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1.
Water Sci Technol ; 83(4): 841-853, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33617491

RESUMO

The promising synergistic electrocatalytic system of phosphate (PO43-) with the mediator cobalt(II) (for short E-Co(II)-PO43-) was employed to degrade cationic dye methylene blue (MB). The exploration in the electrocatalytic process revealed that the main intermediate active oxidation products were Co(III), accompanied with hydroxyl radicals and peroxodiphosphates (P2O84-). Their synergistic electrocatalytic degradation rate to MB and total organic carbon (TOC) was up to 100 and 60% in 40 min, respectively, which was 5 times and 2.6 times that in a direct electrocatalytic system, correspondingly. The degradation process of the E-Co(II)-PO43- system on MB started with the bond being broken at the N-C junction of the MB molecule and intermediate active oxidation substances being generated, such as phenothiazine, 2-amino-5-(N-methylformamide) benzene sulfonic acid and N1,N1-dimethyl-1,4 diaminobenzene. Then, the intermediates were degraded into aniline, phenol and benzene sulfonic acid, and eventually decomposed into inorganic substances like CO2 and water. The electrocatalytic degradation mechanism of E-Co(II)-PO43- system on MB was the combination of indirect oxidation of the intermediate oxidants like Co(III), P2O84- and the hydroxyl radical with direct electrocatalysis on the platinum titanium electrode, where the electrocatalytic oxidation of Co(III) was dominant.

2.
Biomed Chromatogr ; : e5095, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607700

RESUMO

A sensitive and robust method has been developed using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) assay to quantify Tat-K13, a novel interfering peptide for the treatment of ischemic stroke, in human plasma. Automated solid-phase extraction (SPE) on Waters Oasis WCX (30 µm, 10 mg) 96-well plate was used to extract Tat-K13 from human plasma and the extracts were separated on a Waters Acquity CSH column (2.1×50 mm i.d., 1.7 µm) with a gradient elution method by mobile phase of A (nonafluoropentanoic acid-acetic acid-water (1:2:1000, v/v/v)) and B (nonafluoropentanoic acid-acetic acid-water-acetonitrile (1:2:100:900, v/v/v/v)). The method was fully validated following international bioanalytical guidelines and showed good linearity from 2.10 to 1050 ng/mL. The method was successfully applied to investigate the clinical pharmacokinetics of Tat-K13 in health volunteers. Rapid elimination of Tat-K13 from the body was observed, T1/2 ranging from 0.26 to 0.78 h across different dose levels. The exposure of Tat-K13 was approximate dose-dependent in terms of AUC0-∞ and Cmax .

3.
Ther Drug Monit ; 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33587427

RESUMO

BACKGROUND: The determination of antiretroviral drugs in hair is receiving considerable research interest to assess long-term adherence to antiretroviral therapy (ART). Currently in China, lamivudine, zidovudine, nevirapine, efavirenz, ritonavir, and lopinavir are combined as first- and second-line free therapy regimens and are recommended for people living with human immunodeficiency virus (HIV) (PLWH). Simultaneous determination of the six antiretroviral drugs in human hair is important for accurately and widely assessing long-term adherence in Chinese PLWH receiving different ART regimens. METHODS: Six drugs were extracted from 10-mg hair samples incubated in methanol for 16 h at 37 °C and then analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) using a mobile phase of 95% methanol, with an electrospray ionization (ESI) source in multiple reaction monitoring and positive mode. RESULTS: The LC-ESI+-MS/MS method exhibited a linear range (R2 > 0.99) within 6-5000, 10-5000, 6-50000, 12-50000, 8-5000, and 8-12500 pg/mg for lamivudine, zidovudine, nevirapine, efavirenz, ritonavir, and lopinavir. For all six drugs, the limits of quantification ranged between 6 and 12 pg/mg. The intra-day and inter-day coefficients of variation were within 15%, and the recoveries ranged from 91.1% to 113.7%. Furthermore, the other validation parameters (i.e., selectivity, matrix effect, stability, and carryover) met the acceptance criteria stipulated by guidelines of the United States Food and Drug Administration and European Medicines Agency. Significant intergroup differences were observed between high- and low-adherence groups, with high inter-correlations in the hair content of the six drugs. CONCLUSIONS: The developed method demonstrated good reliability, to comprehensively and accurately assess adherence in PLWH receiving different ART regimens.

