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Takashima H, Suzuki A, Waseda K, Saka Y, Kurita A, Ando H, Maeda K, Sakurai S, Nishikawa Y, Amano T. TCT-39 Diagnostic ability of contrast medium induced fractional flow reserve to assess functional lesion severity of coronary artery stenosis. J Am Coll Cardiol 2015. [DOI: 10.1016/j.jacc.2015.08.086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Takashima H, Waseda K, Gosho M, Kurita A, Ando H, Sakurai S, Maeda K, Kumagai S, Suzuki A, Amano T. Severity of morphological lesion complexity affects fractional flow reserve in intermediate coronary stenosis. J Cardiol 2015; 66:239-45. [DOI: 10.1016/j.jjcc.2014.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 11/01/2014] [Accepted: 11/06/2014] [Indexed: 10/24/2022]
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Sakurai S, Takashima H, Waseda K, Gosho M, Kurita A, Ando H, Maeda K, Suzuki A, Fujimoto M, Amano T. Influence of plaque characteristics on fractional flow reserve for coronary lesions with intermediate to obstructive stenosis: insights from integrated-backscatter intravascular ultrasound analysis. Int J Cardiovasc Imaging 2015; 31:1295-301. [PMID: 26129657 DOI: 10.1007/s10554-015-0699-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 06/26/2015] [Indexed: 01/01/2023]
Abstract
The aim of this study was to determine the correlation between the fractional flow reserve (FFR) values and volumetric intravascular ultrasound (IVUS) parameters derived from classic gray-scale IVUS and integrated backscatter (IB)-IVUS, taking into account known confounding factors. Patients with unstable angina pectoris with the frequent development of vulnerable plaques often showed the discrepancy between the FFR value and the quantitative coronary angiography findings. Our target population was 107 consecutive subjects with 114 isolated lesions who were scheduled for elective coronary angiography. The FFR was calculated as the mean distal coronary pressure divided by the mean aortic pressure during maximal hyperemia. Various volumetric parameters such as lipid plaque volume (LPV) and percentage of LPV (%LPV) were measured using IB-IVUS. Simple and multivariate linear regression analysis was employed to evaluate the correlation between FFR values and various classic gray-scale IVUS and IB-IVUS parameters. The Akaike information criterion (AIC) was used to compare the goodness of fit in an each model. Both the %LPV (r = -0.24; p = 0.01) and LPV (r = -0.40; p < 0.01) were significantly correlated with the FFR value. Only the LPV (AIC = -147.0; p = 0.006) and %LPV (AIC = -152.9; p = 0.005) proved to be independent predictors for the FFR value even after the adjustment of known confounding factors. The volumetric assessment by IB-IVUS could provide better information in terms of the relationship between plaque morphology and the FFR values as compared to the classic IVUS 2-dimensional gray-scale analysis.
