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1.
Chemosphere ; 271: 129566, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33460896

RESUMO

Nitrogen amendment is known to effectively enhance the bioremediation of hydrocarbon-contaminated soil, but the nitrogen metabolism in this process is not well understood. To unravel the nitrogen metabolic pathway(s) of diesel contaminated soil, six types of nitrogen sources were added to the diesel contaminated soil. Changes in microbial community and soil enzyme genes were investigated by metagenomics analysis and chemical analysis through a 30-day incubation study. The results showed that ammonium based nitrogen sources significantly accelerated the degradation of total petroleum hydrocarbon (TPH) (79-81%) compared to the control treatment (38%) and other non-ammonium based nitrogen amendments (43-57%). Different types of nitrogen sources could dramatically change the microbial community structure and soil enzyme gene abundance. Proteobacteria and Actinobacteria were identified as the two dominant phyla in the remediation of diesel contaminated soil. Metagenomics analysis revealed that the preferred metabolic pathway of nitrogen was from ammonium to glutamate via glutamine, and the enzymes governing this transformation were glutamine synthetase and glutamate synthetase; while in nitrate based amendment, the conversion from nitrite to ammonium was restrained by the low abundance of nitrite reductase enzyme and therefore retarded the TPH degradation rate. It is concluded that during the process of nitrogen enhanced bioremediation, the most efficient nitrogen cycling direction was from ammonium to glutamine, then to glutamate, and finally joined with carbon metabolism after transforming to 2-oxoglutarate.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33176641

RESUMO

INTRODUCTION: Microglia-mediated inflammatory responses play a crucial role in aging-related neurodegenerative diseases. The TXNIP/NLRP3 pathway is a key pathway leading to microglial activation. Panax notoginseng saponins (PNS) have been widely used for the treatment of stroke in China. OBJECTIVE: This study evaluates the anti-neuroinflammatory effect of PNS and investigates the mechanism via TXNIPmediated NLRP3 inflammasome activation in aging rats. MATERIALS AND METHODS: Eighteen-month-old Sprague-Dawley rats were randomly divided into the aging control group and PNS treated groups (n=15 each group). For PNS-treated groups, rats were administrated food with PNS at the doses of 10 mg/kg and 30 mg/kg for consecutive 6 months until they were 24-month old. Rats from the aging control group were given the same food without PNS. Two-month-old rats were purchased and given the same food until 6-month old as the adult control group (n = 15). Then, the cortex and hippocampus were rapidly harvested and deposited. H&E staining was used to assess histo-morphological changes. Western blotting was carried out to detect the protein expression. Immunofluorescence was employed to measure the co-localization of NLRP3, TXNIP and Iba-1. In vitro model was established by LPS+ATP coincubation in the BV2 microglia cell line. RESULTS: Aging rats exhibited increased activation of microglia, accompanied by a high level of IL-1ß expression. Meanwhile, aging rats showed enhanced protein expression of TXNIP and NLRP3 related molecules, which co-localized with microglia. PNS treatment effectively reduced the number of degenerated neurons and reversed the activation of the TXNIP/NLRP3 inflammatory pathway. In vitro results showed that PNS up to 100 µg / ml had no significant toxicity on BV2 microglia. DISCUSSION: PNS (25, 50 µg/ml) effectively reduced the inflammatory response induced by LPS and ATP co-stimulation, thus inhibiting the expression of TXNIP/NLRP3 pathway-related proteins. CONCLUSION: PNS treatment improved aging-related neuronal damage through inhibiting TXNIP mediated NLRP3 inflammasome activation, which provided a potential target for the treatment of inflammatory-related neurodegenerative diseases.