4.
PLoS One ; 16(2): e0232918, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33600466

RESUMO

To determine the expression profile and clinical significance of long non-coding RNAs (lncRNAs) in peripheral blood mononuclear cells (PBMCs) of patients with primary gout and healthy control subjects. Human lncRNA microarrays were used to identify the differentially expressed lncRNAs and mRNAs in primary gout patients (n = 6) and healthy control subjects (n = 6). Bioinformatics analyses were performed to predict the roles of differently expressed lncRNAs and mRNAs. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression levels of 8 lnRNAs in 64 primary gout patients and 32 healthy control subjects. Spearman's correlation was used to analyze the correlation between these eight lncRNAs and the laboratory values of gout patients. A receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic value of the lncRNAs identified in gout. The microarray analysis identified 1479 differentially expressed lncRNAs (879 more highly expressed and 600 more lowly expressed), 862 differentially expressed mRNAs (390 more highly expressed and 472 more lowly expressed) in primary gout (fold change > 2, P < 0.05), respectively. The bioinformatic analysis indicated that the differentially expressed lncRNAs regulated the abnormally expressed mRNAs, which were involved in the pathogenesis of gout through several different pathways. The expression levels of TCONS_00004393 and ENST00000566457 were significantly increased in the acute gout flare group than those in the intercritical gout group or healthy subjects (P<0.01). Moreover, inflammation indicators were positive correlated with TCONS_00004393 and ENST00000566457 expression levels. The areas under the ROC curve of ENST00000566457 and NR-026756 were 0.868 and 0.948, respectively. Our results provide novel insight into the mechanisms of primary gout, and reveal that TCONS_00004393 and ENST00000566457 might be as candidate targets for the treatment of gout flare; ENST00000566457 and NR-026756 could effectively discriminate between the gout and the healthy control groups.

5.
J Am Geriatr Soc ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33533055

RESUMO

OBJECTIVES: To determine the effects of baseline and changes in frailty states on subsequent depressive symptoms, and whether sleep duration would modify these effects. DESIGN: Prospective, cohort study. SETTING: The 2011 baseline and 2013 follow-up waves of the China Health and Retirement Longitudinal Study (CHARLS). PARTICIPANTS: Community-dwelling old adults who were aged 60 or above at baseline and participated in the 2011 and 2013 waves of the CHARLS (N = 5,026). MEASUREMENTS: Frailty was measured using the physical frailty phenotype (PFP) scale. Levels of depressive symptoms were measured by the 10-item Center for Epidemiologic Studies Depression Scale (CES-D). Using the generalized estimating equations (GEE), the effects of baseline and transitions in frailty states were examined on subsequent depressive symptoms, adjusting for a range of confounding variables. RESULTS: Baseline prefrail (b = 0.97, P < .05) and frail states (b = 0.35, P < .05) were associated with higher subsequent level of depressive symptoms 2 years later. Within individuals who were robust at baseline, transitioning into prefrail/frail (b = 3.04, P < .001) was associated with a higher subsequent level of depressive symptoms, and this association was accelerated by short sleep duration. Within individuals who were prefrail at baseline, transitioning into frail (b = 1.76, P < .001) was associated with higher subsequent levels of depressive symptoms, and this association was stronger among those who reported short sleep duration. CONCLUSION: Baseline and transitions in frailty states were significantly related with higher subsequent levels of subsequent depressive symptoms. Short sleep duration significantly moderated the effects of baseline or transitions of frailty on subsequent depressive symptoms. Targeted interventions could be implemented to improve sleep quality for prefrail and frail older adults.

