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Amino acids are important building blocks of proteins in the human body, which are involved in many metabolic pathways. Patients with metabolic diseases such as phenylketonuria, tyrosinemia, and hepatic encephalopathy are genetically defective and cannot metabolize aromatic amino acids (AAA) in food; hence, a regular diet may lead to permanent physiological damage. For this reason, it is necessary to restrict the intake of AAA in their daily diet by limiting natural protein intake, while ensuring normal intake of low protein foods and supplementation with low-AAA protein equivalents. Sources of low-AAA protein equivalents currently rely on free amino acid complex mixtures and low-AAA peptides (also known as high-Fischer-ratio peptides), which have better absorption availability and palatability. AAA separation and analysis techniques are essential for the preparation and detection of low-AAA peptides. Researchers in this field have explored a variety of efficient adsorption materials to selectively remove AAA from complex protein hydrolysates and thus prepare low-AAA peptide foods, or to establish analysis strategies for AAA. Covering more than 70 publications on AAA removal and separation in the last decade from Web of Science Core Collection and China National Knowledge Infrastructure, this review analyzes the structural characteristics and physicochemical properties of AAA, and summarizes the technological progress of AAA removal based on adsorbents such as activated carbon and resin. The applications of two-dimensional nanomaterials, molecular imprinting, cyclodextrins, and metal-organic frameworks in AAA adsorption and analysis from three dimensions, i. e., sample pretreatment, chiral separation and adsorption sensing, are also reviewed. The mainstream adsorbents for AAA removal, such as activated carbon, still suffer from poor specificity and cause environmental pollution during post-use treatment. Existing AAA separating materials show impressive selective adsorption capability in food samples and chiral mixtures as well as high sensitivity in adsorption sensing. The development of an efficient detection technology for AAA may help in detecting trace AAA in food and in evaluating chiral AAA adulteration in food samples. By exploring the advantages and disadvantages of each type of technology, we provide support for the advancement of the removal and analysis techniques for AAA.

Hormone residues in food and drinking water endanger human health, therefore, on-site analysis techniques of superior performance are important for monitoring this risk. In this study, an ultra-sensitive photothermal lateral flow immunoassay (LFIA) for quantification of 17β-estradiol (E

The residues of bisphenol A (BPA) in milk packaging may transfer to milk, adversely affecting the human endocrine system. Consequently, to analyse or monitor BPA, it is imperative to develop rapid and effective approaches to BPA extraction from milk and milk packing as BPA is usually present in trace levels. Herein, we developed a rapid, simple, and low-cost dispersive-membrane-solid-phase-extraction (DME) for BPA with MIL-101(Cr) mixed-matrix-membrane (MMM). The MMM had large surface area (1322.09 m

This research proposes a Model Predictive Control (MPC) based path tracker controller. It is designed for maneuvering an autonomous driving vehicle to follow its desired trajectory smoothly and accurately. The proposed path tracker has the following features: i) formulated in the time and space mixed-domain to improved control accuracy ii) with consideration of vehicle dynamics; iii) with consideration of vehicle control delay. Simulation and field test results demonstrate that the maximum longitudinal speed error is 2.3km/h and the maximum lateral position error is 11cm. It is 27% smaller than that of the conventional path-trackers. Moreover, the average computation time of the proposed path-tracker is 12 milliseconds on a laptop equipped with an Intel i7-4710MQ CPU. It indicates that the proposed path tracker is ready for real-time implementation.

The continuous intake of 17β-estradiol (E2) residue from animal-derived food may pose a threat to the health of consumers, so the rapid screen and detection of E2 is very necessary. Although visual immunochromatographic strip (ICS) has played a great role in food safety control such as the screen of many food contaminants, it cannot meet the requirements for E2 detection due to the insufficient sensitivity of traditional visual ICS and the low concentration range of estrogen in food. Here, we developed a dual-mode ICS strategy to achieve rapid and highly sensitive detection of E2. Based on the visual detection mode of a competitive ICS, the afterglow detection mode working in fluorescence resonance energy transfer mechanism was introduced by using the afterglow particles (APs) as energy donor and gold nanoparticles (AuNPs) as energy acceptor. In this method, large APs of micron size with superior afterglow were applied as the test zone-fixed fluorescence signal source, thus the contradiction between migration and afterglow characteristics was skillfully resolved. In addition, a 6 W UV lamp was used as the light source to excite APs, and a smartphone was used to capture an image of 0.5 s after the UV light was turned off to effectively remove the autofluorescence from the strips and improve the signal-to-noise ratio. The limit of detection of this afterglow mode was 0.5 ng/mL, twenty times more sensitive than that of visual mode (10 ng/mL). The strategy has been successfully applied to the detection of estradiol in milk and verified by HPLC–FLD.

