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1.
Environ Res ; 251(Pt 2): 118652, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508361

RESUMO

Adsorption processes are being widely used by various researchers for the removal of heavy metals from waste streams and biochar has been frequently used as an adsorbent. In this study, a MgO-loaded biochar derived from Alternanthera philoxeroides (MAPB) was synthesized for the removal of Cu(II). Compared with other biochar absorbents, MAPB showed a relatively slow adsorption kinetics, but an effective removal of Cu(II) with a maximum sorption capacity of 1, 238 mg/g. The adsorption mechanism of Cu(II) by MAPB was mainly controlled by chemical precipitation as Cu2(OH)3NO3, complexation and ion replacement. Fixed bed column with MAPB packed in same dosage (1, 000 mg) and different bed depth (1.3, 2.6 and 3.9 cm) showed that the increased of bed depth by mixing MAPB with quartz sand could increase the removal of Cu(II). The fitted breakthrough (BT) models showed that mixing MAPB with support media could reduce the mass transfer rate, increase the dynamic adsorption capacity and BT time. Therefore, MAPB adsorbent act as a highly efficient long-term adsorbent for Cu(II) contaminated water treatment may have great ecological and environmental significance.


Assuntos
Amaranthaceae , Carvão Vegetal , Cobre , Poluentes Químicos da Água , Carvão Vegetal/química , Cobre/química , Amaranthaceae/química , Adsorção , Poluentes Químicos da Água/química , Magnésio/química , Cinética , Purificação da Água/métodos
2.
Front Oncol ; 13: 1257615, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841445

RESUMO

Objectives: We aimed to analyze the risk factors of elderly women with epithelial ovarian cancer (EOC) using data on the SEER database, and to generate a nomogram model their 1-, 3-, and 5-year prognoses. The resulting nomogram model should be useful for clinical diagnoses and treatment. Methods: We collected clinical data of women older than 70 years with epithelial ovarian cancer (diagnosed on the basis of surgical pathology) from the SEER database including datasets between 2010 and 2019. We randomly grouped the data into two groups (7:3 ratio) using the R language software. We divided the independent prognostic factors obtained by univariate and multi-factor Cox regression analyses into training and validation sets, and we plotted the same independent prognostic factors in a nomogram model of overall survival (OS) at 1, 3, and 5 years. We used the C-index, calibration curve, and area under the curve to validate the nomograms. We further evaluated the model and its clinical applicability using decision curve analyses. Results: We identified age, race, marital status, histological type, AJCC staging, differentiation degree, unilateral and bilateral tumor involvement, number of positive lymph nodes, chemotherapy, surgery, sequence of systemic treatment versus surgery, and time from diagnosis to treatment as independent prognostic factors for elderly women with EOC (P < 0.5). The C-indexes were 0.749 and 0.735 in the training and validation sets, respectively; the ROC curves showed that the AUC of each prognostic factor was greater than 0.7; and, the AUC values predicted by the line plot were similar in the training and validation sets. The decision curves suggest that this line plot model has a high clinical value for predicting overall survivals at 1, 3, and 5 years in elderly women with EOC. Conclusion: The nomogram model in this study can provide an accurate assessment of the overall survival of women older than 70 years with EOC at the time of the first treatment, and it provides a basis for individualized clinical treatment.

3.
Sci Total Environ ; 896: 165096, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37355123

RESUMO

Sustained nitrate accumulation in surface water ecosystem was continuously grabbing public attention. Autotrophic denitrification by electron supplement has been applied to overcome the requirement of carbon source, thus the new problem that how to improve the efficiency of extracellular electrons transfer to denitrifiers comes to us. The addition of exogenous electron mediators has been considered as an important strategy to promote extracellular electrons transfer in reductive metabolism. To date, knowledge is lacking about the promoting effects and pathways in nitrate removal by electron mediators. Here, we fully investigated the performance of nitrogen removal as well as quantified the characteristics of biofilms with six electron mediators (riboflavin, flavin mononucleotide, AQS, AQDS, biochar and Nano-Fe3O4) treating in microbial electrolytic cell system. The six electron mediators promoted nitrate removal rate by 76.03-90.43 % with electron supplement. The growth and activity of cathodic biofilm, conductive nanowires generation and electrochemically active substance synthesis of extracellular polymeric substances were facilitated by electron mediator addition. Electrochemical analysis revealed that conductivity and redox capacity of cathodic biofilm was increased for accelerating electron transfer. Moreover, they upregulated the abundance of denitrifying communities and denitrifying genes accordingly. Their denitrification efficiency varied due to their promotion ability in the above different strategies and conductive characteristics, and the efficiency could be concluded as: Nano-Fe3O4 > riboflavin > flavin mononucleotide > AQS ≈ AQDS > biochar. This study revealed how addition of electron mediators promoted denitrification with electron supplement, and compared their promoting efficiency in several main aspects.


