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Coronary computed tomography angiographic detection of in-stent restenosis via deep learning reconstruction: a feasibility study. Eur Radiol 2024; 34:2647-2657. [PMID: 37672056 DOI: 10.1007/s00330-023-10110-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/30/2023] [Accepted: 06/25/2023] [Indexed: 09/07/2023]
Abstract
OBJECTIVES Evaluation of in-stent restenosis (ISR), especially for small stents, remains challenging during computed tomography (CT) angiography. We used deep learning reconstruction to quantify stent strut thickness and lumen vessel diameter at the stent and compared it with values obtained using conventional reconstruction strategies. METHODS We examined 166 stents in 85 consecutive patients who underwent CT and invasive coronary angiography (ICA) within 3 months of each other from 2019-2021 after percutaneous coronary intervention with coronary stent placement. The presence of ISR was defined as percent diameter stenosis ≥ 50% on ICA. We compared a super-resolution deep learning reconstruction, Precise IQ Engine (PIQE), and a model-based iterative reconstruction, Forward projected model-based Iterative Reconstruction SoluTion (FIRST). All images were reconstructed using PIQE and FIRST and assessed by two blinded cardiovascular radiographers. RESULTS PIQE had a larger full width at half maximum of the lumen and smaller strut than FIRST. The image quality score in PIQE was higher than that in FIRST (4.2 ± 1.1 versus 2.7 ± 1.2, p < 0.05). In addition, the specificity and accuracy of ISR detection were better in PIQE than in FIRST (p < 0.05 for both), with particularly pronounced differences for stent diameters < 3.0 mm. CONCLUSION PIQE provides superior image quality and diagnostic accuracy for ISR, even with stents measuring < 3.0 mm in diameter. CLINICAL RELEVANCE STATEMENT With improvements in the diagnostic accuracy of in-stent stenosis, CT angiography could become a gatekeeper for ICA in post-stenting cases, obviating ICA in many patients after recent stenting with infrequent ISR and allowing non-invasive ISR detection in the late phase. KEY POINTS • Despite CT technology advancements, evaluating in-stent stenosis severity, especially in small-diameter stents, remains challenging. • Compared with conventional methods, the Precise IQ Engine uses deep learning to improve spatial resolution. • Improved diagnostic accuracy of CT angiography helps avoid invasive coronary angiography after coronary artery stenting.
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Comparison of lung CT number and airway dimension evaluation capabilities of ultra-high-resolution CT, using different scan modes and reconstruction methods including deep learning reconstruction, with those of multi-detector CT in a QIBA phantom study. Eur Radiol 2022; 33:368-379. [PMID: 35841417 DOI: 10.1007/s00330-022-08983-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 06/05/2022] [Accepted: 06/22/2022] [Indexed: 11/04/2022]
Abstract
OBJECTIVE Ultra-high-resolution CT (UHR-CT), which can be applied normal resolution (NR), high-resolution (HR), and super-high-resolution (SHR) modes, has become available as in conjunction with multi-detector CT (MDCT). Moreover, deep learning reconstruction (DLR) method, as well as filtered back projection (FBP), hybrid-type iterative reconstruction (IR), and model-based IR methods, has been clinically used. The purpose of this study was to directly compare lung CT number and airway dimension evaluation capabilities of UHR-CT using different scan modes with those of MDCT with different reconstruction methods as investigated in a lung density and airway phantom design recommended by QIBA. MATERIALS AND METHODS Lung CT number, inner diameter (ID), inner area (IA), and wall thickness (WT) were measured, and mean differences between measured CT number, ID, IA, WT, and standard reference were compared by means of Tukey's HSD test between all UHR-CT data and MDCT reconstructed with FBP as 1.0-mm section thickness. RESULTS For each reconstruction method, mean differences in lung CT numbers and all airway parameters on 0.5-mm and 1-mm section thickness CTs obtained with SHR and HR modes showed significant differences with those obtained with the NR mode on UHR-CT and MDCT (p < 0.05). Moreover, the mean differences on all UHR-CTs obtained with SHR, HR, or NR modes were significantly different from those of 1.0-mm section thickness MDCTs reconstructed with FBP (p < 0.05). CONCLUSION Scan modes and reconstruction methods used for UHR-CT were found to significantly affect lung CT number and airway dimension evaluations as did reconstruction methods used for MDCT. KEY POINTS • Scan and reconstruction methods used for UHR-CT showed significantly higher CT numbers and smaller airway dimension evaluations as did those for MDCT in a QIBA phantom study (p < 0.05). • Mean differences in lung CT number for 0.25-mm, 0.5-mm, and 1.0-mm section thickness CT images obtained with SHR and HR modes were significantly larger than those for CT images at 1.0-mm section thickness obtained with MDCT and reconstructed with FBP (p < 0.05). • Mean differences in inner diameter (ID), inner area (IA), and wall thickness (WT) measured with SHR and HR modes on 0.5- and 1.0-mm section thickness CT images were significantly smaller than those obtained with NR mode on UHR-CT and MDCT (p < 0.05).