Consistent exposure to 17β-estradiol through drinking water and food can cause health problems. Although many simple and sensitive fluorescence sensors of 17β-estradiol have been reported, most of them are based on fluorescence quenching test mode working in visible light range, which are inferior in anti-interference ability and quantitative range. Here, we developed a near-infrared (NIR) phosphorescence aptasensor for the detection of 17β-estradiol that has no background fluorescence. The aptasensor was based on Foster resonance energy transfer (FRET) between aptamer conjugated NIR persistent luminescence nanoparticles (PLNPs-Apt) and MoS2 nanosheets. The 17β-estradiol was quantified by the recovery of PLNPs' phosphorescence. This assay can detect 17β-estradiol in 0.5 mL samples with the LOD of 0.29 ng mL-1 and in concentrations of more than three orders of magnitude (from 0.5 ng mL-1 to 1.2 μg mL-1). This aptasensor exhibited selectivity for 17β-estradiol and was applicable in complex milk samples.

Protein persulfidation is a newly defined oxidative posttranslational modification and plays important roles in many biological processes. Detection of protein persulfidation in living systems is urgently needed to advance the study of H2S/H2Sn-based signalling and cellular redox regulation. Here, we developed a novel off-on fluorescent probe for the detection of persulfidation using a chemical sensor, HQO-SSH, in biological systems. HQO-SSH features fast reaction, good selectivity and high sensitivity. Due to the distinctive features of HQO-SSH, this probe was successfully applied to image protein persulfidation changes in pulmonary cells. We also demonstrated that the probe is suitable for imaging protein persulfidation in lung tissues. In addition, confocal imaging with this method revealed that sulfur mustard, a commonly used chemical warfare agent, decreased mitochondrial protein persulfidation in living lung cells and tissues. Due to these results, this probe holds great promise for exploring the role of protein persulfidation in a variety of pathophysiological conditions.

Table S1. List of antibodies used in the study. (PDF 231 kb)

Figure S1. Evaluation of respiratory function. (PDF 298 kb)

Background Sulfur mustard (SM) is a notorious chemical warfare agent that can cause severe acute lung injury (ALI), in addition to other lesions. Currently, effective medical countermeasures for SM are lacking. Bone marrow-derived mesenchymal stromal cells (BMSCs) possess self-renewal and multipotent differentiation capacity. BMSCs can also migrate to inflammation and injury sites and exert anti-inflammatory and tissue repair functions. Here, we report the curative effect of BMSCs on SM-induced ALI in a mouse model. Methods Mice BMSCs were injected into mice via the tail vein 24 h after SM exposure. The distribution of BMSCs in mice was detected by fluorescence imaging. The therapeutic potential of BMSCs was evaluated by the calculating survival rate. The effects of BMSCs on lung tissue injury and repair assessment were examined by staining with H&E and measuring the lung wet/dry weight ratio, BALF protein level, and respiratory function. The effects of BMSCs on the infiltration and phenotypic alteration of inflammatory cells were analyzed by immunohistochemistry and flow cytometry. The levels of chemokines and inflammatory cytokines were examined using the Luminex Performance Assay and ELISA. RNA interference, western blotting, and ELISA were applied to explore the role of the TLR4 signaling pathway in the anti-inflammatory effects of BMSCs. The extent of tissue repair was analyzed by ELISA, western blotting, and immunohistochemistry. Results Fluorescence imaging indicated that the lung is the major target organ of BMSCs after injection. The injection of BMSCs significantly improved the survival rate (p