Assuntos
Elétrons , Nitratos , Nitratos/metabolismo , Desnitrificação , Mononucleotídeo de Flavina/metabolismo , Mononucleotídeo de Flavina/farmacologia , Ecossistema , Reatores Biológicos , Nitrogênio/farmacologia
4.
J Hazard Mater ; 445: 130438, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36446313

RESUMO

Deep dewatering of waste activated sludge (WAS) is still a challenge due to high content of bound water and non-Newton fluid properties of sludge flocs. Electro-Fenton (EF) can enhance sludge dewaterability, however, low pH needed in homogeneous EF and fine flocs after EF conditioning influenced deep dewatering of sludge and the subsequent resource recovery disposal. In this study, a three dimension electro-Fenton (3D-EF) using Fe modified sludge biochar (Fe@SBC) as particle electrode, heterogeneous Fenton catalyst and skeleton builder for deep dewatering of sludge under neutral pH was proposed. Fe@SBC obtained at 800 °C exhibited high capacity of H2O2 electrogeneration and activation due to high conductivity and content of 2e-ORR selectivity functional groups. With promoted generation of H2O2 and hydroxyl radical (•OH), 3D-EF with Fe@SBC showed higher decomposition of bound extracellular polymeric substances (EPS) and disintegration of cells in sludge flocs, resulting in releasing bound and intracellular water into free water. Compared with EF, 3D-EF with Fe@SBC800 had higher ability in breaking macromolecules of protein and polysaccharide, as well as removing -COOH and -NH2 groups in EPS, which could facilitate release of bound water trapped in EPS and self-coagulation of fine flocs. During subsequent filtering process, Fe@SBC could enhance sludge filterability as skeleton builder. A synergetic effect of strong oxidation and physical conditioning were proposed in 3D-EF sludge dewaterability with Fe@SBC, and the improved oxidation by Fe@SBC was supposed to play the major role.


Assuntos
Peróxido de Hidrogênio , Ferro , Peróxido de Hidrogênio/química , Ferro/química , Esgotos/química , Oxirredução , Água/química , Eliminação de Resíduos Líquidos/métodos
5.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080869

RESUMO

In this paper, we present a new microfluidic microwave sensor loaded with a star-slotted patch for detecting the quality of edible oil. The relative dielectric permittivity and the quality of edible oil will change after being heated at a high temperature. Therefore, the quality of edible oil can be detected by measuring the relative dielectric permittivity of edible oil. The sensor is used to determine the edible oil with different dielectric permittivity by measuring the resonance frequency offset of the input reflection coefficient, which operates at 2.68 GHz. This sensor is designed based on a resonant approach to provide the best sensing accuracy and is implemented using a substrate integrated waveguide structure combined with a pentagonal slot antenna operating at 2.3~2.9 GHz. It can detect greasy liquids with the real part of the complex permittivity ranging from two to three.


Assuntos
Microfluídica , Micro-Ondas
6.
J Hazard Mater ; 429: 128354, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123130

RESUMO

The ß-lactam antibiotic meropenem (MEM) is widely used in infectious disease treatment and consequently can be released into the environment, causing environmental pollution. In this study, Pseudomonas putida strain R51 was isolated from the wastewater of a poultry farm and found to efficiently degrade MEM. The genome of strain R51 contains a variety of heavy metal and antibiotic resistance genes, including the metallo-ß-lactamase gene (JQN61_03315) and cadmium resistance gene cadA (JQN61_19995). Under cadmium stress, the degradation rate of MEM increased significantly in strain R51. Transcriptional analysis revealed that the expression of JQN61_03315 and cadA significantly increased under cadmium stress and that the expression of many genes associated with heavy metal and antibiotic resistance also changed significantly. Molecular docking analysis suggested that metallo-ß-lactamase JQN61_03315 binds to MEM. In addition, no plasmid was found in strain R51, and no mobile genetic elements were found nearby JQN61_03315. In conclusion. we proposed that JQN61_03315 was responsible for the degradation of MEM, that the expression of this gene was induced under cadmium stress, and that strain R51 can be used for bioremediation of MEM without the risk for the transmission of the MEM resistance gene. These findings will have importance for studying the microbial degradation of MEM in the presence of heavy metal pollutants.


