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1.
Mol Cell ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33932349

RESUMO

Cholesterol metabolism is tightly associated with colorectal cancer (CRC). Nevertheless, the clinical benefit of statins, the inhibitor of cholesterol biogenesis mevalonate (MVA) pathway, is inconclusive, possibly because of a lack of patient stratification criteria. Here, we describe that YAP-mediated zinc finger MYND-type containing 8 (ZMYND8) expression sensitizes intestinal tumors to the inhibition of the MVA pathway. We show that the oncogenic activity of YAP relies largely on ZMYND8 to enhance intracellular de novo cholesterol biogenesis. Disruption of the ZMYND8-dependent MVA pathway greatly restricts the self-renewal capacity of Lgr5+ intestinal stem cells (ISCs) and intestinal tumorigenesis. Mechanistically, ZMYND8 and SREBP2 drive the enhancer-promoter interaction to facilitate the recruitment of Mediator complex, thus upregulating MVA pathway genes. Together, our results establish that the epigenetic reader ZMYND8 endows YAP-high intestinal cancer with metabolic vulnerability.

2.
Biosens Bioelectron ; 182: 113188, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33799030

RESUMO

Food safety is currently a significant issue for human life and health. Various fluorescent nanomaterials have been applied in the point-of-care test (POCT) for food safety as labeling materials. However, previous fluorescent nanomaterials can cause aggregation-caused quenching (ACQ), thus reducing the detection sensitivity. Conversely, aggregation-induced emission luminogens (AIEgens) are promising candidates for POCT in the food safety field because they can enhance detection sensitivity and throughput. Mycotoxins, such as aflatoxin B1 (AFB1) and cyclopiazonic acid (CPA), are a primary threat to human life and health and a significant food safety issue, and their on-site detection from farm to table is needed. Herein, an ultrasensitive point-of-care test was developed based on TPE-Br, a blue-emissive tetraphenylethylene derivative AIEgen. Under optimal conditions, this AIEgen-based lateral-flow biosensor (ALFB) allowed for a rapid response of 8 min toward AFB1 and CPA detection, with considerable sensitivities of 0.003 and 0.01 ng/mL in peanut matrices, respectively. In peanut matrices, the recoveries were 90.3%-110.0% for both mycotoxins, with relative standard deviations (RSDs) below 6%. The ALFB was further validated via UPLC-MS/MS using spiked peanut samples. AIEgens open an avenue for on-site, ultrasensitive, high-throughput detection methods and can be extensively used in point-of-care tests in food safety.

3.
J Phys Chem A ; 125(15): 3088-3094, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33830768

RESUMO

Charge separation and intersystem crossing play critical roles in various applications of organic long persistent luminescence materials, including light-emitting diodes, chemical sensors, theranostics, and many biomedical and information applications. Using first-principles calculations, we demonstrate that an azobenzene acting as a photoswitch can be used for altering the configuration of a donor-switch-acceptor (D-S-A) molecular system to ensure charge separation and promote intersystem crossing upon photoexcitation. The trans to cis photoisomerization of an azobenzene switch creates an electron trap that stabilizes the charge-separated state. The cis conformation further facilitates the singlet to triplet intersystem crossing in the excited state. Our theoretical study of the D-S-A system may help the design of long persistent luminescent organic devices.

