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Mesenchymal stromal cells (MSCs) have long been considered a potential tool for treatment of allergic inflammatory diseases, owing to their immunomodulatory characteristics. In recent decades, the medical utility of MSCs has been evaluated both in vitro and in vivo, providing a foundation for therapeutic applications. However, the existing limitations of MSC therapy indicate the necessity for novel therapies. Notably, small extracellular vesicles (sEV) derived from MSCs have emerged rapidly as candidates instead of their parental cells. The acquisition of abundant and scalable MSC‐sEV is an obstacle for clinical applications. The potential application of MSC‐sEV in allergic diseases has attracted increasing attention from researchers. By carrying biological microRNAs or active proteins, MSC‐sEV can modulate the function of various innate and adaptive immune cells. In this review, we summarise the recent advances in the immunomodulatory properties of MSCs in allergic diseases, the cellular sources of MSC‐sEV, and the methods for obtaining high‐quality human MSC‐sEV. In addition, we discuss the immunoregulatory capacity of MSCs and MSC‐sEV for the treatment of asthma, atopic dermatitis, and allergic rhinitis, with a special emphasis on their immunoregulatory effects and the underlying mechanisms of immune cell modulation. [ABSTRACT FROM AUTHOR]

The microwave digestion method can be used for most coal samples, but not for those with ultra-high organic matter because they contain multiple complex high molecular organisms due to the high coalification degree and cannot be digested by digestion techniques currently available. In this paper, the conditions for microwave digestion including digestion reagents, temperature and time were investigated. The digestion system suitable for anthracite with high organic content was investigated and the feasibility on determination of total Hg and As by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) was investigated. Results show that using nitric acid-sulfuric acid-hydrofluoric acid (6:4:0.5) as the digestion reagent and the digestion temperature of 205℃ for 30 minutes, the anthracite with high organic content can be completely digested due to the key role of sulfuric acid. The detection results of mercury by HG-AFS and ICP-MS were consistent, both recoveries of which reach more than 98%. The result of arsenic by HG-AFS was significantly lower due to incomplete transformation of organic As to inorganic As. Therefore, anthracite with high organic content (81%-90%) can be completely digested to solution by microwave technique, and Hg and As can be determined by ICP-MS. HG-AFS is not an efficient method to analyze mercury.

Mesenchymal stromal cells (MSCs) are well known for their immunoregulatory roles on allergic inflammation particularly by acting on T cells, B cells, and dendritic cells (DCs). MSC‐derived small extracellular vesicles (MSC‐sEV) are increasingly considered as one of the main factors for the effects of MSCs on immune responses. However, the effects of MSC‐sEV on DCs in allergic diseases remain unclear. MSC‐sEV were prepared from the induced pluripotent stem cells (iPSC)‐MSCs by anion‐exchange chromatography, and were characterized with the size, morphology, and specific markers. Human monocyte‐derived DCs were generated and cultured in the presence of MSC‐sEV to differentiate the so‐called sEV‐immature DCs (sEV‐iDCs) and sEV‐mature DCs (sEV‐mDCs), respectively. The phenotypes and the phagocytic ability of sEV‐iDCs were analyzed by flow cytometry. sEV‐mDCs were co‐cultured with isolated CD4+T cells or peripheral blood mononuclear cells (PBMCs) from patients with allergic rhinitis. The levels of Th1 and Th2 cytokines produced by T cells were examined by ELISA and intracellular flow staining. And the following mechanisms were further investigated. We demonstrated that MSC‐sEV inhibited the differentiation of human monocytes to iDCs with downregulation of the expression of CD40, CD80, CD86, and HLA‐DR, but had no effects on mDCs with these markers. However, MSC‐sEV treatment enhanced the phagocytic ability of mDCs. More importantly, using anti‐IL‐10 monoclonal antibody or IL‐10Rα blocking antibody, we identified that sEV‐mDCs suppressed the Th2 immune response by reducing the production of IL‐4, IL‐9, and IL‐13 via IL‐10. Furthermore, sEV‐mDCs increased the level of Treg cells. Our study identified that mDCs treated with MSC‐sEV inhibited the Th2 responses, providing novel evidence of the potential cell‐free therapy acting on DCs in allergic airway diseases. [ABSTRACT FROM AUTHOR]