Assuntos
Pseudomonas putida , Antibacterianos/farmacologia , Cádmio/metabolismo , Cádmio/toxicidade , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , beta-Lactamases/genética , beta-Lactamases/metabolismo
7.
Microbiol Spectr ; 9(3): e0200521, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34937181

RESUMO

Antibiotic resistance genes (ARGs) and horizontal transfer of ARGs among bacterial species in the environment can have serious clinical implications as such transfers can lead to disease outbreaks from multidrug-resistant (MDR) bacteria. Infections due to antibiotic-resistant Chryseobacterium and Elizabethkingia in intensive care units have been increasing in recent years. In this study, the multi-antibiotic-resistant strain Chryseobacterium sp. POL2 was isolated from the wastewater of a livestock farm. Whole-genome sequencing and annotation revealed that the POL2 genome encodes dozens of ARGs. The integrative and conjugative element (ICE) ICECspPOL2, which encodes ARGs associated with four types of antibiotics, including carbapenem, was identified in the POL2 genome, and phylogenetic affiliation analysis suggested that ICECspPOL2 evolved from related ICEEas of Elizabethkingia spp. Conjugation assays verified that ICECspPOL2 can horizontally transfer to Elizabethkingia species, suggesting that ICECspPOL2 contributes to the dissemination of multiple ARGs among Chryseobacterium spp. and Elizabethkingia spp. Because Elizabethkingia spp. is associated with clinically significant infections and high mortality, there would be challenges to clinical treatment if these bacteria acquire ICECspPOL2 with its multiple ARGs, especially the carbapenem resistance gene. Therefore, the results of this study support the need for monitoring the dissemination of this type of ICE in Chryseobacterium and Elizabethkingia strains to prevent further outbreaks of MDR bacteria. IMPORTANCE Infections with multiple antibiotic-resistant Chryseobacterium and Elizabethkingia in intensive care units have been increasing in recent years. In this study, the mobile integrative and conjugative element ICECspPOL2, which was associated with the transmission of a carbapenem resistance gene, was identified in the genome of the multi-antibiotic-resistant strain Chryseobacterium sp. POL2. ICECspPOL2 is closely related to the ICEEas from Elizabethkingia species, and ICECspPOL2 can horizontally transfer to Elizabethkingia species with the tRNA-Glu-TTC gene as the insertion site. Because Elizabethkingia species are associated with clinically significant infections and high mortality, the ability of ICECspPOL2 to transfer carbapenem resistance from environmental strains of Chryseobacterium to Elizabethkingia is of clinical concern.


Assuntos
Antibacterianos/farmacologia , Chryseobacterium/efeitos dos fármacos , Chryseobacterium/genética , Farmacorresistência Bacteriana Múltipla , Infecções por Flavobacteriaceae/microbiologia , Flavobacteriaceae/efeitos dos fármacos , Flavobacteriaceae/genética , Chryseobacterium/classificação , Chryseobacterium/isolamento & purificação , Conjugação Genética , Flavobacteriaceae/classificação , Flavobacteriaceae/isolamento & purificação , Transferência Genética Horizontal , Genoma Bacteriano , Humanos , Filogenia , Águas Residuárias/microbiologia
8.
J Glob Antimicrob Resist ; 27: 20-25, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34365056

RESUMO

OBJECTIVES: Multidrug-resistant (MDR) Stenotrophomonas maltophilia strain MER1 was isolated from hospital wastewater in Shandong Province, China. This study aimed to determine the genetic determinants related to its striking MDR phenotype. METHODS: Antimicrobial susceptibility testing of strain MER1 was performed by disk diffusion on Mueller-Hinton agar plates, and MICs were interpreted according to Clinical and Laboratory Standards Institute breakpoints. The genome of MER1 was sequenced and assembled using PacBio RS II and BGISEQ-500 platforms. Antimicrobial resistance determinants together with other transferability or adaptability determinants were identified by comparative genomics. Phylogenetic and contextual assays for these elements were conducted to assess the risk of spread of MER1. RESULTS: Antimicrobial susceptibility testing revealed that strain MER1 is resistant to nine different antibiotics, including ampicillin, meropenem, amikacin, erythromycin, vancomycin, tetracycline, tigecycline, colistin and ceftazidime. Several genes were identified encoding efflux pumps and drug-inactivating agents, accounting for resistance to the above antibiotics, including meropenem, tigecycline and colistin regarded as last-line therapies for infections caused by MDR Gram-negative bacteria. MER1 co-harbours two non-mobile mcr homologues. A novel genomic region of variability was demonstrated to confer bacterial robustness and adaptability upon strain MER1. CONCLUSION: Collective efforts revealed the MDR properties and potential genetic determinants of S. maltophilia MER1 isolated from hospital wastewater. Comparative genomic analysis of S. maltophilia MER1 may provide insights into the prevention and treatment of antimicrobial-resistant infections. Our findings raise concern that the MDR genes in the reservoir of S. maltophilia may further spread into various ecological niches or medically high-risk pathogens.