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Comparison of traditional two-injection dorsal digital block versus transthecal and subcutaneous single-injection digital block: A systematic review and meta-analysis. HAND SURGERY & REHABILITATION 2021; 40:369-376. [PMID: 33895422 DOI: 10.1016/j.hansur.2021.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/07/2021] [Accepted: 04/14/2021] [Indexed: 10/21/2022]
Abstract
Digital nerve block is a common procedure with several techniques, including the traditional digital nerve block, transthecal digital nerve block, and single subcutaneous palmar digital nerve block. This review aimed to evaluate the efficacy of these three methods. A systematic search was performed in the PubMed, Scopus, and Cochrane Library databases. The risk of bias of the studies was assessed using the Cochrane Collaboration's tool for assessing the risk of bias and the Risk of Bias Assessment Tool for Non-Randomized Studies. Fourteen prospective randomized controlled studies and one prospective comparative study were included. The three methods of digital block showed similar onset times, durations, injection pain and incidence of incomplete anesthesia. This review confirmed that all three methods of digital block are equally effective. Considering that patients prefer a single injection and the potential risk of complications, the single subcutaneous digital block could be more widely used.
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Lumbosacral subdural hematoma associated with cranial subdural hematoma and craniocerebral surgery: Three cases and a systemic literature review. Neurochirurgie 2021; 67:470-478. [PMID: 33450270 DOI: 10.1016/j.neuchi.2020.12.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 11/18/2020] [Accepted: 12/22/2020] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The authors aim to focus on lumbosacral subdural hematoma (SDH) associated with cranial subdural hematoma and craniocerebral surgery, which has been rarely reported. MATERIAL AND METHODS They present 3 cases of lumbosacral SDH, including 2 associated with cranial chronic SDH and 1 following craniotomy for neck clipping of cerebral aneurysm. Using a PubMed search, they also provide a systemic literature review to summarize pathogenesis, treatment and outcome. RESULTS All cases presented with bilateral radiating leg pain, and recovered completely by conservative managements. Predisposing factors were trauma, anticoagulant therapy and brain atrophy. Literature review revealed 54 such cases, in which 28 cases associated with cranial SDH and 26 cases associated with craniocerebral surgery. In both group, main symptoms were low back and radiating leg pain, and sensorimotor deficits. Regardless of treatments, conservatively or surgically, outcome was favorable. Migration of cranial hematoma is most supported pathogenesis, while intracranial hypotension due to cerebrospinal fluid overdrainage procedures may also be a contributing factor for cases associated with craniocerebral surgery. CONCLUSIONS Lumbosacral SDH should be considered in patients present with unexpected low back and radiating leg pains associated with cranial SDH and craniocerebral surgery. Conservative treatment would be reasonable for cases with mild symptoms as the first treatment of choice.
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Crossed cerebellar diaschisis in status epilepticus. Neurochirurgie 2019; 65:425-426. [PMID: 31505193 DOI: 10.1016/j.neuchi.2019.08.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 07/17/2019] [Accepted: 08/18/2019] [Indexed: 11/28/2022]
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[Survey of Recognition, Utilization, and Evaluation for Diagnostic Reference Levels in the Field of X-ray Computed Tomography]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2018; 74:700-707. [PMID: 30033964 DOI: 10.6009/jjrt.2018_jsrt_74.7.700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A survey on recognition, utilization, and evaluation for diagnostic reference levels (DRLs) after establishing Japan DRLs 2015 in the field of X-ray computed tomography (CT) was conducted for members of Japanese Society of Radiological Technology using web-based questionnaire system. The survey consisted of provincial branches to which respondents belong, their occupation, years of professional experience, years of experience in X-ray CT section, recognition of DRLs, and utilization and evaluation of DRLs in the field of X-ray CT section. Each survey item had one to eight questions. A total of 369 members completed the questionnaire. Among them, 295 out of 369 (79.9%) members knew that DRLs were released in Japan. After establishing the DRLs, 226 of 330 (68.5%) and 123 of 319 (38.6%) members investigated the doses used for adult and pediatric CT at their facilities, respectively. Although 345 of 369 (93.5%) members answered that DRLs are necessary for the field of X-ray CT, only 142 of 369 (38.5%) members thought that the established DRLs are enough to use in the field of X-ray CT. The survey has clarified the current status of recognition, utilization, and evaluation for DRLs in the field of X-ray CT after establishing the DRLs in Japan.
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New weighting factor of weighted CTDI equation for PMMA phantom diameter from 8 to 40 cm: A Monte Carlo study. Med Phys 2017; 44:6603-6609. [PMID: 28960375 DOI: 10.1002/mp.12601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 09/17/2017] [Accepted: 09/18/2017] [Indexed: 11/09/2022] Open
Abstract
PURPOSE The weighted computed tomography dose index (CTDIw ) uses measured CTDI values at the center and periphery of a cylindrical phantom. The CTDIw value is calculated using conventional, Bakalyar's, and Choi's weighting factors. However, these weighting factors were produced from only 16- and 32-cm-diameter cylindrical phantoms. This study aims to devise new weighting factors to provide more accurate average dose in the central cross-sectional plane of cylindrical phantoms over a wide range of object diameters, by using Monte Carlo simulations. METHODS Simulations were performed by modeling a Toshiba Aquilion ONE CT scanner, in order to compute the cross-sectional dose profiles of polymethyl methacrylate (PMMA) cylindrical phantoms of each diameter (8-40 cm at 4-cm steps), for various tube voltages and longitudinal beam widths. Two phantom models were simulated, corresponding to the CTDI100 method and the method recommended by American Association of Physicists in Medicine (AAPM) task group 111. The dose-computation PMMA cylinders of 1 mm diameter were located between the phantom surfaces and the centers at intervals of 1 mm, from which cross-sectional dose profiles were calculated. By using linear least-squares fits to the obtained cross-sectional dose profiles data, we determined new weighting factors to estimate more accurate average doses in the PMMA cylindrical phantoms by using the CTDIw equation: CTDIw = Wcenter ・ CTDIcenter + Wperiphery ・ CTDIperiphery . In order to demonstrate the validity of the devised new weighting factors, the percentage difference between average dose and CTDIw value was evaluated for the weighting factors (conventional, Bakalyar's, Choi's, and devised new weighting factors) in each calculated cross-sectional dose profile. RESULTS With the use of linear least-squares techniques, new weighting factors (Wcenter = 3/8 and Wperiphery = 5/8 where Wcenter and Wperiphery are weighting factors for CTDIcenter and CTDIperiphery ) were determined. The maximum percentage differences between average dose and CTDIw value were 16, -12, -8, and -6% for the conventional, Bakalyar's, Choi's, and devised new weighting factors, respectively. CONCLUSIONS We devised new weighting factors (Wcenter = 3/8 and Wperiphery = 5/8) to provide more accurate average dose estimation in PMMA cylindrical phantoms over a wide range of diameter. The CTDIw equation with devised new weighting factors could estimate average dose in PMMA cylindrical phantoms with a maximum difference of -6%. The results of this study can estimate the average dose in PMMA cylindrical phantoms more accurately than the conventional weighting factors (Wcenter = 1/3 and Wperiphery = 2/3).