Energy storage provides sustainable energy. Magnesium hydroxide (Mg(OH)2) is a promising material for thermochemical energy storage. Zirconium oxynitrate (ZrO(NO3)2) and lithium hydroxide (LiOH) are investigated to improve the heat‐storage efficiency of Mg(OH)2. Experimental results indicate that the heat‐storage rate can be significantly increased by 306‐fold. The dehydration conversion can be increased up to 99% with 122‐fold increase in 15.3 min. The onset temperature of Mg(OH)2 dehydration decreases from 337 to 228°C. The activation energy of Mg(OH)2 dehydration significantly reduces by 57.7%. The cycle ability of heat storage and heat release also remarkably improves. Moreover, the heat‐storage time significantly decreases. The crystal parameters, crystal volume, and platelet size of Mg(OH)2 notably diminish. The acting mechanism of these additives is proposed using high‐resolution transmission electron microscopy, X‐ray powder diffraction, and X‐ray photoelectron spectroscopy data. Moreover, the kinetic equations for the dehydration of excellent Mg(OH)2 composites are disclosed for computing simulation. [ABSTRACT FROM AUTHOR]

Group 2 innate lymphoid cells (ILC2s) are recognized as key controllers and effectors of type 2 inflammation. Mesenchymal stem cells (MSCs) have been shown to alleviate type 2 inflammation by modulating T lymphocyte subsets and decreasing TH2 cytokine levels. However, the effects of MSCs on ILC2s have not been investigated. In this study, we investigated the potential immunomodulatory effects of MSCs on ILC2s in peripheral blood mononuclear cells (PBMCs) from allergic rhinitis patients and healthy subjects. We further investigated the mechanisms involved in the MSC modulation using isolated lineage negative (Lin−) cells. PBMCs and Lin− cells were cocultured with induced pluripotent stem cell‐derived MSCs (iPSC‐MSCs) under the stimulation of epithelial cytokines IL‐25 and IL‐33. And the ILC2 levels and functions were examined and the possible mechanisms were investigated based on regulatory T (Treg) cells and ICOS‐ICOSL pathway. iPSC‐MSCs successfully decreased the high levels of IL‐13, IL‐9, and IL‐5 in PBMCs in response to IL‐25, IL‐33, and the high percentages of IL‐13+ILC2s and IL‐9+ILC2s in response to epithelial cytokines were significantly reversed after the treatment of iPSC‐MSCs. However, iPSC‐MSCs were found directly to enhance ILC2 levels and functions via ICOS‐ICOSL interaction in Lin− cells and pure ILC2s. iPSC‐MSCs exerted their inhibitory effects on ILC2s via activating Treg cells through ICOS‐ICOSL interaction. The MSC‐induced Treg cells then suppressed ILC2s by secreting IL‐10 in the coculture system. This study revealed that human MSCs suppressed ILC2s via Treg cells through ICOS‐ICOSL interaction, which provides further insight to regulate ILC2s in inflammatory disorders. [ABSTRACT FROM AUTHOR]

As a key element of ITS (intelligent traffic systems), traffic information collection facilities play a key role, with ITS being able to analyze the state of mixed traffic more appropriately and can provide effective technical support for the design, management, and the evaluation of constructions. Traffic Infrastructure. Focusing on image processing technology, this study takes pedestrians, electric motor, and vehicles in mixed traffic flow as the research object, and Gaussian mixed model, Kalman filtering, and Fisher linear discriminant are introduced in the recognition system. On this basis, the mixed motion flow data acquisition framework model is elaborated in detail, which includes attribute extraction, object recognition, and object tracking. Given the difficulty in capturing reliable images of objects in real traffic scenes, this study adopted a novel background and foreground classification method with region proposal network so as to decrease the number of regions proposal from 2000 to 300, which can detect objects fast and accurately. Experiments demonstrate that the designed programme can collect the flow data by detecting and tracking moving object in the surveillance video for mixed traffic. Further integration of various modules to achieve integrated collection is another important task for further research and development. In the future, research on dynamic calibration of monocular vision will be carried out for distance measurement and speed measurement of vehicles and pedestrians. [ABSTRACT FROM AUTHOR]

