With the enhancement of copper (Cu) stress, the germination percentage of wheat seeds decreased gradually. Pretreatment with sodium hydrosulfide (NaHS), hydrogen sulfide (H₂S) donor alleviated the ...inhibitory effect of Cu stress in a dose-dependent manner; whereas little visible symptom was observed in germinating seeds and radicle tips cultured in NaHS solutions. It was verified that H₂S or HS⁻ rather than other sulfur-containing components derived from NaHS attribute to the potential role in promoting seed germination against Cu stress. Further studies showed that NaHS could promote amylase and esterase activities, reduce Cu-induced disturbance of plasma membrane integrity in the radicle tips, and sustain lower levels of malondialdehyde and H₂O₂ in germinating seeds. Furthermore, NaHS pretreatment increased activities of superoxide dismutase and catalase and decreased that of lipoxygenase, but showed no significant effect on ascorbate peroxidase. Alternatively, NaHS prevented uptake of Cu and promoted the accumulation of free amino acids in seeds exposed to Cu. In addition, a rapid accumulation of endogenous H₂S in seeds was observed at the early stage of germination, and higher level of H₂S in NaHS-pretreated seeds. These data indicated that H₂S was involved in the mechanism of germinating seeds' responses to Cu stress.
Benzalkonium chlorides (BACs), as typical cationic surfactants and biocides widely applied in household and industrial products, have been frequently detected as micropollutants in many aquatic ...environments. In this study, the combination of UV irradiation and chlorine (UV/chlorine), a newly interested advanced oxidation process, was used to degrade dodecylbenzyldimethylammonium chloride (DDBAC). UV/chlorine showed synergistic effects on DDBAC degradation comparing to UV irradiation or chlorination alone. Radical quenching experiments indicated that degradation of DDBAC by UV/chlorine involved both UV photolysis and radical species oxidation, which accounted for 48.4% and 51.6%, respectively. Chlorine dosage and pH are essential parameters affecting the treatment efficiency of UV/chlorine. The pseudo first order rate constant (kobs, DDBAC) increased from 0.046 min−1 to 0.123 min−1 in response to chlorine dosage at 0–150 mg/L, and the degradation percentage of DDBAC within 12 min decreased from 81.4% to 56.6% at pH 3.6–9.5. Five main intermediates were identified and semi-quantified using HPLC-MS/MS and a possible degradation pathway was proposed. The degradation mechanisms of DDBAC by UV/chlorine included cleavage of the benzyl-nitrogen bond and hydrogen abstraction of the alkyl chain. Trichloromethane (TCM), chloral hydrate (CH), trichloropropanone (TCP), dichloropropanone (DCP) and dichloroacetonitrile (DCAN) were detected using GC-ECD. The formation of chlorinated products increased rapidly initially, then decreased (TCM, TCP, DCP and DCAN) or remained stable (CH) with extended treatment. The actual formation of TCM peaked at 30 min (50.3 μg/L), while other chlorinated products did not exceed 10 μg/L throughout the process. Based on the luminescent bacterial assay, DDBAC solution underwent almost complete detoxification subjected to UV/chlorine treatment for 120 min, which is more effective than UV irradiation or chlorination alone.
•UV/chlorine showed synergistic degradation of DDBAC than UV and chlorination.•DDBAC degraded through both UV photolysis and radicals oxidation during UV/chlorine.•Degradation pathway of DDBAC during UV/chlorine oxidation was proposed.•Formation of chlorinated products decreased with extended UV/chlorine oxidation.•UV/chlorine oxidation was efficient at DDBAC detoxification.
