Browsing by Subject "Methylene Blue"

Now showing 1 - 3 of 3
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    Functional elastic hydrogel as recyclable membrane for the adsorption and degradation of methylene blue.
    (PloS one, 2014-01) Bao, Song; Wu, Dongbei; Wang, Qigang; Su, Teng
    Developing the application of high-strength hydrogels has gained much attention in the fields of medical, pharmacy, and pollutant removal due to their versatility and stimulus-responsive properties. In this presentation, a high-strength freestanding elastic hydrogel membrane was constructed by clay nanosheets, N, N-dimethylacrylamide and 2-acrylamide-2-methylpropanesulfonic acid for adsorption of methylene blue and heavy metal ions. The maximum values of elongation and Young's modulus for 0.5% AMPSNa hydrogel were 1901% and 949.4 kPa, respectively, much higher than those of traditional hydrogels. The adsorptions were confirmed to follow pseudo-second kinetic equation and Langmuir isotherm model fits the data well. The maximum adsorption capacity of hydrogel towards methylene blue was 434.8 mg g(-1). The hydrogel also exhibited higher separation selectivity to Pb(2+) than Cu(2+). The methylene blue adsorbed onto the hydrogel membrane can be photocatalytically degraded by Fenton agent and the hydrogel membrane could be recycled at least five times without obvious loss in mechanical properties. In conclusion, this presentation demonstrates a convenient strategy to prepare tough and elastic clay nanocomposite hydrogel, which can not only be applied as recyclable membrane for the photocatalytic degradation of organic dye, but also for the recovery of valuables.
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    Hydroxocobalamin or Methylene Blue for Vasoplegic Syndrome in Adult Cardiothoracic Surgery.
    (Journal of cardiothoracic and vascular anesthesia, 2022-02) Kram, Shawn J; Kram, Bridgette L; Cook, Jennifer C; Ohman, Kelsey L; Ghadimi, Kamrouz

    Objective

    To compare hydroxocobalamin and methylene blue for the treatment of vasopressor-refractory vasoplegic syndrome (VS) after adult cardiac surgery with cardiopulmonary bypass (CPB).

    Design

    A retrospective, propensity-matched, cohort study was performed. The primary endpoints were the percentage change in vasopressor use at 30, 60, and 120 minutes, characterized as both norepinephrine equivalents and vasoactive inotropic score. Eligible patients who received methylene blue were matched 3:1 with patients who received hydroxocobalamin based on sequential organ failure assessment score, preoperative mechanical circulatory support, CPB duration, and use of pre-CPB vasopressors, angiotensin-converting enzyme inhibitors, or beta-blockers.

    Setting

    A quaternary care academic medical center.

    Participants

    Adult patients who underwent cardiac surgery with CPB from July 2013 to June 2019.

    Interventions

    Patients were included who received either hydroxocobalamin (5,000 mg) or methylene blue (median 1.2 mg/kg) for VS in the operating room during the index surgery or in the intensive care unit up to 24 hours after CPB separation.

    Measurements and main results

    Of the 142 included patients, 120 received methylene blue and 22 received hydroxocobalamin. After matching, 66 patients in the methylene blue group were included in the analysis. Baseline demographics, surgical characteristics, and vasoactive medications were similar between groups. There were no significant between-group differences in percentage change in norepinephrine equivalents or vasoactive inotropic score at each timepoint.

    Conclusions

    In adult patients undergoing cardiothoracic surgery using CPB with VS, the ability to reduce vasopressor use was similar with hydroxocobalamin compared with methylene blue.
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    Time-Resolved Synchronous Fluorescence for Biomedical Diagnosis.
    (Sensors (Basel), 2015-08-31) Zhang, Xiaofeng; Fales, Andrew; Vo-Dinh, Tuan
    This article presents our most recent advances in synchronous fluorescence (SF) methodology for biomedical diagnostics. The SF method is characterized by simultaneously scanning both the excitation and emission wavelengths while keeping a constant wavelength interval between them. Compared to conventional fluorescence spectroscopy, the SF method simplifies the emission spectrum while enabling greater selectivity, and has been successfully used to detect subtle differences in the fluorescence emission signatures of biochemical species in cells and tissues. The SF method can be used in imaging to analyze dysplastic cells in vitro and tissue in vivo. Based on the SF method, here we demonstrate the feasibility of a time-resolved synchronous fluorescence (TRSF) method, which incorporates the intrinsic fluorescent decay characteristics of the fluorophores. Our prototype TRSF system has clearly shown its advantage in spectro-temporal separation of the fluorophores that were otherwise difficult to spectrally separate in SF spectroscopy. We envision that our previously-tested SF imaging and the newly-developed TRSF methods will combine their proven diagnostic potentials in cancer diagnosis to further improve the efficacy of SF-based biomedical diagnostics.