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1.
Cancer Sci ; 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32369664

RESUMO

Gastric cancer (GC) is one of the deadliest cancers worldwide, and the progression of gastric carcinogenesis (GCG) covers multiple complicated pathological stages. Molecular mechanisms of GCG are still unclear. Here, we performed NMR-based metabolomic analysis of aqueous metabolites extracted from gastric tissues in an established rat model of GCG. We showed that the metabolic profiles were clearly distinguished among five histologically classified groups: control (CON), gastritis (GS), low-grade gastric dysplasia (LGD), high-grade gastric dysplasia (HGD) and GC. Furthermore, we conducted metabolic pathway analysis based on identified significant metabolites, and revealed significantly disturbed metabolic pathways closely associated with the four pathological stages, including oxidation stress, choline phosphorylation, amino acid metabolism, Kreb's cycle and glycolysis. Three metabolic pathways were continually disturbed during the progression of GCG, including taurine and hypotaurine metabolism, glutamine and glutamate metabolism, alanine, aspartate and glutamate metabolism. Both the Kreb's cycle and glycine, serine and threonine metabolism were profoundly impaired in both the HGD and GC stages, potentially due to abnormal energy supply for tumor cell proliferation and growth. Furthermore, valine, leucine and isoleucine biosynthesis and glycolysis were significantly disturbed in the GC stage for more energy requirement of the rapid growth of tumor cells. Additionally, we identified potential gastric tissue biomarkers for metabolically discriminating the four pathological stages, which also showed good discriminant capabilities for their serum counterparts. This work sheds light on the molecular mechanisms of gastric carcinogenesis, and is of benefit to the exploration of potential biomarkers for clinically diagnosing and monitoring the progression of GCG.

2.
J Colloid Interface Sci ; 575: 206-219, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32361237

RESUMO

Environment-friendly treatment process relies on the robustness, durability, and performance of catalysts to drive the development of cutting-edge sustainable technologies for the elimination of refractory contaminants. Herein, nanocomposites prepared from zero-valent Co-Fe encapsulated in nitrogen-containing carbon (NC) nanoparticles (CFNC-30 NPs) derived from CoFe2O4@zeolitic imidazolate frameworks-67 were successfully prepared through pyrolysis integrated with self-reduction, and further utilized as the novel catalysts to degrade 4-chlorophenol (4-CP) by coupling with peroxymonosulfate (PMS). Three optimized parameters (CFNC-30 NPs dosage of 0.089 g L-1, PMS concentration of 1.1 g L-1, and initial pH of 6.6) were obtained via response surface methodology by using the Box-Behnken design model. Benefiting from the larger specific surface area, pore-volume, and existence of abundant hydroxyl groups, CFNC-30 NPs with more available active sites exhibited an excellent efficiency of 99.1% toward catalytic degradation of 4-CP within 30 min under the optimal conditions. Moreover, CFNC-30 NPs demonstrated durability and long-term stability even during the five consecutive cycle tests without a significant drop in its catalytic performance. The scavenging experiments and electron paramagnetic resonance technologies revealed that non-radical singlet oxygen (1O2), sulfate radicals (SO4-), and hydroxyl radicals (HO) were involved as active species in the CFNC-30/PMS system, contributing 46.8, 35.6, and 17.6% efficiency toward 4-CP degradation, respectively. Besides, the reaction mechanism on the CFNC-30 NPs and degradation pathways toward 4-CP were speculated under PMS activation. The results indicated that the synergistic effects between zero-valent Co-Fe and NC structures not only significantly boosted the removal efficiency and long-term stability of CFNC-30 NPs, but also facilitated the redox cycles of Co3+/Co2+ and Fe3+/Fe2+. This proof-of-concept approach to develop such high-efficient zero-valent Co-Fe encapsulated in NC structures opens up novel avenues for wastewater decontamination via PMS activation.