Group 2 innate lymphoid cells (ILC2s) are recently reported to play a more critical role in allergic diseases. We previously identified that mesenchymal stromal cells (MSCs) elicited therapeutic effects on allergic airway inflammation. Small extracellular vesicles (sEV) derived from MSCs possess striking advantages including low immunogenicity and high biosafety, and is extremely promising cell-free therapeutic agents. However, the effects of MSC-sEV on ILC2s are still unclear. Additionally, scalable isolation protocols are required for the mass production of homogenous MSC-sEV especially in clinical application. We previously reported that induced pluripotent stem cells-derived MSCs were the ideal cellular source for the large preparation of MSC-sEV. Here we developed a standardized scalable protocol of anion-exchange chromatography for isolation of MSC-sEV, and investigated the effects of MSC-sEV on ILC2 function from patients with allergic rhinitis and in a mouse ILC2-dominant asthma model. The characterization of MSC-sEV was successfully demonstrated in terms of size, morphology and specific markers. Using flow cytometry and human Cytokine Antibody Array, MSC-sEV but not fibroblasts-sEV (Fb-sEV) were found to significantly inhibit the function of human ILC2s. Similarly, systemic administration of MSC-sEV but not Fb-sEV exhibited an inhibition of ILC2 levels, inflammatory cell infiltration and mucus production in the lung, a reduction in levels of T helper 2 cytokines, and alleviation of airway hyperresponsiveness in a mouse model of asthma. Using RNA sequencing, miR-146a-5p was selected as the candidate to mediate the above effects of MSC-sEV. We next revealed the uptake of ILC2s to MSC-sEV, and that transfer of miR-146a-5p in MSC-sEV to ILC2s in part contributed to the effects of MSC-sEV on ILC2s in vitro and in a mouse model. In conclusion, we demonstrated that MSC-sEV were able to prevent ILC2-dominant allergic airway inflammation at least partially through miR-146a-5p, suggesting that MSC-sEV could be a novel cell-free strategy for the treatment of allergic diseases. [ABSTRACT FROM AUTHOR]

A sequential multistep reaction toward 5-thio- or 5-selenotriazoles has been established by generation of both copper(I) triazolides and sulfenylating or selenylating agents in situ, starting from elemental sulfur or selenium. This reaction features mild conditions, readily available and broad-scope substrates, good functional group compatibility, high efficiency and regioselectivity, easy operation, and ligand-free CuI. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the association between methylation of DNA damage response-related genes such as cyclin-dependent kinase inhibitor (CDKN) 2A , Ras association (RalGDS/AF-6) domain family member (RASSF) 1A , O6-methylguanine DNA methyltransferase (MGMT), Kirsten rat sarcoma viral oncogene homolog (KRAS), and spleen-associated tyrosine kinase (SYK) and DNA damage in hepatocytes of rats following subchronic exposure to vinyl chloride (VC). Sixty-four healthy rats were randomly divided into three VC exposure groups (5, 25, and 125 mg/kg) and an untreated negative control group (n = 16 each). VC was administered by intraperitoneal injection every other day for a total of three times a week. Eight randomly selected rats from each group were sacrificed at the end of 6 and 12 weeks, and liver tissue was harvested for the comet assay and for assessment of DNA methylation level and mRNA expression of related genes by PCR. Overall methylation levels in the genome of hepatocytes in VC-exposed rats were higher than those in the control group at 6 and 12 weeks (P < 0.05), although no differences were observed with regarding to dose (P > 0.05). After 12 weeks of exposure, differences in the methylation of RASSF1A and MGMT promoter regions were observed between the high-dose group and other groups (P < 0.05), whereas no differences were observed for the KRAS , SYK , and CDKN2A promoters (P > 0.05). These results suggest that DNA damage and increased genome-wide methylation are biomarkers for VC exposure and that RASSF1A and MGMT promoter methylation is related to the carcinogenic mechanism of VC. • Vinyl chloride (VC) exposure increased overall methylation levels in rat hepatocytes. • DNA damage and increased genome-wide methylation are biomarkers for VC exposure. • RASSF1A promoter hyper-methylation is related to the DNA damage induced by VC. [ABSTRACT FROM AUTHOR]

Two intermediates, 1,5-dinitroso-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DNDS) and 1-nitroso-3,5,7-trinitro-1,3,5,7-tetraazacyclooctane (MNX), were isolated and characterized in the synthesis of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) from the nitrolysis of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3,3,1]nonane (DPT) for the first time. When the nitrolysis of DPT was slowed down, two intermediates were detected with HPLC. It was proposed that electrophilic NO2+ and NO+ from HNO3 and N2O4 might attack nitrogen atoms at positions 3 and 7 of DPT to form the cations of the intermediates, then nucleophilic H2O attacked the bridge carbon atoms of DPT to produce the intermediates, which were oxidized to form HMX. [ABSTRACT FROM AUTHOR]