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Waseda K, Takashima H, Fujimoto M, Kuroda Y, Kosaka T, Kurita A, Ando H, Maeda K, Sakurai S, Suzuki A, Amano T. CRT-160 Influence of Stent Length on Stent Deliverability between First and Second Generation Drug-Eluting Stent Platform Using Bench Test Model. JACC Cardiovasc Interv 2015. [DOI: 10.1016/j.jcin.2014.12.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Nakajima I, Aoki J, Sakurai S, Naitoh H, Taketomi-Takahashi A, Tsushima Y. Local massive venous invasion in colorectal cancer: CT-pathological correlation and its clinical implication. Br J Radiol 2015; 88:20140319. [PMID: 25353693 PMCID: PMC4277374 DOI: 10.1259/bjr.20140319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 10/18/2014] [Accepted: 10/28/2014] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To identify CT findings of massive venous invasion (MVI) in colorectal cancer, compare them to pathological findings and evaluate its clinical implications. METHODS Among 423 patients who received surgical resection of colorectal cancer, pre-operative CT of 26 patients (15 males, 11 females; mean age, 63.0 ± 12.1 years) with histopathologially proven MVI and 26 patients (14 males, 12 females; mean age, 71.1 ± 9.6 years) with histopathologically proven lymph node (LN) metastases were reviewed and compared with histopathological findings. We evaluated CT detectability of MVI and the morphologic differences between MVI and LN metastasis. All cases were followed up for at least 6 months after surgery. RESULTS Pre-operative CT correctly diagnosed only one case as tumour thrombus. 9 lesions were not detected on CT, and others were misdiagnosed pre-operatively as regional LN metastasis (14 cases) and juxtatumoural abscess (2 cases). After reviewing these cases, MVIs were identifiable in 20 of 26 cases. MVI was depicted on CT as nodules (oval, lobulated), abscess-like or intravenous tumour thrombus. MVI was significantly larger than LN metastasis (p < 0.05), while contrast enhancement was significantly lower (p < 0.05), and MVI often had an enhanced rim. Ten patients had synchronous metastases, and six patients had metachronous distant metastases within 5 years. CONCLUSION Many cases of MVI were distinguishable from LN metastases on pre-operative CT of colorectal cancer, but their appearances were varied, reflecting their histopathological behaviours. The distant metastatic rate was much higher in cases with MVI. ADVANCES IN KNOWLEDGE Radiologists should be aware of CT findings of MVI in colorectal cancer as a sentinel sign of distant metastasis.
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Fujiwara K, Takahashi T, Nguyen P, Kubota Y, Gamou S, Sakurai S, Takahashi S. Uptake and retention of radio-caesium in earthworms cultured in soil contaminated by the Fukushima nuclear power plant accident. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2015; 139:135-139. [PMID: 25464049 DOI: 10.1016/j.jenvrad.2014.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 03/19/2014] [Accepted: 10/16/2014] [Indexed: 06/04/2023]
Abstract
To understand the effects of radionuclides on non-human biota and the environment, it is essential to study the intake and metabolism of radio-isotopes in earthworms which are among the most important soil organisms, and Eisenia fetida, which were used in this study, are known to be sufficiently sensitive to chemicals and representative of common earthworms. In this study, we assessed the concentration ratios, uptake and retention, absorbed dose rate, and distribution of radio-caesium in earthworms. The concentration ratios of (137)Cs (i.e., the concentrations of radio-caesium in earthworms relative to those in dry soil) were higher early in the culturing period and decreased gradually over the experimental period. (137)Cs taken up by E. fetida was cleared rapidly after the worms were cultured in radio-caesium-free soil, suggesting that the metabolism of radio-caesium in earthworms is very rapid. Autoradiography demonstrated that the concentration of radio-caesium within the digestive tract was as high as that in the soil, while radio-caesium in the body tissue was lower than radio-caesium in the soil and was almost uniformly distributed among earthworm tissues. The highest absorbed dose rate of total exposure to radio-caesium ((137)Cs + (134)Cs) was calculated to be 1.9 × 10(3) (μGy/day) in the earthworms.
