Frontiers in Pharmacology
·
2019
·
IF 3.845
Lin Xiao-mian,Luo Wu,Wang Heng,Li Rong-zhen,Huang Yi-shan,Chen Lian-kuai,Wu Xiao-ping
The prostaglandin-endoperoxide synthase-2 (PTGS2) plays essential roles in diverse pathological process. Although recent studies implied that PTGS2 was closely related with chemoresistance, the precise roles and the underlying mechanisms of PTGS2 in the developing process of chemoresistance in non-small cell lung cancer (NSCLC) remained elusive. In the present study, we revealed a novel molecular mechanism of PTGS2 implicated in the chemoresistance of NSCLC and proposed a model for the positive feedback regulation of PTGS2 in the process of developing resistance phenotype in NSCLC cells. Our results demonstrated that cisplatin induced PTGS2 expression through the ROS-ERK1/2-NF-κB signaling axis. The prostaglandin E2 (PGE2) derived from PTGS2 catalyzation further strengthened PTGS2 expression via the PGE2-EPs-ERK1/2 positive feedback loop, which induced multidrug resistance of NSCLC cells through up-regulation of BCL2 expression and the subsequent attenuation of cell apoptosis. Consistently, high levels of both PTGS2 and BCL2 were closely associated with poor survival in NSCLC patients. Inhibition of PTGS2 significantly reversed the chemoresistance in the resistant NSCLC in vitro and in vivo. Our results suggested that PTGS2 might be employed as an adjunctive therapeutic target for improving the response to the therapeutic agents in a subset of resistant NSCLC.
研究领域:
肿瘤学
·
分子生物学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Jialing Tian,Yi Han,Pengna Yin,Jianbing Zhang,Tingting Guo,Haibo Li,Yanan Hou,Yuanyuan Song,Jianbo Guo
Under high-strength perchlorate concentration ranging from 300 to 1300 mg/L, the dissimilatory perchlorate reducing granular sludge (DPR-GS) was successfully cultivated in an up-flow anaerobic sludge blanket (UASB) reactor to investigate performance and starvation recovery for treating perchlorate wastewater. The mature DPR-GS had excellent perchlorate removal efficiency (98.47%) at 1200 mg/L. Microbial community analysis suggested that the dominant genera in mature DPR-GS were Sulfurospirillum and Acinetobacter . The DPR-GS system conformed well to the modified Stover-Kincannon model with the maximum substrate utilization (U max ) of 90.01 kg/(m 3 ·d) and the saturation value constant (K B ) of 83.93 kg/(m 3 ·d). Additionally, the starvation recovery of DPR-GS system was first investigated. The perchlorate removal efficiency recovered to 91.39% after 8 days under the 30-day starvation stress, and the microbial activity also recovered to normal condition. The three-dimensional excitation-emission matrix (3D-EEM) proved that the tryptophan-like component in extracellular polymeric substance (EPS) increased during the starvation period, which was associated with immune functions and played an important role in maintaining the microbial activity. Meanwhile, the secretion of humic acid-like component in EPS promoted electron transfer efficiency, thus improving microbial metabolic activity during the recovery period. Further analysis by the parallel factor (PARAFAC) of 3D-EEM confirmed that the decrease of immune substances and the increase of metabolic products in EPS during the starvation recovery period, which enhanced the recovery of microbial activity and the improvement of perchlorate removal performance. This study revealed the response of the DPR-GS system to high-strength perchlorate and starvation stress, thus provided a further basis of perchlorate tolerance and starvation recovery for the application of DPR-GS system to remove high-strength concentrated perchlorate from contaminated water .
研究领域:
环境工程
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微生物学
·
水处理技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
·
2022
·
IF 4.907
Yimin Xie,Xiaoyuan Guo,Zhiwei Liang,Hojae Shim
Di-2-ethylhexyl phthalate (DEHP) widely exists in the environment and has raised an increasing global concern. A bacterial strain capable of degrading DEHP was isolated from the activated sludge at a local wastewater treatment plant and identified as Bacillus sp. MY156. A nearly complete degradation of DEHP at 500 mg L −1 was reached within 5 days when MY156 was grown at pH 8 and 30 °C. The biodegradation of DEHP (50–600 mg L −1 ) followed the first-order kinetics. Mass balance analysis showed the efficient degradation of DEHP with the ratio of biomass to DEHP at 0.72. The dehydrogenase activity was positively related to the biodegradation of DEHP, while the extracellular polymeric substance (EPS) might have played a key role in overcoming the potential inhibition caused by DEHP. The microelements (Fe 3+ , Zn 2+ , and Mn 2+ ) supplements stimulated the DEHP degradation while copper (Cu 2+ ) showed inhibitory. The proposed intermediate metabolites of the DEHP degradation included mono-ethylhexyl phthalate, diethyl phthalate, dimethyl phthalate, phthalic acid, and protocatechuate. Together with the micro-morphological observation, biodegradation experiments in saline and different real water environments suggested the isolate possessing strong halo-tolerance and potential applicable ability to adapt to various environmental conditions. The isolate could be used as a potential and efficient phthalic acid esters (PAEs) degrader for the bioremediation of contaminated sites.