Assuntos
Stenotrophomonas maltophilia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana , Filogenia , Stenotrophomonas maltophilia/genética
9.
J Pharm Pharmacol ; 73(7): 937-946, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33963858

RESUMO

OBJECTIVES: Loratadine is a selective H1 receptor inhibitor that has been widely used in the clinical treatment of allergic diseases. Here we aimed to develop a novel solid loratadine nanocrystal to increase the low and pH-dependent water solubility for bioavailability enhancement. METHODS: Loratadine solid nanocrystal was developed through high-speed shear-high pressure homogenization followed by freeze-drying, which was further prepared into tablets through direct compression. The formulation and process parameter were screened. Furthermore, the characterization and oral bioavailability of loratadine nanocrystal were studied. KEY FINDINGS: The loratadine nanocrystal had the satisfactory particle size of 425.9 nm and great redispersibility, which was mainly attributed to the addition of Pluronic F127 and polyvinylpyrrolidone K17 as the stabilizer. The saturation solubility of the loratadine nanocrystal was increased to 3.81, 3.22 and 2.57-fold that of the crude drug in water, pH 6.8 and pH 4.5 buffer respectively. Furthermore, the pharmacokinetic studies in rats revealed that the AUC (0-∞) of the nanocrystal tablets was 2.38-fold that of raw tablets and 1.94-fold that of commercial tablets, respectively. CONCLUSIONS: The nanocrystal tablets could significantly improve the oral bioavailability of loratadine, which would also be a promising approach to enhance the solubility of insoluble drugs.


Assuntos
Composição de Medicamentos/métodos , Hipersensibilidade/tratamento farmacológico , Loratadina , Nanopartículas/química , Solubilidade , Disponibilidade Biológica , Excipientes/farmacologia , Liofilização , Antagonistas dos Receptores Histamínicos H1/farmacologia , Humanos , Loratadina/química , Loratadina/farmacocinética , Comprimidos
10.
3 Biotech ; 11(2): 104, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33552832

RESUMO

An innovative investigation was undertaken into the abundance and diversity of high antibiotic-resistant bacteria in aquaculture waters in Shandong Province, China, through cumulation incubation, PCR amplification of 16S rDNA, and high-throughput sequencing. The results showed that Vibrio, Bacillus, Vagococcus, Acinetobacter, Shewanella, Psychrobacter, Lactococcus, Enterococcus, Marinimonus and Myroids were abundant in the aquaculture waters, whereas other phylum including Actinobacteria, Deinococcus-Thermus, Omnitrophica and Nitrospirae had relatively lower abundance. Our studies revealed the presence of different bacteria in different locations in the aquaculture waters, most of which were resistant to multiple antibiotics. That is, the same microbial species from the same aquaculture wastewater can resist different antibiotics. Altogether, a considerable portion of the microbial community were found to be multi-drug resistant. It is essential that the spread of the antibiotic-resistant bacteria is controlled so that the distribution of antibiotic resistance genes to other environments is avoided. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02656-4.

11.
Front Microbiol ; 11: 616364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391249

RESUMO

Antibiotics and organoarsenical compounds are frequently used as feed additives in many countries. However, these compounds can cause serious antibiotic and arsenic (As) pollution in the environment, and the spread of antibiotic and As resistance genes from the environment. In this report, we characterized the 28.5 kb genomic island (GI), named as ICERspD18B, as a novel chromosomal integrative and conjugative element (ICE) in multidrug-resistant Rheinheimera sp. D18. Notably, ICERspD18B contains six antibiotic resistance genes (ARGs) and an arsenic tolerance operon, as well as genes encoding conjugative transfer proteins of a type IV secretion system, relaxase, site-specific integrase, and DNA replication or partitioning proteins. The transconjugant strain 25D18-B4 was generated using Escherichia coli 25DN as the recipient strain. ICERspD18B was inserted into 3'-end of the guaA gene in 25D18-B4. In addition, 25D18-B4 had markedly higher minimum inhibitory concentrations for arsenic compounds and antibiotics when compared to the parental E. coli strain. These findings demonstrated that the integrative and conjugative element ICERspD18B could mediate both antibiotic and arsenic resistance in Rheinheimera sp. D18 and the transconjugant 25D18-B4.