6.
J Colloid Interface Sci ; 590: 632-640, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582365

RESUMO

The directional synthesis of transition metal phosphides was considered to be an effective strategy to solve the overdependence of noble metals on photocatalytic hydrogen evolution (PHE) reactions. Inspiringly, this work reported a facile method for constructing hollow Co2P nanocages (Co2P NCGs) that derived from ZIF-67 by calcining and phosphiding procedure in nitrogen atmosphere to act as non-noble metal cocatalysts. Followed with further coating thin-layered ZnIn2S4 (ZIS) on the surface of Co2P NCGs through a hydrothermal reaction, the hierarchical robust Co2P/ZnIn2S4 nanocages (Co2P/ZIS NCGs) were then delicately fabricated as efficient photocatalysts for PHE reactions. The uniquely hollow structure of Co2P NCGs largely diffused the photogenerated chargers that induced from ZIS and the closely interfacial contact significantly promoted the separation and transfer of electrons from ZIS to Co2P according to density functional theory (DFT) calculation, synergistically resulting in an efficient hydrogen generation performance. PHE results showed that an efficient H2 evolution rate of 7.93 mmol/g/h over 10% Co2P/ZIS NCGs was achieved, about 10 times higher than that of pristine ZnIn2S4. More importantly, the hierarchically hollow Co2P/ZIS NCGs exhibited ascendant PHE activity in comparison with that of 1% noble metal (Pt, Au, Ag) loaded ZnIn2S4 with superior sustainability, all indicating the efficient and stable photocatalysts of Co2P/ZIS NCGs for PHE reactions.

7.
J Hematol Oncol ; 14(1): 19, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472669

RESUMO

BACKGROUND: TNBC is the most aggressive breast cancer with higher recurrence and mortality rate than other types of breast cancer. There is an urgent need for identification of therapeutic agents with unique mode of action for overcoming current challenges in TNBC treatment. METHODS: Different inhibitors were used to study the cell death manner of DMOCPTL. RNA silencing was used to evaluate the functions of GPX4 in ferroptosis and apoptosis of TNBC cells and functions of EGR1 in apoptosis. Immunohistochemical assay of tissue microarray were used for investigating correlation of GPX4 and EGR1 with TNBC. Computer-aided docking and small molecule probe were used for study the binding of DMOCPTL with GPX4. RESULTS: DMOCPTL, a derivative of natural product parthenolide, exhibited about 15-fold improvement comparing to that of the parent compound PTL for TNBC cells. The cell death manner assay showed that the anti-TNBC effect of DMOCPTL mainly by inducing ferroptosis and apoptosis through ubiquitination of GPX4. The probe of DMOCPTL assay indicated that DMOCPTL induced GPX4 ubiquitination by directly binding to GPX4 protein. To the best of our knowledge, this is the first report of inducing ferroptosis through ubiquitination of GPX4. Moreover, the mechanism of GPX4 regulation of apoptosis is still obscure. Here, we firstly reveal that GPX4 regulated mitochondria-mediated apoptosis through regulation of EGR1 in TNBC cells. Compound 13, the prodrug of DMOCPTL, effectively inhibited the growth of breast tumor and prolonged the lifespan of mice in vivo, and no obvious toxicity was observed. CONCLUSIONS: These findings firstly revealed novel manner to induce ferroptosis through ubiquitination of GPX4 and provided mechanism for GPX4 inducing mitochondria-mediated apoptosis through up-regulation of EGR1 in TNBC cells. Moreover, compound 13 deserves further studies as a lead compound with novel mode of action for ultimate discovery of effective anti-TNBC drug.

8.
Phytother Res ; 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452698

RESUMO

The present study was undertaken to identify whether prostaglandin E2 receptor is the potential receptor/binding site for Ginkgolide A, Ginkgolide B, Ginkgolide K, and Bilobalide, the four main ingredients of the Ginkgo biloba L., leaves. Using functional assays, we identified EP4, coupled with Gs protein, as a target of Ginkgolide B. In human neuroblastoma SH-SY5Y cells suffered from oxygen-glucose deprivation/reperfusion, Ginkgolide B-activated PKA, Akt, and ERK1/2 as well as Src-mediated transactivation of epidermal growth factor receptor. These resulted in downstream signaling pathways, which enhanced cell survival and inhibited apoptosis. Knockdown of EP4 prevented Ginkgolide B-mediated Src, epidermal growth factor receptor (EGFR), Akt, and ERK1/2 phosphorylation and neuroprotective effects. Moreover, Src inhibitor prevented Ginkgolide B-mediated EGFR transactivation and the downstream Akt and ERK1/2 activation, while the phosphorylation of PKA induced by Ginkgolide B was not affected, indicating Ginkgolide B might transactivate EGFR in a ligand-independent manner. EP4 knockdown in a rat middle cerebral artery occlusion (MCAO) model prevented Ginkgolide B-mediated infarct size reduction and neurological assessment improvement. At the same time, the increased expressions of p-Akt, p-ERK1/2, p-PKA, p-Src, and p-EGFR and the deceased expression of cleaved capases-3 induced by Ginkgolide B in cerebral cortex were blocked due to EP4 knockdown. In conclusion, Ginkgolide B exerts neuroprotective effects in rat MCAO model through the activation of EP4 and the downstream transactivation of EGFR.