研究领域:
环境微生物学
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生物技术
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污水处理
·
降解与代谢
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 25
·17547-17556
·
IF 3.9
Shilei Tang,Shaobin Huang,Pengfei Chen,Zhipeng Wu,Tianyu Zhao
Dredged sediment poses significant challenges for transportation and subsequent treatment due to its high water content and large volume. Coagulation, a common method of dewatering, can significantly enhance the dewatering performance of dredged sediment. This study synthesized a cationic starch-based flocculant [starch-3-chloro-2-hydroxypropyl trimethylammonium chloride (St-CTA)] through etherification for the flocculation dewatering of dredged sediment. The effectiveness and mechanism of St-CTA as a dewatering flocculant for dredged sediment were investigated. The results demonstrated that when the dosage of St-CTA was 12 mg g−1 TSS (total suspended solids), the dehydration property of dredged sediment substantially improved, with the specific resistance to filtration (SRF) decreasing by 93.3%, the capillary suction time (CST) by 93.5%, and the water content of the filter cake (WC) by 9.7%. The removal rate of turbidity of the supernatant from the conditioned dredged sediment reached 99.6%, accelerating the settling speed and effectively capturing and separating fine particles from the sediment. St-CTA significantly increased the median particle size (D50), altered the microstructure and extracellular polymeric substances (EPS) of the flocs, and increased the fractal dimension of the flocs, making them more compact and conducive to the formation of drainage channels. These findings confirm the feasibility of using potentially environmentally friendly St-CTA as a rapid dewatering conditioning agent for sediment.
研究领域:
环境工程
·
水处理
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Zi Song,Runfeng Liao,Mingming Wang,Jianjun Zhang,Zijun Dong,Zheng Wen,Wenyi Dong,Feiyun Sun
Biofilm formation is a complex and time-consuming process, especially the attachment and growth of anaerobic biofilm, which fundamentally determines the start-up of biofilm reactor . In this study, biosurfactant, rhamnolipid, was introduced into an anaerobic moving bed biofilm reactor (AnMBBR) to promote its start-up, and the results showed that AnMBBR with rhamnolipid (RMBBR) could be successfully started within 25 days. Compared to the control AnMBBR without rhamnolipid, the start-up time was shortened by about half, the attached biomass on biocarriers was increased to 1.5 times, and the pollutants removal efficiencies were all greatly improved in the start-up phase, especially NO 3 − increased from 86.76 ± 1.04% to 96.93 ± 0.73%, and then these gaps were reduced in the steady-state phase. Under the action of rhamnolipid, the adhesion force of the biofilm increased from 18.9 nN to 27.4 nN eventually, and the interfacial energy between biofilm and biocarriers was transformed from repulsion (6200 KT) to weak attraction (−100 KT) by the evaluation of the extended Derjaguin–Landau–Verwey–Overbeek theory, which significantly promoted the initial attachment of biofilm. The increased metabolic activity , key enzyme activity, extracellular polymeric substances (EPS) and quorum sensing behaviors evidenced that rhamnolipid stimulated microbial internal activities and then regulated biofilm growth process. Moreover, rhamnolipid also significantly enhanced the abundance of functional bacteria in terms of metabolism or quorum sensing, including Thauera , Methylomonas , Desulfomicrobium , Azoarcus , Leptonema . Rhamnolipid would also stimulate the expression of genes that related to membrane transport, biofilm formation and nitrogen metabolism . This work provided a promising strategy for the rapid start-up of anaerobic biofilm reactor.