3.
Sci Total Environ ; : 143667, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33248759

RESUMO

Soil fungal communities drive diverse ecological processes and are critical in maintaining ecosystems' stability, but the effects of plant invasion on soil fungal diversity, community composition, and functional groups are not well understood. Here, we investigated soil fungal communities in a salt marsh ecosystem with both native (Suaeda salsa) and exotic (Spartina alterniflora) species in the Yellow River Delta. We characterized fungal diversity based on the PCR-amplified Internal Transcribed Spacer 2 (ITS2) DNA sequences from soil extracted total DNA. The plant invasion evidently decreased fungal richness and phylogenetic diversity and significantly altered the taxonomic community composition (indicated by the permutation test, P < 0.001). Co-occurrence networks between fungal species showed fewer network links but were more assembled because of the high modularity after the invasion. As indicated by the fungal Bray-Curtis and weighted UniFrac distances, the fungal community became homogenized with the invasion. FUNGuild database analyses revealed that the invaded sites had a higher proportion of saprophytic fungi, suggesting higher organic matter decomposition potential with the invasion. The plant invasion dramatically inhibited the growth of pathogenic fungi, which may facilitate the expansion of invasive plants in the intertidal habitats. Soil pH and salinity were identified as the most important edaphic factors in shaping the fungal community structures in the context of Spartina alterniflora invasion. Overall, this study elucidates the linkage between plant invasion and soil fungal communities and poses potential consequences for fungal contribution to ecosystem function, including the decomposition of soil organic substrates.

4.
Environ Microbiol ; 2020 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-33073448

RESUMO

Soil salinity acts as a critical environmental filter on microbial communities, but the consequences for microbial diversity and biogeochemical processes are poorly understood. Here, we characterized soil bacterial communities and microbial functional genes in a coastal estuarine wetland ecosystem across a gradient (~5 km) ranging from oligohaline to hypersaline habitats by applying the PCR-amplified 16S rRNA (rRNA) genes sequencing and microarray-based GeoChip 5.0 respectively. Results showed that saline soils in marine intertidal and supratidal zone exhibited higher bacterial richness and Faith's phylogenetic diversity than that in the freshwater-affected habitats. The relative abundance of taxa assigned to Gammaproteobacteria, Bacteroidetes and Firmicutes was higher with increasing salinity, while those affiliated with Acidobacteria, Chloroflexi and Cyanobacteria were more prevalent in wetland soils with low salinity. The phylogenetic inferences demonstrated the deterministic role of salinity filtering on the bacterial community assembly processes. The abundance of most functional genes involved in carbon degradation and nitrogen cycling correlated negatively with salinity, except for the hzo gene, suggesting a critical role of the anammox process in tidal affected zones. Overall, the salinity filtering effect shapes the soil bacterial community composition, and soil salinity act as a critical inhibitor in the soil biogeochemical processes in estuary ecosystems.

5.
Antiviral Res ; 184: 104953, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33065138

RESUMO

BACKGROUND & AIMS: Normal/mildly elevated ALT (<2 × ULN) CHB patients are potentially at risk of progression to cirrhosis and/or hepatocellular carcinoma (HCC). We aimed to assess the outcomes of anti-viral therapy for normal/mild elevation of ALT CHB patients. METHODS: CHB patients (n = 432) who have had liver biopsied were determined. It was determined that the outcomes of anti-viral therapy in CHB patients with normal/mild elevation of ALT, in response to nucleoside/nucleotide analogues (NAs) (n = 190) and pegylated interferon (PEG-IFN) (n = 30) treatment for up to 72 weeks. Non-anti-viral treated patients were used as control (n = 40). RESULTS: There was about 50% of the CHB patients showed hepatic inflammatory necrosis ≥ G2 and/or fibrosis ≥ S2 among >30-years-old. The rate of undetectable HBV DNA in NAs and PEG-IFN groups was ~50%, ~80% or ~90% at week 24, 48 or 72, respectively. HBeAg clearance rate was lower in NAs treated than that in PEG-IFN group at week 48 (6% vs 20%, P < 0.05). ALT normalization rate was increased by 1.18-fold at week 72. HBsAg decline in HBeAg+ patients treated with NAs or PEG-IFN was 0.418 or 1.217 log IU/mL (P < 0.0001) at week 48; whereas HBsAg decline was 0.176 or 0.816 log IU/mL (P < 0.001) in HBeAg- patients. HBsAg at baseline and week 24 were strong predictors of "low HBsAg at week 48". CONCLUSION: Long term anti-viral therapy inhibits HBV replication effectively in ALT<2 × ULN CHB patients. PEG-IFN therapy is recommended for HBeAg+ patients with baseline HBsAg<4.37 log IU/ml and HBeAg- patients with baseline HBsAg<2.66 log IU/ml to achieve "low HBsAg at week 48".

