A highly enantioselective sulfa‐Michael addition of tritylthiol to azadienes catalyzed by a bifunctional squaramide organocatalyst is described, giving the chiral aminothioethers bearing benzofuran ...motif with high yields and up to 94 % of enantioselectivity. Notably, the aromatization to form the benzofuran is the driving force.
Synthesis of aminothioether derivatives: A facile protocol for synthesis of the aminothioether derivatives through the bifunctional squaramide organocatalyst‐catalyzed asymmetric conjugate addition of thiols to azadienes is developed with excellent yields and up to 94 % of enantioselectivity.
An efficient method of synthesizing 2-trifluoromethylindoles from indoles with easy-to-handle, cheap and low-toxic CF3SO2Na under metal-free conditions is described, which selectively introduces ...trifluoromethyl to indoles on the C2 position. The desired product can be obtained in 0.7 g yield. A radical intermediate may be involved in this transformation.
Design, fabrication, and measurement of a new compact filter-antenna for modern wireless communication systems are presented in this letter. Two microstrip square open-loop resonators, a coupled ...line, and a Γ-shaped antenna are used and integrated to be a filter-antenna. The Γ-shaped antenna is excited by a coupled line that is treated as the admittance inverter in filter design. The Γ-shaped antenna performs not only a radiator, but also the last resonator of the bandpass filter. Therefore, near-zero transition loss is achieved between the filter and the antenna. The design procedure follows the circuit approach-synthesis of bandpass filters. Measured results show that the filter-antenna achieves an impedance bandwidth of 16.3% (over 2.26-2.66 GHz) at a reflection coefficient | S 11 | <; - 10 dB and has a gain of 2.41 dBi.
Exosomes have been considered as novel and potent vehicles of intercellular communication, instead of "cell dust". Exosomes are consistent with anucleate cells, and organelles with lipid bilayer ...consisting of the proteins and abundant lipid, enhancing their "rigidity" and "flexibility". Neighboring cells or distant cells are capable of exchanging genetic or metabolic information via exosomes binding to recipient cell and releasing bioactive molecules, such as lipids, proteins, and nucleic acids. Of note, exosomes exert the remarkable effects on lipid metabolism, including the synthesis, transportation and degradation of the lipid. The disorder of lipid metabolism mediated by exosomes leads to the occurrence and progression of diseases, such as atherosclerosis, cancer, non-alcoholic fatty liver disease (NAFLD), obesity and Alzheimer's diseases and so on. More importantly, lipid metabolism can also affect the production and secretion of exosomes, as well as interactions with the recipient cells. Therefore, exosomes may be applied as effective targets for diagnosis and treatment of diseases. Video abstract.
Severe fever with thrombocytopenia syndrome (SFTS) is a novel emerging viral infectious disease. We explore the value of cystatin C (CysC) level in the evaluation of disease severity and prognosis in ...patients with SFTS.
254 patients with SFTS were enrolled in this study. According to the classification and the outcome of the disease, the patients were divided into the general group and the severe group, the severe patients were divided into the fatal group and the non-fatal group. We compared the laboratory indexes by univariate and multivariate logistic regression analysis to explore the severity and prognostic risk factors of SFTS disease, ROC curve and Kaplan-Meier survival analysis curve were drawn to analyze the independent risk factors and the predictive value of disease severity and prognosis.
Univariate analysis showed that the CysC level in severe group and fatal group was significantly higher than general group and non-fatal group (P < 0.05), respectively. Multivariate logistic regression showed that the CysC level was an independent risk factor for severe and death in SFTS patients, and it can effectively predict the risk of severe (AUC = 0.711, 95% CI: 0.645-0.777) and death (AUC = 0.814, 95% CI: 0.737-0.89). The risk of death in patients with cystatin C ≥ 1.23 mg/L was 5.487 times higher than that in patients with cystatin C < 1.23 mg/L.
The CysC level have good predictive value for disease severity and prognosis in patients with SFTS. Trial registration Not applicable.
The health risks and toxicity of heavy metals (HMs) in PM2.5 are not only associated with their total amounts, but also with their species and bioaccessibility. In this study, the speciation ...(fractions) and bioaccessibility of HMs (Pb, Cd, Cr, Cu and Zn) as well as their correlations in fine particulate matter (PM2.5) samples from four seasons were studied. A sequential extraction procedure was applied to divide the studied HMs into four fractions: acid-soluble fraction (F1), reducible fraction (F2), oxidative fraction (F3) and residual fraction (F4). The simulated body fluids (gastrointestinal and lung phases) were used for in vitro tests in order to evaluate the bioaccessibility of HMs. The distribution of HMs in PM2.5 was season and element dependent. It was found that Zn was the most abundant element among the five measured metals and followed by Pb, Cu, Cr and Cd. The total contents of each HM in different seasons were in the following order: winter > autumn > spring > summer. The studied HMs were mainly concentrated in acid-soluble fraction (F1) with high bioaccessibility (p < 0.05) except for Cr. Zn, Pb and Cu possessed the highest bioaccessibility in summer while Cd and Cr were the highest in winter. In vitro tests indicated that HMs in PM2.5 were much more accessible to gastrointestinal fluids rather than lung phase (Gamble's solution). A significant correlation was found between the results from the optimized BCR sequential extraction and solubility bioaccessibility research consortium (SBRC). The fractions extracted by SBRC were consistent with the first two fractions extracted by the sequential extraction method.
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•BCR sequential extraction and in vitro test were used to study HMs in PM2.5.•Pb, Cd, Cu and Zn in PM2.5 were mainly existed in F1 with high bioaccessibility.•Bioaccessibility and speciation of HMs in PM2.5 varied with different seasons.•Correlation was found between BCR sequential extraction and SBRC method.