研究领域:
环境工程
·
微生物学
·
生物技术
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2020
·
IF 9.13
Kun Li,Jin Qian,Peifang Wang,Chao Wang,Bianhe Lu,Wen Jin,Xixian He,Sijing Tang,Chao Zhang,Pan Gao
Most of the current studies on the toxicology of pristine nanoparticles (NPs) are environmentally irrelevant, because their ‘‘aging’’ process accompanied by the physicochemical transformation is inevitable in the environment. Considering aging phenomenon will gain a better understanding of the toxicity and fate of NPs in the environment. Here, we focused on the physicochemical transformation of anatase-NPs (TiO 2 -A) and rutile-NPs (TiO 2 -R) after 90 days of aging and investigated the responses of freshwater biofilm formation to the stress changes of naturally aged TiO 2 -NPs (aTiO 2 -NPs). We found that after aging, the TiO 2 -NPs underwent sophisticated physicochemical transformations in the original morphology and microstructure owing to organic and crystal salts inclusions, such as energy band changes and the formation of Ti 3+ on the NPs surfaces. These comprehensive transformations increased the stability of NPs in the exposed suspension. However, the physicochemical transformations were crystal-forms-dependent, and aging did not change the crystal structure and crystallinity . Interestingly, compared to pristine NPs, aTiO 2 -NPs showed much lower cytotoxicity and had the weaker ability to promote or inhibit the biofilm formation (p < 0.05) owing to the passivation of photoactivity caused by the comprehensive effect of the inclusions, especially for aTiO 2 -A. Regardless of aging or not of crystal forms, responses of biofilm formation were exposure-concentration-dependent, namely low concentration promotion (0.1 mg/L) and high concentration inhibition (10 mg/L), e.g., role transition of the pioneers (algae or bacteria) in initial colonization, extracellular polymeric substances (EPS) secretion and compositions of development stages with polysaccharide (PS)-rich and protein (PRO)-rich stages, and biomass and cell activity at different depths of mature biofilms. The reactive oxygen species (ROS) induced by TiO 2 -NPs showed typical hormesis. The changing trends of the autoinducers (c-di-GMP and quorum sensing signals including AHL and AI-2) were highly consistent with the growth stages of biofilms and were stimulated or suppressed by TiO 2 -NPs. The NPs crystal-dependently changed the microorganism community structures, while the UPGMA clustering of bacteria was based on the growth stages of the biofilms. The toxic mechanisms revealed that photoactivity and nanoscale retention of particles are the main reasons for the differences in the ecological stress capacity of four kinds of TiO 2 -NPs. Aging reduced characteristic differences of two pristine NPs and even reversed their relative stresses levels (p > 0.05). However, the toxicity of high-concentration aTiO 2 -NPs (10 mg/L) remained serious in a water environment. This study provides a better understanding for the water environmental risks evaluation and policy control of nanoparticles, that is, the effect of time aging has to be considered.
研究领域:
环境科学
·
纳米技术
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生态毒理学
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微生物学
·
水生生态学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Kangyong Zhang,Sibo Liu,Hongwei Tang,Smith Etareri Evivie,Zengwang Guo,Bailiang Li
Exopolysaccharides (EPS) yield and added concentration of lactic acid bacteria can greatly affect the processing characteristics of fermented milk. In order to investigate the effects and mechanisms of EPS yield and added concentration on fermented milk, researchers extracted EPS from 50 strains of Lactobacillus helvedicus ( L. helvedicus ) and selected the two strains with the largest difference in EPS yield ( L. helvedicus LH18 and L. helvetigus LH33) for subsequent experiments. The physicochemical properties of EPS-LH18 and EPS-LH33 were analyzed. The gel characteristics and protein conformation of fermented milk were studied by means of texture analyzer, rheometer, scanning electron microscopy, nuclear magnetic resonance machine, fluorescence spectrophotometer and circular dichroism . The results indicate that the monosaccharide compositions of EPS-LH18 and EPS-LH33 are the same and have good thermal stability . The texture and rheological properties of L. helveticus LH18 fermented milk are significantly superior to other fermented milk. The reason is that L. helveticus LH18 EPS has the highest yield, which leads to a denser gel structure, lower surface hydrophobicity and free sulfhydryl content of its fermented milk. According to circular dichroism analysis, β- sheet and random coil are the internal factors leading to the difference in fermented milk gel. In addition, the fermented milk improved even more favorably as the concentration of the two EPS additions increased. As described above, L. helveticus LH18 has the potential to be an excellent yogurt starter, and both of the above EPS can be used as probiotic stabilizer alternatives for fermented dairy products.