6.
Nat Commun ; 11(1): 4211, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839440

RESUMO

Surface plasmons (SPs) of metals enable the tight focusing and strong absorption of light to realize an efficient utilization of photons at nanoscale. In particular, the SP-generated hot carriers have emerged as a promising way to efficiently drive photochemical and photoelectric processes under moderate conditions. In situ measuring of the transport process and spatial distribution of hot carriers in real space is crucial to efficiently capture the hot carriers. Here, we use electrochemical tip-enhanced Raman spectroscopy (EC-TERS) to in situ monitor an SP-driven decarboxylation and resolve the spatial distribution of hot carriers with a nanometer spatial resolution. The transport distance of about 20 nm for the reactive hot carriers is obtained from the TERS imaging result. The hot carriers with a higher energy have a shorter transport distance. These conclusions can be guides for the design and arrangement of reactants and devices to efficiently make use of plasmonic hot carriers.

7.
Acta Diabetol ; 57(11): 1383-1393, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32647998

RESUMO

AIMS: Steroid diabetes mellitus (SDM) is a metabolic syndrome caused by an increase in glucocorticoids, and its pathogenesis is unclear. 18F-FDG PET/CT can reflect the glucose metabolism of tissues and organs under living conditions. Here, PET/CT imaging of SDM and type 2 diabetes mellitus (T2DM) rats was used to visualize changes in glucose metabolism in the main glucose metabolizing organs and investigate the pathogenesis of SDM. METHODS: SDM and T2DM rat models were established. During this time, PET/CT imaging was used to measure the %ID/g value of skeletal muscle and liver to evaluate glucose uptake. The pancreatic, skeletal muscle and liver were analyzed by immunohistochemistry. RESULTS: SDM rats showed increased fasting blood glucose and insulin levels, hyperplasia of islet α and ß cells, increased FDG uptake in skeletal muscle accompanied by an up-regulation of PI3Kp85α, IRS-1, and GLUT4, no significant changes in liver uptake, and that glycogen storage in the liver and skeletal muscle increased. T2DM rats showed atrophy of pancreatic islet ß cells and decreased insulin levels, significantly reduced FDG uptake and glycogen storage in skeletal muscle and liver. CONCLUSIONS: The pathogenesis of SDM is different from that of T2DM. The increased glucose metabolism of skeletal muscle may be related to the increased compensatory secretion of insulin. Glucocorticoids promote the proliferation of islet α cells and cause an increase in gluconeogenesis in the liver, which may cause increased blood glucose.

8.
Sci Total Environ ; 742: 140124, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32623179

RESUMO

Increasing nitrogen deposition has become one of major environmental concerns in coastal wetlands. However, little is known about the response of soil nitrous oxide (N2O) emissions, a powerful greenhouse gas, to the different levels and forms of nitrogen addition, in salt-affected coastal soils. To close the knowledge gap, a laboratory factorial incubation experiment with four nitrogen addition levels (0, no N addition; low-N, 45; medium-N, 90; high-N, 270 mg N kg-1), three forms (NO3- (KN); NH4+ (NH); DN, NH4NO3 (DN)), and three levels of salt addition (0, no salt addition; 12 ppt, low-salt; 35 ppt, high-salt) was carried out in two coastal soils with different initial salinity levels (LW: lower salinity wetlands; HW: higher salinity wetlands) in the Yellow River Delta, China. Results showed that, in no salt addition treatments, the cumulative N2O emissions were linearly related to nitrogen addition, and high nitrogen addition significantly promoted N2O emissions by 213% in LW soils and 848% in HW soils (p < 0.05), indicating that the mitigate effects of nitrogen addition to the deleterious salt stress were stronger in HW soils. Meanwhile, the promoting effects of DN and KN treatments were more obvious than NH treatments, suggesting that denitrification was responsible for the N2O emission. However, with salt addition, the nonlinear response pattern and reduced response sizes were observed for KN and DN treatments (p < 0.05), suggesting the alteration in responses of N2O emission to nitrogen addition by salt stress. In addition, the reduction and modification of response pattern was more obvious in soil with lower initial salinity. The findings of this work suggest the uniqueness and complexity of N2O emission responses to nitrogen inputs related to the salinity levels in coastal wetlands.

