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In this study, the new synthesized magnetic nanoparticles based on amorphous carbon have been used as a sorbent in magnetic dispersive solid-phase extraction prior to dispersive liquid-liquid micro-extraction. The developed method was applied for analysis of ten pesticides from different fruit juice samples by gas chromatography-flame ionization detection. In this work, a few mg of the sorbent is added into an aqueous solution containing the analytes. Adsorption and desorption of the compounds of interest are accelerated by vortexing and sonication, respectively. To achieve high enrichment factors, a suitable organic solvent (iso-propanol) is used to elute the target analytes from the nanosorbent. The obtained iso-propanol is phased and 1,1,2-trichloroethane are employed as the disperser and extraction solvents, respectively, in the following micro-extraction procedure. The synthesized magnetic nanoparticles were characterized by scanning electron microscope, X-ray diffraction, vibrating sample magnetometer, and Fourier-transform infrared spectrophotometer. To achieve the high extraction efficiency and optimum conditions, all parameters that could affect the extraction yield were investigated. Under optimum conditions, the method had broad linear ranges with a proper linearity (r2 ≥ 0.9987). Limits of detection and quantification for analysis of the selected pesticides were found in the ranges of 0.5-1.0 and 1.7-3.3 µg L-1, respectively. High enrichment factors and extraction recoveries were obtained in the ranges of 321-438 and 64-88%, respectively. To evaluate repeatability of the method, it was performed on two sets of standard solutions at the concentrations of 10 and 50 µg L-1 (each analyte). Relative standard deviations varied in the ranges of 2-6% and 4-7% for intra- (n = 6) and inter-day (n = 5) precisions, respectively.

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Natural killer (NK) cells are unique innate immune cells that mediate anti-viral and anti-tumor responses. Thus, they might hold great potential for cancer immunotherapy. NK cell adoptive immunotherapy in humans has shown modest efficacy. In particular, it has failed to demonstrate therapeutic efficiency in the treatment of solid tumors, possibly due in part to the immunosuppressive tumor microenvironment (TME), which reduces NK cell immunotherapy's efficiencies. It is known that immune checkpoints play a prominent role in creating an immunosuppressive TME, leading to NK cell exhaustion and tumor immune escape. Therefore, NK cells must be reversed from their dysfunctional status and increased in their effector roles in order to improve the efficiency of cancer immunotherapy. Blockade of immune checkpoints can not only rescue NK cells from exhaustion but also augment their robust anti-tumor activity. In this review, we discussed immune checkpoint blockade strategies with a focus on chimeric antigen receptor (CAR)-NK cells to redirect NK cells to cancer cells in the treatment of solid tumors.

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BACKGROUND: A combination of magnetic solid-phase extraction using an efficient and cheap magnetic sorbent obtained from sand and dispersive liquid-liquid microextraction has been developed for the extraction of nine multiclass pesticides (clodinafop-propargyl, haloxyfop-R-methyl, fenoxaprop-P-ethyl, oxadiazon, penconazole, diniconazole, chlorpyrifos, fenazaquin, and fenpropathrin) from commercial fruit juices (sour cherry, pomegranate, grape, watermelon, orange, apricot, and peach juices). The enriched pesticides were determined by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The sorbent was natural iron oxide entrapped in silica along with some impurities. In this method, to extract the analytes from the samples, an appropriate amount of the magnetic sorbent (at mg level) is added. Then the sorbent particles are isolated from the solution using an external magnetic field and the adsorbed analytes are desorbed from the sorbent by acetone. In the following, a dispersive liquid-liquid microextraction procedure is carried out to concentrate the analytes more and to reach low limits of detection. RESULTS: Under optimized extraction conditions, the method revealed satisfactory repeatability (relative standard deviation ≤8% for intra-day and inter-day precision), reasonable extraction recovery (43.3-55.9%), high enrichment factors (433-559), and low limits of detection (0.45-0.89 µg L-1 ). CONCLUSION: The method was applied in the analysis of pesticides in various fruit juices. Chlorpyrifos was found in peach juice at a concentration of 27 ± 2 µg L-1 (n = 3) using a gas chromatography-flame ionization detector. To verify the results, the peach juice was also injected into gas chromatography-mass spectrometry after applying the proposed extraction method. © 2022 Society of Chemical Industry.