As the main component of syngas, reducing CO2 to CO with high selectivity through photocatalysis could provide a sustainable way to alleviate energy shortage issues. Developing a photocatalytic ...system with low cost and high performance that is environmentally friendly is the ultimate goal towards CO2 photoreduction. Herein, an efficient and economic three‐component heterojunction photocatalyst is designed and fabricated for converting CO2 to CO in the absence of organic sacrificial agents. The heterojunction is made of Cu2−xS nanotubes coated with a carbon layer (C‐Cu2−xS) and g‐C3N4. By using the classical MOF material HKUST‐1 as a precursor, hollow tubular‐like metal sulfides (C‐Cu2−xS) with carbon coating were synthesized and further loaded on g‐C3N4, forming a three‐component heterojunction C‐Cu2−xS@g‐C3N4. The carbon coat in C‐Cu2−xS@g‐C3N4 acts as an electron reservoir, which facilitates electron–hole pair separation. The optimized C‐Cu2−xS@g‐C3N4 acted as a photocatalyst in CO2 reduction with a high reactivity of 1062.6 μmol g−1 and selectivity of 97 %. Compared with bare g‐C3N4 (158.4 μmol g−1) and C‐Cu2−xS, the reactivity is nearly 7 and 23‐fold enhanced and this CO generation rate is higher than most of the reported Cu2S or g‐C3N4 composites under similar conditions. The prominent activity may result from enhanced light adsorption and effective charge separation. This work might open up an alternative method for the design and fabrication of high‐performance and low‐cost photocatalysts for efficiently and durably converting CO2 to CO with high selectivity.
CO2 photoreduction: An efficient and economic three‐component heterojunction photocatalyst is designed and fabricated for converting CO2 to CO in the absence of organic sacrificial agents. The heterojunction is made of Cu2−xS nanotubes coated with a carbon layer (C‐Cu2−xS) and loaded onto g‐C3N4.
Anthocyanins, which have important biological functions and have a beneficial effect on human health, notably account for pigmentation in purple-fleshed sweet potato tuberous roots. Individual ...regulatory factors of anthocyanin biosynthesis have been identified; however, the regulatory network of anthocyanin biosynthesis in purple-fleshed sweet potato is unclear.
We functionally determined that IbMYB340 cotransformed with IbbHLH2 in tobacco and strawberry receptacles induced anthocyanin accumulation, and the addition of IbNAC56a or IbNAC56b caused increased pigmentation. Furthermore, we confirmed the interaction of IbMYB340 with IbbHLH2 and IbNAC56a or IbNAC56b via yeast two-hybrid and firefly luciferase complementation assays; these proteins could form a MYB340-bHLH2-NAC56a or MYB340-bHLH2-NAC56b transcriptional complex to regulate anthocyanin biosynthesis by binding to the IbANS promoter rather than the IbUFGT promoter. Furthermore, it was found by a transient expression system in tobacco leaves that IbMYB44 could decrease anthocyanin accumulation. Moreover, the interaction of IbMYB44 with IbMYB340 and IbNAC56a or IbNAC56b was verified. This result suggested that IbMYB44 acts as a repressor of anthocyanin in sweet potato.
The repressor IbMYB44 affected anthocyanin biosynthesis by competitively inhibiting the IbMYB340-IbbHLH2-IbNAC56a or IbMYB340-IbbHLH2-IbNAC56b regulatory complex formation. Overall, the present study proposed a novel regulatory network whereby several vital TFs play key roles in regulating anthocyanin biosynthesis, and it provides strong insight into the potential mechanism underlying anthocyanin biosynthesis in sweet potato tuberous roots with purple color.
Membrane fouling is an important shortcoming limiting the efficiency and wide application of reverse osmosis (RO) technology. In this paper, RO membranes in a full-scale municipal wastewater ...reclamation plant were autopsied. From the lead to tail position RO membranes in RO system, both of organic and inorganic matters on membranes reduced gradually. The higher ion products in RO concentrate didn't result in more serious inorganic scaling on the last position RO membranes, which was contrast with some other researches. Fe, Ca and Mg were major inorganic elements. Fe had a relatively low concentration in RO influent but the highest content on membranes. However, there was no specific pretreatment in terms of Fe removal. Ca and Mg scaling was controlled by the antiscalants injected. Organic fouling (75.0–84.5% of dry weights) was major problem on RO membranes due to the large amount of dissolved organic matters in secondary effluent as raw water. Hydrophilic acid (HIA, 48.0% of total DOC), hydrophobic acid (HOA, 23.6%) and hydrophobic neutral (HON, 19.0%) fraction was largest among the six fractions in RO influent, while HON (38.2–51.1%) and HOA (22.1–26.1%) tended to accumulate on membranes in higher quantities. Monitoring HON and HOA might help to forecast organic fouling.
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•Organic and inorganic fouling reduced from the lead to the tail position RO membranes.•Fe had a low concentration in RO influent but the highest content on RO membranes.•Organic fouling (75.0–84.5% of dry weights) was major problem on RO membranes.•Hydrophilic acid fraction was largest in influent but deposited less on RO membranes.•Hydrophobic neutral and hydrophobic acid tend to deposit excessively on RO membranes.