9.
Sci Total Environ ; 770: 145302, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33515894

RESUMO

Paddy soil contaminated by cadmium (Cd) has attracted worldwide attention, while foliar spraying of zinc (Zn) could be considered a cost-effective and practical agronomic measure for reducing Cd accumulation in rice grain. However, the effects due to foliar spraying of Zn on different cultivars, as well as the mechanism of subsequent processes taking place are not fully understood up to now. To go a step ahead, a field experiment was conducted with the aim of studying the capability of foliar application of Zn (0.4% ZnSO4) to reduce Cd concentration in grain in five late rice cultivars (here named JLYHZ, FYY272, JY284, CLY7 and LXY130), and the antioxidant activities and subcellular distribution of Cd in the leaves. The results indicate that foliar Zn application significantly decreased grain yield in JY284, CLY7 and JLYHZ, compared to controls. In addition, foliar application of Zn significantly decreased Cd concentration in grain of the five rice cultivars, while increased Zn concentration. The effect of foliar application of Zn on transport coefficients of Cd varied greatly for the different rice cultivars. Foliar application of Zn significantly decreased the malondialdehyde (MDA) concentration in rice leaves, and increased peroxidase (POD) activity. Also, it changed the distribution of Cd in the soluble fraction in leaves (expressed as proportion), which was significantly decreased, and the proportion of Cd in the cell wall increased. The structural equation model (SEM) revealed the positive effects of flag leaf Cd, first node Cd, old leaf Cd, and root Cd concentration on grain Cd concentration. Flag leaf Cd had the highest standardized total effects on grain Cd concentration, followed by old leaf Cd. These results indicated that foliar application of Zn was effective in reducing grain Cd concentration of late rice by enhancing antioxidant activities and Cd chelation onto cell wall of leaves, and reducing Cd concentrations in leaves.

10.
Artigo em Chinês | MEDLINE | ID: mdl-33478196

RESUMO

BACKGROUND: Targeted therapy for patients with driver genes positive and immunotherapy for patients with driver gene-negative but high programmed death-ligand 1 (PD-L1) expression are the standards of first-line treatment for patients with advanced non-small cell lung cancer. The treatment options for patients with driver gene positive and high PD-L1 expression are still worth exploring. METHODS: The characteristics of 315 patients with non-small lung cancer were identified to analyze the clinicopathological characteristics of patients with driver gene positive and high PD-L1 expression, and the efficacy of targeted therapy. RESULTS: Among the 315 patients, the total positive rate of driver genes was 62.2%, and the high PD-L1 expression rate (≥50%) was 11.2%. The proportion of patients with driver gene positive and high PD-L1 expression was 10.7%. PD-L1 was highly expressed in patients with epidermal growth factor receptor (EGFR) mutation, KRAS mutation, ALK fusion, BRAF mutation, and MET 14 exon skip mutation, the proportions were 7.8% (11/141), 18.2% (4/22), and 23.1%, (3/13), 50.0% (2/4) and 100% (1/1) respectively. EGFR mutation positive with PD-L1 high expression was mainly in patients with stage IV lung adenocarcinoma. KRAS mutation positive with PD-L1 high expression was mainly in patients with a history of smoking. Among them, two patients were followed in detail for targeted therapy, who with ALK fusion-positive and PD-L1 high expression (90%), EGFR L858R mutation and PD-L1 high expression (70%) respectively. The total OS of the patients was 5 months, 2 months. CONCLUSIONS: The high PD-L1 expression rate in NSCLC patients with different driver gene mutations was variable, which maybe correlated with distinct clinicopathological characteristics. Patients with sensitive mutations and high PD-L1 expression may be less benefit from targeted therapy and have poor prognosis.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33462074