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Morioka A, Sato S, Ochiai K, Sakasai A, Hori J, Yamauchi M, Nishitani T, Kaminaga A, Masaki K, Sakurai S, Hayashi T, Matsukawa M, Tamai H, Ishida S. Neutron Tranamission Experiment of Boron-doped Resin for the JT-60SC Neutron Shield using 2.45 Mev Neutron Source. J NUCL SCI TECHNOL 2014. [DOI: 10.1080/00223131.2004.10875657] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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58
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Takashima H, Sakurai S, Waseda K, Kurita A, Ando H, Kumagai S, Amano T. Very late acquired peri-stent contrast staining and incomplete stent apposition with biodegradable polymer stents: insight from optical coherence tomography. Int J Cardiol 2014; 176:e11-2. [PMID: 25085382 DOI: 10.1016/j.ijcard.2014.06.101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/29/2014] [Indexed: 10/25/2022]
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59
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Makishima K, Enoto T, Hiraga JS, Nakano T, Nakazawa K, Sakurai S, Sasano M, Murakami H. Possible evidence for free precession of a strongly magnetized neutron star in the magnetar 4U 0142+61. PHYSICAL REVIEW LETTERS 2014; 112:171102. [PMID: 24836230 DOI: 10.1103/physrevlett.112.171102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Indexed: 06/03/2023]
Abstract
Magnetars are a special type of neutron stars, considered to have extreme dipole magnetic fields reaching ∼ 10(11) T. The magnetar 4 U 0142+61, one of the prototypes of this class, was studied in broadband x rays (0.5-70 keV) with the Suzaku observatory. In hard x rays (15-40 keV), its 8.69 sec pulsations suffered slow phase modulations by ± 0.7 sec, with a period of ∼ 15 h. When this effect is interpreted as free precession of the neutron star, the object is inferred to deviate from spherical symmetry by ∼ 1.6 × 10(-4) in its moments of inertia. This deformation, when ascribed to magnetic pressure, suggests a strong toroidal magnetic field, ∼ 10(12) T, residing inside the object. This provides one of the first observational approaches towards toroidal magnetic fields of magnetars.
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Kato D, Takashima H, Waseda K, Kurita A, Kuroda Y, Kosaka T, Kuhara Y, Ando H, Maeda K, Kumagai S, Sakurai S, Suzuki A, Toda Y, Watanabe A, Sato S, Fujimoto M, Mizuno T, Amano T. Feasibility and safety of intracoronary nicorandil infusion as a novel hyperemic agent for fractional flow reserve measurements. Heart Vessels 2014; 30:477-83. [PMID: 24748047 DOI: 10.1007/s00380-014-0508-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 03/28/2014] [Indexed: 02/08/2023]
Abstract
Fractional flow reserve (FFR) is a useful modality to assess the functional significance of coronary stenoses. Although adenosine triphosphate (ATP) is generally used as the hyperemic stimulus, we sometimes encounter adverse events like hypotension during FFR measurement. Nicorandil, an ATP-sensitive potassium channel opener, recognized as an epicardial and resistance vessel dilator, has not been fully evaluated as a possible alternative hyperemic agent. The aim of this study was to evaluate the feasibility and safety of intracoronary nicorandil infusion compared to intravenous ATP for FFR measurement in patients with coronary artery disease. A total of 102 patients with 124 intermediate lesions (diameter stenosis >40 and <70% by visual assessment) were enrolled. All vessels underwent FFR measurements with both ATP (150 μg/kg/min) and nicorandil (2.0 mg) stimulus. FFR, hemodynamic values, and periprocedural adverse events between the two groups were evaluated. A strong correlation was observed between FFR with ATP and FFR with nicorandil (r = 0.954, p < 0.001). The agreement between the two sets of measurements was also high, with a mean difference of 0.01 ± 0.03. The mean aortic pressure drop during pharmacological stimulus was significantly larger with ATP compared to nicorandil (9.6 ± 9.6 vs. 5.5 ± 5.8 mmHg, p < 0.001). During FFR measurement, transient atrioventricular block was frequently observed with ATP compared to nicorandil (4.0 vs. 0%, p = 0.024). This study suggests that intracoronary nicorandil infusion is associated with clinical utility and safety compared to ATP as an alternative hyperemic agent for FFR measurement.