Gut microbiome is integral to the pathogenesis of ulcerative colitis. A novel probiotic Lactobacillus intestinalis (L. intestinalis) exerts a protective effect against dextran sodium sulfate‐induced ...colitis in mice. Based on flow cytometry, colitis‐associated Th17 cells are the target of L. intestinalis, which is supported by the lack of protective effects of L. intestinalis in T cell‐null Rag1−/− mice or upon anti‐IL‐17‐A antibody‐treated mice. Although L. intestinalis exerts no direct effect on T cell differentiation, it decreases C/EBPA‐driven gut epithelial SAA1 and SAA2 production, which in turn impairs Th17 cell differentiation. Cometabolism of L. intestinalis ALDH and host ALDH1A2 contributed to elevated biosynthesis of retinoic acid (RA), which accounts for the anti‐colitis effect in RAR‐α ‐mediated way. In a cohort of ulcerative colitis patients, it is observed that fecal abundance of L. intestinalis is negatively associated with the C/EBPA‐SAA1/2‐Th17 axis. Finally, L. intestinalis has a synergistic effect with mesalazine in alleviating murine colitis. In conclusion, L. intestinalis and associated metabolites, RA, have potential therapeutic effects for suppressing colonic inflammation by modulating the crosstalk between intestinal epithelia and immunity.
By improving retinoic acid synthesis, a novel probiotic L. intestinalis exerts a protective effect against colitis. Retinoic acid triggers epithelial gene alteration, including SAA1, SAA2, and C/EBPA, to downregulate RORγt+ Th17 cells. L. intestinalis and its associated metabolite, retinoic acid, have potential therapeutic effects for suppressing colonic inflammation.
Objective
To explore the experiences of front‐line nurses combating the coronavirus disease‐2019 epidemic.
Design and Sample
Fifteen front‐line nurses caring for COVID‐19 patients were recruited from ...two hospitals in Wuhan, China from January 26 to February 5, 2020. Data were collected through semi‐structured individual interviews and analyzed using standard qualitative methods.
Results
Four theme categories emerged from the data analysis: (a) “Facing tremendous new challenges and danger”; (b) “Strong pressure because of fear of infection, exhaustion by heavy workloads and stress of nursing seriously ill COVID‐19 patients”; (c) “Strong sense of duty and identity as a healthcare provider”; (d) “Rational understanding of the epidemic—the nurses believed that the epidemic would soon be overcome and would like to receive disaster rescue training.”
Conclusions
Although the intensive rescue work drained front‐line nurses, both physically and emotionally, they showed a spirit of dedication and felt a responsibility to overcome this epidemic. Their experiences provide useful insights into implementing a safer public health emergency rescue system in preparation for future outbreaks of infectious diseases. Specifically, psychological support and humanistic care should be provided to front‐line nurses to maintain their well‐being, and nationwide emergency rescue training and disaster education should be implemented.
UV based advanced oxidation processes (UV-AOPs) that efficiently eliminate organic pollutants during water treatment have been the subject of numerous investigations. Most organic pollutants are not ...completely mineralized during UV-AOPs but are partially oxidized into transformation products (TPs), thereby adding complexity to the treated water and posing risks to humans, ecological systems, and the environment. While the degradation kinetics and mechanisms of pollutants have been widely documented, there is little information about the risks associated with TPs. In this review, we have collated recent knowledge about the harmful TPs that are generated in UV/H2O2 and UV photocatalysis, two UV-AOPs that have been studied extensively. Toxic and assimilable TPs were ubiquitously observed in more than 80% of UV-AOPs of organic pollutants, of which the toxicity and assimilability levels changed with variations in the reaction conditions, such as the UV fluence and oxidant dosage. Previous studies and modeling assessments showed that toxic and assimilable TPs may be generated during hydroxylation, dealkylation, decarboxylation, and deamination. Among various reactions, TPs generated from dealkylation and decarboxylation were generally less and more toxic than the parent pollutants, respectively; TPs generated from decarboxylation and deamination were generally less and more assimilable than the parent pollutants, respectively. There is also potential concern about the sensory-unpleasant TPs generated by oxidations and subsequent metabolism of microorganisms. In this overview, we stress the need to include both the concentrations of organic pollutants and the evaluations of the risks from TPs for the quality assessments of the water treated by UV-AOPs.