RESUMO

INTRODUCTION: Respective alterations in resting-state brain neural activity and cerebral blood flow (CBF) in type 2 diabetes mellitus (T2DM) have been reported. However, their coupling alteration in T2DM remains largely unknown. RESEARCH DESIGN AND METHODS: Twenty-seven patients with T2DM aged 40-67 years and 36 well-matched healthy controls (HCs) underwent resting-state functional MRI (rs-fMRI) and arterial spin labeling (ASL) scans at two time points with a 5-year interval. Regional homogeneity (ReHo) and CBF were calculated from rs-fMRI and ASL, respectively. The standardized ReHo:CBF ratio (mReHo:mCBF ratio), the spontaneous neuronal activity per unit CBF supply, was compared between the two time points. Relationships between the mReHo:mCBF ratio and memory performance were analyzed. RESULTS: Over 5 years, decreased mReHo:mCBF ratios in patients with T2DM were mainly distributed in four regions, among which the left insula exhibited more severely decreased mReHo:mCBF ratio in patients with T2DM than in HCs, while the left postcentral gyrus, the right Rolandic operculum, and the right precentral gyrus showed no significant intergroup difference. Correlations between the mReHo:mCBF ratio and memory performance were also found in patients with T2DM. CONCLUSIONS: This study suggests that T2DM may accelerate neurovascular coupling impairment in specific brain regions (the left insula), contributing to memory decline. This study implies that the mReHo:mCBF ratio is a potential imaging marker for detecting neurovascular changes.

12.
Nano Lett ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33404256

RESUMO

Thermoelectric (TE) technology provides a new way to directly harvest and convert the heat continuously released from the human body. The greatest challenge for TE materials applied in wearable TE generators is compatible with the constantly changing morphology of the human body while offering a continuous and stable power output. Here, a stretchable carboxylic single-walled carbon nanotube (SWNT)-based TE fiber is prepared by an improved wet-spinning method. The stable Seebeck coefficient of the annealed carboxylic SWNT-based TE fiber is 44 µV/K even under the tensile strain of ∼30%. Experimental results show that the fiber can continue to generate constant TE potential when it is changed to various shapes. The new stretchable TE fiber has a larger Seebeck coefficient and more stretchability than existing TE fibers based on the Seebeck effect, opening a path to using the technology for a variety of practical applications.

13.
J Gen Virol ; 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33416466

RESUMO

Canine distemper virus (CDV) is the aetiological agent that causes canine distemper (CD). Currently, no antiviral drugs have been approved for CD treatment. A77 1726 is the active metabolite of the anti-rheumatoid arthritis (RA) drug leflunomide. It inhibits the activity of Janus kinases (JAKs) and dihydroorotate dehydrogenase (DHO-DHase), a rate-limiting enzyme in de novo pyrimidine nucleotide synthesis. A77 1726 also inhibits the activity of p70 S6 kinase (S6K1), a serine/threonine kinase that phosphorylates and activates carbamoyl-phosphate synthetase (CAD), a second rate-limiting enzyme in the de novo pathway of pyrimidine nucleotide synthesis. Our present study focuses on the ability of A77 1726 to inhibit CDV replication and its underlying mechanisms. Here we report that A77 1726 decreased the levels of the N and M proteins of CDV and lowered the virus titres in the conditioned media of CDV-infected Vero cells. CDV replication was not inhibited by Ruxolitinib (Rux), a JAK-specific inhibitor, but by brequinar sodium (BQR), a DHO-DHase-specific inhibitor, and PF-4708671, an S6K1-specific inhibitor. Addition of exogenous uridine, which restores intracellular pyrimidine nucleotide levels, blocked the antiviral activity of A77 1726, BQR and PF-4708671. A77 1726 and PF-4708671 inhibited the activity of S6K1 in CDV-infected Vero cells, as evidenced by the decreased levels of CAD and S6 phosphorylation. S6K1 knockdown suppressed CDV replication and enhanced the antiviral activity of A77 1726. These observations collectively suggest that the antiviral activity of A77 1726 against CDV is mediated by targeting pyrimidine nucleotide synthesis via inhibiting DHO-DHase activity and S6K1-mediated CAD activation.

14.
Cell Metab ; 33(2): 424-436.e10, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33308446

RESUMO

Caspase-4 is an intracellular sensor for cytosolic bacterial lipopolysaccharide (LPS) and underlies infection-elicited pyroptosis. It is unclear whether and how caspase-4 detects host-derived factors to trigger pyroptosis. Here we show that mitochondrial permeability transition (MPT) activates caspase-4 by promoting the assembly of a protein complex, which we term the Apaf-1 pyroptosome, for the execution of facilitated pyroptosis. MPT, when induced by bile acids, calcium overload, or an adenine nucleotide translocator 1 (ANT1) activator, triggers assembly of the pyroptosome comprised of Apaf-1 and caspase-4 with a stoichiometry ratio of 7:2. Unlike the direct cleavage of gasdermin D (GSDMD) by caspase-4 upon LPS ligation, caspase-4 activated in the Apaf-1 pyroptosome proceeds to cleave caspase-3 and thereby GSDME to induce pyroptosis. Caspase-4-initiated and GSDME-executed pyroptosis underlies cholestatic liver failure. These findings identify Apaf-1 pyroptosome as a pivotal machinery for cells sensing MPT signals and may shed light on understanding how cells execute intrinsic pyroptosis under sterile conditions.