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INTRODUCTION: Breast cancer (BC) is the first common neoplastic malignancy and the second leading cause of death in women worldwide. Conventional treatments for BC are often associated with severe side effects and may even lead to late recurrence. For this reason, in recent years, cancer immunotherapy (e.g. cancer vaccines), a novel approach based on the specificity and amplification of acquired immune responses, has been considered as a potential candidate in particular to treat metastatic BC. AREAS COVERED: In this review, we summarize and discuss the recent development of therapeutic vaccines for BC, use of specific BC cellular antigens, antigen selection, and probable causes for their insufficient effectiveness. EXPERT OPINION: Despite development of several different BC vaccines strategies including protein/peptide, dendritic cell, and genetic vaccines, until now, no BC vaccine has been approved for clinical use. Most of the current BC vaccines themselves fail to bring clinical benefit to BC patients and are applied in combination with radiotherapy, chemotherapy, or targeted therapy. It is hoped that with advances in our knowledge about tumor microenvironment and the development of novel combination strategies, the tumor immunosuppressive mechanisms can be overcome and prolonged immunologic and effective antitumor response can be developed in patients.

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BACKGROUND: A new solvent, deep eutectic solvent, in which there is growing interest, has been prepared and used as an extraction solvent in the dispersive liquid-liquid method of microextraction. To prepare the solvent, dichloroacetic acid, l-menthol, and n-butanol are mixed at a molar ratio of 4:1:1 and the deep eutectic solvent is formed after heating. Then a dispersive liquid-liquid microextraction method using the prepared solvent is used for the extraction and preconcentration of some pesticides from an aqueous sample. To carry out the procedure, the deep eutectic solvent is mixed with methanol and rapidly injected by a syringe into the aqueous sample containing the analytes. After centrifuging, an aliquot of the sedimented phase is injected into the gas chromatograph. The influence of several variables on the extraction efficiency was investigated and optimized. RESULTS: Extraction recoveries and enrichment factors were obtained in the ranges of 53-86% and 1760-2853, respectively. The intra- (n = 6) and inter-day (n = 5) precision of the method was satisfactory, with relative standard deviations ≤ 7% obtained at two concentrations of 10 and 50 µg L-1 of each analyte. Moreover, detection and quantification limits for the target analytes were obtained in the ranges of 0.11-0.23 and 0.38-0.74 µg L-1 , respectively. CONCLUSION: Different samples, including green tea, rose water, lemon balm, mint, and pussy willow distillates were analyzed successfully using the method that was developed, and chlorpyrifos was found in rose water at a concentration of 17 ± 1 µg L-1 (n = 3). © 2019 Society of Chemical Industry.

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A green dispersive liquid-liquid microextraction using a new high density deep eutectic solvent (as an extraction solvent) has been developed and utilized in the simultaneous preconcentration and extraction of seven pesticides in honey followed by gas chromatography-flame ionization detection. The deep eutectic solvent is synthesized using menthol (as a hydrogen bond acceptor) and dichloroacetic acid (as a hydrogen bond donor) at a molar ratio of 1:2. Initially the analytes are extracted into acetone from the sample. After centrifuging, the synthesized deep eutectic solvent is added to the extract obtained from the previous step. Then this mixture is quickly injected into deionized water by a syringe for more concentration. A cloudy solution is formed by dispersion of fine droplets of the deep eutectic solvent by acetone into the aqueous solution and the pesticides are transferred into the extraction solvent. After extraction, phase separation is performed by centrifugation and the enriched analytes in the sedimented phase are determined. The influence of different parameters affecting the extraction efficiency was investigated and optimized. Under the optimized extraction conditions, enrichment factor for the analytes was obtained in the range of 279-428 with extraction recovery of 56-86%. Limits of detection and quantification were obtained in the ranges of 0.32-1.2 and 1.1-4.0 ng g-1, respectively. Relative standard deviations were ≤ 7% for intra- (n = 6) and inter-day (n = 5) precisions calculated at two concentrations of 10 and 50 ng g-1 of each analyte. Finally, some honey samples were effectively analyzed by the proposed method and diazinon was determined at ng g-1 concentration in one sample.