9.
Quant Imaging Med Surg ; 10(7): 1515-1525, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32676369

RESUMO

Background: This study aimed to evaluate the effectiveness of spectral computed tomography (CT) mono-energy imaging combined with metal artifact reduction software (MARs) for metal implant artifact reduction using a phantom. Methods: A quantitative standard phantom with 9 cylinders was used to simulate the attenuation of the different tissues of the human body around the metal implant. Groups A and B were divided according to conventional CT scan mode and spectral CT scan mode. Three sets of reconstructed images, including 120 kVp-like + MARs images, mono-energy images (MonoE), and MonoE + MARs images, were generated after spectral CT scanning. High-attenuation artifacts and low-attenuation artifacts were observed around the coil in the images of groups A and B. The CT values (Hounsfield unit) and standard deviation (SD) values of the artifacts were measured, and the artifact index and hardening artifact removal rate were calculated. Results: Compared to conventional poly-energy CT images, for high-attenuation and low-attenuation artifacts, the artifact indices of 120 kVp-like + MARs, MonoE, and MonoE + MARs images were all reduced significantly. The hardening artifact removal rates of the high-attenuation and low-attenuation artifacts of 120 kVp-like + MARs images were 82% and 92%, respectively. The hardening artifact removal rate of the high-attenuation and low-attenuation artifacts of MonoE and MonoE + MARs images increased with the mono-energy level. Conclusions: Spectral CT using the 120 kVp-like + MARs, 110-140 keV MonoE, and MonoE + MARs reconstruction methods can reduce metal implant artifacts in varying degrees. MonoE + MARs reconstruction was the best method for reducing metal artifacts.

10.
ACS Appl Mater Interfaces ; 12(26): 29876-29882, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492328

RESUMO

Recently, Pickering emulsion stabilized by Janus particles has received considerable attention for interfacial reactions and droplet manipulation. However, its potential interests have been rarely explored because of the difficulties in designing and fabricating Janus particles for Pickering emulsion with suitable applications. Also, photocatalytic materials are scarcely applied as emulsifiers in Pickering emulsions because of their photogenerated hydrophilicity. This work reports the synthesis of methyl-capped Janus TiO2-SiO2 particles (MJTSs), which can be used as a novel emulsifier and photocatalyst simultaneously. The MJTSs, composed of an anatase TiO2 sphere and silica rod, are prepared by inverse emulsion-based step-by-step growth. We demonstrate that the Pickering emulsion stabilized by MJTSs represents extraordinary ability of emulsification, excellent stability, and tunable emulsion type (water in oil or oil in water). In addition, the MJTSs exhibit photocatalytic activity in decomposition of pollutants in the water phase while maintaining the stability of the Pickering emulsion.

11.
Chem Commun (Camb) ; 56(36): 4954-4957, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32239069

RESUMO

The noncovalent structural locking of thermoresponsive polyion complex micelles, nanowires, and vesicles can be implemented via hydrogen bonding assisted polyion complexation through polymerization-induced electrostatic self-assembly (PIESA) using an arginine-like cationic monomer.