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Influence of 320-detector-row volume scanning and AAPM report 111 CT dosimetry metrics on size-specific dose estimate: a Monte Carlo study. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2016; 39:697-703. [PMID: 27444155 DOI: 10.1007/s13246-016-0465-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 07/12/2016] [Indexed: 12/26/2022]
Abstract
The American Association of Physicists in Medicine (AAPM) task group 204 has recommended the use of size-dependent conversion factors to calculate size-specific dose estimate (SSDE) values from volume computed tomography dose index (CTDIvol) values. However, these conversion factors do not consider the effects of 320-detector-row volume computed tomography (CT) examinations or the new CT dosimetry metrics proposed by AAPM task group 111. This study aims to investigate the influence of these examinations and metrics on the conversion factors reported by AAPM task group 204, using Monte Carlo simulations. Simulations were performed modelling a Toshiba Aquilion ONE CT scanner, in order to compute dose values in water for cylindrical phantoms with 8-40-cm diameters at 2-cm intervals for each scanning parameter (tube voltage, bow-tie filter, longitudinal beam width). Then, the conversion factors were obtained by applying exponential regression analysis between the dose values for a given phantom diameter and the phantom diameter combined with various scanning parameters. The conversion factors for each scanning method (helical, axial, or volume scanning) and CT dosimetry method (i.e., the CTDI100 method or the AAPM task group 111 method) were in agreement with those reported by AAPM task group 204, within a percentage error of 14.2 % for phantom diameters ≥11.2 cm. The results obtained in this study indicate that the conversion factors previously presented by AAPM task group 204 can be used to provide appropriate SSDE values for 320-detector-row volume CT examinations and the CT dosimetry metrics proposed by the AAPM task group 111.
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Hand hygiene: dreams come true “Clean Care is Safer Care”. Antimicrob Resist Infect Control 2015. [PMCID: PMC4612335 DOI: 10.1186/2047-2994-4-s1-p150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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The most effective influence of 17-(3-ethoxypropyl) substituent on the binding affinity and the agonistic activity in KNT-127 derivatives, δ opioid receptor agonists. Bioorg Med Chem 2013; 21:7628-47. [PMID: 24262888 DOI: 10.1016/j.bmc.2013.10.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 10/21/2013] [Accepted: 10/22/2013] [Indexed: 10/26/2022]
Abstract
We investigated the structure-activity relationship of KNT-127 (opioid δ agonist) derivatives with various 17-substituents which are different in length and size. The 17-substituent in KNT-127 derivatives exerted a great influence on the affinity and agonistic activity for the δ receptor. While the compounds with electron-donating 17-substituents showed higher affinities for the δ receptor than those with electron-withdrawing groups, KNT-127 derivatives with 17-fluoroalkyl groups (the high electron-withdrawing groups) showed high selectivities for the δ receptor among evaluated compounds. In addition, the basicity of nitrogen as well as the structure of the 17-N substituent such as the length and configuration at an asymmetric carbon atom contributed to agonist properties for the δ receptor. Thus, the analog with a 17-(3-ethoxypropyl) group showed the best selectively and potent agonistic activity for the δ receptor among KNT-127 derivatives. These findings should be useful for designing novel δ selective agonists.
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Potential of a Saccharomyces cerevisiae recombinant strain lacking ethanol and glycerol biosynthesis pathways in efficient anaerobic bioproduction. Bioengineered 2013; 5:123-8. [PMID: 24247205 DOI: 10.4161/bioe.26569] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Saccharomyces cerevisiae shows high growth activity under low pH conditions and can be used for producing acidic chemicals such as organic acids as well as fuel ethanol. However, ethanol can also be a problematic by-product in the production of chemicals except for ethanol. We have reported that a stable low-ethanol production phenotype was achieved by disrupting 6 NADH-dependent alcohol dehydrogenase genes of S. cerevisiae. Moreover, the genes encoding the NADH-dependent glycerol biosynthesis enzymes were further disrupted because the ADH-disrupted recombinant strain showed high glycerol production to maintain intracellular redox balance. The recombinant strain incapable producing ethanol and glycerol could have the potential to be a host for producing metabolite(s) whose biosynthesis is coupled with NADH oxidation. Indeed, we successfully achieved almost 100% yield for L-lactate production using this recombinant strain as a host. In addition, the potential of our constructed recombinant strain for efficient bioproduction, particularly under anaerobic conditions, is also discussed.
