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author:("Ito, junii")
1.  Eye movement-related brain activity during perceptual and cognitive processing 
PMCID: PMC4006019  PMID: 24795577
eye movements; saccade; smooth pursuit; eye tracking; free viewing; EEG; local field potentials; fMRI
2.  Preliminary analysis of risk factors for late rectal toxicity after helical tomotherapy for prostate cancer 
Journal of Radiation Research  2013;54(5):919-924.
The purpose of this study is to examine risk factors for late rectal toxicity for localized prostate cancer patients treated with helical tomotherapy (HT). The patient cohort of this retrospective study was composed of 241 patients treated with HT and followed up regularly. Toxicity levels were scored according to the Radiation Therapy Oncology Group grading scale. The clinical and dosimetric potential factors increasing the risk of late rectal toxicity, such as age, diabetes, anticoagulants, prior abdominal surgery, prescribed dose, maximum dose of the rectum, and the percentage of the rectum covered by 70 Gy (V70), 60 Gy (V60), 40 Gy (V40) and 20 Gy (V20) were compared between ≤ Grade 1 and ≥ Grade 2 toxicity groups using the Student's t-test. Multivariable logistic regression analysis of the factors that appeared to be associated with the risk of late rectal toxicity (as determined by the Student's t-test) was performed. The median follow-up time was 35 months. Late Grade 2–3 rectal toxicity was observed in 18 patients (7.4%). Age, the maximum dose of the rectum, V70 and V60 of the ≥ Grade 2 toxicity group were significantly higher than in those of the ≤ Grade 1 toxicity group (P = 0.00093, 0.048, 0.0030 and 0.0021, respectively). No factor was significant in the multivariable analysis. The result of this study indicates that the risk of late rectal toxicity correlates with the rectal volume exposed to high doses of HT for localized prostate cancer. Further follow-up and data accumulation may establish dose–volume modeling to predict rectal complications after HT.
PMCID: PMC3766297  PMID: 23525159
prostate cancer; helical tomotherapy; late toxicity; intensity-modulated radiation therapy; image-guided radiation therapy
3.  Cross-frequency interaction of the eye-movement related LFP signals in V1 of freely viewing monkeys 
Recent studies have emphasized the functional role of neuronal activity underlying oscillatory local field potential (LFP) signals during visual processing in natural conditions. While functionally relevant components in multiple frequency bands have been reported, little is known about whether and how these components interact with each other across the dominant frequency bands. We examined this phenomenon in LFP signals obtained from the primary visual cortex of monkeys performing voluntary saccadic eye movements (EMs) on still images of natural-scenes. We identified saccade-related changes in respect to power and phase in four dominant frequency bands: delta-theta (2–4 Hz), alpha-beta (10–13 Hz), low-gamma (20–40 Hz), and high-gamma (>100 Hz). The phase of the delta-theta band component is found to be entrained to the rhythm of the repetitive saccades, while an increment in the power of the alpha-beta and low-gamma bands were locked to the onset of saccades. The degree of the power modulation in these frequency bands is positively correlated with the degree of the phase-locking of the delta-theta oscillations to EMs. These results suggest the presence of cross-frequency interactions in the form of phase-amplitude coupling (PAC) between slow (delta-theta) and faster (alpha-beta and low gamma) oscillations. As shown previously, spikes evoked by visual fixations during free viewing are phase-locked to the fast oscillations. Thus, signals of different types and at different temporal scales are nested to each other during natural viewing. Such cross-frequency interaction may provide a general mechanism to coordinate sensory processing on a fast time scale and motor behavior on a slower time scale during active sensing.
PMCID: PMC3572441  PMID: 23420631
local field potential; oscillation; saccade; natural vision; cross-frequency coupling
5.  Saccade-Related Modulations of Neuronal Excitability Support Synchrony of Visually Elicited Spikes 
Cerebral Cortex (New York, NY)  2011;21(11):2482-2497.
During natural vision, primates perform frequent saccadic eye movements, allowing only a narrow time window for processing the visual information at each location. Individual neurons may contribute only with a few spikes to the visual processing during each fixation, suggesting precise spike timing as a relevant mechanism for information processing. We recently found in V1 of monkeys freely viewing natural images, that fixation-related spike synchronization occurs at the early phase of the rate response after fixation-onset, suggesting a specific role of the first response spikes in V1. Here, we show that there are strong local field potential (LFP) modulations locked to the onset of saccades, which continue into the successive fixation periods. Visually induced spikes, in particular the first spikes after the onset of a fixation, are locked to a specific epoch of the LFP modulation. We suggest that the modulation of neural excitability, which is reflected by the saccade-related LFP changes, serves as a corollary signal enabling precise timing of spikes in V1 and thereby providing a mechanism for spike synchronization.
PMCID: PMC3183421  PMID: 21459839
free viewing; local field potential; phase locking; primary visual cortex; spike synchrony
6.  Display of both N- and C-terminal target fusion proteins on the Aspergillus oryzae cell surface using a chitin-binding module 
A novel cell surface display system in Aspergillus oryzae was established by using a chitin-binding module (CBM) from Saccharomyces cerevisiae as an anchor protein. CBM was fused to the N or C terminus of green fluorescent protein (GFP) and the fusion proteins (GFP-CBM and CBM-GFP) were expressed using A. oryzae as a host. Western blotting and fluorescence microscopy analysis showed that both GFP-CBM and CBM-GFP were successfully expressed on the cell surface. In addition, cell surface display of triacylglycerol lipase from A. oryzae (tglA), while retaining its activity, was also successfully demonstrated using CBM as an anchor protein. The activity of tglA was significantly higher when tglA was fused to the C terminus than N terminus of CBM. Together, these results show that CBM used as a first anchor protein enables the fusion of both the N and/or C terminus of a target protein.