4.
Shock ; 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33927136

RESUMO

GOAL: The derived hourly urine output (UO) indexed by body weight is one of the major criteria for the diagnosis of acute kidney injury (AKI). However, it is unclear whether actual body weight (ABW) or ideal body weight (IBW) should be used. This study aims to explore whether UO calculation based on ABW might lead to overestimation of AKI. METHOD: AKI patients identified in the Medical Information Mart for Intensive Care III (MIMIC-III) database by different components of the Kidney Disease Improving Global Outcomes (KDIGO) guidelines and different definitions of body weight were retrospectively studied. Hospital and 90-day mortality were compared to decide whether different patient groups had the same outcome. RESULTS: In the cohort of 14,725 patients, AKI was identified in 4,298 (29.19%) and 3,060 (20.78%) patients respectively when ABW or IBW was used (p < 0.01). Multivariate logistic regression revealed that AKI patients identified by UO calculated from ABW had similar hospital and 90-day mortality to that of patients with no evidence of AKI. Whereas AKI patients identified by serum creatinine (SCr) or by both ABW and IBW had twice higher the risks of hospital death, about 1.5 times higher the risks of 90-day death respectively compared with patients with no evidence of AKI. Results were confirmed in two separate sensitivity analysis where patients whose admission creatinine levels were within the normal reference ranges and patients identified as sepsis were studied. CONCLUSIONS: Calculating hourly body weight normalized UO using ABW may lead to underestimation of UO and overestimation of AKI.

5.
Sci Rep ; 11(1): 9321, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33927308

RESUMO

The prognostic factors and optimal treatment for the elderly patient with glioblastoma (GBM) were poorly understood. This study extracted 4975 elderly patients (≥ 65 years old) with histologically confirmed GBM from Surveillance, Epidemiology and End Results (SEER) database. Firstly, Cumulative incidence function and cox proportional model were utilized to illustrate the interference of non-GBM related mortality in our cohort. Then, the Fine-Gray competing risk model was applied to determine the prognostic factors for GBM related mortality. Age ≥ 75 years old, white race, size > 5.4 cm, frontal lobe tumor, and overlapping lesion were independently associated with more GBM related death, while Gross total resection (GTR) (HR 0.87, 95%CI 0.80-0.94, P = 0.010), radiotherapy (HR 0.64, 95%CI 0.55-0.74, P < 0.001), chemotherapy (HR 0.72, 95%CI 0.59-0.90, P = 0.003), and chemoRT (HR 0.43, 95%CI 0.38-0.48, P < 0.001) were identified as independently protective factors of GBM related death. Based on this, a corresponding nomogram was conducted to predict 3-, 6- and 12-month GBM related mortality, the C-index of which were 0.763, 0.718, and 0.694 respectively. The calibration curve showed that there was a good consistency between the predicted and the actual mortality probability. Concerning treatment options, GTR followed by chemoRT is suggested as optimal treatment. Radiotherapy and chemotherapy alone also provide moderate clinical benefits.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33825103

RESUMO

To develop high-efficient biochar adsorbents, the effects and mechanisms of oxidant modification and acid modification on Cd(II) adsorption by rice straw biochar were investigated. Three rice straws from Langxi in Anhui Province, Yingtan in Jiangxi Province, and Lianyungang in Jiangsu Province were collected to prepare biochars by anaerobic pyrolysis in a muffle furnace. Rice straw biochars were modified by 15% H2O2 and 1:1 HNO3/H2SO4 mixed acid, respectively, to obtain modified biochars. The untreated rice straw biochar and HCl-treated rice straw biochar with carbonate removed were used as controls. The functional groups on the surfaces of the biochars were qualitatively and quantitatively determined by Fourier transform infrared spectra and Boehm titration, respectively. The adsorption and desorption of Cd(II) onto and from the biochars and modified biochars were measured under various pH conditions. The results showed that oxidant modification with 15% H2O2 and acid modification with 1:1 HNO3/H2SO4 significantly increased the number of carboxyl functional groups on the surfaces of the biochars, and acid modification was more effective than oxidant modification in amplifying carboxyl functional groups on the surfaces of the biochars. The increase of surface functional groups effectively enhanced the specific adsorption of Cd(II) on the modified biochars. Therefore, both oxidant modification and acid modification enhanced the adsorption of Cd(II) on the biochars through increasing functional groups on the surfaces of the biochars.