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Stable disruption of ethanol production by deletion of the genes encoding alcohol dehydrogenase isozymes in Saccharomyces cerevisiae. J Biosci Bioeng 2012; 113:192-5. [DOI: 10.1016/j.jbiosc.2011.09.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 09/15/2011] [Accepted: 09/24/2011] [Indexed: 11/29/2022]
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Synthesis of quinolinomorphinan-4-ol derivatives as δ opioid receptor agonists. Bioorg Med Chem 2012; 20:949-61. [DOI: 10.1016/j.bmc.2011.11.047] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 11/22/2011] [Accepted: 11/22/2011] [Indexed: 11/29/2022]
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Evaluation of small-intestinal abnormalities in adult patients with Henoch-Schönlein purpura using video capsule. Endoscopy 2011; 43 Suppl 2 UCTN:E162-3. [PMID: 21563063 DOI: 10.1055/s-0030-1256266] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Comprehensive phenotypic analysis of single-gene deletion and overexpression strains of Saccharomyces cerevisiae. Yeast 2011; 28:349-61. [PMID: 21341307 DOI: 10.1002/yea.1843] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 01/02/2011] [Indexed: 11/11/2022] Open
Abstract
We quantified the growth behaviour of all available single-gene deletion and overexpression strains of budding yeast. Genome-wide analyses enabled the extraction of the genes and identification of the functional categories for which genetic perturbation caused the change of growth behaviour. Statistical analyses revealed defective growth for 646 deletion and 1302 overexpression strains. We classified these deleted and overexpressed genes into known functional categories, and identified several functional categories having fragility and robustness for cellular growth. We also screened the deletion and overexpression strains that exhibited a significantly higher growth rate than the strain without genetic perturbation, and found that three deletion and two overexpression strains were high-growth strains. The genes and functional categories identified in the analysis might provide useful information on designing industrially useful yeast strains.
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[Evaluation of 320-row area detector computed tomography (ADCT) coronary angiography for patients with atrial fibrillation]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2011; 67:321-327. [PMID: 21532241 DOI: 10.6009/jjrt.67.321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The aim of this study was to evaluate 320-row area detector CT (ADCT) for patients with atrial fibrillation (Af) based on simulated exposure using electrocardiogram RR intervals and comparison with the findings of coronary CT angiography (CCTA) using 64-row multi slice CT (MSCT). The probability of including RR intervals of 900 ms or more was calculated when the acquisition time was varied from 1 to 4 beats. Overall, 51 patients with Af who underwent CCTA were examined. The exposure time for CCTA, the total dose length product (DLP) for the examination, and the image quality (scored 0 to 3: poor to excellent) were compared between ADCT and MSCT. The probability of including RR intervals of 900 ms or more was highly significantly increased at 3 beats of acquisition time. The exposure time using ADCT was reduced by 75% compared with MSCT (ADCT/MSCT: 2.8/11.3 s), and the total DLP was reduced by 40% (ADCT/MSCT: 1398/2277 mGy·cm). Moreover, ADCT provided diagnosable images in all cases, and the mean image quality score for ADCT was significantly higher than that for MSCT (ADCT/MSCT: 2.8/2.4). Thus, 320-row ADCT at 3 beats of acquisition time can provide CCTA images of acceptable quality for patients with Af.
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Comparison of robot-assisted and manual retinal vessel microcannulation in an animal model. Br J Ophthalmol 2010; 95:731-4. [DOI: 10.1136/bjo.2010.193391] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Synthesis of pyrrolomorphinan derivatives as κ opioid agonists. Bioorg Med Chem Lett 2010; 20:5035-8. [DOI: 10.1016/j.bmcl.2010.07.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2010] [Revised: 07/08/2010] [Accepted: 07/09/2010] [Indexed: 11/27/2022]
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[Current status of the "Organization for X-ray Computed Tomography Technological Specialist"]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2008; 64:719-720. [PMID: 18648162 DOI: 10.6009/jjrt.64.719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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[Automatic selection of optimal cardiac-phase in coronary CT angiography--its clinical usefulness for patients with atrial fibrillation]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2008; 64:442-449. [PMID: 18451601 DOI: 10.6009/jjrt.64.442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The optimal cardiac phases for coronary CT angiography (CTA) are end-systole and mid-diastole, in which cardiac movement is slow. In conventional methods, these cardiac phases are determined by visual selection. We have compared the images in the optimal cardiac phases that were selected by the conventional method and cardiac-phase search software (Phase Navi), and examined the clinical usefulness of Phase Navi in patients with atrial fibrillation. The subjects were 38 patients (regular rhythm: 20, atrial fibrillation: 18). The continuity scores of patients with regular rhythm (Phase Navi, conventional methods) were 2.4+/-0.3-2.5+/-0.3 in end-systole and 2.4+/-0.5-2.4+/-0.4 in mid-diastole. The scores of patients with atrial fibrillation (Phase Navi, conventional methods) were 2.3+/-0.4-2.3+/-0.4 in end-systole, and 2.2+/-0.5-2.1+/-0.6 in mid-diastole. Because the continuity scores of the optimal images from Phase Navi were similar to those from the conventional method, Phase Navi had clinical usefulness in patients with atrial fibrillation.
