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Background: Similar to hypochlorous acid (HClO), hypobromous acid (HBrO) is one of the most notable reactive oxygen species (ROS). Overexpression of HBrO is linked to various diseases causing organ and tissue loss. Due to HBrO's role in the oxidation of micropollutants, real-time monitoring of HBrO in water-based systems is essential. Tetraphenylethylene (TPE)-based organic aggregation-induced emission luminophores (AIEgens) are an emerging category of fluorescent probe materials that have attracted considerable attentions. However, AIE probes are rarely applied to detect HBrO. Developing faster, more precise, and more sensitive AIE probes is thus crucial for detecting biological and environmental HBrO., Results: A small molecule fluorescent probe 4-(1,2,2-triphenylvinyl)benzamidoxime (SWJT-21) was synthesized for the sensitive and selective detection of hypobromous acid (HBrO) based on aggregation-induced emission (AIE). The amidoxime unit of SWJT-21 would undergo an oxidation reaction with HBrO, leading to a structure differentiation between the probe and the product, and therefore the turn-on fluorescence by the AIE effect. The probe could recognize hypobromous acid rapidly (less than 3 s) in high aqueous phase (99 % water) with a turn-on fluorescence response. It was determined that the limit of detection for HBrO was 5.47 nM. Moreover, SWJT-21 demonstrates potential as a test strip for the detection of HBrO. SWJT-21 was also successfully used for the monitoring of HBrO in water samples and for the detection of endogenous/exogenous HBrO in living cells and zebrafish., Significance: A special AIE fluorescence turn-on probe SWJT-21 based on tetraphenylethylene was designed for detecting HBrO in the environmental and biological systems. This probe has an extremely low detection limit of 5.47 nM and is able to detect HBrO in 99 % aqueous phase in less than 3 s., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Kinds of antibiotics are used to prevent and control bacteria infections, unfortunately, the overuse and misuse of antibiotic have promoted the emergence and spread of antibiotic-resistant bacteria. Therefore, understanding the mechanism of antibiotic resistance is very important. This study explores the combined effection of metal ions and antibiotic to the drug resistance of Escherichia coli. Our results found that the minimum inhibitory concentration (MIC) increased as the ammonium ferric citrate concentration increased, especially for gentamicin antibiotic. When the Fe 3+ concentration reached 300 μM, the survival of E. coli was stably restored with the increased gentamicin concentration. Exogenous Fe 3+ could decrease intracellular gentamicin concentration. On the other hand, Fe 3+ treatment together with gentamicin could reduce reactive oxygen species (ROS) production, characterized by decreased levels of NADH and ATP. Furthermore, ROS-scavenging enzymes of superoxide dismutase (SOD) and catalase (CAT) were up-regulated and H 2 O 2 plus gentamicin-mediated killing was restored by Fe 3+ . These results may have significant implications in understanding bacterial antibiotic-resistant mechanisms based on the external Fe 3+ concentration., Competing Interests: Declaration of competing interest The authors declare there is no conflict of interest., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Photodynamic therapy (PDT) received great attention in cancer therapy due to the advantages of negligible drug resistance, low side effects, and minimal invasiveness. Development of theranostic nanoprobes with specific imaging-guided PDT is of great significance in the field. Herein we report the fabrication of a novel theranostic nanoprobe porphyrin/G-quadruplex conjugated gold/persistent luminescence nanocomposites for imaging-guided PDT. The developed nanoprobe contains NIR-emitting persistent luminescent nanoparticles (PLNP) as the core for autofluorescence-free bioimaging and Au coating on PLNP for facile subsequent DNA conjugation. The DNA sequence is designed to contain G-rich AS1411 aptamer for recognizing the over-expressed cellular nucleolin of cancer cell and forming a G-quadruplex structure to combine with tetrakis (4-carboxyphenyl) porphyrin (TCPP) to realize PDT. The AS1411 aptamer-contained DNA conjugated Au-coated PLNP is rapidly prepared via a freezing method with high content of DNA and good aqueous stability. Meanwhile, TCPP is easily loaded into the G-quadruplex structure formed from G-rich AS1411 aptamer on the surface of Au/PLNP in presence of K + . The theranostic nanoprobe gives integrated merits of PLNP for autofluorescence-free bioimging, TCPP for PDT and AS1411 aptamer-contained DNA for specific binding to cancer cells. This work provides a new specially designed imaging-guided PDT nanoplatform for theranostics., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Antibiotic-resistant