8.
Comput Math Methods Med ; 2021: 5594973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833824

RESUMO

Introduction: Tripartite motif 47 (TRIM47) belongs to a category of the TRIM family. It takes part in cancer tumorigenesis, thus demonstrating important functions across numerous carcinomas. Unfortunately, it is still elusive towards TRIM47 expression, characteristic, and biological function in brain gliomas. Methods: Public database analysis was applied to analyze TRIM47 expression, and quantitative real-time PCR (qRT-PCR) was applied to detect the expression of TRIM47 in 9 paired tissues of glioma. The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) databases were applied to evaluate the overall survival (OS). Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were applied to analyze differentially expressed gene (DEG) functions. In vitro experiments were performed to validate TRIM47-mediated effects on glioma cell proliferation, migration, and invasion. Results: Compared to that in normal tissues, TRIM47 expression was greatly higher in glioma tissues, and its expression level was associated with different grades of glioma. Our data indicated that highly expressed TRIM47 displayed an association with the poor prognosis of glioma patients. Ablating TRIM47 obviously impeded glioma cell invasion and migration. Conclusion: TRIM47 could modulate glioma cell proliferation, invasion, and migration. Highly expressed TRIM47 exhibited a correlation with poor prognosis. All data imply that TRIM47 is a probable biomarker for glioma and has the potentiality to become a newly generated target for glioma treatment.

9.
J Environ Manage ; 289: 112479, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33838465

RESUMO

Gypsum amendment is widely used to resolve alkalinity issues and implement sustainable management for bauxite residue disposal areas (BRDAs). Amended BRDAs under natural conditions suffer from long-term erosion processes. Nevertheless, the effect of erosion on amendment efficacy is rarely assessed. In this study, by integrating the geochemical modelling of PHREEQC and column leaching experiments, the dissolution of alkaline solids in bauxite residue (BR) and gypsum amendment, as well as their environmental behaviors, were determined through a 1-year simulated rainfall leaching experiment. The PHREEQC simulation results demonstrated that Na+ ion strength, CO2 partial pressure and rainfall, all affected the saturation index (SI) of calcite significantly and accelerated its corrosion, leading to the dissolution of gypsum and calcite in a relatively stable state. However, Na+ ion strength and rainfall significantly acted on the SI of gypsum, which lead to loss of Ca2+ and reduction of alkaline stability. In addition to the effects of Na+ and Ca2+ on the saturation concentration of gypsum and calcite solution, Na+ and Ca2+ also exhibited significant effects on the equilibrium of chemical species reactions. The column results confirmed that stability of gypsum and calcite was consistent with the simulation results of PHREEQC in the BRDAs environment. Furthermore, multiple linear regressions revealed differences in combined contributions of rainwater and atmospheric CO2 on the stability of calcite and gypsum. The PHREEQC simulation provides a new approach to predict long-term alkaline stability of BR as well as to establish sustainable remediation on BRDAs during erosion process.

10.
Environ Pollut ; 281: 116993, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33799210

RESUMO

To explore the relationship between Al phytotoxicity and the electrochemical characteristics of wheat root surfaces, a new chemical mechanism for tolerance of wheat to Al toxicity was initially proposed by conducting acute root elongation experiment, adsorption/desorption experiment, streaming potential determination, and infrared spectroscopy (ATR-FTIR) analysis respectively to classify the grade of Al tolerance of 92 wheat cultivars and quantitatively characterize the electrochemical properties of their root surfaces. Then a pot experiment was conducted with the screened wheat cultivars with different Al resistance grown on acid soils to verify their tolerance to Al toxicity. Results show that zeta potentials of the roots of 67 wheat cultivars at pH4.46 were significantly negatively correlated with Al(Ⅲ) adsorbed on the roots and their relative root elongation (P < 0.05), indicating that wheat roots with less negative charges is more tolerant to Al toxicity. Based on the mechanism, 14 Al-tolerant, 23 medium Al-tolerant and 30 Al-sensitive wheat cultivars were classified. The pot experiment reveals that the relative dry weight of Al-tolerant wheat cultivars was generally greater than that of medium Al-tolerant and Al-sensitive wheat cultivars and Al-tolerant wheat cultivars accumulate less Al in their shoots, which further verifies the relationship among charge characteristics, tolerance of wheat to Al toxicity, and Al uptake by wheat. The negative charges derived from organic functional groups on root surfaces could influence the exchangeable and complexed Al(Ⅲ) adsorbed on wheat roots and thereby affect Al tolerance of wheat cultivars. This finding not only provides a new perspective to screen Al-tolerant wheat cultivars and explain the mechanism of tolerance of wheat to Al toxicity, but is also useful for the prediction of differences in the uptake of Al in the shoots between Al-tolerant and Al-sensitive wheat cultivars, and finally contributes to the prevention of food security risk caused by Al in acid soils.