研究领域:
食品科学
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微生物学
·
乳品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2024
·
IF 8
Keyang Jiang,Xiao Yang,Qian Gao,Junxia Ni,Jinhu Feng,Di Wu,Xuelian Zou,Li Hu,Xi Liu,Zhaoping Song,Zhiwei Wang
In this study, exogenous N-acyl-homoserine lactones (AHLs) was added to resist the stress by high concentration (0.5 g/L) of urea formaldehyde resin microplastics (UF-MPs) on anaerobic granular sludge (AnGS), aiming to provide a viable strategy for AnGS to withstand elevated levels of UF-MPs toxicity elucidate the intricate regulatory mechanism of AHL-mediated AnGS-QS regulation. The results showed that the three different signaling molecules (C4-HSL, C6-HSL, and C8-HSL) improved the performance of AnGS under high concentration (0.5 g/L) urea-formaldehyde resin stress, and increased sludge COD removal (4.48%, 4.76%, and 3.35%, respectively) and methanogenic activity (8.38%, 1.92%, and 18.76%, respectively). The addition of C4-HSL has the best effect on sludge particle size and strength, which is attributed to the fact that C4-HSL can significantly increase the content of polysaccharides and proteins in tightly bound extracellular polymeric substances (TB-EPS) (27.1% and 27.1%, respectively). C8-HSL most obviously promotes energy metabolism and EPS biosynthesis gene expression. Metagenomic analysis showed that trace AHLs could promote the abundance of enzymes and functional genes related to the main pathway of methane metabolism, increase the relative abundance of Methanothrix of acetophilic methanogens from 27.79% in the control group to 27.85% (C4-HSL), 28.90% (64-HSL), and 30.03% (C8-HSL), thereby improving community stability.
研究领域:
环境工程
·
微生物学
·
污水处理
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
npj Clean Water
·
2024
·Vol. 7
·期 1
·1-13
·
IF 10.4
Chen Chao,Yang Yu,Choo Kwang-Ho,Ng How Yong,Takizawa Satoshi,Hou Li-an
Membrane biofouling poses an ongoing challenge in seawater reverse osmosis (SWRO) desalination. Here we delved into the impact of seasonal variations in microbial communities on membrane biofouling and innovatively fabricated quorum sensing inhibitors (acylase (AC) and methyl anthranilate (MA))-modified membranes to combat it. Results indicated that Proteobacteria dominated in seawater and membrane biofilm across all seasons, while other phyla varied seasonally. At the class level, the two leading bacteria on the membrane were Gamma- and Alphaproteobacteria , constituting 14–48% and 4–27%, respectively. Genera like Arcobacter , Vibrio , and Rhodobacteraceae were identified as keystone species that exhibited a significant positive correlation with extracellular polymeric substance (EPS) and biofilm formation, leading to a substantive reduction in membrane flux by 70 to 77%. The introduction of AC and MA inhibitors on the membrane suppressed keystone bacteria Rhodobacteraceae and Arcobacter and affected their metabolism, thereby significantly reducing EPS by 65–69% and 55–59%, respectively, and alleviating membrane flux decline by 30–32% and 18–22%, respectively, compared to the pristine membrane. These findings shed new light on the seasonal patterns of membrane biofouling and provide valuable insights into anti-biofouling strategies based on QS inhibition for collaborative biofilm formation.
研究领域:
环境科学
·
微生物学
·
水处理
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD QUALITY
·
2023
·
IF 3.3
Jing-Xin Ye,Yun-Fang Qian,Wei-Qing Lan,Jing Xie
Biofilms composed of microbes and extracellular polymeric substances (EPSs) pose a significant risk to human health and lead to economic loss in the food industry. In this study, the antimicrobial and antibiofilm properties of kojic acid (KA) against Aeromonas sobria (A. sobria) and Staphylococcus saprophyticus (S. saprophyticus) were investigated by determining the leakage of DNA and protein, cell morphology, biofilm formation, the metabolic activity of biofilms, excretion of EPS, and biofilm architecture. The results indicated that the values of minimum inhibitory concentration (MIC) of A. sobria and S. saprophyticus after KA treatment were 0.4 mg/mL and 1.6 mg/mL, respectively. 1 × MIC KA showed unignorable antimicrobial activity against the two bacteria, leading to alterations in the bacterial physicochemical characteristics and cell death. Sub-MICs of KA can inhibit biofilm formation and decrease the metabolic activity and excretion of EPS, and these inhibition effects were in a dose-dependent manner. These results were further confirmed by the visual images obtained from scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Moreover, S. saprophyticus is more susceptible to KA in inhibiting biofilm formation, and for A. sobria, changes in the cell structure and the permeability of the cell membrane were more obvious. This research highlighted the antibacterial and antibiofilm activity of KA against A. sobria and S. saprophyticus.