3.
Life Sci ; 254: 117699, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32437793

RESUMO

AIMS: Ischemia/reperfusion (I/R) injury largely limits the efficacy of revascularization in acute myocardial infarction. Long noncoding RNA (lncRNA) Oprm1 is protective in cerebral I/R injury. This study aimed to investigate the effect of lncRNA Oprm1 on myocardial I/R injury and its mechanism. MAIN METHODS: We ligated and then released the left anterior descending coronary artery of adult male rats to build the I/R model in vivo. At the same time, an H9c2 cardiomyocytes hypoxia-reoxygenation (H/R) model was also used. Myocardial infarction area, cardiac function, histology, TUNEL staining, cell viability, and vital protein expression was conducted and compared. KEY FINDINGS: LncRNA Oprm1 was significantly down-regulated in the I/R injury model. When administered with the AAV9-Oprm1 vector, the myocardial injury and cardiac function were mitigated and preserved, with apoptosis reduced. The cystathionine-γ-lyase (CSE) expression and hydrogen sulfide (H2S) expression were increased. The dual-luciferase reporter gene revealed the targeted relationship between lncRNA Oprm1 and miR-30b-5p. In H9c2 cardiomyocytes models, the miR-30b-5p blocked the protective effect of lncRNA Oprm1 on H/R injury, when Bcl-2, Bcl-xl was down-regulated, and HIF-1α, Bnip-3, Caspase-3, and Caspase-9 up-regulated. SIGNIFICANCE: LncRNA Oprm1can competitively combines with miR-30b-5p, which down-regulates the expression of CSE. When administered with lncRNA Oprm1, increased endogenous H2S can reduce apoptosis and protect the myocardium from I/R injury via activating PI3K/Akt pathway and inhibiting HIF1-α activity.

4.
Ecotoxicol Environ Saf ; 195: 110375, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200142

RESUMO

Microbial immobilization is a novel and environmentally friendly technology that uses microbes to reduce metal availability in soil and accumulation of heavy metals in plants. We used urea agar plates to isolate urease-producing bacteria from the rhizosphere soil of pakchoi in Cd- and Pb-contaminated farmland and investigated their effects on Cd and Pb accumulation in pakchoi and the underlying mechanisms. The results showed that two urease-producing bacteria, Bacillus megaterium N3 and Serratia liquefaciens H12, were identified by screening. They had higher ability to produce urease (57.5 ms cm-1 min-1 OD600-1 and 76.4 ms cm-1 min-1 OD600-1, respectively). The two strains allowed for the immobilization of Cd and Pb by extracellular adsorption, bioprecipitation, and increasing the pH (from 6.94 to 7.05-7.09), NH4+ content (69.1%-127%), and NH4+/NO3- ratio (from 1.37 to 1.67-2.11), thereby reducing the DTPA-extractable Cd (35.3%-58.8%) and Pb (37.8%-62.2%) contents in the pakchoi rhizosphere soils and the Cd (76.5%-79.7%) and Pb (76.3%-83.5%) contents in the leaves (edible tissue) of pakchoi. The strains were highly resistant to heavy metal toxicity; produced IAA, siderophores and abscisic acid; and increased the NH4+/NO3- ratio, which might be related to the two strains protectiing pakchoi against the toxic effect of Cd and Pb and increasing pakchoi biomass. Thus, the results were supposed to strain resources and a theoretical basis for the remediation of Cd- and Pb-contaminated farmlands for the safe production of vegetables.

