64 research outputs found

    Effectiveness of a new gelatin sealant system for dural closure.

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    Objectives:Watertight dural closure is imperative after neurosurgical procedures because inadequately treated leakage of cerebrospinal fluid (CSF) can have serious consequences. In this study, the authors test the use of a new gelatin glue as a dural sealant in in vitro and in vivo canine models of transdural CSF leakage.Methods:The in vitro model was sutured semicircles of canine dura mater and artificial dural substitute. The sutures were sealed with gelatin glue (n  =  20), fibrin glue (n  =  20), or a polyethylene glycol (PEG)-based hydrogel sealant (n  =  20). Each sample was set in a device to measure water pressure, and pressure was increased until leakage occurred. Bonding strength was subjectively evaluated. The in vivo model was dogs who underwent dural excision and received either no sealant (control group; n  =  5) or gelatin glue sealant (n  =  5) before dural closure. Twenty-eight days post-surgery, the maximum intracranial pressure was measured at the cisterna magna using Valsalva maneuver and tissue adhesion was evaluated.Results:The water pressure at which leakage occurred in the in vitro model was higher with gelatin glue (76·5 ± 39·8 mmHg) than with fibrin glue (38·3 ± 27·4 mmHg, P < 0·001) or the PEG-based hydrogel sealant (46·3 ± 20·9 mmHg, P  =  0·007). Bonding strength was higher for the gelatin glue than fibrin glue (P < 0·001) or PEG-based hydrogel sealant (P  =  0·001). The maximum intracranial pressure in the in vivo model was higher for the gelatin glue group (59·0 ± 2·2 mmHg) than the control group (13·8 ± 4·0 mmHg, P < 0·001). Tissue adhesion was lower for the gelatin glue group than the control group (P  =  0·005).Discussion:The new gelatin glue provides an effective watertight closure when used as an adjunct to sutured dural repair.博士(医学)・甲第634号・平成27年5月28日© 2015 W. S. Maney & Son LtdThe definitive version is available at " http://dx.doi.org/10.1179/1743132814Y.0000000342

    非小細胞肺がんと非小細胞肺がんから発生した転移性脳腫瘍における光線力学的測定によりPEPT1の発現は5-ALAから代謝されるプロトポルフィリンⅨの蓄積において正の相関をする

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    BACKGROUND: Recently, 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX fluorescence was reported to be a useful tool during total surgical resection of high-grade gliomas. However, the labeling efficacy of protoporphyrin IX fluorescence is lower in metastatic brain tumors compared to that in high-grade gliomas, and the mechanism underlying protoporphyrin IX fluorescence in metastatic brain tumors remains unclear. Lung cancer, particularly non-small cell lung cancer (NSCLC), is the most common origin for metastatic brain tumor. Therefore, we investigated the mechanism of protoporphyrin IX fluorescence in NSCLC and associated metastatic brain tumors. METHODS: Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) was employed to evaluate the protein and mRNA levels of five transporters and enzymes involved in the porphyrin biosynthesis pathway: peptide transporter 1 (PEPT1), hydroxymethylbilane synthase (HMBS), ferrochelatase (FECH), ATP-binding cassette 2 (ABCG2), and heme oxygenase 1 (HO-1). The correlation between protein, mRNA, and protoporphyrin IX levels in NSCLC cells were evaluated in vitro. Immunohistochemistry was used to determine proteins that played a key role in intraoperative protoporphyrin IX fluorescence in clinical samples from patients with NSCLC and pathologically confirmed metastatic brain tumors. RESULTS: A significant correlation between PEPT1 expression and protoporphyrin IX accumulation in vitro was identified by western blotting (P = 0.003) and qRT-PCR (P = 0.04). Immunohistochemistry results indicated that there was a significant difference in PEPT1 between the intraoperative protoporphyrin IX fluorescence-positive and protoporphyrin IX fluorescence-negative groups (P = 0.009). CONCLUSION: Expression of PEPT1 was found to be positively correlated with 5-ALA-induced protoporphyrin IX accumulation detected by photodynamic reaction in metastatic brain tumors originating from NSCLC.博士(医学)・甲第714号・令和元年年6月26日Copyright © 2019 Elsevier B.V. All rights reserved