12.
Huan Jing Ke Xue ; 34(8): 2961-7, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24191536

RESUMO

To investigate the impact of experimental warming on N2O emission from soil of soybean field, outdoor experiments with simulating diurnal warming were conducted, and static dark chamber-gas chromatograph method was used to measure N2O emission fluxes. Results indicated that: the diurnal warming did not change the seasonal pattern of N2O emissions from soil. In the whole growing season, comparing to the control treatment (CK), the warming treatment (T) significantly enhanced the N2O flux and the cumulative amount of N2O by 17.31% (P = 0.019), and 20.27% (P = 0.005), respectively. The significant correlations were found between soil N2O emission and soil temperature, moisture. The temperature sensitivity values of soil N2O emission under CK and T treatments were 3.75 and 4.10, respectively. In whole growing stage, T treatment significantly increased the crop aboveground and total biomass, the nitrate reductase activity, and total nitrogen in leaves, while significantly decreased NO3(-) -N content in leaves. T treatment significantly increased soil NO3(-) -N content, but had no significant effect on soil organic carbon and total nitrogen contents. The results of this study suggested that diurnal warming enhanced N2O emission from soil in soybean field.


Assuntos
Glycine max , Óxido Nitroso/química , Solo/química , Temperatura , Biomassa , Nitrogênio/química , Folhas de Planta/química , Estações do Ano
13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1268-9, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125594

RESUMO

In the title compound, {(NH(4))(2)[Zn(C(8)H(6)O(8))]·4H(2)O}(n), the asymmetric unit contains one ammonium cation, half of a butane-1,2,3,4-tetra-carboxyl-ate anion, one Zn(2+) cation and two water mol-ecules. The butane-1,2,3,4-tetra-carboxyl-ate ligand is located about an inversion centre at the mid-point of the central C-C bond. The Zn(2+) cation is situated on a twofold rotation axis and is surrounded by four O atoms from four symmetry-related butane-1,2,3,4-tetra-carboxyl-ate anions in a distorted tetra-hedral environment. In turn, each anion coordinates to four Zn(2+) cations. The bridging mode of the anions leads to a three-dimensional framework structure with channels extending along [110] and [010] in which the ammonium cations and the water mol-ecules are located. N-H⋯O and O-H⋯O hydrogen bonding between the cations and water mol-ecules and the uncoordinating O atoms of the carboxyl-ate groups consolidates the crystal packing.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o3016, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125786

RESUMO

The r.m.s. deviation from the mean plane for the non-H atoms in the title compound, C(7)H(5)BrN(2)S, is 0.011 Å. In the crystal, the mol-ecules are linked by N-H⋯N and N-H⋯Br hydrogen bonds to generate (010) sheets. Weak aromatic π-π stacking [centroid-to-centroid separation = 3.884 (10) Å] and possible C-H⋯Br inter-actions are also observed. The crystal studied was found to be an inversion twin.

15.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2736, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969619

RESUMO

In the title compound, C(10)H(9)NO(3), the dihedral angle between the phenyl ring and the amide group is 10.8 (2)°. The C=O and O-H bonds of the carboxyl group adopt an anti orientation and an intra-molecular O-H⋯O hydrogen bond closes an S(7) ring. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(7) chains propagating in [101]. The packing is consolidated by C-H⋯O inter-actions, generating sheets aligned at an angle of ca 60° with the bc plane.

16.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3117, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284442

RESUMO

In the title mol-ecular salt, C(5)H(9)N(2) (+)·C(7)H(3)N(2)O(7) (-), the roughly planar anion (r.m.s. deviation = 0.120 Å) has been deprotonated at the phenol group. An intra-molecular O-H⋯O hydrogen bond in the anion generates an S(6) ring. In the crystal, the components are linked by cation-to-anion N-H⋯O and N-H⋯(O,O) hydrogen bonds, generating [010] double chains. Weak C-H⋯O inter-actions consolidate the packing.

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