5.
J Viral Hepat ; 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32187804

RESUMO

The performances of routine tests such as FIB-4 and APRI in detecting cirrhosis and significant fibrosis in chronic hepatitis B (CHB) have been shown to be discrepant between studies. Novel tests such as red cell distribution width-platelet ratio (RPR), γ-glutamyl transpeptidase to platelet ratio (GPR) and easy liver fibrosis test (eLIFT) are introduced recently. To evaluate the aminotransferase influence on the performance of these routine tests, a total of 1005 CHB patients who underwent liver biopsies and routine tests were retrospectively analysed. The diagnostic cut-offs referring to likelihood ratio were determined for excluding or including cirrhosis diagnosis and also for ruling in significant fibrosis diagnosis. The performances of RPR, FIB-4, eLIFT and APRI in detecting cirrhosis seemed improved at higher ALT levels, while GPR was conversely impaired. The likelihood ratio was âˆ for APRI cut-off 2 diagnosing cirrhosis in ALT < 2 upper limit of normal (ULN), 14.6 for APRI cut-off 1.5 determining significant fibrosis in ALT ≤ 5ULN and 20.6 for FIB-4 cut-off 3.2 diagnosing ≥ F3 in the total cohort, respectively. The optimal cut-offs for cirrhosis diagnosis were increased with higher ALTs by tests which included aminotransferase, but not for RPR. The proportions of patients classified as having cirrhosis or no cirrhosis stratified by ALT level cut-offs were superior. Stepwise applying RPR, GPR and eLIFT would determine 60% of patients as having cirrhosis or no cirrhosis with an accuracy of 93.0%. In conclusion, the performance of aminotransferase comprising tests in detecting cirrhosis in CHB were influenced by ALT levels. Thus, ALT stratified cut-offs may be a preferred alternative. In resource-limited settings, stepwise applying routine tests could be recommended as a preferred measurement for cirrhosis detection.

6.
Bioresour Technol ; 304: 123026, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32127244

RESUMO

The potential of low-cost bioenergy recovery from peanut shell was limited for its complex cellulose structure. In order to enhance the total reducing sugar (TRS) yield for bio-H2 production, peanut shell with heat (HT, 50-100 °C) or freezing pretreatment (FT, -80 to 0 °C) under different duration (0.5-12 h) was investigated. For uncovering the enhancement mechanisms, morphological feature and crystalline structure were analyzed by scanning electron microscope (SEM) and X-ray powder diffraction (XRD). The optimal pretreatment of 50 °C for 12 h was obtained with TRS yield increased 73.6%, while the H2 yield of 1.25 ml/mg-TRS was peaked with pretreatment at -80 °C. The SEM and XRD further demonstrated that mechanisms of HT and FT were realized through different ways, which were cracking and collapsing in HT, and delamination and peeling in FT, respectively.


Assuntos
Arachis , Celulose , Hidrólise , Temperatura , Difração de Raios X
7.
Phys Rev Lett ; 124(3): 030502, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32031864

RESUMO

Communication in a network generally takes place through a sequence of intermediate nodes connected by communication channels. In the standard theory of communication, it is assumed that the communication network is embedded in a classical spacetime, where the relative order of different nodes is well defined. In principle, a quantum theory of spacetime could allow the order of the intermediate points between sender and receiver to be in a coherent superposition. Here we experimentally realize a tabletop simulation of this exotic possibility on a photonic system, demonstrating high-fidelity transmission of quantum information over two noisy channels arranged in a superposition of two alternative causal orders.