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Parasagittal Arachnoid Markings on the Inner Skull on Three-Dimensional CT: Relation between Hydrocephalus and Arachnoid Granules. Neuroradiol J 2007; 20:259-64. [DOI: 10.1177/197140090702000301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2007] [Accepted: 04/22/2007] [Indexed: 11/17/2022] Open
Abstract
The purpose of the study was to evaluate the number and size of arachnoid markings on the inner plate of the skull on 3D-CT. The subjects included 16 hydrocephalus and 26 non-hydrocephalus cases. We evaluated the correlation between age and both the number and sizes of the arachnoid markings, and compared them between hydrocephalus and non-hydrocephalus cases. We also evaluated cases exhibiting a “smooth cranium” that had no arachnoid markings at all on the inner plate. There was a positive correlation between age and the number of the arachnoid markings. There were no statistically significant differences in arachnoid markings between hydrocephalus and non-hydrocephalus cases, while, there were statistically significant differences in the frequency of “smooth cranium” findings in the population under ten years old. The “smooth cranium” can only be seen in hydrocephalus cases. These findings may be a clue to the morphological or functional changes of the arachnoid villi in hydrocephalus cases.
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Catalytic Aerobic Oxidation of nor-Binaltorphimine (nor-BNI) Analogs without 4,5-Epoxy Bridge Affords a More Selective Ligand for .KAPPA. Opioid Receptor than the Representative .KAPPA. Antagonist nor-BNI. Chem Pharm Bull (Tokyo) 2007; 55:1489-93. [DOI: 10.1248/cpb.55.1489] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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[Multi slice CT (MSCT)]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2006; 64 Suppl 7:313-8. [PMID: 17461165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
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Convenient Synthesis of Oxazolidinones by the Use of Halomethyloxirane, Primary Amine, and Carbonate Salt. J Org Chem 2005; 70:5737-40. [PMID: 15989363 DOI: 10.1021/jo0501644] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Primary amines reacted with carbonate salts (Na2CO3, K2CO3, Cs2CO3, and Ag2CO3) and halomethyloxiranes in the presence of a base such as DBU or TEA to give oxazolidinones in high yields. The use of K2CO3 among these carbonate gave the best yield in this synthesis. A reaction mechanism was proposed that the oxazolidinone was obtained from an oxazinanone intermediate via a bicyclo[2.2.1] intermediate. The present reaction can be widely applied to convenient synthesis of useful N-substituted oxazolidinones and chiral oxazolidinones.
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[Evaluation of time resolution in cardiac synchronized image reconstruction using multi-slice CT]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2005; 61:409-18. [PMID: 15815560 DOI: 10.6009/jjrt.kj00003326702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
One of the newest CT application technologies is cardiac synchronized image reconstruction. In this technology, evaluation of time-resolution is very important. We developed a method of measuring time-resolution in cardiac synchronized reconstruction, and evaluated various scanning protocols. In our experiment, ECG-gated scanning was done by multi-slice CT (Aquilion16 Super Heart Edition, Toshiba Medical Systems Co., Ltd., Japan). The nominal slice thickness was 0.5 mm, and rotation time was 0.5 sec. Input heart rate was set at 40, 45, 50, 55, 60, 70, 75, 80, and 90 bpm, and helical pitch at 3.2, 4.0, and 4.8 (beam-pitch: 0.200, 0.250 and 0.300). We measured FWTM of the obtained sensitivity distribution and compared at each scanning protocol. Time resolution improved as helical pitch decreased and heart rate increased. However, phase-time resolution deteriorated as heart rate increased. The results of our experiment indicated that a segment center was determined by X-ray tube rotation time and heart rate, and the number of segments was determined by heart rate, helical pitch, and reconstruction position. Time resolution changed with X-ray tube rotation time, heart rate, helical pitch, and reconstruction position. In this report, we provide a reference for an optimal scanning protocol in cardiac synchronized image reconstruction.
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Abstract
Although the principal dosimetric quantity in computed tomography (CT) can be assessed using a pencil ionization chamber with an active length of 100 mm, standard CT dosimetry phantoms of polymethylmethacrylate (PMMA) , and plates of aluminum, most facilities do not possess the requisites. We present a practical method of estimating CTDI(100, c), CTDI(100, p) and the half-value layer (HVL) from CTDI(100, air), which is measured parallel with the axis of rotation of the scanner to free-in-air. The three data chosen for this method of estimation were as follows: 1) the relation of HVL to CTDI(100, air) per radiographic exposure (mAs); 2) the relation of HVL to CTDI(100, c) per CTDI(100, air); 3) the relation of HVL to CTDI(100, p) per CTDI(100, air). The data were based on the measured values of six CT scanners, so as to avoid dependence on the technical characteristics of a specific manufacturer. The estimated value has a possible maximum uncertainty of 20%, although this method of estimation is practical for dose assessment.