12.
Nat Struct Mol Biol ; 27(4): 382-391, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32251414

RESUMO

The bestrophin family of calcium (Ca2+)-activated chloride (Cl-) channels, which mediate the influx and efflux of monovalent anions in response to the levels of intracellular Ca2+, comprises four members in mammals (bestrophin 1-4). Here we report cryo-EM structures of bovine bestrophin-2 (bBest2) bound and unbound by Ca2+ at 2.4- and 2.2-Å resolution, respectively. The bBest2 structure highlights four previously underappreciated pore-lining residues specifically conserved in Best2 but not in Best1, illustrating the differences between these paralogs. Structure-inspired electrophysiological analysis reveals that, although the channel is sensitive to Ca2+, it has substantial Ca2+-independent activity for Cl-, reflecting the opening at the cytoplasmic restriction of the ion conducting pathway even when Ca2+ is absent. Moreover, the ion selectivity of bBest2 is controlled by multiple residues, including those involved in gating.


Assuntos
Bestrofinas/ultraestrutura , Canais de Cloreto/ultraestrutura , Conformação Proteica , Animais , Bestrofinas/química , Bestrofinas/genética , Cálcio/química , Bovinos , Canais de Cloreto/química , Canais de Cloreto/genética , Microscopia Crioeletrônica , Citoplasma/química , Citoplasma/genética , Citoplasma/ultraestrutura , Humanos , Ativação do Canal Iônico/genética , Ligação Proteica/genética , Transdução de Sinais
13.
Cancer Med ; 9(9): 3057-3069, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32150664

RESUMO

BACKGROUND: Alpha-fetoprotein (AFP), routinely used for diagnosis of hepatocellular carcinoma (HCC), is limited with relatively low sensitivity and high false positivity in HBV-related HCC (HBV-HCC). Thus, an alternative approach was explored to improve specificity/sensitivity for diagnosis of HBV-HCC, using the combination of AFP, inflammatory score, and liver function. METHODS: Chronic hepatitis B (CHB) (n = 510) and HBV-HCC (n = 473) patients were identified retrospectively for this study. The diagnostic value of single vs combined biomarkers for HBV-HCC was analyzed, using ROC curve. RESULTS: It was observed that elderliness, male sex, cirrhosis, HBeAg+ or no-antiviral therapy, and elevation of ALT, AST, neutrophil-lymphocyte ratio (NLR), and AFP were associated with developing HBV-HCC. However, the cut-off ALT defined by Chinese standard, but not by AASLD, was a risk factor. Interestingly, AFP of HBeAg- HBV-HCC patients without cirrhosis was significantly higher than that of the HBeAg+ patients. AUC values for AFP, ALT, AST, or NLR were 0.84 (95% CI: 0.815-0.862), 0.533 (95% CI: 0.501-0.565), 0.696 (95% CI: 0.666-0.725), or 0.684 (95% CI: 0.654-0.713) with optimal cut-off at 7.21 ng/mL, 43 IU/mL, 38 IU/mL, or 2.61, respectively. Combination of AFP with ALT, AST, and NLR improved the diagnostic performance for HBV-HCC, compared to any of the single biomarkers or any other combinations among these patients (except no-cirrhosis). CONCLUSIONS: Elderliness, male sex, elevated ALT, AST, NLR, AFP, cirrhosis, HBeAg+ , and no-antiviral treatment were independent risk factors for HBV-HCC. AASLD standard of ALT cut-off value may not be suitable for the Chinese population. Regular monitoring of HCC among HBeAg- patients with abnormal AFP may improve the management of HBV-HCC. The diagnostic performance of AFP combined with ALT, AST, and NLR for HBV-HCC was superior to single biomarker or any other combinations among these patients, and its diagnostic equation can be used as useful tool for differentiation of HBV-HCC from CHB.