8.
Life Sci ; 246: 117419, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32045592

RESUMO

AIMS: Although resistin-like molecule ß (RELM-ß) is involved in the pathological processes of various lung diseases, such as pulmonary inflammation, asthma and fibrosis, its potential roles in hypoxic pulmonary arterial hypertension (PAH) remain largely unknown. The study aims to investigate whether RELM-ß contributes to hypoxia-induced excessive proliferation of human pulmonary artery smooth muscle cells (PASMCs) and to explore the potential mechanisms of this process. MAIN METHODS: Human PASMCs were exposed to normoxia or hypoxia (1% O2) for 24 h. siRNA targeting RELM-ß was transfected into cells. Protein levels of KCNK3, RELM-ß, pSTAT3 and STAT3 were determined by immunoblotting. The translocation of NFATc2 and expression of KCNK3 were visualized by immunofluorescence. 5-ethynyl-2'-deoxyuridine assays and cell counting kit-8 assays were performed to assess the proliferation of PASMCs. KEY FINDINGS: (1) Chronic hypoxia significantly decreased KCNK3 protein levels while upregulating RELM-ß protein levels in human PASMCs, which was accompanied by excessive proliferation of cells. (2) RELM-ß could promote human PASMCs proliferation and activate the STAT3/NFAT axis by downregulating KCNK3 protein under normoxia. (3) Inhibition of RELM-ß expression effectively prevented KCNK3-mediated cell proliferation under hypoxia. (4) Phospholipase C (PLC) inhibitor U-73122 could not only prevent the hypoxia/RELM-ß-induced decrease in KCNK3 protein, but also inhibit the enhanced cell viability caused by hypoxia/RELM-ß. (5) Both hypoxia and RELM-ß could downregulate membrane KCNK3 protein levels by enhancing endocytosis. SIGNIFICANCE: RELM-ß activation is responsible for hypoxia-induced excessive proliferation of human PASMCs. Interfering with RELM-ß may alleviate the progression of hypoxic PAH by upregulating PLC-dependent KCNK3 expression.


Assuntos
Hipóxia/complicações , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Fosfolipases Tipo C/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Imunofluorescência , Humanos , Hipóxia/tratamento farmacológico , Músculo Liso Vascular/citologia , Músculo Liso Vascular/crescimento & desenvolvimento , Artéria Pulmonar/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais
9.
J Antibiot (Tokyo) ; 73(5): 324-328, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32051568

RESUMO

Lavanducyanin is a bioactive phenazine-containing secondary metabolite, and naphthomevalin is an antibacterial polyketide secondary metabolite. Herein, new analogues of lavanducyanin (2) and of naphthomevalin (4), together with lavanducyanin (1) and naphthomevalin (3), were identified from Streptomyces sp. CPCC 203577, an actinomycete soil isolate. The structures of 2 and 4 were elucidated as 1-hydroxy-7-oxolavanducyanin and Δ7″,8″-6″-hydroxynaphthomevalin, respectively, by 1D and 2D NMR. Antibacterial assays revealed that 2 had significant but reduced anti-Gram-positive bacterial activity compared with 1, and 4 was devoid of anti-Gram-positive bacterial activity. This indicated that the phenazinone nucleus in lavanducyanin and the monoterpene side chain in naphthomevalin might be important for their anti-Gram-positive bacterial activity. Compounds 1-4 were all inactive against Gram-negative bacteria.

10.
Sci Rep ; 10(1): 2918, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075995

RESUMO

Microbial flocculant (MBF), an environmentally friendly water treatment agent, can be widely used in various water treatments. However, its use is limited by low yield and high cost. This problem can be solved by clarifying its biosynthesis mechanism and regulating it. Paenibacillus shenyangensis A9, a flocculant-producing bacterium, was used to produce polysaccharide-type MBFA9 by regulating the nitrogen source (nitrogen adequacy/nitrogen deficiency). In this study, RNA-Seq high-throughput sequencing technology and bioinformatic approaches were used to investigate the fermentation and biosynthesis of polysaccharide-type MBFA9 by regulating the nitrogen source (high nitrogen/low nitrogen) in the flocculant-producing bacteria Paenibacillus shenyangensis A9. Differentially expressed genes, functional clustering, and functional annotation of key genes were assessed. Then the MBFA9 biosynthesis and metabolic pathway were reconstructed. Our results showed that when cultured under different nitrogen conditions, bacterial strain A9 had a greater ability to synthesize polysaccharide-type MBFA9 under low nitrogen compared to high nitrogen conditions, with the yield of MBFA9 reaching 4.2 g/L at 36 h of cultivation. The quality of transcriptome sequencing data was reliable, with a matching rate of 85.38% and 85.48% when L36/H36 was mapped to the reference genome. The total expressed genes detected were 4719 and 4730, with 265 differentially expressed genes. The differentially expressed genes were classified into 3 categories: molecular function (MF), cell component (CC), and biological process (BP), and can be further divided into 22 subcategories. There were 192 upregulated genes and 73 downregulated genes, with upregulation being predominant under low nitrogen. UDP-Gal, UDP-Glc, UDP-GlcA, and UDP-GlcNAc, which are in the polysaccharide metabolic pathway, could all be used as precursors for MBFA9 biosynthesis, and murA, wecB, pgm, galU/galF, fcl, gmd, and glgC were the main functional genes capable of affecting the growth of bacteria and the biosynthesis of MBF. Results from this study provide evidence that high-level expression of key genes in MBFA9 biosynthesis, regulation, and control can achieve MBFA9 directional synthesis for large-scale applications.