PMCID: PMC2903697  PMID: 20499230
Cell surface display; Aspergillus oryzae; Chitin-binding module; Triacylglycerol lipase
7.  Regulation of the Display Ratio of Enzymes on the Saccharomyces cerevisiae Cell Surface by the Immunoglobulin G and Cellulosomal Enzyme Binding Domains▿  
Applied and Environmental Microbiology  2009;75(12):4149-4154.
We constructed a novel cell surface display system to control the ratio of target proteins on the Saccharomyces cerevisiae cell surface, using two pairs of protein-protein interactions. One protein pair is the Z domain of protein A derived from Staphylococcus aureus and the Fc domain of human immunoglobulin G. The other is the cohesin (Coh) and dockerin (Dock) from the cellulosome of Clostridium cellulovorans. In this proposed displaying system, the scaffolding proteins (fusion proteins of Z and Coh) were displayed on the cell surface by fusing with the 3′ half of α-agglutinin, and the target proteins fused with Fc or Dock were secreted. As a target protein, a recombinant Trichoderma reesei endoglucanase II (EGII) was secreted into the medium and immediately displayed on the yeast cell surface via the Z and Fc domains. Display of EGII on the cell surface was confirmed by hydrolysis of β-glucan as a substrate, and EGII activity was detected in the cell pellet fraction. Finally, two enzymes, EGII and Aspergillus aculeatus β-glucosidase 1, were codisplayed on the cell surface via Z-Fc and Dock-Coh interactions, respectively. As a result, the yeast displaying two enzymes hydrolyzed β-glucan to glucose very well. These results strongly indicated that the proposed strategy, the simultaneous display of two enzymes on the yeast cell surface, was accomplished by quantitatively controlling the display system using affinity binding.
PMCID: PMC2698344  PMID: 19411409
8.  Inadvertent C2–C3 Union After C1–C2 Posterior Fusion in Adults 
European Spine Journal  2005;15(3):270-277.
Introduction: Some authors pointed out that there were more than a few patients with inadvertent C2–C3 union after C1–C2 posterior fusion, although few detailed studies of C2–C3 union have been reported. The purpose of this study was to clarify whether C2–C3 union accelerated adjacent C3–C4 disc degeneration after C1–C2 posterior fusion and to investigate the related factors for C2–C3 union. Methods: Sixteen patients with rheumatoid arthritis (RA group) (4 males, 12 females, mean age 60 years, mean follow-up period 4 years and 3 months) and fifteen patients without RA (non-RA group) (11 males, 4 females, mean 52 years, mean follow-up period 3 years and 10 months) who underwent C1–C2 posterior fusion were radiologically assessed. The C2–C3 union was defined as trabecular bone formation at C2–C3 interlamina in lateral radiograph. C3–C4 disc height was measured to evaluate the disc degeneration. Results: C2–C3 union rate was 56% and 60% in RA group and non-RA group, respectively. In RA group, postoperative C3–C4 disc height was lower (Student’s t-test, P = 0.029) and the decrease rate of C3–C4 disc height was higher (Student’s t-test, P = 0.015) in patients with C2–C3 union than in patients without C2–C3 union. In non-RA group, the age at operation was older (Student’s t-test, P = 0.0007), and the C1–C2 fusion angle (Student’s t-test, P = 0.012) was smaller in patients with C2–C3 union than in patients without C2–C3 union. Conclusions: C2–C3 union after C1–C2 posterior fusion occurred in more than half of both groups. Inadvertent C2–C3 union should be considered a radiological complication and a potential risk factor due to acceleration of C3–C4 disc degeneration in RA.
PMCID: PMC3489302  PMID: 15940474
Atlanto-axial subluxation; Disc degeneration; Posterior fusion; Rheumatoid arthritis; Union
9.  Synergistic Saccharification, and Direct Fermentation to Ethanol, of Amorphous Cellulose by Use of an Engineered Yeast Strain Codisplaying Three Types of Cellulolytic Enzyme 
A whole-cell biocatalyst with the ability to induce synergistic and sequential cellulose-degradation reaction was constructed through codisplay of three types of cellulolytic enzyme on the cell surface of the yeast Saccharomyces cerevisiae. When a cell surface display system based on α-agglutinin was used, Trichoderma reesei endoglucanase II and cellobiohydrolase II and Aspergillus aculeatus β-glucosidase 1 were simultaneously codisplayed as individual fusion proteins with the C-terminal-half region of α-agglutinin. Codisplay of the three enzymes on the cell surface was confirmed by observation of immunofluorescence-labeled cells with a fluorescence microscope. A yeast strain codisplaying endoglucanase II and cellobiohydrolase II showed significantly higher hydrolytic activity with amorphous cellulose (phosphoric acid-swollen cellulose) than one displaying only endoglucanase II, and its main product was cellobiose; codisplay of β-glucosidase 1, endoglucanase II, and cellobiohydrolase II enabled the yeast strain to directly produce ethanol from the amorphous cellulose (which a yeast strain codisplaying β-glucosidase 1 and endoglucanase II could not), with a yield of approximately 3 g per liter from 10 g per liter within 40 h. The yield (in grams of ethanol produced per gram of carbohydrate consumed) was 0.45 g/g, which corresponds to 88.5% of the theoretical yield. This indicates that simultaneous and synergistic saccharification and fermentation of amorphous cellulose to ethanol can be efficiently accomplished using a yeast strain codisplaying the three cellulolytic enzymes.
PMCID: PMC348929  PMID: 14766607

Results 1-9 (9)