supine and standing radiographs in the planning for HTO. Therefore, surgeons should carefully consider the difference between supine and standing radiographs and estimate the possible correction error during surgery when planning a HTO.

Antiviral Activity of Peanut (Arachis hypogaea L.) Skin Extract Against Human Influenza Viruses

Juliann Nzembi Makau,Ken Watanabe,Magdy M.D. Mohammed,Noriyuki Nishida 한국식품영양과학회 2018 Journal of medicinal food Vol.21 No.8

The high propensity of influenza viruses to develop resistance to antiviral drugs necessitates the continuing search for new therapeutics. Peanut skins, which are low-value byproducts of the peanut industry, are known to contain high levels of polyphenols. In this study, we investigated the antiviral activity of ethanol extracts of peanut skins against various influenza viruses using cell-based assays. Extracts with a higher polyphenol content exhibited higher antiviral activities, suggesting that the active components are the polyphenols. An extract prepared from roasted peanut skins effectively inhibited the replication of influenza virus A/WSN/33 with a half maximal inhibitory concentration of 1.3 μg/mL. Plaque assay results suggested that the extract inhibits the early replication stages of the influenza virus. It demonstrated activity against both influenza type A and type B viruses. Notably, the extract exhibited a potent activity against a clinical isolate of the 2009 H1N1 pandemic, which had reduced sensitivity to oseltamivir. Moreover, a combination of peanut skin extract with the anti-influenza drugs, oseltamivir and amantadine, synergistically increased their antiviral activity. These data demonstrate the potential application of peanut skin extract in the development of new therapeutic options for influenza management.

Microwave absorption behaviors of polyaniline nanocomposites containing TiO2 nanoparticles

Sook Wai Phang,Masato Tadokoro,Jiro Watanabe,Noriyuki Kuramoto 한국물리학회 2008 Current Applied Physics Vol.8 No.3,4

As nanomaterial possessing moderate conductivity and dielectric property, novel hexanoic acid doped polyaniline (PAni) nanocom-posites containing TiO2 absorption properties of PAni nanocomposites were investigated. The resulted nanorods/tubes in SEM images clearly showed that poly-merization proceeded in micelle/water interface through elongation. The nanocomposites synthesized at 0.C resulted in large number ofnanorods/tubes compared with those synthesized at 25.C. The nanocomposites synthesized at 0.C possess higher permittivity and het-erogeneity, hence will give rise to good microwave absorption property (>99.0% power absorption) in the frequency range of 1013 GHzcompared with 25.C. Among all nanocomposites prepared, PAni/HA/TiO2 with highest permittivity, heterogeneity and loss tangent hasachieved maximum reection loss of 31 dB (>99.9% power absorption) at 10 GHz.

Use of colony-stimulating factor in patients with ovarian cancer receiving paclitaxel and carboplatin in Japan

Kenichi Harano,Akihiro Hirakawa,Takayuki Kato,Keisuke Suzuki,Sachiko Watanabe,Noriyuki Katsumata 대한부인종양학회 2014 Journal of Gynecologic Oncology Vol.25 No.2

Objective: To assess the use of colony-stimulating factors (CSFs) in patients with ovarian cancer who receive adjuvant paclitaxel and carboplatin chemotherapy in clinical practice and to assess whether the frequency of CSF use differs among hospitals in Japan. Methods: CSF use in patients with ovarian cancer who received first-line paclitaxel and carboplatin was analyzed retrospectively using data from the Japanese hospitalization payment system. Results: A total of 1,050 patients at 104 hospitals were identified. The median age was 60 years (range, 22 to 88 years). Of these, 163 patients (15.5%) were diagnosed with neutropenia and 134 patients (12.8%) received CSFs. Among the patients who received CSFs, 125 (93%) received them for the treatment of neutropenia without fever and 1 received them for febrile neutropenia. In total, CSFs were administered for 272 cycles of chemotherapy. Among them, CSFs were used as treatment for neutropenia without fever in 259 cycles (95%), as prophylaxis (primary or secondary) in 12 cycles (4%), and as treatment for febrile neutropenia in 1 cycle. Among hospitals, a median of 4.0% of patients received CSFs with an interquartile range of 25% (Q1, 0%; Q3, 25%). A logistic random effects model showed that the variation in the proportion of patients receiving CSFs among the 104 hospitals was 2.0 (p<0.001), suggesting that the use of CSFs varied across hospitals. Conclusion: Most patients received CSFs for neutropenia without fever. Standardized and evidence-based use of CSFs is critically required among hospitals in Japan.

Giant High-Flow Type Pulmonary Arteriovenous Malformation: Coil Embolization with Flow Control by Balloon Occlusion and an Anchored Detachable Coil

Masayuki Kanematsu,Hiroshi Kondo,Satoshi Goshima,Yusuke Tsuge,Haruo Watanabe,Noriyuki Moriyama 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.1

Pulmonary arteriovenous malformations (PAVMs) are often treated by pushable fibered or non-fibered microcoils, using an anchor or scaffold technique or with an Amplatzer plug through a guiding sheath. When performing percutaneous transcatheter microcoil embolization, there is a risk of coil migration, particularly with high-flow type PAVMs. The authors report on a unique treatment in a patient with a giant high-flow PAVM whose nidus had a maximum diameter of 6 cm. A detachable coil, not detached from a delivery wire (an anchored detachable coil), was first placed in the feeding artery under flow control by balloon occlusion, and then multiple microcoils were packed proximally to the anchored detachable coil. After confirming the stability of the microcoils during a gradual deflation of the balloon, we finally released the first detachable coil. The nidus was reduced in size to 15 mm at one year postoperatively.