11.
Aquat Toxicol ; 220: 105407, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945654

RESUMO

ZnO nanoparticles (NPs) form binary mixtures of ZnO particles and released Zn2+ in the environment, and the quantitative contributions of these components to toxicity are still uncertain. Herein, quantitative contribution of ZnO particle and Zn2+ to cytotoxicity of ZnO NPs to Escherichia coli were determined during 48 h bioassay. The cytotoxicity and mechanisms of ZnO NPs were dynamic and affected by ionic strength, Fe3+, humic acid, and temperature due to the unfixed ZnO particle:Zn2+ ratio. ZnO NPs and ZnO bulk particles (BPs) had comparable cytotoxicity but distinct cytotoxic mechanisms. ZnO NPs cytotoxicity arises mainly from ZnO particles for 3 h and from Zn2+ afterwards (8-48 h). The cytotoxicity of ZnO BPs depends predominantly on ZnO particles for 12 h and on Zn2+ from 24 to 48 h. The cytotoxicity of ZnO NPs and BPs is partially attributable to Zn accumulation, and dependent on ZnO particle:Zn2+ ratio. The linear regressions of acute toxicity for ZnO NPs vs. BPs and Zn2+ yielded excellent r2 (0.9994 and 0.9998) from literature data and good r2 (≥ 0.714) under certain environmental factors, which can be applied to assess environmental risk of ZnO NPs. Furthermore, dynamic cytotoxicity and mechanisms should be seriously considered during the environmental risk assessment of ZnO NPs.


Assuntos
Escherichia coli/efeitos dos fármacos , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Escherichia coli/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Nanopartículas/metabolismo , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/metabolismo
12.
Chemosphere ; 242: 125244, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896184

RESUMO

Efficient wastewater restoration depends on the robustness and capability of the catalyst to promote sophisticated decontamination technologies. In this study, Co3Fe7-CoFe2O4 nanoparticles (NPs) prepared by facile pyrolysis were completely characterized and used to decompose 2,4-dichlorophenol (2,4-DCP). Furthermore, the catalytic performance and relevant mechanisms involved in the activation of peroxymonosulfate (PMS) were also investigated. The optimal conditions were achieved at the catalyst loading of 0.05 g L-1, PMS dosage of 1.26 g L-1, and pH of 7.7 through the response surface methodology by using the Box-Behnken design model. Under optimal conditions, 97.1% efficiency of 2,4-DCP removal was obtained within 30 min. Moreover, the quenching experiments and electron paramagnetic resonance result indicated that sulfate (SO4•-) and hydroxyl (HO•) radicals were considered as the dominant reactive oxygen species, which resulted in the effective removal of 2,4-DCP in the Co3Fe7-CoFe2O4/PMS system. Moreover, Co3Fe7-CoFe2O4 showed efficient catalytic performance in continuous five runs and exhibited less metal leaching of 0.052 and 0.036 mg L-1 for Co and Fe species, respectively. Furthermore, no considerable change was observed in the structural characteristics of the fresh and used Co3Fe7-CoFe2O4 catalytic system. The above-mentioned results indicated that the synergistic effects between Co3Fe7 alloy and CoFe2O4 spinel not only significantly improved the activity and long-term durability of the catalyst, but also accelerated the Co3+/Co2+ and Fe3+/Fe2+ redox cycles. Overall, the Co3Fe7-CoFe2O4/PMS system provides a novel advanced oxidation approach to further develop multifunctional transition metal-based nanomaterials responsible for producing surface-bound radicals and enhancing the remediation of refractory pollutants in the environmental application.


