136 research outputs found

    Chronic irradiation with low-dose-rate ¹³⁷Cs-γ rays inhibits NGF-induced neurite extension of PC12 cells via Ca²⁺/calmodulin-dependent kinase II activation

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    Chronic irradiation with low-dose-rate ¹³⁷Cs-γ rays inhibits the differentiation of human neural progenitor cells and influences the expression of proteins associated with several cellular functions. We aimed to determine whether such chronic irradiation influences the expression of proteins associated with PC12 cells. Chronic irradiation at 0.027 mGy/min resulted in inhibition of NGF-induced neurite extension. Furthermore, irradiation enhanced the nerve growth factor (NGF)-induced increase in the phosphorylation of extracellular signal–regulated kinase (ERK), but did not affect the phosphorylation of NGF receptors, suggesting that irradiation influences pathways unassociated with the activation of ERK. We then examined whether irradiation influenced the Akt−Rac1 pathway, which is unaffected by ERK activation. Chronic irradiation also enhanced the NGF-induced increase in Akt phosphorylation, but markedly inhibited the NGF-induced increase in Rac1 activity that is associated with neurite extension. These results suggest that the inhibitory effect of irradiation on neurite extension influences pathways unassociated with Akt activation. As Ca²⁺ /calmodulin-dependent kinase II (CaMKII) is known to inhibit the NGF-induced neurite extension in PC12 cells, independent of ERK and Akt activation, we next examined the effects of irradiation on CaMKII activation. Chronic irradiation induced CaMKII activation, while application of KN-62 (a specific inhibitor of CaMKII), attenuated increases in CaMKII activation and recovered neurite extension and NGF-induced increases in Rac1 activity that was inhibited by irradiation. Our results suggest that chronic irradiation with low-dose-rate γ-rays inhibits Rac1 activity via CaMKII activation, thereby inhibiting NGF-induced neurite extension

    A Novel Modification of the Retrograde Approach for the Recanalization of Chronic Total Occlusion of the Coronary Arteries Intravascular Ultrasound-Guided Reverse Controlled Antegrade and Retrograde Tracking

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    ObjectivesThe study evaluates the feasibility and efficacy of the novel modification of the retrograde recanalization of the chronic total occlusion (CTO) of the coronary arteries by using intravascular ultrasound (IVUS)-guided reverse controlled antegrade and retrograde tracking (CART).BackgroundDespite improvement in the techniques and materials, CTO recanalization is still suboptimal. The CART procedure has improved success rates, but there are certain inherent technical uncertainties and risk with this procedure.MethodsThis first series involves 31 patients, with 22 patients having previous failed attempts at CTO recanalization. All patients were treated with bilateral approach and using IVUS-guided reverse CART concept.ResultsSuccessful recanalization of the CTO was achieved in all cases (100%). The access route was septal collateral in 20 (70%) cases and epicardial collateral in 11 (30%) cases. IVUS guidance was used successfully in 30 cases, and the channel dilator (microcatheter) was used in 27 cases. Guidewire injury and grade 1 perforation was seen in 3 (9%) cases, which were managed conservatively. There was no death, coronary artery bypass surgery, or pericardiocentesis in this group of patients. Mean fluoroscopy time was 65.84 ± 23.16 min, ranging from 31 to 106 min and total contrast volume used 321.32 ± 137.77 ml (range 115 to 650 ml).ConclusionsThis first series describes a high success rate of CTO recanalization with IVUS-guided reverse CART in selected patients performed by an experienced operator

    Hydrogen Isotope (H2 and D2) Sorption Study of CHA-Type Zeolites

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    Using either single H2 and D2 or H2-D2 mixed gases, the sorption abilities of CHA (chabazite)-type zeolites ion-exchanged with K, Na, or Ca were studied at 77, 201, and 250 K. The LTA (Linde Type A) (3A) and FAU (faujasite)-type zeolites were also examined for comparison. The pore diameters in these materials were found to decrease on the order of FAU > Ca-CHA > [K-CHA, Na-CHA, and LTA(3A)]. The quantities of D2 adsorbed on these zeolites were larger than the amounts of H2. At higher temperatures, the CHA-type zeolites having smaller pores exhibited superior D2/H2 selectivity compared with the LTA(3A) and FAU, suggesting that hydrogen isotope separation using zeolites is affected by pore size