14.
Kidney Int ; 97(4): 765-777, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32061436

RESUMO

Renal accumulation and exposure of cadmium originating from pollution in agricultural land and the prevalence of cigarette smoking remains an unneglectable human health concern. Whereas cadmium exposure has been correlated with increased incidence of a variety of kidney diseases, little is known pertaining to its effect on renal drug disposition and response in patients. Here, we report that cadmium exposure significantly increased the activity of organic cation transporter 2 (OCT2), a critical renal drug transporter recommended in United States Federal Drug Administration guidance for assessment during drug development. Cadmium enhanced OCT2 trafficking to the cell membrane both in vitro and in vivo. Mechanistically cadmium-mediated OCT2 translocation was found to involve protein-protein interaction between serine/threonine-protein kinase AKT2, calcium/calmodulin and the AKT substrate AS160 in in vitro cellular studies. The formed protein complex could selectively facilitate phosphorylation of AKT2 at T309, which induced translocation of OCT2 to the plasma membrane. Moreover, cadmium exposure markedly exacerbated nephrotoxicity induced by cisplatin, an OCT2 substrate, by increasing its accumulation in the mouse kidney. Consistently, there was a significant correlation between plasma cadmium level and alteration of renal function in cervical cancer patients who underwent chemotherapy with cisplatin. Thus, our studies suggest that membrane transporter distribution induced by cadmium exposure is a previously unrecognized factor for the broad variation in renal drug disposition and response.

15.
Int J Biol Macromol ; 146: 497-507, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923489

RESUMO

Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a predominant DNA sensor inducing the activation of the innate immune responses that produce proinflammatory cytokines and type I interferons, which has been well-investigated in mammals. However, chicken cGAS (chcGAS), which participates in avian innate immunity, has not been well-investigated. Here, we cloned the complete open reading frame sequence of chcGAS. Multiple sequence alignment and phylogenetic analysis revealed that chcGAS was homologous to mammalian cGAS. The chcGAS mRNA was highly expressed in the bone marrow and ileum. The subcellular localization of chcGAS was mainly in the cytoplasm, and partial co-localization was observed in the endoplasmic reticulum. Through overexpression and RNA interference, we demonstrated that chcGAS responded to exogenous dsDNA, HS-DNA, and poly(dA:dT), and to self dsDNA from the DNA damage response, thereby triggering the activation of STING/TBK1/IRF7-mediated innate immunity in both chicken embryonic fibroblasts and chicken liver cancer cells. Furthermore, downregulation of chcGAS enhanced the infection of fowl adenovirus serotype 4 in LMH cells. Our results demonstrated that chcGAS was an important cytosolic DNA sensor activating innate immune responses and may shed light on a strategy for preventing infectious diseases in the poultry industry.


Assuntos
Adenoviridae/imunologia , Galinhas/imunologia , Galinhas/virologia , Citosol/metabolismo , DNA/metabolismo , Imunidade Inata , Nucleotídeos Cíclicos/metabolismo , Sorogrupo , Sequência de Aminoácidos , Animais , Linhagem Celular , Dano ao DNA , Etoposídeo/farmacologia , Perfilação da Expressão Gênica , Fator Regulador 7 de Interferon/metabolismo , Interferon beta/metabolismo , Interleucina-1beta/metabolismo , Nucleotídeos Cíclicos/química , Filogenia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Transdução de Sinais/efeitos dos fármacos , Frações Subcelulares/metabolismo
16.
J Am Chem Soc ; 142(3): 1341-1347, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31893500

RESUMO

Active oxygen species (AOS) play key roles in many important catalytic reactions relevant to clean energy and environment. However, it remains challenging to characterize the active sites for producing AOS and to image the surface properties of AOS, especially on multicomponent metallic catalyst surfaces. Herein, we utilize tip-enhanced Raman spectroscopy (TERS) to probe the local generation and diffusion of OH radicals on a Pd/Au(111) bimetallic catalyst surface. The reactive OH radicals can be catalytically generated from hydrogen peroxide (H2O2) at the metal surface, which then oxidizes the surface adsorbed thiolate, a reactant that is used as the TERS probe. By TERS imaging of the spatial distribution of unreacted thiolate molecules, we demonstrate that the Pd surface is active for generation of OH radicals and the Pd step edge shows much higher activity than the Pd terrace, whereas the Au surface is inactive. Furthermore, we find that the locally generated OH radicals at the Pd step edge could diffuse to both the Au and the Pd surface sites to induce oxidative reactions, with a diffusion length estimated to be about 5.4 nm. Our TERS imaging with few-nanometer spatial resolution not only unravels the active sites but also characterizes in real space the diffusion behavior of OH radicals. The results are highly valuable to understand AOS-triggered catalytic reactions. The strategy of using reactants with large Raman cross sections as TERS probes may broaden the application of TERS for studying catalysis with reactive small molecules.