High bioaccessibility of HMs in PM2.5 and the significant correlation of SBRC/BCR sequential extraction were discovered.
•Yellow or green spots on peels with oleocellosis were related to pigment changes.•Changes in chlorophyll and carotenoids were probed by a microplate reader and HPLC.•Gene expression involved in ...pigment metabolism was measured by RNA-Seq technology.•Changes in pigments and related genes expression were found in oleocellosis peels.
Yellow or green spots related to pigment changes found at the early stage of oleocellosis can cause severe economic damage. However, little information exists on pigment changes during oleocellosis development, so this study investigated the main changes in chlorophyll and carotenoid metabolites and related gene expression. Among the variations, the increased contents of chlorophyll a and b, and decreased concentrations of lutein, β-cryptoxanthin, zeaxanthin, violaxanthin, α-carotene and β-carotene were responsible for chlorophyll and carotenoid changes, respectively. Regarding gene expression, the up-regulated genes, magnesium chelatase subunit H (MgCh), magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase 1/2 (MPEC1/2), protochlorophyllide reductase a, chloroplastic 1/2 (PORA1/2) and chlorophyllide a oxygenase (CAO), regarding chlorophyll synthesis as well as the down-regulated genes, phytoene synthase (PSY), phytoene dehydrogenase (PDS), lycopene β-cyclase (LCYb), and zeaxanthin epoxidase 1/2 (ZEP 1/2) and the up-regulated genes (+)-abscisic acid 8′-hydroxylase 1/2 (ABA-HX 1/2), regarding carotenoid metabolism, constituted the major variations in oleocellosis peels.
Binary metallic organic frameworks can always play excellent functions for pollutants removal. One binary MOFs, UiO-66(Fe/Zr)), was newly synthesized and applied to remove aquatic selenite (SeIV) and ...selenate (SeVI). The adsorption behaviors and mechanisms were investigated using batch experiments, spectroscopic analyses, and theoretical calculations (DFT). The characterization results showed that the material inherited the topological structure of UiO-66 and excellent thermal stability. The large specific surface area (467.52 m2/g) and uniform mesoporous structures of the synthesized MOFs resulted in fast adsorption efficiency and high adsorption capacity for selenium species. The adsorbent kept high adsorption efficiency in a wide pH range from 2 to 11 with good anti-interference ability. The maximum adsorption capacity for Se(IV) and Se(VI) reached as high as 196 mg/g at pH 3 and 258 mg/g at pH 5, respectively. The process was conformed to fit pseudo-second-order kinetics and Langmuir isotherm, and could be explained by the formation of Fe/Zr-O-Se bond on the material surface, which was interpreted by the results of XPS, FTIR and DFT calculation. The regeneration and TCLP experiments demonstrated that UiO-66(Fe/Zr) could be regenerated for five cycles without obvious decrease of efficiencies, and the leaching rate of the adsorbed Se(IV) and Se(VI) in the spent adsorbent were only 4.8% and 2.3%. More than 99% of original Se(IV) and Se(VI) in the lake and tap water samples (1.0 mg/L of Se) could be removed in 2.0 h.
•A binary UiO-66(Fe/Zr) was synthesized and applied to remove aquatic Se(IV) and Se(VI) with good stability.•The combination of Fe/Zr bimetallic nodes contributed to the exceptional adsorption capacities for Se(VI).•The adsorbent played excellent performances in a wide pH range with good anti-interference ability.•The selenium species could be immobilized on the adsorbent with very low leaching ratio.
Radix Astragali
(AR) is a commonly used medicinal herb for post-stroke disability in Traditional Chinese Medicine but its active compounds for promoting neurogenic effects are largely unknown. In the ...present study, we tested the hypothesis that
Astragaloside VI
could be a promising active compound from AR for adult neurogenesis and brain repair via targeting epidermal growth factor (EGF)-mediated MAPK signaling pathway in post-stroke treatment. By using cultured neural stem cells (NSCs) and experimental stroke rat model, we investigated the effects of
Astragaloside VI
on inducing NSCs proliferation and self-renewal in vitro, and enhancing neurogenesis for the recovery of the neurological functions in post-ischemic brains in vivo. For animal experiments, rats were undergone 1.5 h middle cerebral artery occlusion (MCAO) plus 7 days reperfusion.
Astragaloside VI
(2 μg/kg) was daily administrated by intravenous injection (i.v.) for 7 days.
Astragaloside VI
treatment promoted neurogenesis and astrogenic formation in dentate gyrus zone, subventricular zone, and cortex of the transient ischemic rat brains in vivo.
Astragaloside VI
treatment enhanced NSCs self-renewal and proliferation in the cultured NSCs in vitro without affecting NSCs differentiation. Western blot analysis showed that
Astragaloside VI
up-regulated the expression of nestin, p-EGFR and p-MAPK, and increased neurosphere sizes, whose effects were abolished by the co-treatment of EGF receptor inhibitor gefitinib and ERK inhibitor PD98059. Behavior tests revealed that
Astragaloside VI
promoted the spatial learning and memory and improved the impaired motor function in transient cerebral ischemic rats. Taken together,
Astragaloside VI
could effectively activate EGFR/MAPK signaling cascades, promote NSCs proliferation and neurogenesis in transient cerebral ischemic brains, and improve the repair of neurological functions in post-ischemic stroke rats.
Astragaloside VI
could be a new therapeutic drug candidate for post-stroke treatment.
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