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Investigations of Polymyxin B−Phospholipid Interactions by Vibrational Sum Frequency Generation Spectroscopy. J Phys Chem B 2004. [DOI: 10.1021/jp0404347] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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[Special issue: evaluation on blood flow]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2004; 59:1451. [PMID: 15001857 DOI: 10.6009/jjrt.kj00000921673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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[The improvement in the cerebral blood flow analysis software in case of CT-perfusion inspection and the examination of the scan protocol]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2004; 59:1568-72. [PMID: 15001873 DOI: 10.6009/jjrt.kj00000921689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In our hospital, CT-perfusion was introduced in April, 2002. It is used to diagnose, to determine what treatment to use and to prognosticate cerebral blood flow after operation in super acute period brain infarct. At the beginning of the introduction, processing time and dosage for partial areas needed improvement. Therefore, we investigated the possibility of shorter processing time and lower dosage of radiation with the help of improvement in the analysis software as well as a different scan method. Two methods of reducing radiation dosage were examined. (1) The speed of X-ray rotation was slowed down; while photon per image was maintained, total mAs was lowered. (2) Continuation scan was replaced by intermission one. Analyzing time with older and newer version of analysis software was compared. The dosage was able to decrease by 25% as a result of the rotation speed slowed down; it became further less by 50% with the intermission scan. Processing such as the vein extraction was automated by using new analysis software and successfully shorten the analysing time without damaging the reliability of analyses. We forecast that more clinical research on further lowering dosage and stabilization of analyzing will enable us to provide better information.
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[Visualization of coronary artery stents by MSCT at 0.5-mm slice thickness]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2004; 60:278-85. [PMID: 15054317 DOI: 10.6009/jjrt.kj00000922296] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Coronary artery visualization by multi-slice CT and the evaluation of coronary stenosis were examined. Multi-slice CT could not be used for evaluation after the coronary artery stent custody method. We examined various coronary artery stent custody phantoms and stent visualization of clinical examples by using multi-slice CT with a slice thickness of 0.5 mm. ECG-gated scanning was done by inputting ECG using 4DAS (Data Acquisition System) multi-slice CT with a slice thickness of 0.5 mm. We carried out image reconstruction, measured the CT number, and examined the inside stent. The CT number of the inside stent rose in accordance with stent diameter. The inside stent was visualized clearly at 0.5 mm in comparison with 1.0 mm in slice thickness. Visualization of the lumen was influenced in the Stent Custody Phantom by the quality of the stent material, Strut form, and the size of the diameter. The inside stent could be evaluated with the S670 4 mmphi stent. Form evaluation of the inside stent was possible, although the cavity in the stent was influenced by the difference in distance between peaks.
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Interaction of peptides derived from RecA with single-stranded oligonucleotides containing 5-formyl-2'-deoxyuridine. NUCLEIC ACIDS SYMPOSIUM SERIES 2003:41-2. [PMID: 12903258 DOI: 10.1093/nass/44.1.41] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We report the first example of chemical cross-linking of 5-formyl-2'-deoxyuridine containing oligonucleotides with oligopeptides through a Schiff base formation. Twenty amino acid residue peptides investigated here were derived from the DNA binding site of RecA protein. We have demonstrated that the lysine residue placed at the 6th or 8th position from the N-terminus of the peptide directly contacts with DNA.
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[The up-to-date vascular imaging technology using multislice CT]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2003; 59:322-8. [PMID: 12785327 DOI: 10.6009/jjrt.kj00000921758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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37
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[Actual CT inspection (2): the directions of contrast media, and window setting]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2002; 58:1644-52. [PMID: 12577025 DOI: 10.6009/jjrt.kj00000921544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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38
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Abstract
The purpose of this study was to examine (a) the incidence of leftward bias for paired organs (hand, foot, eye, and ear) in India (n = 418) and Japan (n = 697), and (b) the incidence of accident amongst individuals with leftward, rightward, and no bias across countries. The impetus for the study was obtained from a speculation that individuals with leftward bias commit more accidents than their counterparts. Data were collected with the help of a questionnaire on side bias, along with a check-list on accidents (included in the questionnaire). Results showed that participants from these two countries did not differ in terms of leftwardness for any of these forms of side bias. Left-handers were found to commit more accidents in India but not in Japan. Reanalysis of data in terms of left-, mixed-, and right-handedness indicated that mixed handers committed more accidents than extreme (left- + right-) handers in Japan but not in India.
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Abstract
BACKGROUND To evaluate the effect of carotid endarterectomy on ophthalmic artery flow direction and peak systolic flow velocity, the authors examined the ophthalmic artery on 32 patients who had undergone carotid endarterectomy. METHODS The 32 patients had more than 70% stenosis of the internal carotid artery at its origin on angiography. The ophthalmic artery ipsilateral to the carotid endarterectomy was evaluated by the ophthalmic artery color Doppler flow imaging before surgery and then at one week, one month, and three months after surgery. FINDINGS (1) Before carotid endarterectomy: eight patients showed reversed ophthalmic artery direction. In the other 24 patients with antegrade ophthalmic artery flow direction, the average peak systolic flow velocity was 0.17+/-0.10 m/sec. (2) At one week after carotid endarterectomy: The reversed ophthalmic artery flow direction was resolved in each patient. The average peak systolic flow velocity in the patients with preoperative antegrade flow rose significantly to 0.28+/-0.10 m/sec (p<0.05). (3) At one month and three months after carotid endarterectomy: All patients showed the antegrade ophthalmic artery flow direction. The average peak systolic flow velocities showed no significant change compared to the value at one week after carotid endarterectomy. (4) During the followed up period, there was no patient showing worsening or recurrence of clinical symptoms including the visual symptoms. INTERPRETATION Carotid endarterectomy brought about the correction of the reversed flow and an increase in the peak systolic flow velocity of the ipsilateral ophthalmic artery immediately after surgery.