    Different Patterns of Vascular Response Between Patients With or Without Diabetes Mellitus After Drug-Eluting Stent Implantation Optical Coherence Tomographic Analysis

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    ObjectivesWe performed this study to investigate with optical coherence tomography (OCT) the vascular response after sirolimus-eluting stent (SES) implantation between patients with and those without diabetes mellitus (DM).BackgroundThe difference in vascular response after SES implantation between patients with and those without DM has not been fully evaluated with OCT.MethodsOptical coherence tomography was performed to examine 74 nonrestenotic SES implanted in 63 patients (32 with DM and 31 without DM) at 9 months after SES implantation. For struts showing neointimal coverage, the neointimal thickness on the luminal side of each strut section was measured, and neointimal characteristics were classified into high, low, and layered signal pattern.ResultsBaseline patient characteristics and lesion and procedural characteristics data were similar between the 2 groups. In total, 11,422 struts were analyzed. High signal neointima was observed in 90.2 ± 13.9%, low signal neointima in 7.3 ± 10.0%, and layered neointima in 2.7 ± 5.8%/stents. There was higher incidence of low signal neointima (10.5 ± 10.3% vs. 4.5 ± 5.6%, p = 0.003), neointimal thickness was larger (median: 106.8 μm, interquartile range: 79.3 to 130.4 μm vs. median: 83.5 μm, interquartile range: 62.3 to 89.3 μm; p < 0.0001), and neointimal coverage of stent struts was higher (92.1 ± 6.2% vs. 87.2 ± 11.9%; p = 0.03) in DM patients.ConclusionsHigh signal neointimal pattern was predominantly observed, and low or layered signal pattern was observed in some cases. In DM patients, low signal neointima was observed with high frequency. Neointimal coverage and neointimal thickness was also higher in DM patients as compared with non-DM patients

    The Role of Optical Coherence Tomography in Coronary Intervention

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    Optical coherence tomography (OCT) is an optical analog of intravascular ultrasound (IVUS) that can be used to examine the coronary arteries and has 10-fold higher resolution than IVUS. Based on polarization properties, OCT can differentiate tissue characteristics (fibrous, calcified, or lipid-rich plaque) and identify thin-cap fibroatheroma. Because of the strong attenuation of light by blood, OCT systems required the removal of blood during OCT examinations. A recently developed frequency-domain OCT system has a faster frame rate and pullback speed, making the OCT procedure more user-friendly and not requiring proximal balloon occlusion. During percutaneous coronary intervention (PCI), OCT can provide detailed information (dissection, tissue prolapse, thrombi, and incomplete stent apposition [ISA]). At follow-up examinations after stent implantation, stent strut coverage and ISA can be assessed. Several OCT studies have demonstrated delayed neointimal coverage following drug-eluting stent (DES) implantation vs. bare metal stent (BMS) placement. While newer DESs promote more favorable vascular healing, the clinical implications remain unknown. Recent OCT studies have provided insights into restenotic tissue characteristics; DES restenotic morphologies differ from those with BMSs. OCT is a novel, promising imaging modality; with more in-depth assessments of its use, it may impact clinical outcomes in patients with symptomatic coronary artery disease

    The Efficacy of a Bilateral Approach for Treating Lesions With Chronic Total Occlusions The CART (Controlled Antegrade and Retrograde subintimal Tracking) Registry

