In this work, a sulfate radical (SO4-)-based advanced oxidation process was applied to the degradation of sulfamethoxazole (SMX). In these experiments, a medium pressure UV (MPUV) lamp was employed ...to active peroxymonosulfate (PMS). It was found that 98% of SMX was removed by MPUV/PMS at a UV dose of 200 mJ cm−2 (3.95 μM SMX, 0.2 mM PMS, pH0 = 3.7). Direct MPUV photolysis played a remarkable role in SMX removal by MPUV/PMS process. As for the indirect photolysis, SO4- was the major reactive species under acidic and neutral conditions in MPUV/PMS system, while the hydroxyl radical (OH) became the predominant radical under alkaline conditions. The transformation products (TPs) of SMX that formed in the MPUV-only and MPUV/PMS experiments were identified, and the possible degradation pathways were proposed. Photoisomerization of the isoxazole ring was the major pathway of SMX during MPUV-only process. Hydroxylation/oxidation of the aniline and isoxazole ring was the predominant degradation mechanism of SMX by MPUV/PMS. Toxicity evaluation showed that MPUV/PMS was effective at reducing the antibacterial activity of SMX solutions, while MPUV-only was not. However, some TPs with equivalent or even higher antibacterial activity than SMX were formed during the initial degradation period in MPUV/PMS system. Ecotoxicity of SMX and its TPs was also hypothetically predicted via the ECOSAR program, and the results indicated that some TPs could be more toxic than SMX.
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•MPUV activated PMS oxidation was effective for SMX removal.•Initial transformation mechanisms were proposed based on the products identified by UPLC-Q-TOF.•MPUV/PMS was effective to reduce the antibacterial activity of SMX solutions.•ECOSAR analysis shows that some harmful products were produced.
A total of thirty-three strains of Bacillus were isolated from sixteen samples of naturally fermented congee in Inner Mongolia of China and identified by 16S rDNA sequence analysis. Probiotic ...properties including acid, bile tolerance and artificial gastrointestinal juice resistance as well as inhibition on pathogenic bacteria were used for screening of Bacillus. After the preliminary selection, four strains including Bacillus licheniformis IMAUB1002, Bacillus subtilis IMAUB1011, Bacillus amyloliquefaciens IMAUB1014 and Bacillus amyloliquefaciens IMAUB1034 showed high tolerance to simulated gastric juice at pH 2.0 for 3 h with survival rate all above 92%. And then through gastrointestinal transit, survival rates of these four strains were above 90%. Furthermore, Bacillus licheniformis IMAUB1002 performed well in tolerance to bile salt (0.6%) and inhibitory activity to five food-borne pathogens among four strains of Bacillus. The results suggested that Bacillus licheniformis IMAUB1002 should be considered as a potential probiotics. Further study will be focused on evaluation of these porbiotics properties in vivo and clarification of its other functional properties so as to use it in functional foods production in future.
Diamond anvil cell techniques have been improved to allow access to the multimegabar ultrahigh-pressure region for exploring novel phenomena in condensed matter. However, the only way to determine ...crystal structures of materials above 100 GPa, namely, X-ray diffraction (XRD), especially for low Z materials, remains nontrivial in the ultrahigh-pressure region, even with the availability of brilliant synchrotron X-ray sources. In this work, we perform a systematic study, choosing hydrogen (the lowest X-ray scatterer) as the subject, to understand how to better perform XRD measurements of low Z materials at multimegabar pressures. The techniques that we have developed have been proved to be effective in measuring the crystal structure of solid hydrogen up to 254 GPa at room temperature C. Ji et al., Nature 573, 558–562 (2019). We present our discoveries and experiences with regard to several aspects of this work, namely, diamond anvil selection, sample configuration for ultrahigh-pressure XRD studies, XRD diagnostics for low Z materials, and related issues in data interpretation and pressure calibration. We believe that these methods can be readily extended to other low Z materials and can pave the way for studying the crystal structure of hydrogen at higher pressures, eventually testing structural models of metallic hydrogen.