Assuntos
Óxido de Alumínio/química , Clorofenóis/química , Óxido de Magnésio/química , Peróxidos/química , Eliminação de Resíduos Líquidos/métodos , Ligas , Catálise , Nanopartículas/química , Oxirredução , Fenóis , Águas Residuárias
13.
Appl Microbiol Biotechnol ; 104(1): 277-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31728583

RESUMO

The most wide-spread "hostile" environmental factor for marine microorganisms is low temperature, which is usually accompanied by high hydrostatic pressure (HHP). Metabolic mechanisms of marine microorganisms adapting to prolonged low temperature under HHP remain to be clarified. To reveal the underlying metabolic mechanisms, we performed NMR-based metabolomic analysis of aqueous extracts derived from a psychrotolerant Microbacterium sediminis YLB-01, which was isolated from deep-sea sediment and possess great biotechnology potentials. The YLB-01 cells were firstly cultivated at the optimal condition (28 °C, 0.1 MPa) for either 18 h (logarithmic phase) or 24 h (stationary phase), then continually cultivated at either 28 °C or 4 °C under HHP (30 MPa) for 7 days. The cells cultivated at low temperature, which experienced cold stress, were distinctly distinguished from those at normal temperature. Cold stress primarily induced metabolic changes in amino acid metabolism and carbohydrate metabolism. Furthermore, the logarithmic and stationary phase cells cultivated at low temperature exhibited distinct metabolic discrimination, which was mostly reflected in the significantly disturbed carbohydrate metabolism. The logarithmic phase cells displayed suppressed TCA cycle, while the stationary phase cells showed decreased pyruvate and increased lactate. In addition, we performed transcriptome analysis for the stationary phase cells to support the metabolomic analysis. Our results suggest that the cold adaptation of the psychrotroph YLB-01 is closely associated with profoundly altered amino acid metabolism and carbohydrate metabolism. Our work provides a mechanistic understanding of the metabolic adaptation of marine psychrotrophs to prolonged low temperature under HHP.

14.
Phys Rev Lett ; 123(17): 170402, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31702255

RESUMO

In a measurement-device-independent or quantum-refereed protocol, a referee can verify whether two parties share entanglement or Einstein-Podolsky-Rosen (EPR) steering without the need to trust either of the parties or their devices. The need for trusting a party is substituted by a quantum channel between the referee and that party, through which the referee encodes the measurements to be performed on that party's subsystem in a set of nonorthogonal quantum states. In this Letter, an EPR-steering inequality is adapted as a quantum-refereed EPR-steering witness, and the trust-free experimental verification of higher dimensional quantum steering is reported via preparing a class of entangled photonic qutrits. Further, with two measurement settings, we extract 1.106±0.023 bits of private randomness per every photon pair from our observed data, which surpasses the one-bit limit for projective measurements performed on qubit systems. Our results advance research on quantum information processing tasks beyond qubits.