15.
J Agric Food Chem ; 69(1): 447-458, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33347291

RESUMO

MYB transcription factors (TFs) participate in many biological processes. However, the molecular mechanisms by which MYB TFs affect plant resistance to apple ring rot remain poorly understood. Here, the R2R3-MYB gene MdMYB73 was cloned from "Royal Gala" apples and functionally characterized as a positive regulator of the defense response to Botryosphaeria dothidea. qRT-PCR and GUS staining demonstrated that MdMYB73 was strongly induced in apple fruits and transgenic calli after inoculation with B. dothidea. MdMYB73 overexpression improved resistance to B. dothidea in apple calli and fruits, while MdMYB73 suppression weakened. Increased resistance to B. dothidea was also observed in MdMYB73-expressing Arabidopsis thaliana. Interestingly, salicylic acid (SA) contents and the expression levels of genes related with SA synthesis and signaling were greater in MdMYB73-overexpressing plant materials compared to wild-type controls after inoculation, suggesting that MdMYB73 might enhance resistance to B. dothidea via the SA pathway. Finally, we discovered that MdMYB73 interacts with MdWRKY31, a positive regulator of B. dothidea. Together, MdWRKY31 and MdMYB73 enhanced B. dothidea resistance in apples. Our results clarify the mechanisms by which MdMYB73 improves resistance to B. dothidea and suggest that resistance may be affected by regulating the SA pathway.

16.
Chemosphere ; 263: 128136, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297124

RESUMO

Organic mobilizing agents have been advocated for phytoremediation of heavy metals contaminated soils, while the effects of application period of such agents remain unclear. A pot experiment was conducted, with two composited organic agents (oxalic acid or citric acid + dissolved organic fertilizer (OA + DOF and CA + DOF)) and four application periods (seeding, jointing, flag leaf and heading stages) of sorghum (Sorghum bicolor L.), to investigate their impacts on Cd bioavailability in soil. Results indicated that application of the two composited agents increased soil dissolved organic carbon (DOC) and DTPA extractable Cd by 7.31-49.13%, Cd contents in roots and shoots by 21.49-72.10%, bioaccumulation factor (BCF) and translocation factor (TF) of shoots by 4.44-71.99%, while reduced soil pH by 0.25-0.53 units, respectively. Most of these indices increased with the application periods, and largely peaked with their application during the flag leaf to heading stages. Meanwhile, the maximum sorghum biomass (132.84 g pot-1) and Cd bioaccumulation quantity (BCQ, 0.71 mg pot-1) in shoots were obtained for the CA + DOF applied at the heading. The DTPA extractable Cd was closely related to soil pH and DOC. Similar close relationships were observed between the Cd contents in shoots and soil DTPA extractable Cd, pH and DOC. The BCQ of Cd was positively related to the shoots biomass rather than their Cd contents. Therefore, the sorghum combined with the CA + DOF may be advocated as an alternative phytoremediation mode in Cd-contaminated soils, and the mobilizing agent should be primarily applied at the heading stage.


Assuntos
Poluentes do Solo , Sorghum , Biodegradação Ambiental , Cádmio/análise , Solo , Poluentes do Solo/análise
17.
Bioresour Technol ; 321: 124468, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33296774

RESUMO

The efficient removal of ammonium nitrogen (NH4+-N) is vital to eliminating black and odorous water bodies. In this work, tidal flow constructed wetlands with gravel (TFCW-G) and with a mixture of zeolite and gravel (TFCW-Z) were set up to treat black and odorous water bodies at different hydraulic loading rates (HLRs). Results showed that zeolite significantly enhanced nitrogen removal, and the maximum NH4+-N removal efficiency of 96.69% was achieved in TFCW-Z at HLR of 3 m·d-1 with a flooding and drying cycle of 2 h. Zeolite addition changed the microbial community structure and the abundance of nitrification genes. Comammox Nitrospira was the only enriched strain accounting for NH4+-N removal in TFCW-G, while the co-occurrence of comammox Nitrospira and the canonical and potential ammonia-oxidizing bacteria were identified in TFCW-Z. Summarily, high performance, together with low footprint and low maintenance cost, are characteristics that make the TFCW-Z a promising and competitive alternative.