In this study, we provide the first comprehensive annotation of canine interferon-λ (CaIFN-λ, type III IFN). Phylogenetic analysis based on genomic sequences indicated that CaIFN-λ is located in the ...same branch with Swine IFN-λ1 (SwIFN-λ), Bat IFN-λ1 (BaIFN-λ), and human IFN-λ1 (HuIFN-λ1). CaIFN-λ was cloned, expressed in Escherichia coli, and purified to further investigate the biological activity in vitro. The recombinant CaIFN-λ (rCaIFN-λ) displayed potent antiviral activity on both homologous and heterologous animal cells in terms of inhibiting the replication of the New Jersey serotype of vesicular stomatitis virus (VSV), canine parvovirus, and influenza virus A/WSN/33 (H1N1), respectively. In addition, we also found that rCaIFN-λ exhibits a significant antiproliferative response against A72 canine tumor cells and MDCK cells in a dose-dependent manner. Furthermore, CaIFN-λ activated the JAK-STAT signaling pathway. To evaluate the expression of CaIFN-λ induced by virus and the expression of IFN-stimulated genes (ISGs) induced by rCaIFN-λ in the MDCK cells, we measured the relative mRNA level of CaIFN-λ and ISGs (ISG15, Mx1, and 2'5'-OAS) by quantitative real-time PCR and found that the mRNA level of CaIFN-λ and the ISGs significantly increased after treating the MDCK cells with viruses and rCaIFN-λ protein, respectively. Finally, to evaluate the binding activity of rCaIFN-λ to its receptor, we expressed the extracellular domain of the canine IFN-λ receptor 1 (CaIFN-λR1-EC) and determined the binding activity via ELISA. Our results demonstrated that rCaIFN-λ bound tightly to recombinant CaIFN-λR1-EC (rCaIFN-λR1-EC).
The nucleoprotein (NP) of influenza A virus is a multifunctional protein that plays a critical role in the replication and transcription of the viral genome. Therefore, examining host factors that ...interact with NP may shed light on the mechanism of host restriction barriers and the tissue tropism of influenza A virus. Here, Cyclophilin E (CypE), a member of the peptidyl-propyl cis-trans isomerase (PPIase) family, was found to bind to NP and inhibit viral replication and transcription.
In the present study, CypE was found to interact with NP but not with the other components of the viral ribonucleoprotein complex (VRNP): PB1, PB2, and PA. Mutagenesis data revealed that the CypE domain comprised of residues 137-186 is responsible for its binding to NP. Functional analysis results indicated that CypE is a negative regulator in the influenza virus life cycle. Furthermore, knock-down of CypE resulted in increased levels of three types of viral RNA, suggesting that CypE negatively affects viral replication and transcription. Moreover, up-regulation of CypE inhibited the activity of influenza viral polymerase. We determined that the molecular mechanism by which CypE negatively regulates influenza virus replication and transcription is by interfering with NP self-association and the NP-PB1 and NP-PB2 interactions.
CypE is a host restriction factor that inhibits the functions of NP, as well as viral replication and transcription, by impairing the formation of the vRNP. The data presented here will help us to better understand the molecular mechanisms of host restriction barriers, host adaptation, and tissue tropism of influenza A virus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Lactobacilli are considered to be one of the most important potential probiotics in the dairy industry. Twelve strains of Lactobacillus were isolated from home-made koumiss samples, a traditionally ...fermented mare milk in China. The isolates were identified based on physiological and biochemical characteristics and analysis of 16S RNA sequences. They were proven to be Lactobacillus helveticus, Lactobacillus fermentum, Lactobacillus casei and Lactobacillus plantarum. The results demonstrated that both methods were essential to identify an isolate accurately.
We would like to take this opportunity to thank all of Materials Chemistry Frontiers ’ reviewers for helping to preserve quality and integrity in chemical science literature. We would also like to ...highlight the Outstanding Reviewers for Materials Chemistry Frontiers in 2023.
Desalinated seawater containing bromide ion (Br−) blended with drinking water may produce brominated disinfection byproducts (Br-DBPs) during chlorination, which would pose a potential threat to ...human health when incorporated into the municipal water supply system. This study investigated the formation and speciation of twenty-one DBPs during chlorination in two desalinated seawater blends, i.e., treated drinking water blended with reverse osmosis (RO) permeate and post-treatment (PT) product water. After chlorination, the number and concentrations of DBPs formed in the desalinated seawater obviously enhanced, with chlorinated DBPs (Cl-DBPs) dominating. Sixteen DBPs were found in both RO and PT blends samples during chlorination, in which haloacetic acids (HAAs) had the highest concentration, followed by trihalomethanes (THMs) and halogen acetonitriles (HANs). When the volume of desalinated seawater in the blends was increased, the transformation from Cl-DBPs to Br-DBPs was observed for THMs and HANs, indicating that Br− was more easily incorporated into THMs and HANs than HAAs. Additionally, more Br− participated in the DBPs formation per unit dissolved organic carbon and Br-DBPs/DBPs increased, when the blended ratio of the desalinated seawater increased. The DBP-associated toxicity in the blends was estimated based on the toxicity-weighted concentration with Br-HANs as the predominant contributor, followed by Cl-HAAs.
•Cl-DBPs were the dominant DBPs during chlorination for desalinated seawater and blends.•PT blends showed higher water quality stability than RO blends.•With blended ratios (RO or PT) increasing, DBPs decreased and Br-DBPs/DBPs increased.•Bromide ions were more easily incorporated into THMs and HANs than HAAs.•Br-HANs were the predominant contributor to the DBP-associated toxicity in the blends.
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