bacteria are an increasingly serious threat to human health and aquaculture. To further explore bacterial antibiotic resistance mechanism, iTRAQ is used to identify a differential proteome in ampicillin-resistant LTB4 (LTB4-R AMP ), a strain of Edwardsiella piscicida. A total of 102 differentially proteins with 50 upregulation and 52 downregulation are identified. Since many of these changes are related to metabolism, interactive pathways explorer(iPath) is used to understand a global differentially metabolic response in LTB4-R AMP. This analysis identifies a global depressed metabolic modulation as the most characteristic feature of LTB4-R AMP . Lower membrane potential and ATP in LTB4-R AMP than control support that the central carbon metabolism and energy metabolism are reduced. Since the pyruvate cycle (the P cycle) plays a key role in the central carbon metabolism and energy metabolism, further investigation focuses on the P cycle and shows that expression of genes and activity of enzymes in the P cycle are decreased in LTB4-R AMP . These results support the conclusion that the depressed P cycle contributes to the acquisition of ampicillin resistance in E.piscicida. These findings indicate that the combination of proteomics and iPath analysis can provide a global metabolic profile, which helps us better understand the correlation between ampicillin resistance and cellular metabolism. SIGNIFICANCE: The present study uses iTRAQ to explore ampicillin resistance mechanism in Edwardsiella piscicida and finds many of these differential abundances of proteins are related to metabolism. IPath further identifies a global depressed metabolic modulation and characterizes the reduced pyruvate cycle as the most characteristic feature of the ampicillin-resistant E. piscicida, which is supported by reduced expression of genes and activity of enzymes in the pyruvate cycle. Consisitently, lower membrane potential and ATP are detetced. These results reveal the metabolic mechanism of ampicillin resistance and provide a solid proof to revert the resistance by reprogramming metabolomics., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Investigations into the photosynthetic response of urban trees on paved land under drought stress would help to improve the management of trees under rapid urbanization and climate change. An experiment was designed to grow two common greening tree saplings, ash (Fraxinus chinensis Roxb.) and ginkgo (Ginkgo biloba L.), in environments of both land pavement and drought. The results showed that (1) land pavement increased surface and air temperatures and decreased air humidity as well as net photosynthetic rate (P n ) and photosynthetic capacity (A max ) of ginkgo significantly; (2) drought significantly decreased P n , A max and maximum net photosynthetic rate (P nmax ) as well as other photosynthetic parameters of both ash and ginkgo; (3) the negative effects of the combination of land pavement and drought on photosynthetic parameters were more significant than the effects of drought treatment for both ash and ginkgo. This implies that urban trees, especially those growing on land pavements, will confront harsher environments and a greater decline of photosynthesis under the severe and more frequent droughts predicted in the future. Overall, ash showed more tolerance to land pavement and drought than ginkgo, indicating that the selection of tolerant tree species is important for urban planting., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We previously showed that glucose potentiated kanamycin to kill multidrug-resistant Edwardsiella piscicida through activation of the TCA cycle. However, whether other regulatory mechanism is involved requires further investigation. By quantitative proteomics technology, iTRAQ, we systematically mapped the altered proteins in the presence of glucose and identified 94 differentially expressed proteins. The analysis of the altered proteins by pathways, amino acid biosynthesis and metabolism were enriched. And the most significantly altered eight amino acids tyrosine, phenylalanine, valine, leucine, isoleucine, glycine, serine and threonine were investigated for their potentiation of kanamycin to kill EIB202, where glycine, serine and threonine showed the strongest efficacy than the others. The combinations of glycine and serine or glucose with glycine, serine or threonine had the best effects. Moreover, pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and succinate dehydrogenase activities were increased as well as the proton motive force (PMF) and intracellular kanamycin. Finally, inhibitors that disrupt PMF production abolished the potentiation. These results shed light on the mechanism of how glucose promoting the amino acids biosynthesis and metabolism to potentiate kanamycin to kill antibiotic-resistant bacteria. More importantly, our results suggested