15.
Bioresour Technol ; 294: 122140, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31557654

RESUMO

Limited nitrogen removal capacity (mainly nitrate, NO3--N) remains a major challenge for subsurface wastewater infiltration system (SWIS). Two nitrogen-removing strains have been isolated from SWIS and inoculated to SWIS to investigate the effect of bioaugmentation on nitrogen removal performance and mechanism. The results showed bioaugmentation improved the removal efficiencies of NH4+-N from 86.81% to 92.86% and TN from 74.90% to 86.55% and running stability compared to unbioaugmentation SWIS. 16 s rRNA amplicon sequencing results of the bacterial indicated that bioaugmentation altered the microbial community structure especially at 150 cm depth and increased the relative abundance of bacteria associated with nitrogen removal, significantly increasing the abundance of Rhizobiales_Incertae_Sedis and Lachnospiraceae. Furthermore, the relation between internal microbial characteristics and operational factors indicated that Hyphomicrobiaceae and Gemmatimonadaceae were also closely related to nitrogen removal. Predicted function profiles revealed that bioaugmentation enhanced the activity of nitrogen removal enzymes (Hao, NorBC, NasAB, NarGHI, NirBD and NosZ).


Assuntos
Microbiota , Águas Residuárias , Bactérias , Desnitrificação , Nitrogênio , Eliminação de Resíduos Líquidos
16.
Insects ; 10(9)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500284

RESUMO

Propoxur-sel strains of Culex pipiens quinquefasciatus were derived from a lab-bred strain following 16 generations of propoxur exposure under sublethal concentrations of LC25 (lethal concentration of 25%) and LC50 (lethal concentration of 50%), respectively. This resulted in resistance development in F16 with ratios of 8.8× and 6.3×, respectively, compared with F0. The fecundity, longevity, sex ratio (F/M), and hatchability of the propoxur-exposed Cx. quinquefasciatus adult survivors and their offspring were decreased, with no effect on the emergence ratio and pupa survival rate. In addition, the intrinsic rates of increase (r), the net reproduction (R0), and the finite rate of increase (λ) of the Cx. quinquefasciatus offspring generations were also decreased significantly compared to F0. Correspondingly, the mean generation time (T) and the population double time (DT) in propoxur-sels were increased. Enhanced activities of cytochrome P450 monooxygenase and esterase were also observed in propoxur-sels, indicating that a detoxification mechanism might be responsible for resistance development in Cx. quinquefasciatus. Except for the three genes cyp4d42v1, cyp4c52v1, and cyp6aa9 which displayed a coincidence in some degree in different treatments, induction by different doses of propoxur and constitutive expression in different generations of propoxur-sel strains resulted in an inconsistent identification of the P450 genes probably related with resistance.

17.
Front Microbiol ; 10: 1963, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507570

RESUMO

Globally, mosquitoes are known to be competent vectors to various arboviruses that cause serious and debilitating diseases to humans and animals. Conversely, mosquitoes harbor a wide array of insect specific viruses (ISVs) that are generally neglected. Extensive characterization of these ISVs is important in understanding their persistence infection effect on host behavior and arbovirus transmission. Herein, we report first time isolation of Tanay virus (TANAV) isolate YN15_103_01 in Anopheles sinensis mosquitoes from Yunnan Province, China. Phylogenetically, the isolate's nucleotide identity had more than 14.47% variance compared to previous TANAV isolates, and it clustered into an independent branch within the genus Sandewavirus in the newly proposed taxon Negevirus. TANAV growth and high titers was attained in Aag2 cells (107 PFU/mL) but with no CPE observed up to 7 days.p.i. compared to C6/36 cells that exhibited extensive CPE at 48 h.p.i. with titers of 107 PFU/mL. Contrarywise, the viral isolate did not replicate in vertebrate cell lines. Electron microscopy analyses showed that its final maturation process takes place in the cell cytoplasm. Notably, the predicted viral proteins were verified to be corresponding to the obtained SDS-PAGE protein bands. Our findings advance forth new and vital knowledge important in understanding insect specific viruses, especially TANAV.