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Maeda K, Waseda K, Takashima H, Fujimoto M, Kuroda Y, Kosaka T, Kurita A, Ando H, Kumagai S, Sakurai S, Kato D, Suzuki A, Sato S, Mizuno T, Amano T. TCTAP A-084 Impact of Pre-dilatation Strategy on Vessel Response Following Stent Implantation in Patients with De Novo Coronary Artery Lesion. J Am Coll Cardiol 2014. [DOI: 10.1016/j.jacc.2014.02.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Omoto T, Aoki A, Maruta K, Sakurai S, Iizuka H, Kawaura H. Severity score for mitral valve repair in active stage infective endocarditis. Thorac Cardiovasc Surg 2014. [DOI: 10.1055/s-0034-1367403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sakurai S, Takashima H, Waseda K, Ando H, Kurita A, Amano T. Multiple recanalized images of thrombotic occlusion 19 years after percutaneous coronary intervention: insights from optical coherence tomography and intravascular ultrasound. Int J Cardiol 2014; 172:480-1. [PMID: 24491858 DOI: 10.1016/j.ijcard.2014.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/28/2013] [Accepted: 01/01/2014] [Indexed: 11/27/2022]
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Eguchi E, Tanigawa T, Takahashi M, Sakurai S, Maruyama K. Association between subjective sleepiness and severity of sleep-disordered breathing among truck drivers in Japan. Sleep Med 2013. [DOI: 10.1016/j.sleep.2013.11.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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65
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Maruyama K, Tanigawa T, Eguchi E, Sakurai S, Saito I. Underreport of energy intake modified the association between sleep disturbance and overweight among middle-aged japanese: toon health study. Sleep Med 2013. [DOI: 10.1016/j.sleep.2013.11.476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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66
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Takashima H, Kurita A, Toda Y, Watanabe A, Waseda K, Kosaka T, Ando H, Sakurai S, Kato D, Amano T. Impact of right atrial pressure as venous pressure on fractional flow reserve calculation in patients with hemodialysis. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p3970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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67
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Shibanuma K, Arai T, Hasegawa K, Hoshi R, Kamiya K, Kawashima H, Kubo H, Masaki K, Saeki H, Sakurai S, Sakata S, Sakasai A, Sawai H, Shibama Y, Tsuchiya K, Tsukao N, Yagyu J, Yoshida K, Kamada Y, Mizumaki S, Hayakawa A, Takigami H, Barabaschi P, Davis S, Peyrot M, Phillips G. Assembly study for JT-60SA tokamak. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2012.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Shibama Y, Masaki K, Sakurai S, Shibanuma K, Sakasai A, Oonawa T, Araki T, Asano S. Welding technology R&D on port joint of JT-60SA vacuum vessel. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2013.01.100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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69
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Sakurai S, Watanabe H, Takahara A. Preparation and characterization of looped polydimethylsiloxane brushes. Polym J 2013. [DOI: 10.1038/pj.2013.69] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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70
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Takashima H, Kurita A, Waseda K, Ando H, Kosaka T, Maeda K, Sakurai S, Kato D, Mizuno T, Amano T. Association between clustering of lesion morphology and functional ischemia of intermediate coronary stenosis in patients with stable angina pectoris. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.2865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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71
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Fujimoto M, Waseda K, Takashima H, Maeda K, Asai K, Kuroda Y, Kosaka T, Kurita A, Kuhara Y, Ando H, Sakurai S, Kato D, Suzuki A, Nakano Y, Niwa T, Mukai K, Sato S, Mizuno T, Amano T. Effect of Oral Hydration on Renal Function After Coronary Catheterization. Am J Cardiol 2013. [DOI: 10.1016/j.amjcard.2013.01.225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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72