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Purpose: In this investigation, a new version of magnetic solid phase extraction (MSPE) performed in a narrow-bore tube has been proposed. In this study, hydrophobic octyl (C8) functionalized Fe3O4 magnetic nanoparticles (MNPs) stabilized by SiOH groups (Fe3O4@SiO2@C8) are used as magnetic nano-sorbents for the extraction of cardiovascular drugs from human plasma prior to their determination by high performance liquid chromatography-photodiode array detection. Methods: After precipitation of the plasma proteins, the supernatant is diluted with deionized water and filled into the narrow-bore tube. Then mg-level of the sorbent is added into the tube. The sorbent is dispersed and moved down through the solution instead of passing the solution from the cartridge. Using an external magnet, the collected nano-sorbents at the bottom of the tube are transferred on top of the solution and released to move down through the solution for three times to increase the extraction efficiency. Results: The linearity of the assay was ranging from 0.4-500 mg mL-1. The limits of detection and quantification of the method were obtained in the ranges of 0.05-0.07 and 0.16-0.24 mg L-1, respectively. The extraction recoveries were obtained in the range of 31-49%. Intra- and inter-day precisions were calculated and obtained in the ranges of 5-8 and 7%-9% for 0.5 mg L-1 of each analyte, and 5-6 and 6%-8% for 2 mg L-1 of each analyte, respectively. Conclusion: The proposed method was successfully used in determination of the studied drugs in patient's plasmas.

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BACKGROUND: A method has been developed based on a three-phase system, followed by dispersive liquid-liquid microextraction for the extraction of seven pesticides from soya milk prior to analysis by gas chromatography-flame ionization detection. The base of this method is the different extraction capability of the components of soya milk according to each of the phases involved. In this procedure, a homogeneous solution consisting of soya milk and a water-miscible solvent (acetonitrile) is separated into two phases in the presence of Na2 SO4 and the analytes are extracted into the produced acetonitrile droplets. The acetonitrile phase is mixed with a pre-concentration solvent to perform the next microextraction procedure for further enrichment of the analytes. RESULTS: Limits of detection and quantification were reached in the ranges of 0.11-0.35 and 0.35-1.20 µg L-1 , respectively. Enrichment factors and extraction recoveries were in the ranges of 562-933 and 56-93%, respectively. Relative standard deviations were ≤7% for intra- (n = 6) and inter-day (n = 5) precisions at two concentrations of 10 and 50 µg L-1 of each analyte. CONCLUSION: The proposed method was applied to the analysis of pesticides in soya milk samples at µg L-1 concentrations. © 2019 Society of Chemical Industry.

