62 research outputs found

    Optimization of Ionic Liquid Based Simultaneous Ultrasonic- and Microwave-Assisted Extraction of Rutin and Quercetin from Leaves of Velvetleaf ( Abutilon theophrasti

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    An ionic liquids based simultaneous ultrasonic and microwave assisted extraction (ILs-UMAE) method has been proposed for the extraction of rutin (RU), quercetin (QU), from velvetleaf leaves. The influential parameters of the ILs-UMAE were optimized by the single factor and the central composite design (CCD) experiments. A 2.00 M 1-butyl-3-methylimidazolium bromide ([C4mim]Br) was used as the experimental ionic liquid, extraction temperature 60°C, extraction time 12 min, liquid-solid ratio 32 mL/g, microwave power of 534 W, and a fixed ultrasonic power of 50 W. Compared to conventional heating reflux extraction (HRE), the RU and QU extraction yields obtained by ILs-UMAE were, respectively, 5.49 mg/g and 0.27 mg/g, which increased, respectively, 2.01-fold and 2.34-fold with the recoveries that were in the range of 97.62–102.36% for RU and 97.33–102.21% for QU with RSDs lower than 3.2% under the optimized UMAE conditions. In addition, the shorter extraction time was used in ILs-UMAE, compared with HRE. Therefore, ILs-UMAE was a rapid and an efficient method for the extraction of RU and QU from the leaves of velvetleaf

    Flow-mediated dilatation to relieve puncture-induced radial artery spasm: A pilot study

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      Background: Puncture-induced radial artery spasm (RAS) may extend the duration of coronary an­giography (CAG) or cause transradial access failure. Flow-mediated dilatation (FMD), a widely-used noninvasive approach for assessing endothelial function, was reported to remove the entrapped radial sheath after percutaneous coronary intervention. Herein, the efficacy and safety of FMD in treating puncture-induced RAS before transradial CAG was investigated. Methods: Ninety patients with puncture-induced RAS were randomized in a 1:1:1 ratio into three groups: FMD group was immediately treated with blockage of brachial artery blood for 5 min using a sphygmomanometric cuff and then rapid relief; nitroglycerin (NTG) group was administered with 0.5 mg sublingual NTG instantly; and the no-therapy group was treated with a wait-and-watch strategy. The time of radial pulse recovery, and regional and systemic complications were recorded. Results: The rate of radial pulse recovery within 30 min in FMD group was significantly higher than that in no-therapy group (97% vs. 73%, p = 0.026). The median time to return of radial pulse in FMD group and NTG group was significantly shorter than that in no-therapy group (7 [6.5–9] min vs. 15 [12–18] min, 8 [7–9] min vs. 15 [12–18] min, respectively; both p < 0.001). Headache and decreased blood pressure were more prevalent in NTG group than those in FMD and no-therapy groups. Conclusions: FMD is a feasible, noninvasive and nonpharmacological approach to relieve RAS and facilitate radial artery cannulation after an initial failed attempt. (Cardiol J 2018; 25, 1: 1–6

    Compared the efficacy of mitoxantrone hydrochloride injection for tracing with radionuclide in sentinel lymph node biopsy of breast cancer

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    Background and purpose: Both domestic and foreign guidelines recommend the use of radionuclide as sentinel lymph node (SLN) biopsy (SLNB) tracer, however this technique has not been popularized in China for a variety of reasons. Mitoxantrone hydrochloride injection for tracing (MHI), a new strategy to identify lymph nodes, has not been tested for axillary node staging in breast cancer. This multicenter, self-controlled, non-inferiority trial aimed to evaluate the differences between MHI and radionuclide in SLNB tracing. Methods: The trial was conducted across 7 hospitals from December 2019 to December 2020. Patients with early-stage breast cancer received MHI and radionuclide (technetium 99 labeled sulfur colloid, 99mTc-Sc) as SLN tracers during the surgery. The number of SLNs detected and sentinel node detection rates of MHI and radionuclide were counted to evaluate differences in the tracing effects between the two tracers. Results: SLN detection rates of MHI and radionuclide were 96.9% (370/382) and 97.4% (372/382), respectively, with no significant difference (P>0.05). SLNs were co-detected by both tracers in 362 (94.7%) patients; 16 (4.1%) had adverse events possibly related to the trial drugs. Conclusion: In this study, it was found that the lymphatic tracing ability of MHI was not inferior to that of radionuclide. Meanwhile, the use of MHI does not require special instrument/equipment assistance

    Application of Ionic Liquids in the Microwave-Assisted Extraction of Proanthocyanidins from Larix gmelini Bark

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    Ionic liquid based, microwave-assisted extraction (ILMAE) was successfully applied to the extraction of proanthocyanidins from Larix gmelini bark. In this work, in order to evaluate the performance of ionic liquids in the microwave-assisted extraction process, a series of 1-alkyl-3-methylimidazolium ionic liquids with different cations and anions were evaluated for extraction yield, and 1-butyl-3-methylimidazolium bromide was selected as the optimal solvent. In addition, the ILMAE procedure for the proanthocyanidins was optimized and compared with other conventional extraction techniques. Under the optimized conditions, satisfactory extraction yield of the proanthocyanidins was obtained. Relative to other methods, the proposed approach provided higher extraction yield and lower energy consumption. The Larix gmelini bark samples before and after extraction were analyzed by Thermal gravimetric analysis, Fourier-transform infrared spectroscopy and characterized by scanning electron microscopy. The results showed that the ILMAE method is a simple and efficient technique for sample preparation

    Temporal and Spatial Profiling of Root Growth Revealed Novel Response of Maize Roots under Various Nitrogen Supplies in the Field