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    ObjectivesThe aim of this study was to evaluate the safety and feasibility of a new concept for chronic total occlusion (CTO) recanalization—using a bilateral approach that utilizes a Controlled Antegrade and Retrograde subintimal Tracking (CART) technique.BackgroundSuccessful percutaneous recanalization of coronary CTOs results in improved long-term outcomes. The recanalization of CTOs in native coronary arteries no doubt represents one of the most technically challenging of interventional procedures.MethodsA total of 224 consecutive patients (mean age 61 ± 9 years; 86.2% men) were enrolled in this prospective multicenter registry. This technique combines the simultaneous use of antegrade and retrograde approaches. A subintimal dissection is created in both antegrade and retrograde fashion, thereby limiting the extension of the subintimal dissection within the CTO portion.ResultsOf 224 CTO lesions (>3 months in duration) undergoing attempted recanalization using the CART technique, 145 cases (64.7%) had undergone previous CTO recanalization attempts. The success rates of crossing in a retrograde fashion with a wire and a balloon were 87.9% and 79.9%, respectively. The overall technical and procedural success rates achieved in this registry were 92.4% and 90.6%, respectively.ConclusionsA bilateral approach for CTO lesions using the CART technique is feasible, safe, and has a higher success rate than previous approaches. These results indicate that a bilateral technique can solve a major dilemma that commonly affects CTO procedures

    Nuclear β-catenin and CD44 upregulation characterize invasive cell populations in non-aggressive MCF-7 breast cancer cells

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    <p>Abstract</p> <p>Background</p> <p>In breast cancer cells, the metastatic cell state is strongly correlated to epithelial-to-mesenchymal transition (EMT) and the CD44<sup>+</sup>/CD24<sup>- </sup>stem cell phenotype. However, the MCF-7 cell line, which has a luminal epithelial-like phenotype and lacks a CD44<sup>+</sup>/CD24<sup>- </sup>subpopulation, has rare cell populations with higher Matrigel invasive ability. Thus, what are the potentially important differences between invasive and non-invasive breast cancer cells, and are the differences related to EMT or CD44/CD24 expression?</p> <p>Methods</p> <p>Throughout the sequential selection process using Matrigel, we obtained MCF-7-14 cells of opposite migratory and invasive capabilities from MCF-7 cells. Comparative analysis of epithelial and mesenchymal marker expression was performed between parental MCF-7, selected MCF-7-14, and aggressive mesenchymal MDA-MB-231 cells. Furthermore, using microarray expression profiles of these cells, we selected differentially expressed genes for their invasive potential, and performed pathway and network analysis to identify a set of interesting genes, which were evaluated by RT-PCR, flow cytometry or function-blocking antibody treatment.</p> <p>Results</p> <p>MCF-7-14 cells had enhanced migratory and invasive ability compared with MCF-7 cells. Although MCF-7-14 cells, similar to MCF-7 cells, expressed E-cadherin but neither vimentin nor fibronectin, β-catenin was expressed not only on the cell membrane but also in the nucleus. Furthermore, using gene expression profiles of MCF-7, MCF-7-14 and MDA-MB-231 cells, we demonstrated that MCF-7-14 cells have alterations in signaling pathways regulating cell migration and identified a set of genes (<it>PIK3R1</it>, <it>SOCS2</it>, <it>BMP7</it>, <it>CD44 </it>and <it>CD24</it>). Interestingly, MCF-7-14 and its invasive clone CL6 cells displayed increased CD44 expression and downregulated CD24 expression compared with MCF-7 cells. Anti-CD44 antibody treatment significantly decreased cell migration and invasion in both MCF-7-14 and MCF-7-14 CL6 cells as well as MDA-MB-231 cells.</p> <p>Conclusions</p> <p>MCF-7-14 cells are a novel model for breast cancer metastasis without requiring constitutive EMT and are categorized as a "metastable phenotype", which can be distinguished from both epithelial and mesenchymal cells. The alterations and characteristics of MCF-7-14 cells, especially nuclear β-catenin and CD44 upregulation, may characterize invasive cell populations in breast cancer.</p

    産後うつとボンディングの関連の経産による変化: 子どもの健康と環境に関する全国調査からの経時的な結果より

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    富山大学・富医薬博乙77号・土田 暁子・2020/11/25関連論文Tsuchida A, Hamazaki K, Matsumura K, Miura K, Kasamatsu H, Inadera H; Japan Environment and Children\u27s Study (JECS) Group. Changes in the association between postpartum depression and mother-infant bonding by parity: Longitudinal results from the Japan Environment and Children\u27s Study. J Psychiatr Res. 2019 Mar;110:110-116. doi: 10.1016/j.jpsychires.2018.11.022. Epub 2018 Nov 28. PMID: 30616158.富山大
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