17.
Microb Ecol ; 79(3): 644-661, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31444524

RESUMO

As an exotic plant species, Spartina alterniflora seriously threatens native ecosystem function in Chinese coastal regions. Unveiling the dynamics of soil bacteria community during its invasion is essential for a better understanding of related biogeochemical processes, while the shift in soil bacterial community over invasive time remains unclear. A short-term chronosequence was identified to assess the impacts of Spartina alterniflora invasion on soil nutrients and bacterial community composition and structure (using 16S rRNA gene high-throughput sequencing) over the time of invasion (i.e., (1) at least 10 years, (2) nearly 5 years, (3) less than 2 years, and (4) in native salt marshes or 0 years) in the Yellow River Estuary. The results exhibited an orderly change in the soil physicochemical properties and bacterial community composition over the invasion time. Soil pH showed a significant decrease with the accumulation of soil organic matter (SOM), whereas soil nutrients such as soil dissolved organic carbon (DOC), total nitrogen (TN), nitrate (NO3-), ammonium (NH4+), K+, and Mg2+ were generally increased with the age of the invasion. The number of operational taxonomic units (OTUs, 97% similarity level) exhibited a decreasing trend, which suggested a decline in bacterial diversity with the invasion age. The dominant groups at the phylum level were Proteobacteria, Bacteroidetes, Chloroflexi, Acidobacteria, and Gemmatimonadetes (the sum of relative abundance was > 70% across all samples). The relative abundances of Chloroflexi and Gemmatimonadetes steadily decreased, while the abundance of Bacteroidetes significantly increased with the plant invasion. The distribution pattern of the soil bacteria was clearly separated according to the principal coordinate analysis (PCoA) and canonical correspondence analysis (CCA) in native and invaded salt marshes. The variation in the soil bacterial community was tightly associated with the soil physicochemical properties (Mantel test, P < 0.05). Variance partitioning analysis (VPA) showed that plant traits explained 4.95% of the bacterial community variation, and soil variables explained approximately 26.96% of the variation. Network analysis also revealed that plant invasion strengthens the interaction among soil bacterial communities. Overall, our findings highlight the bacterial community succession during the Spartina alterniflora invasion in coastal salt marsh soils, which can provide insight regarding the association between soil development and invasive plant.


Assuntos
Microbiota , Poaceae/crescimento & desenvolvimento , Microbiologia do Solo , Fenômenos Fisiológicos Bacterianos , China , Estuários , Espécies Introduzidas , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
18.
Water Environ Res ; 92(4): 579-587, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31560133

RESUMO

In this study, the inline coagulation was combined with ultrafiltration and nanofiltration (UF-NF) in a pilot study for Tai Lake water treatment. The results showed that the combination process was very effective for Tai Lake water treatment in terms of organic removal and membrane fouling control. With inline coagulation, no irreversible membrane fouling was observed for either UF or NF at fluxes of 65-90 and 22-26 L/(m2  hr), respectively. The membrane foulants were analyzed, and the results indicated that the low molecular weight fractions in the feed were main membrane fouling contributors for both UF and NF, where hydrophilic substances and proteins, as well as neutral substances and humic acids with polycarboxyl groups, contributed significantly to UF and NF membrane fouling, respectively. Compared with direct UF-NF filtration without coagulation, the coagulants could aggregate organic micromolecules for cake formation. With inline coagulation, the moving flocs could generate shear stress to scrub the membrane surface for fouling control of UF. Moreover, with inline coagulation, the organics removal efficiency could be further increased by 10%-20%. With NF, the permeate had a TOC concentration of less than 0.5 mg/L, satisfying the drinking water quality. Therefore, the coagulation-UF-NF is very useful for Tai Lake water treatment. PRACTITIONER POINTS: Inline coagulation-UF-NF for Tai Lake Water treatment is implemented. Inline coagulation can aggregate hydrophilic substances to reduce membrane fouling. Moving flocs produce shear stress for fouling control of UF-NF. Superior quality of permeate is achieved with the combined coagulation-UF-NF process.