18.
Molecules ; 25(23)2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33276689

RESUMO

The adherence assessment based on the combination of nevirapine (NVP) and its two metabolites (2-hydroxynevirapine and 3-hydroxynevirapine) would more comprehensively and accurately reflect long-term adherence than that of a single prototype. This study aimed to develop a specific, sensitive and selective method for simultaneous detection of the three compounds in hair and explore whether there was consistency among the three compounds in assessing long-term adherence. Furthermore, 75 HIV-positive patients who were taking the NVP drug were randomly recruited and divided into two groups (high-and low-adherence group). All participants self-reported their days of oral drug administration per month and provided their hair strands closest to the scalp at the region of posterior vertex. The concentrations of three compounds in the hair were determined using a developed LC-MS/MS method in multiple reaction monitoring. This method showed good performances in limit of quantification and accuracy with the recoveries from 85 to 115% and in precision with the intra-day and inter-day coefficients of variation within 15% for the three compounds. The population analysis revealed that patients with high-adherence showed significantly higher concentrations than those with low-adherence for all three compounds. There were significantly moderate correlations of nevirapine with 2-hydroxynevirapine and 3-hydroxynevirapin and high correlation between 2-hydroxynevirapine and 3-hydroxynevirapin. The two NVP's metabolites showed high consistency with NVP in evaluating long-term adherence.

19.
Clin EEG Neurosci ; : 1550059420979250, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33289577

RESUMO

This study examined white matter integrity in patients with left-sided hemifacial spasm (HFS) using diffusion tensor imaging (DTI). Thirty-six patients with left-sided HFS (mean age 53.24 ± 8.16 years) and 36 healthy volunteers (mean age 53.92 ± 7.73 years) were recruited. Tract-based spatial statistics (TBSS) analysis revealed significantly increased fractional anisotropy (FA) of bilateral superior longitudinal fasciculus in HFS patients (P < 0.05, family-wise error corrected), with trends for radial diffusivity to decrease. We inferred that the results may be associated with poor sleep quality, impairment in visuospatial construction, and activity-dependent increases in myelination in HFS patients. Furthermore, the FA value of left superior longitudinal fasciculus showed a positive correlation with HFS duration (r = 0.352, P = .041) and spasm severity (r = 0.416, P = .014). However, the alteration of medial diffusivity and axial diffusivity were not found in bilateral superior longitudinal fasciculus between groups. These findings suggest FA changes of superior longitudinal fasciculus reflected by TBSS analysis may provide valuable insights into the diagnosis of HFS.

20.
Drug Dev Ind Pharm ; : 1-33, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33295808

RESUMO

At present, saccharides as a hydrophilic matrix, have been gradually used in amorphous solid dispersions (ASD) for dispersing poorly water-soluble drugs without surfactants. In this study, an amorphous chitosan oligosaccharide (COS) was applied as a water-soluble matrix to form surfactant-free ASD via the ball milling to vitrify quercetin (QUE) and enhance the dissolution and bioavailability. Solid-state characterization (DSC, XRPD, FTIR, SEM and PLM) and physical stability assessments verified that the prepared ASDs showed excellent physical stability with complete amorphization due to potential interactions between QUE and COS. In vitro sink dissolution tests suggested all QUE-COS ASDs (w:w, 1:1, 1:2 and 1:4) significantly enhanced the dissolution rate of QUE. Meanwhile, in vitro non-sink dissolution exhibited that the maximum supersaturated concentration ranged from 112.62 to 138.00 µg/mL for all QUE-COS ASDs, which was much higher than that of pure QUE. Besides, the supersaturation of QUE-COS ASD kept for at least 24 h. In rat pharmacokinetics, the oral bioavailability of QUE-COS ASDs showed 1.64 ∼ 2.25 times increase compared to the pure QUE (p < 0.01). Hence, the present study confirms the amorphous COS could be applied as a promising hydrophilic matrix in QUE-COS ASDs for enhancing dissolution performance and bioavailability of QUE.

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