研究领域:
微生物学
·
生物技术
·
食品科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Xinyue Zhang,Tao Lin,Fuchun Jiang,Xue Zhang,Shiyu Wang,Shisheng Zhang
Pipe material and residual chlorine are key factors for the drinking water distribution system, and understanding the biofilm ecosystem is vital for water quality safeguard. The aim of our study was to determine the influence of pipe materials (ductile iron, steel, polyethylene) and chlorination on the biofilm structure and microbial community , as shown by the physicochemical properties , extracellular polymeric substances (EPS) structural characteristics, bacterial community composition, and functional traits. EPS spatial properties were studied based on a semi-quantitative confocal laser scanning microscope (CLSM) description. Regarding the impact of chlorination, residule chlorine (1.0 ± 0.3 mg L −1 free chlorine) could inhibit the bacteria colonization, and initiate a potential response to external disinfectants revealed by the EPS spatial distribution changes and communities variation compared to unchlorinated system. Regarding the impact of pipe material, polyethylene (PE) biofilms displayed lower biomass, loose zoogloea structure, lower proteins and polysaccharides content, and poor microbial diversity in contrast to ductile iron and steel biofilms. Pipe material was the more possible driving factor of the biofilm community composition compared to the chlorination based on principal coordinates analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA). Actinobacteria was dominant in the PE biofilms (45.57%–83.32%), while Alphaproteobacteria (34.30%–73.22%) and Gammaproteobacteria (6.46%–36.82%) were the major classes in the steel and ductile iron biofilms. The genus Rhodococcus was predominant in the PE biofilms. Rhodococcus , Pseudomonas , and Sphingomonas seemed to have a better growth advantage in the chlorinated system and display a stronger disinfectant resistance. Functional sketch prediction indicated the potential impact of pipe material and chlorination on functional pathway abundnce, possible functional pathways associated with infectious disease included. This study provides insights into the impact of pipe material and chlorination on biofilm structure and microbial community and might help to develop monitoring or maintenance strategies to protect the biosafety of the drinking water.
研究领域:
环境科学
·
微生物学
·
水利工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF DENTISTRY
·
2020
·
IF 3.242
Jinzhao Yu,Xiaoyu Huang,Xuedong Zhou,Qi Han,Wen Zhou,Jingou Liang,Hockin H.K. Xu,Biao Ren,Xian Peng,Michael D. Weir,Mingyun Li,Lei Cheng
Objectives Resin infiltrant is used in early enamel caries. However, commercial resin infiltrant lacks persistent antibacterial activity. Dimethylaminododecyl methacrylate (DMADDM) was added to resin infiltrant to give it sustainable antibacterial properties and inhibit demineralization. Methods After the application of resin infiltrant to bovine enamel, cytotoxicity, surface roughness, and aesthetics were assessed. A multi-species biofilm was incubated on the enamel disk before and one month after microbial-aging. After a 48-h anaerobic incubation, biomass accumulation, metabolic activity, and lactic acid were analyzed using a crystal violet assay, an MTT (3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and a lactic acid assay. Biofilm structure and composition were determined by live/dead staining, exopolysaccharide (EPS) staining, scanning electron microscopy (SEM), and quantitative polymerase chain reaction (qPCR). The depth and content of demineralization were tested by transverse microradiography (TMR). Results Incorporating DMADDM did not increase the cytotoxicity or change the physical properties when the mass fraction of the DMADDM was 2.5–10 %. The modification decreased the amount of bacterial biofilm, metabolic activity, lactic acid production, EPS, and the proportion of Streptococcus mutans in the biofilms. It also provided anti-demineralization effects. The surface roughness and antibacterial ability were not changed after one month of microbial-aging. Conclusion The incorporation of DMADDM improved the antibacterial and anti-demineralization effects of the material. It demonstrated a sustained antibacterial effect. Clinical significance The antibacterial modification might be a potential choice for future clinical applications to inhibit early enamel caries.
研究领域:
牙科材料
·
口腔微生物学
·
龋齿预防
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）