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Human cystine/glutamate transporter: cDNA cloning and upregulation by oxidative stress in glioma cells. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1512:335-44. [PMID: 11406111 DOI: 10.1016/s0005-2736(01)00338-8] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A human cDNA for amino acid transport system x(C)(-) was isolated from diethyl maleate-treated human glioma U87 cells. U87 cells expressed two variants of system x(C)(-) transporters hxCTa and hxCTb with altered C-terminus regions probably generated by the alternative splicing at 3'-ends. Both hxCTa and hxCTb messages were also detected in spinal cord, brain and pancreas, although the level of hxCTb expression appears to be lower than that of hxCTa in these tissues. When expressed in Xenopus oocytes, hxCTb required the heavy chain of 4F2 cell surface antigen (4F2hc) and exhibited the Na(+)-independent transport of L-cystine and L-glutamate, consistent with the properties of system x(C)(-). In agreement with this, 137 kDa band was detected by either anti-xCT or anti-4F2hc antibodies in the non-reducing condition in western blots, whereas it shifted to 50 kDa or 90 kDa bands in the reducing condition, indicating the association of two proteins via disulfide bands. We found that the expression of xCT was rapidly induced in U87 cells upon oxidative stress by diethyl maleate treatment, which was accompanied by the increase in the L-cystine uptake by U87 cells. Because of this highly regulated nature, xCT in glial cells would fulfill the task to protect neurons against oxidative stress by providing suitable amount of cystine to produce glutathione.
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Chemical cross-linking of peptides derived from RecA with single-stranded oligonucleotides containing 5-formyl-2'-deoxyuridine. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2001; 20:1079-83. [PMID: 11562961 DOI: 10.1081/ncn-100002494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We report the first example of chemical cross-linking of 5-formyl-2'-deoxyuridine containing oligonucleotides with oligopeptides through a Schiff base formation. Twenty amino acid residue peptides investigated here were derived from the DNA binding site of RecA protein. We have demonstrated that the lysine residue placed at the 6th or 8th position from the N-terminus of the peptide directly contacts with DNA.
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42
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Construction of a computed tomographic phantom for a Japanese male adult and dose calculation system. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2001; 40:69-75. [PMID: 11357713 DOI: 10.1007/s004110000082] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Computational human phantoms have been widely used to estimate organ doses and other dosimetric quantities related to the human body where direct measurements are difficult to perform. In recent years, voxel phantoms (voxel = volume element) based on computed tomographic (CT) data of real persons have been constructed which provide a realistic description of the human anatomy. A CT phantom of a Japanese male adult with an average body size was developed as the first Asian voxel phantom. The segmented phantom consists of more than 100 regions enabling the calculation of doses for various parts of the body. The bone marrow distribution was precisely modelled according to the CT values. The EGS4 Monte Carlo transport code was combined with the phantom to calculate organ doses for external exposure due to photons and electrons up to 1 TeV. The calculated organ doses were compared with respective data using MIRD-type mathematical phantoms. In some cases, significant discrepancies in doses were observed, demonstrating the necessity of sophisticated models for accurate dose calculations.
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[A case of high flow CCF with congestive hemorrhage]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2000; 28:647-51. [PMID: 10920827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The authors report a case of high flow CCF with intracerebral hemorrhage during treatment with endovascular coil embolization. A 52-year-old woman had been in good health until a sudden onset of orbital bruit and left orbital tinnitus occurred. Conjunctival chemosis and diplopia caused by left abducens palsy gradually progressed. Left internal carotid arteriography revealed a carotid-cavernous sinus fistula with direct high-flow shunt. The fistula drained into the superior orbital vein, inferior petrosal sinus, intercavernous sinus and sphenoparietal sinus with significant cortical reflux. The attempt at transarterial balloon occlusion failed. Then transvenous coil embolization was performed. During the course of endovascular treatment, follow up CT depicted intracerebral hemorrhage. Intracerebral hemorrhage was asymptomatic and thought to be caused by venous hypertension from cortical reflux. The patient underwent direct occlusion of the left sphenoparietal sinus for prevention of further hemorrhage via craniotomy. Lastly, the cavernous sinus was completely occluded by transvenous coil embolization. The signs and symptoms resolved 3 months after the procedures.
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Induction of apoptosis and anti-HIV activity by tannin- and lignin-related substances. BASIC LIFE SCIENCES 2000; 66:595-611. [PMID: 10800465 DOI: 10.1007/978-1-4615-4139-4_33] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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45
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Interaction between hydroquinone and ascorbic acid derivatives: quenching effect of organic solvents. Anticancer Res 2000; 20:1577-81. [PMID: 10928073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The interaction between hydroquinone (HQ) and ascorbic acid analogs was investigated. Semiquinone radicals (SQ.) generated by HQ were comparably scavenged by ascorbic acid, sodium ascorbate and ascorbate 6-palmitate, but much less efficiently by ascorbate 2,6-dipalmitate. Organic solvents, such as dimethysulfoxide (DMSO) or ethanol, which are utilized for solubilization of water-insoluble analogs, ascorbate 6-palmitate and ascorbate 2,6-dipalmitate, also scavenged SQ.. DMSO scavenged the SQ. more efficiently than ethanol. This suggests the importance of considering such a quenching effect of organic solvent in the study of the interaction between HQ and antioxidants. The involvement of the ascorbate radical for cytotoxicity induction is discussed.