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    A challenge for Chinese agriculture is to limit the overapplication of nitrogen (N) without reducing grain yield. Roots take up N and participate in N assimilation, facilitating dry matter accumulation in grains. However, little is known about how the root system in soil profile responds to various N supplies. In the present study, N uptake, temporal and spatial distributions of maize roots, and soil mineral N (Nmin) were thoroughly studied under field conditions in three consecutive years. The results showed that in spite of transient stimulation of growth of early initiated nodal roots, N deficiency completely suppressed growth of the later-initiated nodal roots and accelerated root death, causing an early decrease in the total root length at the rapid vegetative growth stage of maize plants. Early N excess, deficiency, or delayed N topdressing reduced plant N content, resulting in a significant decrease in dry matter accumulation and grain yield. Notably, N overapplication led to N leaching that stimulated root growth in the 40–50 cm soil layer. It was concluded that the temporal and spatial growth patterns of maize roots were controlled by shoot growth and local soil Nmin, respectively. Improving N management involves not only controlling the total amount of chemical N fertilizer applied, but also synchronizing crop N demand and soil N supply by split N applications

    A Microwave-Assisted Simultaneous Distillation and Extraction Method for the Separation of Polysaccharides and Essential Oil from the Leaves of Taxus chinensis Var. mairei

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    An efficient microwave-assisted simultaneous distillation and extraction (MA-SDE) method has been developed for the separation of polysaccharides and essential oil from Taxus chinensis var. mairei. The key operating parameters for MA-SDE were optimized by single factor and central composite design experiments, and the optimal conditions were found to include a particle size of 60–80 mesh, liquid/solid ratio of 22.5 mL/g, extraction time of 17.5 min, microwave power of 547 W, and dichloromethane was used as the extraction solvent of the essential oil. The yields obtained for polysaccharides and essential oil under the optimized conditions were 6.39% ± 0.12% and 0.27% ± 0.03%, respectively. The MA-SDE method was also compared with conventional heat reflux extraction (HRE) and hydrodistillation extraction (HDE). The MA-SDE method not only allowed for the simultaneous extraction of polysaccharides and essential oil, but also completed the task with a much shorter extraction time of 17.5 min (HRE and HDE required 3 and 6 h, respectively). Furthermore, the MA-SDE method gave increased extraction yields for polysaccharides (1.14-fold higher than HRE) and essential oil (1.23-fold higher than HDE). Based on these results, this MA-SDE method represents a rapid and efficient technique for the simultaneous extraction of polysaccharides and essential oil

    Development of an Ionic Liquid-Based Ultrasonic/Microwave-Assisted Simultaneous Distillation and Extraction Method for Separation of Camptothecin, 10-Hydroxycamptothecin, Vincoside-Lactam, and Essential Oils from the Fruits of Camptotheca acuminata Decne

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    An ionic liquid-based ultrasonic/microwave-assisted simultaneous distillation and extraction (IL-UMASDE) method for isolating camptothecin (CPT), 10-hydroxycamptothecin (HCPT), vincoside-lactam (VCS-LT), and essential oils (EOs) from Camptotheca acuminata Decne fruits was developed. The important parameters were optimized using single-factor and central composite design experiments. The optimum conditions were 0.75 M 1-octyl-3-methylimidazolium ([C8mim]Br) as the extraction solvent, a liquid–solid ratio of 13.7 mL/g, an extraction time of 33.2 min, a microwave power of 582 W, and a fixed ultrasonic power of 50 W. The yields of CPT, HCPT, and VCS-LT obtained under the optimum conditions were 2.463, 0.164, and 0.297 mg/g, respectively; these are 1.08-, 1.12-, and 1.04-fold higher, respectively, than those obtained by conventional 55% ethanol heat reflux extraction (HRE). The extraction time for the equilibrium yields of CPT, HCPT and VCS-LT using IL-UMASDE was 33.6%, 58.5%, 63.1%, and 66.8%, respectively, less than the corresponding times using IL-MASDE, IL-ultrasonic-assisted extraction (IL-UAE), 55% ethanol UAE and 55% ethanol HRE. The yield of EOs obtained using IL-UMASDE was 0.793 mg/g, i.e., 1.31-fold higher than that obtained by conventional hydrodistillation extraction (HDE). The components of the EOs obtained using IL-UMASDE and HDE were similar. The extraction time for the equilibrium yields of EOs using IL-UMASDE is 33.6%, 58.5%, 52.6%, and 72.3% lower than those for IL-MASDE, water-UMASDE, water-MASDE, and HDE, respectively. Compared with other extraction methods, IL-UMASDE gave the highest yields of CPT, HCPT, VCS-LT, and EOs and also had the shortest extraction time. IL-UMASDE is a potential green and highly efficient technique for the extraction of CPT, HCPT, VCS-LT, and EOs from Camptotheca acuminata Decne fruits

    The Galloyl Catechins Contributing to Main Antioxidant Capacity of Tea Made from Camellia sinensis in China

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    Total polyphenol content, catechins content, and antioxidant capacities of green, dark, oolong, and black teas made from Camellia sinensis in China were evaluated. The total polyphenol content of 20 samples of tea was in the range of 7.82–32.36%. Total catechins content was in the range of 4.34–24.27%. The antioxidant capacity of tea extract was determined by the oxygen radical absorbance capacity (ORAC) test and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging test. Total polyphenol content, catechins content, and antioxidant capacity decreased in the following order: green > oolong > black > dark tea. A positive correlation existed between the antioxidant capacity and total polyphenol content or catechins content (R2=0.67–0.87). The antioxidant capacities of five major catechins (epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epicatechin, epigallocatechin, and catechin) were determined by online HPLC DPPH radical-scavenging; the antioxidant activity of tea was mainly attributed to the esterified catechins (EGCG or ECG)
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