that adjusting amino acid biosynthesis and metabolism might be a strategy to become phenotypic resistance to antibiotics in bacteria., Significance: Tackling antibiotic resistance is an emerging issue in current years. Despite the efforts made toward developing new antibiotics, the progress is still lagged behind expectation. Novel strategies are required. The use of metabolite to revert antibiotic resistant is highly appreciated in recent years due to the less toxicity, more economic and high efficacy. As a continued study of our previous report on glucose potentiating kanamycin to kill antibiotic-resistant bacteria. The current study further expands the previous discovery on the mechanism of how glucose potentiate this effect. This result provides more basis on the action of glucose in reverting antibiotic resistance. And more importantly, we may derive more metabolites other than glucose to manage antibiotic resistance., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Antibiotic-resistant Edwardsiella tarda poses a severe challenge to aquaculture. An understanding for antibiotic-resistant mechanisms is crucial to control the disease. The present study characterizes E. tarda ampicillin-stressed proteome and shows the importance of energy metabolism including the TCA cycle and glycolysis/gluconeogenesis in the antibiotic resistance. Further combination with antibiotic measurement develops a new method for identification of antibiotic-binding proteins out of differential abundances of proteins and results in determination of ETAE_0175 and ETAE_3367 as ampicillin-binding proteins in E. tarda. Genes of the two proteins are cloned and recombinant proteins are purified for validation of antibiotic-binding capability. Results show that higher binding capability is detected in ETAE_3367 than ETAE_0175. Out of the two proteins, ETAE_3367 is first reported here to be an antibiotic-binding protein, while ETAE_0175 homology in other bacteria has been shown to bind with other antibiotics. Bioinformatics analysis shows that ETAE_3367 may closely interact with aceF and sucA belonging to the TCA cycle and glycolysis/gluconeogenesis, respectively. These results indicate that energy metabolism contributes to ampicillin resistance in E. tarda and a new method to identify antibiotic-binding proteins is developed. These findings highlight the way to an understanding of antibiotic-resistant mechanisms in content of antibiotic-binding proteins., Biological Significance: Our data characterizes Edwardsiella tarda ampicillin-stressed proteome and shows the importance of energy metabolism including the TCA cycle and glycolysis/gluconeogenesis in the antibiotic resistance. Furthermore, a new method based 2-DE proteomics is developed for identification of antibiotic-binding proteins, which results in determination of ETAE_0175 and ETAE_3367 as ampicillin-binding proteins in E. tarda. ETAE_3367 is closely interacted with proteins of the TCA cycle and glycolysis/gluconeogenesis, suggesting the drug-resistant mechanism., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A new D:B-friedoolean-type triterpene, 3β-acetoxyglutin-5(10)-en-6-oxo (1), together with seventeen known compounds (2-18) was isolated from the roots of Scorzonera austriaca. Their structures were elucidated mainly by NMR and HR-ESI-MS, as well as on comparison with the reported data. Cytotoxicities of compounds 2, 4, 6, 10-14 and 16 against selected cancer cells of human promyelocytic leukemia (HL-60) and human hepatoma (BEL-7404) were measured in vitro., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Silver was reclaimed from silver-plating wastewater by using a pulsed electric field (PEF) combined with static cylinder electrodes (SCE). The conditions that produced the maximal silver recovery rate (RR(Ag)) (99%) were as follows: average retention time of 10 min, interelectrode gap of 50mm, solution pH of 9.0, temperature of 45 degrees C, initial Ag(I) concentration of 1000 mg L(-1), PEF pulse frequency of 1200 Hz, current density of 5.0 A m(-2) and a pulse duty cycle of 60%. Compared with the conventional direct current (DC) technology, the PEF process exhibited improvements in the silver recovery rate (RR(Ag)), total energy consumption (TEC) and physical properties of the silver deposits, especially for low Ag(I) concentrations, for example, from 500 to 1000 mg L(-1). For an initial Ag(I) concentration of 500 mg L(-1), the PEF process produced an RR(Ag) of up to 99%, and the TEC was 4.56 kWh (kg Ag)(-1). In comparison, the RR(Ag) and TEC were 90% and 5.66 kWh (kg Ag)(-1), respectively, in the DC process. The results of SEM observation and XRD analysis indicated that the silver deposits formed by the PEF process were smaller, denser, and of a higher purity than those produced by the DC process. Therefore, the presented method was effective for reclaiming silver from silver-plating wastewater.