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•The risk posed by toxic, assimilable, and sensory-unpleasant TPs is pronounced.•The quantitative levels of the toxicity and assimilability of TPs are surveyed.•Reactions generating toxic and assimilable TPs are surveyed and models assessed.•The influencing factors on the generation of TPs suggests optimizations are need.•Sensory-unpleasant TPs are potential concerns in UV photochemical oxidation.
Inflammasome involvement in Parkinson's disease (PD) has been intensively investigated. Absent in melanoma 2 (AIM2) is an essential inflammasome protein known to contribute to the development of ...several neurological diseases. However, a specific role for AIM2 in PD has not been reported. In this study, we investigated the effect of AIM2 in the N‐methyl‐4‐phenyl‐1, 2, 3, 6‐tetrahydropyridine (MPTP)‐induced PD model by use of various knockout and bone marrow chimeric mice. The mechanism of action for AIM2 in PD was assessed by RNA‐sequencing and in vitro primary microglial transfection. Results were validated in the A30P transgenic mouse model of PD. In the MPTP mouse model, AIM2 activation was found to negatively regulate neuro‐inflammation independent of the inflammasome. Microglial AIM2 deficiency exacerbated behavioral and pathological features of both MPTP‐induced and transgenic PD mouse models. Mechanistically, AIM2 reduced cyclic GMP–AMP synthase (cGAS)‐mediated antiviral‐related inflammation by inhibition of AKT‐interferon regulatory factor 3 (IRF3) phosphorylation. These results demonstrate microglial AIM2 to inhibit the antiviral‐related neuro‐inflammation associated with PD and provide for a foundation upon which to identify new therapeutic targets for treatment of the disease.
Main Points
AIM2 plays an important role in mouse models of Parkinson's disease, independent of the inflammasome.
Microglial AIM2 inhibits Parkinson's disease neuro‐inflammation and pathology.
AIM2 inhibits AKT‐IRF3 phosphorylation, thereby alleviating cGAS‐mediated antiviral inflammation.
Purpose
The aim of this study was to determine a better criterion for end-of-treatment PET (EoT-PET) assessment and prognostic evaluation of patients with diffuse large B cell lymphoma (DLBCL).
...Method
EoT-PET scans were assessed using the visual Deauville 5-point scale (5PS) and LLR, the maximum standard uptake value ratio between the lesion and the liver. The cutoff value of LLR was obtained by receiver operator characteristic curve analysis. Patient outcomes were compared using Kaplan–Meier survival analysis. Prognostic indexes of different criteria were compared. Multivariate Cox regression analysis was performed to evaluate the prognostic factors.
Results
Four hundred forty-nine newly diagnosed DLBCL patients who received rituximab-based immunochemotherapy were included, and the median follow-up duration was 41.4 months. Patients with Deauville score (DS) 4 displayed significantly longer PFS and OS compared with patients with DS 5 (both
p
< 0.001), and they had significantly shorter PFS (
p
< 0.01) but similar OS (
p
= 0.057) compared with patients with DS 1–3. The differences in PFS and OS between groups were all significant whether positive EoT-PET was defined as DS 4–5 or DS 5 (all
p
< 0.001). The optimal cutoff of LLR was 1.83, and both PFS and OS were significantly different between EoT-PET-positive and EoT-PET-negative patients as defined by the cutoff (both
p
< 0.001). LLR-based criterion displayed higher specificity, positive predictive value, and accuracy than 5PS-based criterion in the prediction of disease progression and death events. In the multivariate analysis, positive EoT-PET (as defined by LLR) was related to unfavorable PFS and OS (both
p
< 0.001). Additional treatment was not correlated with outcomes of EoT-PET-negative patients either defined by LLR or 5PS or EoT-PET-positive patients classified by 5PS, but it was the only beneficial factor for OS (
p
< 0.05) in EoT-PET-positive patients with LLR ≥ 1.83.
Conclusion
The optimal cutoff of LLR may be superior to Deauville criteria in identifying low-risk DLBCL patients with negative EoT-PET after the first-line immunochemotherapy and sparing them the cost and toxicity of additional treatment.
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