    ヒト細胞傷害性γδT細胞は膠芽腫細胞株を殺傷する:膠芽腫患者に対する免疫細胞治療の意義

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    Glioblastoma (GBM) is a highly aggressive brain tumor for which novel therapeutic approaches, such as immunotherapy, are urgently needed. Zoledronate (ZOL), an inhibitor of osteoclastic activity, is known to stimulate peripheral blood-derived γδT cells and sensitize tumors to γδT cell-mediated killing. To investigate the feasibility of γδT cell-based immunotherapy for patients with GBM, we focused on the killing of GBM cell lines by γδT cells and the molecular mechanisms involved in these cell–cell interactions. Peripheral blood mononuclear cells were expanded in ZOL and interleukin (IL)-2 for 14 days, and γδT cells were enriched in the expanded cells by the immunomagnetic depletion of αβT cells. Gliomas are resistant to NK cells but susceptible to lymphokine-activated killer cells and some cytotoxic T lymphocytes. When the γδT cell-mediated killing of three GBM cell lines (U87MG, U138MG and A172 cells) and an NK-sensitive leukemia cell line (K562 cells) were tested, 32 % U87MG, 15 % U138MG, 1 % A172, and 50 % K562 cells were killed at an effector:target ratio of 5:1. The γδT cell-mediated killing of all three GBM cell lines was significantly enhanced by ZOL and this ZOL-enhanced killing was blocked by an anti-T cell receptor (TcR) antibody. These results indicated that TcR γδ is crucial for the recognition of ZOL-treated GBM cells by γδT cells. Since the low level killing of GBM cells by the γδT cells was enhanced by ZOL, γδT cell-targeting therapy in combination with ZOL treatment could be effective for patients with GBM.博士(医学)・甲第635号・平成27年5月28日© Springer Verlag. The definitive version is available at " http://dx.doi.org/10.1007/s11060-013-1258-4

    In vivo imaging models of bone and brain metastases and pleural carcinomatosis with a novel human EML4-ALK lung cancer cell line

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    がん進展制御研究所EML4-ALK lung cancer accounts for approximately 3-7% of non-small-cell lung cancer cases. To investigate the molecular mechanism underlying tumor progression and targeted drug sensitivity/resistance in EML4-ALK lung cancer, clinically relevant animal models are indispensable. In this study, we found that the lung adenocarcinoma cell line A925L expresses an EML4-ALK gene fusion (variant 5a, E2:A20) and is sensitive to the ALK inhibitors crizotinib and alectinib. We further established highly tumorigenic A925LPE3 cells, which also have the EML4-ALK gene fusion (variant 5a) and are sensitive to ALK inhibitors. By using A925LPE3 cells with luciferase gene transfection, we established in vivo imaging models for pleural carcinomatosis, bone metastasis, and brain metastasis, all of which are significant clinical concerns of advanced EML4-ALK lung cancer. Interestingly, crizotinib caused tumors to shrink in the pleural carcinomatosis model, but not in bone and brain metastasis models, whereas alectinib showed remarkable efficacy in all three models, indicative of the clinical efficacy of these ALK inhibitors. Our in vivo imaging models of multiple organ sites may provide useful resources to analyze further the pathogenesis of EML4-ALK lung cancer and its response and resistance to ALK inhibitors in various organ microenvironments. © 2015 The Authors

    CFD analysis of microchannel emulsification: Droplet generation process and size effect of asymmetric straight flow-through microchannels

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    This is the author’s version of a work that was accepted for publication in Chemical Engineering Science. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Chemical Engineering Science, Volume 66, Issue 22, DOI 10.1016/j.ces.2011.07.061Asymmetric straight flow-through microchannel (MC) arrays are high-performance MC emulsification devices for stable mass production of uniform droplets. This paper presents computational fluid dynamics (CFD) simulation and analysis of the generation of soybean oil-in-water emulsion droplets via asymmetric straight flow-through MCs, each consisting of a microslot and a narrow MC. We also used CFD to investigate the effects of the channel size and the flow of the dispersed phase on MC emulsification using asymmetric straight flow-through MCs with a characteristic channel size of 5 to 400 μm. The overall shape of an oil-water interface and the time scale during droplet generation via a control asymmetric straight flow-through MC were appropriately simulated. Better insight was obtained on the flow profile of the two phases and the internal pressure balance of the dispersed phase during droplet generation. Comparison of the CFD and experiment results also provided insight into dynamic interfacial tension during droplet generation. Successful droplet generation was observed below a critical dispersed-phase velocity. In this case, the resultant droplet size was proportional to the channel size and was not sensitive to the dispersed-phase velocity applied. The maximum droplet generation rate per channel was inversely proportional to the channel size, unless the buoyancy force did not promote droplet detachment. The maximum droplet productivity per unit area of an asymmetric straight flow-through MC array was estimated to be constant, regardless of channel size

    Hybrid Processing

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    Human societies have converted biomass into energy and products for millennia using both biochemical and thermochemical processes. Familiar examples of biochemical processing includes fermentation of sugar- or starch-rich crops and milk into sauerkraut, beer, wine, yogurt, and cheese. Familiar examples of thermochemical processing include baking and cooking of food and burning wood for heat and power
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