Insect glutathione S-transferases (GSTs) play important roles in detoxifying toxic compounds and eliminating oxidative stress caused by these compounds. In this study, detoxification activity of the epsilon GST SlGSTE1 in Spodoptera litura was analyzed for several insecticides and heavy metals. SlGSTE1 was significantly up-regulated by chlorpyrifos and xanthotoxin in the midgut of S. litura. The recombinant SlGSTE1 had Vmax (reaction rate of the enzyme saturated with the substrate) and Km (michaelis constant and equals to the substrate concentration at half of the maximum reaction rate of the enzyme) values of 27.95 ± 0.88 μmol/min/mg and 0.87 ± 0.028 mmol/L for glutathione, respectively, and Vmax and Km values of 22.96 ± 0.78 μmol/min/mg and 0.83 ± 0.106 mmol/L for 1-chloro-2,4-dinitrobenzene, respectively. In vitro enzyme indirect activity assay showed that the recombinant SlGSTE1 possessed high binding activities to the insecticides chlorpyrifos, deltamethrin, malathion, phoxim and dichloro-diphenyl-trichloroethane (DDT). SlGSTE1 showed higher binding activity to toxic heavy metals cadmium, chromium and lead than copper and zinc that are required for insect normal growth. Western blot analysis showed that SlGSTE1 was induced in the gut of larvae fed with chlorpyrifos or cadmium. SlGSTE1 also showed high peroxidase activity. All the results together indicate that SlGSTE1 may play an important role in the gut of S. litura to protect the insect from the toxic effects of these compounds and heavy metals. [ABSTRACT FROM AUTHOR]

N-heterocyclic compounds are key nitration precursors for some high energy density explosives such as 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX). Nitration of 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) yields HMX in high yields and purity. However, the analogue 1,3,5-triacetyl-1,3,5-triazacyclohexane (TRAT) is easily co-produced via the condensation of acetonitrile and 1,3,5-trioxan. To selectively extract TAT from a mixture of TAT and TRAT, the molecular imprinting technology (MIT) was developed in this study. The capacity of the dry polymer is 16 mg g−1 and the recovery surpasses 75 %. [ABSTRACT FROM AUTHOR]

A novel method for synthesizing carfentanil is researched in this work. N-Boc-protected piperidinone was used as the starting material. The carfentanil was achieved via synthetic rout involving five steps: Bargellini reaction, N-acylation, methylation, deprotection and N-alkylation. The overall yield of target compound was 31. 6%. The structures of intermediates and final product were determined by infrared spectroscopy, nuclear magnetic resonance spectroscopy and mass spectrograph. [ABSTRACT FROM AUTHOR]

Additive, dominance genetic effects were analysed for body weight (BW) and seven morphometric traits from three variants of red common carp, Cyprinus carpio var. singuonensis, C. carpio var. wuyuanensis and C. carpio var. color, based on a diallel cross-mating design by using the additive–dominance genetic model. The results indicated that at 8 months of age (juvenile stage), the traits of pre-dorsal height (PDH), pre-dorsal width (PDW) and caudal peduncle height (CPH) were mainly controlled by additive effects; the traits of BW, total length (TL), standard length (SL), head length (HL) and caudal peduncle length (CPL) were mainly controlled by dominance effects. The narrow-sense heritabilities of all traits ranged from 0.000 to 0.556; however, the broad-sense heritabilities ranged from 0.453 to 0.775. At 20 months of age (adult stage), the traits of TL, SL, PDH and CPL were mainly controlled by additive effects, whereas the traits of BW, PDW, HL and CPH were mainly controlled by dominance effects. The narrow-sense heritabilities of all traits ranged from 0.000 to 0.710; the broad-sense heritabilities ranged from 0.629 to 0.934. Through the genetic merit prediction from three parents, it was found that the additive and dominance effects of C. carpio var. color could increase the BW and body length in their progeny, but these two genetic effects of C. carpio var. singuonensis and C. carpio var. wuyuanensis could decrease BW in their progeny. The genetic effects of C. carpio var. wuyuanensis could reduce total length, SL and caudal peduncle length, but increase body height in their progeny. [ABSTRACT FROM AUTHOR]

This paper studies two-step synthetic process of TEX (4,10-dinitro-2,6, 8,12-tetraoxa-4, 10-diazatetracyclo-[5. 5. 0. 05,9 03,11]-dodecane) and the effects of key factors on the yield of DFTHP (intermediate) and TEX. The results show that the yield of DFTHP could reach to 68. 3% when the adjusted pH value of reaction solution reaches to 9 by saturated NaOH solution. When the volume ratio of fuming HNO3 to concentrated H2SO4 is 3 : 2, and the ratio of nitrating agent (mL) to DFTHP(g) is 3 : 1, the yield of TEX raises to 59. 7% . The optimized overall yield of TEX obtained from two-step synthetic process could be 40. 8%. [ABSTRACT FROM AUTHOR]

The worldwide threat from tuberculosis (TB) has resulted in great demand for new drugs, particularly those that can treat multidrug-resistant TB. We synthesized novel pleuromutilin derivatives with N -benzylamine side chain substituted at the C14 position and evaluated their activity in vitro against a virulent strain of Mycobacterium tuberculosis (H37Rv). The primary assay results showed that five compounds inhibited the H37Rv at 20 μM, with a MIC of one of the analogues as low as 7.2 μM. [ABSTRACT FROM AUTHOR]