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Antimicrobial and radical modulation activity of AV-07, a poly-herbal formula. In Vivo 2000; 14:351-5. [PMID: 10836209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
An extract of AV-07 was investigated for various biological activities. Pretreatment of mice with the AV-07 extract significantly protected them from lethal infection with E. coli. ESR spectroscopy showed that the extract produced radicals under alkaline conditions and enhanced the radical intensity of sodium ascorbate, suggesting its pro-oxidant action at higher concentrations. The extract effectively scavenged superoxide anion, produced by hypoxanthine-xanthine oxidase reaction and hydroxyl radical, produced by Fenton reaction. These data demonstrate that AV-07 extract contains various bioactive substances, suggesting its medicinal efficacy.
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Interaction between antioxidants and hydroquinone/bisphenol. Anticancer Res 1999; 19:5457-62. [PMID: 10697577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
We have investigated the stability of semiquinone radical (SQ .) produced from the mixture of hydroquinone (HQ) and bisphenol A (BPA) in the presence of various antioxidants, some of which induce apoptosis in tumor cell lines. BPA produced no detectable amount of ESR signal. The acceleration of HQ oxidation by BPA results in the production of SQ .. The BPA-enhanced SQ . production may occur through either SQ. regeneration by electron transfer from BPA working as an antioxidant or the O2- scavenging activity of BPA. SQ . intensity of HQ/BPA was reduced by lower concentrations of sodium ascorbate, epigallocatechin, gallate and quercetin, but significantly enhanced by gallic acid. The initial SQ . was replaced by the radicals of antioxidants except lignin and salicylic acid, at higher concentrations, due to their radical-radical coupling or dismutation process. Among these compounds, gallic acid enhanced the radical intensity of SQ . to the greatest extent. The results suggest that antioxidants from foods suppress the activity of xenobiotics such as HQ, however, they produce their own radical at higher concentrations, suggesting their bimodal actions. The present study demonstrates the usefulness of ESR spectroscopy for the interaction between HQ/BPA and antioxidants.
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[Brain surface clear cell ependymoma: case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 1999; 27:843-6. [PMID: 10478346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We report a case of brain surface clear cell ependymoma. A 13-year-old boy presented with complaints of right hypesthesia. Computed tomography and magnetic resonance image showed a left fronto-parietal cystic, calcified mass lesion. He underwent total resection of the tumor including cyst wall. The tumor located on the surface of the parietal lobe was sharply demarcated from the surrounding brain tissue and there was no continuity with the ventricular wall. Histological examination of the surgical specimens showed oligodendroglioma-like cells that had round unclei, clear cytoplasm which formed perivascular pseudorosettes, and immunoreactivity for glial fibrillary acidic protein (GFAP). Electromicroscopically, microvilli were seen. The findings were compatible with clear cell ependymoma. The cyst wall was lined with a layer of single cuboidal cells and, immunohistochemically, had no basal membrane. The inner surface of the cyst was positive for EMA, and the cuboidal cells were positive for GFAP. We discuss possible mechanisms for tumor growth in our case and the histogenesis of its cyst.
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Radical intensity and cytotoxicity of butylated hydroxyanisole and its orthobisphenol dimer. Anticancer Res 1999; 19:3947-52. [PMID: 10628336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The radical intensity of BHA (4-Hydroxy-3-t-butylanisole) and its dimer (3,3'-Di-t-butyl-5,5'-dimethoxy-1,1'-biphenyl-2,2'-diol, Bis-BHA) were compared with their cytotoxic activity. ESR spectroscopy showed that BHA produced characteristic five peaks of radicals under alkaline conditions (pH > 9.5). At higher pH, BHA radical rapidly disappeared, and progressively transformed into new radical species, as detected by the splitting of the ESR signal. BHA showed higher cytotoxic activity against salivary gland tumor cell line than against normal human gingival fibroblast. On the other hand, Bis-BHA did not produce any detectable amounts of radicals at wide ranges of pH, corresponding with its weaker cytotoxic activity as compared with BHA. BHA scavenged DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical and superoxide anion, more efficiently than Bis-BHA. The present study demonstrated that BHA is more cytotoxic, produces higher amounts of radicals and more efficiently scavenges various radical species, as compared with Bis-BHA. This suggests the possible link between the cytotoxic activity and radical generation/scavenging activity in BHA-derived compounds.
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Interaction between sodium ascorbate and polyphenols. Anticancer Res 1999; 19:4177-86. [PMID: 10628372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The interaction between sodium ascorbate and polyphenols was investigated by two different parameters: radical intensity and cytotoxicity induction. ESR spectroscopy shows that sodium ascorbate, lignins (alkali-lignin, lignin sulfonate, pine cone-derived lignin) and tannins (gallic acid, epigallocatechin gallate (EGCg), tannic acid) all produced radicals with different intensities under alkaline conditions. All lignin samples significantly enhanced the radical intensity and cytotoxic activity of sodium ascorbate, whereas all tannin samples slightly reduced the radical intensity of sodium ascorbate. Sodium ascorbate efficiently scavenged the radical and cytotoxic activity of gallic acid, as expected by the ionization potential and heat of reaction by the PM3 semiempirical method. EGCg and tannic acid slightly reduced the cytotoxic activity of sodium ascorbate. The present study demonstrates that lignins and tannins modify the radical intensity and cytotoxic activity of sodium ascorbate in different manners, and suggests the applicability of ESR spectroscopy for the screening of drug to drug interaction.
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