18.
J Nat Prod ; 82(8): 2337-2342, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31381332

RESUMO

AntiSMASH analysis of genome DNA of Streptomyces CPCC 204980, a soil isolate with potent antibacterial activity, revealed a gene cluster for polycyclic xanthones. A subsequent chemical study confirmed that the microorganism produced polycyclic xanthone cervinomycin A2 (1) and the new congeners cervinomycins B1-4 (2-5). The structures of 1-5 were determined by comprehensive analyses of MS and NMR data, which indicated that 2-5 featured a common dihydro-D ring in the polycyclic xanthone core moiety of their molecules. 2-5 are toxic to human cancer cells and active against Gram-positive bacteria.

19.
Arthritis Res Ther ; 21(1): 189, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426834

RESUMO

BACKGROUND: In clinical practice, discrimination between central nervous system (CNS) infections in patients with systemic lupus erythematosus (SLE) and neuropsychiatric lupus erythematosus (NPSLE) could be urgent and critical yet extremely challenging. Given this, this study aimed to investigate the clinical features and outcomes of infections in the CNS in patients with SLE and to establish a simplified scoring system for guiding the discrimination of CNS infections from NPSLE. METHODS: A total of 95 patients who were identified as having CNS infections among 8491 SLE patients between January 1992 and January 2018 were included in this retrospective study. NPSLE patients admitted at the same period were randomly selected for comparison. Key factors either clinically valuable or statistically significant for discriminating CNS infections from NPSLE were integrated to build a simplified scoring system. Another group of 22 SLE patients complicated with suspected newly onset of CNS infections or NPSLE admitted after January 2018 was enrolled to verify the utility of the scoring system. RESULTS: Sixty-three positive pathogens were identified in 59 patients of the total 95 CNS infection cases. Compared with the NPSLE group, the CNS infections group had a longer disease duration (21.0 [3.0-50.0] vs. 1.0 [0-22.0] months, P < 0.05), exhibited more fever (96.8% vs. 23.2%, P < 0.001) and polymorphonuclear leukocyte leukocytosis in the cerebrospinal fluid (CSF) (45.6% vs. 0.5%, P < 0.05), and had significantly decreased CSF glucose (2.0 ± 1.3 vs. 3.3 ± 0.9 mmol/L, P < 0.01), whereas hypocomplementemia seemed to be a strong hint of NPSLE (44.6% vs. 77.4%, P < 0.001). A simplified scoring system integrated with 8 key factors was established for guiding clinical differential diagnosis. By setting the cutoff value at 4 and verifying in a group of SLE patients complicated with newly occurred suspected CNS infection or NPSLE, a sensitivity of 85.7% and specificity of 93.3% with the area under the curve (AUC) being 0.93 (95%CI 0.80-1.00) were obtained. CONCLUSIONS: CNS infections are a fatal complication of SLE and can be difficult to discriminate from NPSLE. A simplified scoring system may help to make preliminary discrimination of CNS infections from NPSLE.

20.
Bioresour Technol ; 292: 121960, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437798

RESUMO

The effects of different frequencies of pulsed electric field (PEF) on the ANAMMOX process were investigated. The results showed that the intermediate frequency could dramatically enhance both the ANAMMOX bacterial activity and granule sludge stability at 16 ±â€¯1 °C The nitrogen removal efficiency of R1 (intermediate frequency) was significantly enhanced by 62.24% and 79.51% compared to R2 (lower frequency) and R3 (higher frequency), with a nitrogen loading rate of 6.84 kg Nm-3 d-1. In addition, the intermediate frequency could stimulate cells to secrete more extracellular polymeric substances (EPS) to sustain the granule sludge stability. The granule sludge disintegrated on days 55 and 35 in R2 and R3. The protein (PN)/polysaccharide (PS) ratios of R1 were 28.46% and 54.20% higher than R2 and R3, which was beneficial to granule sludge stability. This study showed that PEF could solve the problem of decreased ANAMMOX bacterial activity and granule stability at lower temperatures.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Bactérias , Nitrogênio , Oxirredução , Temperatura
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