Sulfur mustard (SM) is a chemical warfare agent and a terrorism choice that targets various organs and tissues, especially lung tissues. Its toxic effects are tightly associated with oxidative stress. The signaling molecule hydrogen sulfide (H2S) protects the lungs against oxidative stress and activates the NF-E2 p45-related factor 2 (Nrf2) pathway. Here, we sought to establish whether endogenous H2S plays a role in SM induced lesion in mouse lungs and lung cells and whether endogenous H2S plays the role through Nrf2 pathway to protect against SM-induced oxidative damage. Furthermore, we also explored whether activation of Nrf2 by H2S involves sulfhydration of Kelch-like ECH-associated protein-1 (Keap1). Using a mouse model of SM-induced lung injury, we demonstrated that SM-induced attenuation of the sulfide concentration was prevented by NaHS. Concomitantly, NaHS attenuates SM-induced oxidative stress. We also found that H2S enhanced Nrf2 nuclear translocation, and stimulated expression of Nrf2-targeted downstream protein and mRNA levels. Incubation of the lung cells with NaHS decreased SM-induced ROS production. Furthermore, we also found that H2S S-sulfhydrated Keap1, which induced Nrf2 dissociation from Keap1, and enhanced Nrf2 nuclear translocation. Our data indicate that H2S is a critical, however, being long neglected signal molecule in SM-induced lung injury.

A novel water-soluble chitosan derivative, O -fumaryl-chitosan (OFCS), was prepared by using the selective partial acylation of chitosan and fumaric acid in the presence of H 2 SO 4 . The chemical structure and physical properties of OFCS were characterized by FTIR, 1 H NMR, 13 C NMR, and TG techniques. Our results showed that the degree of substitution (DS) for the chitosan derivatives was from 0.07 to 0.48 and the prepared derivatives had good solubility over a wide pH range, for example, the solubility of OFCS increased from 10.5 to 52.6 mg/ml as the DS increased. The antibacterial activity of chitosan and OFCS was investigated against Escherichia coli and Staphylococcus aureus . The results indicated that the antibacterial activity of OFCS was much stronger than that of chitosan and it increased with increasing DS increasing. These findings suggest that the OFCS with a DS of 0.48 is preferable for use as a food preservative.

To observe the law of the meridian abnormal changes and the correlation with acupuncture efficacy based on the effectiveness study of electroacupuncture (EA) in treatment of severe functional constipation.Seventy patients of severe functional constipation were randomized into an EA group and a sham-EA group, 35 cases in each one. In the EA group, Tianshu (ST 25) and Fujie (SP 14) were punctured deeply and stimulated with EA (dense-disperse wave, 2Hz/15 Hz, 0. 1 to 1. 0 mA), and Shangjuxu (ST 37) was needled. In the sham-EA group, the sites lateral to Tianshu (ST 25) and Fujie (SP 14) were punctured shallowly and stimulated with electricity. The site lateral to Shangjuxu (ST 37) was punctured shallowly. The treatment was given continuously for 8 weeks in the two groups, 5 times weekly in the first 2 weeks and 3 times weekly in the rest 6 weeks. WANG Juyi's meridian examination method was applied to detect the abnormalities of the spleen, stomach and large intestine meridians before treatment, and in 2, 4, 6 and 8 weeks among 70 patients separately. The frequency of complete spontaneous bowel movement (CSBM) every two weeks, meridian abnormal value and the relativity with CSBM change rate were compared in the patients between two groups.Regarding the increase of CSBM frequency, the effect started since the 2nd week in the EA group, with the treatment going on, CSBM frequency was increased apparently (all P0. 05). In the sham-EA group, after 6 and 8-weeks of treatment, CSBM frequency was increased apparently as compared with that before treatment (all P0. 05). The increase of CSBM frequency in the EA group was remarkably as compared with the sham-EA group at every time point (all P0. 05). The abnormal value of the large intestine meridian in 2 weeks of treatment and the values of the stomach and spleen meridians and the relevant meridians in 4 weeks of treatment were all reduced apparently as compared with those in the baseline in the EA group (all P0. 05). With the treatment time going on, the abnormal reflections on the large intestine and stomach meridians were reduced gradually (all P0. 05), and the total change rate of abnormalities on the large intestine, stomach and spleen meridians presented the negative correlation with the total change rate of CSBM frequency (P0. 01, P0. 05).In the EA group, the efficacy on CSBM frequency in severe functional constipation is advantageous and stable as compared with the sham-EA group. Acupuncture at the relevant acupoints of the spleen, stomach and large intestine meridians achieves the definite regulation to the meridian abnormalities. It is discovered that the abnormal changes in the spleen, stomach