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In the present study, a new extraction method based on a three-phase system, liquid-liquid-liquid extraction, followed by dispersive liquid-liquid microextraction has been developed and validated for the extraction and preconcentration of three commonly prescribed tricyclic antidepressant drugs - amitriptyline, imipramine, and clomipramine - in human plasma prior to their analysis by gas chromatography-flame ionization detection. The three phases were an aqueous phase (plasma), acetonitrile and n-hexane. The extraction mechanism was based on the different affinities of components of the biological sample (lipids, fatty acids, pharmaceuticals, inorganic ions, etc.) toward each of the phases. This provided high selectivity toward the analytes since most interferences were transferred into n-hexane. In this procedure, a homogeneous solution of the aqueous phase (plasma) and acetonitrile (water-soluble extraction solvent) was broken by adding sodium sulfate (as a phase separating agent) and the analytes were extracted into the fine droplets of the formed acetonitrile. Next, acetonitrile phase was mixed with 1,2-dibromoethane (as a preconcentration solvent at microliter level) and then the microextraction procedure mentioned above was performed for further enrichment of the analytes. Under the optimum extraction conditions, limits of detection and lower limits of quantification for the analytes were obtained in the ranges of 0.001-0.003 and 0.003-0.010 µg mL-1 , respectively. The obtained extraction recoveries were in the range of 79-98%. Intra- and inter-day precisions were < 7.5%. The validated method was successfully applied for determination of the selected drugs in human plasma samples obtained from the patients who received them.

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A new sample preparation method based on liquid-liquid-liquid extraction combined with dispersive liquid-liquid microextraction followed by gas chromatography-flame ionization detection has been reported for the extraction/preconcentration and determination of trace levels of twelve pesticide residues from different samples with high content of solids without filtration. This method consists of a three-phase system including an aqueous phase (sample solution), acetonitrile, and hexane. The extraction mechanism is based on different affinities of the substances from the sample matrices towards each of the involved phase, which provides a high selectivity to the process. In other words, interfering hydrophobic compounds are transferred into hexane and will not be present in the final extract. Furthermore, ionic and polar compounds are retained in the aqueous phase. Therefore, only semi-polar compounds such as the studied pesticides are extracted into acetonitrile. In this method, a homogeneous solution of the aqueous phase and acetonitrile (a water-soluble extraction solvent) forms two clearly separated phases in the presence of sodium sulfate (as a phase separation agent) and simultaneously the analytes are extracted into the fine droplets of the acetonitrile collected on the surface of the aqueous phase. To achieve high enrichment factors, the acetonitrile phase is mixed with 1,2-dibromoethane (as a preconcentration solvent) at µL-level to perform the following dispersive liquid-liquid microextraction procedure. Several parameters that can affect extraction efficiency including kind and volume of extraction solvent, type and concentration of phase separation agent, hexane volume, kind of preconcentration solvent, and ionic strength were studied and optimized. Under the optimal conditions, extraction recoveries were obtained in the range of 53-93% and the calibration curves were linear in wide ranges with correlation coefficients ≥ 0.9983. Intra- (n = 6) and inter-day (n=5) precisions of the method were satisfactory with relative standard deviations less than or equal to 7% (at two concentrations of 10 and 50µgL-1 of each analyte). Moreover, the detection limits and enrichment factors of the target analytes were obtained in the ranges of 0.43-1.2µgL-1 and 264-464, respectively. Finally, the proposed method was applied on different fruit and vegetable samples and diazinon was determined in apple sample at a concentration of 0.030µgg-1.

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Venous thromboembolism (VTE) is a complication commonly encountered in cancer patients and is considered to be a major cause of morbidity and mortality. The genetic polymorphisms of thrombophilic factors in cancer patients have been focused on during the last few years. However, the number of available studies on the association between prostate cancer and thromboembolic diseases is limited. Prostate cancer is one of the four major types of cancer and its development is affected by a variety of environmental and genetic factors. In the present study we aimed to focus on the effects of thromboembolic factor gene variations on the risk of prostate cancer. In order to conduct our prospective study, we used amplification-refractory mutation system-polymerase chain reaction to investigate three polymorphisms [factor V Leiden (FVL) G1691A, factor II (prothrombin, PTH) G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T] in prostate cancer patients, via comparison with normal individuals. The results demonstrated no significant differences in FVL and PTH gene variations between cases and controls (P>0.05). Although some cases with the T allele of MTHFR 677 were identified, no significant solidarity was established by statistical analysis (P>0.05). Therefore, non-genetic factors that may disturb homeostatic balance should also be considered in future studies, in order to determine the exact association between VTE and prostate cancer.