Assuntos
Ultrafiltração , Purificação da Água , Substâncias Húmicas , Lagos , Membranas Artificiais , Projetos Piloto
19.
J Trace Elem Med Biol ; 57: 68-74, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31568922

RESUMO

BACKGROUND AND AIM: Major and trace elements play an important role in human body, and it has been reported that ionomic distribution differ greatly in tumor patients. The aim of the present study was to investigate the effects of cisplatin-based neoadjuvant chemoradiotherapy on the ionomic profile in human plasma as a potential biomarker for the therapeutic effects of cervical cancer. METHOD: Thirty-seven patients with cervical cancer receiving neoadjuvant chemoradiotherapy were included in this study, pretherapy and post-treatment blood samples were collected and concentrations of 24 ions were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: The results showed that after cisplatin chemotherapy and radiotherapy, patients' plasma Pt level significantly increased, Na, Mg, P, K, Ca, Se, Cu, Zn, Se, Sr, Ba levels significantly decreased (P < 0.01), and Al, Cu ions were significantly correlated with the treatment effect (P < 0.05). In addition, the pattern of elemental correlations changed dramatically after the neoadjuvant chemoradiotherapy. CONCLUSION: The results indicated that the plasma ionomic profile may serve as a quick and convenient tool to reflect the therapeutic effect of cisplatin-based chemoradiotherapy in cervical cancer patients, and supplement of certain essential elements may be of great importance for the maintenance of ion homeostasis in human body and for the reduction of adverse effect of chemotherapy and radiotherapy.


Assuntos
Íons/sangue , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/diagnóstico , Quimiorradioterapia , Feminino , Humanos , Espectrometria de Massas , Terapia Neoadjuvante , Oligoelementos/sangue , Neoplasias do Colo do Útero/tratamento farmacológico
20.
Acad Radiol ; 27(2): 219-226, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31076330

RESUMO

RATIONALE AND OBJECTIVES: Lymphangiomatosis is a rare disease characterized by the widespread presence of lymphangiomas in any part of the body. In previous studies, lymphatic vessel abnormalities in lymphangiomatosis have only rarely been mentioned. The objective of this paper is to discuss the imaging features of lymphangiomatosis, including cystic lesions and lymphatic abnormalities, on computed tomography lymphangiography (CTL). MATERIALS AND METHODS: All 34 patients who were diagnosed with lymphangiomatosis underwent direct lymphangiography followed by CTL. The CTL images were independently analyzed by two experienced radiologists. The CTL image analyses included assessment of the features of cystic lesions and lymphatic vessel abnormalities. RESULTS: (i) CTL revealed several cystic lesions ranging in size from 3 mm to 14 cm; the lesions were located in the neck and shoulders (61.8%), mediastinum (52.9%), retroperitoneum (70.6%), and pelvis and perineum (64.7%). (ii) Approximately 29.4% of patients showed abnormal contrast medium accumulation in cystic masses. (iii) Approximately 67.6% of patients showed lymphatic reflux. (iv) Dilated lymphatic vessels were distributed in the mediastinum (38.2%), retroperitoneum (50.0%), pelvis and lower limbs (47.1%). (v) Finally, 8.8% of patients had perineal lymphatic fistulae, and 2.9% of patients had chyluria. CONCLUSION: Lymphangiomatosis is a type of systemic lymphatic abnormality that is accompanied by multiple cystic lesions. The therapeutic measures for lymphangiomatosis are determined by the size of the cystic lesions. Furthermore, the prognosis of lymphangiomatosis is affected by lymphatic abnormalities.


Assuntos
Linfangioma , Linfografia , Meios de Contraste , Humanos , Linfangioma/diagnóstico por imagem , Pelve , Tomografia Computadorizada por Raios X
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