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Takashima H, Kurita A, Waseda K, Mizuno T, Asai K, Kuroda Y, Kosaka T, Kuhara Y, Ando H, Maeda K, Ito Y, Sakurai S, Kato D, Niwa T, Nakano Y, Mukai K, Sato S, Fujimoto M, Amano T. THE ASSOCIATION BETWEEN LESION LOCATION AND FUNCTIONAL SIGNIFICANCE OF INTERMEDIATE CORONARY LESIONS. J Am Coll Cardiol 2013. [DOI: 10.1016/s0735-1097(13)61770-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Kawamoto N, Fukao T, Kaneko H, Hirayama K, Sakurai S, Arai T, Kondo M, Kawamoto M, Matsui E, Teramoto T, Kasahara K, Bai C, Zhang G, Omoya K, Matsukuma E, Morimoto M, Suzuki H, Aoki Y, Kimura T, Nada M, Morita H, Tokumi T, Takemura M, Seishima M, Shiraki M, Iwasa S, Kondo N. Risk factors for infantile atopic dermatitis and recurrent wheezing. J Investig Allergol Clin Immunol 2012; 22:116-125. [PMID: 22533234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
BACKGROUND The pathogenic mechanisms of atopic dermatitis (AD) and recurrent wheezing (RW) during infancy are not fully understood. OBJECTIVE We evaluated immunological markers associated with AD and RW during infancy. METHODS We followed a cohort (n = 314) from birth to 14 months of age. Some of the participants underwent a physical examination and blood test at 6 and 14 months of age. Univariate and multivariate logistic regression analysis and receiver operating characteristic curve analysis were performed to find which immunological markers could be risk factors for AD and RW. RESULTS Of 16 immunological markers found in cord blood, only immunoglobulin (Ig) E was associated with AD at 6 months of age (adjusted OR [aOR], 1.607). None of the markers was associated with AD or RW at 14 months of age. Of 23 immunological markers at 6 months of age, total IgE (aOR, 1.018) and sensitization to egg white (aOR, 23.246) were associated with AD at 14 months of age. Phytohemagglutinin (PHA)-induced production of interleukin (IL) 4 from peripheral blood mononuclear cells (PBMCs) (aOR, 1.043) was associated with RW at 14 months of age. CONCLUSION Cord blood IgE was a risk factor for AD at 6 months of age. Total IgE and sensitization to egg white at 6 months of age were risk factors for AD at 14 months of age. PHA-induced IL-4 production in PBMCs at 6 months of age was a risk factor for RW at 14 months of age.
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Tanigawa T, Muraki I, Yamagishi K, Sakurai S, Ohira T, Imano H, Kitamura A, Kiyama M, Sato S, Iso H. P2-302 Nocturnal intermittent hypoxia and cardiovascular risk factors in community-dwelling Japanese: the Circulatory Risk in Communities Study (CIRCS). Br J Soc Med 2011. [DOI: 10.1136/jech.2011.142976k.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Sakaguchi S, Takeuchi Y, Yamasaki M, Sakurai S, Isagi Y. Lineage admixture during postglacial range expansion is responsible for the increased gene diversity of Kalopanax septemlobus in a recently colonised territory. Heredity (Edinb) 2011; 107:338-48. [PMID: 21427749 DOI: 10.1038/hdy.2011.20] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We aimed to reveal the effects of range expansion and subsequent lineage admixture from separated glacial refugia on genetic diversity of Kalopanax septemlobus in Japan, by combining nuclear microsatellite data and ecological niche modelling. Allelic richness and gene diversity were compared at the population and regional level. We also statistically examined these indices as a function of population accessibility to the last glacial maximum (LGM) palaeodistribution reconstructed by ecological niche modelling to test a simple range expansion scenario from glacial refugia. Genetic diversity was highest in the populations of southern Japan and gradually decreased towards the north. However, an additional centre of genetic diversity, when measured as gene diversity, was found in northern Honshu Island, where distinct lineages were shown to be in contact. Positive effects of population accessibility to the LGM range were detected in both diversity indices at different spatial scales. The combined data support independent postglacial range expansions towards the north from the edge populations on the exposed coastal shelf of Pacific and Sea of Japan in northern Honshu during the LGM, which subsequently resulted in markedly low genetic diversity in the northernmost extant range, Hokkaido. The regional increase in gene diversity in northern Honshu is likely to be the result of postglacial lineage admixture. Relative difference in the spatial scales best relating population genetic diversity with the LGM distribution can be explained by a higher rate of allelic richness diversity loss during range expansions and stronger effects of lineage admixture on gene diversity.
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