11.
Ying Yong Sheng Tai Xue Bao ; 32(4): 1213-1220, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33899389

RESUMO

Based on a long-term simulated acid rain experiment, soil N2O emission fluxes were measured using static chambers and the gas chromatography method in a coniferous and broadleaved mixed forest and a monsoon evergreen broadleaved forest in southern China. During the five-year observation periods (2014-2018), soil N2O emission fluxes in the two forests showed obvious seasonal variation. The soil N2O emission fluxes in wet season were significantly higher than that in dry season, with a large annual variation. Due to the decreases of precipitation, soil N2O emission fluxes of the two forests in 2017 and 2018 were generally low. Soil N2O emission flux was positively correlated with soil temperature and soil moisture. In the monsoon evergreen broadleaved forest, soil N2O emission flux in the control plot was 12.6 µg N2O·m-2·h-1. Soil N2O emission fluxes under the pH 3.5 and pH 3.0 treatments increased by 42.9% and 61.1%, respectively. Soil N2O emission was significantly increased under simulated acid rain in the monsoon evergreen broadleaved forest. Acid rain promoted soil N2O emission in the coniferous and broadleaved mixed forest, but without significant difference among the treatments. Under the scenario of increasing acid rain, soil N2O emission fluxes in typical subtropical southern China forests would increase, and the magnitude of such increase was different among forest types.


Assuntos
Chuva Ácida , Solo , China , Florestas , Óxido Nitroso/análise
12.
Inorg Chem ; 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33908756

RESUMO

Organic-inorganic hybrid metal-oxide clusters have been pursued for many years, benefiting from their abundant structures and prominent performances. Upon our exploration, a family of unusual mixed-heteroatom (SbIII, PIII)-directing lanthanoid (Ln)-inserted heteropolyoxotungstates (Ln-HPOTs), [(CH3)2NH2]2Na7H3[Ln4(HPIII)W8(H2O)12(H2ptca)2O28][SbIIIW9O33]2·27H2O [Ln = Ce3+ (1), La3+ (2), Pr3+ (3)], functionalized by 1,2,3-propanetricarboxylic acid (H3ptca) was achieved. The intriguing trimeric [Ln4(HPIII)W8(H2O)12(H2ptca)2O28][SbIIIW9O33]212- polyanion was established by two trivacant [B-α-SbIIIW9O33]9- segments mounted on both sides and one rare [HPIIIW4O18]8- segment at the bottom, which are bridged via an organic-inorganic hybrid [W4Ln4(H2O)12O10(H2ptca)2]14+ central moiety. Such Ln-HPOTs involving dual-heteroatom-directing mixed building blocks, and even simultaneously modified by tricarboxylic ligands, are rather unseen in polyoxometalate chemistry. Moreover, the detection of 17ß-estradiol through a 1-based electrochemical biosensor has been explored, demonstrating a low detection limit (7.08 × 10-14 M) and considerable stability.

13.
J Phys Chem Lett ; : 3868-3874, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33856794

RESUMO

Through-space charge transfer (TSCT) has become a thriving strategy of modulating photogenerated charges in organic photoresponsive molecular systems for potential applications in luminescence, optoelectronics, and photochemical conversion. Yet fixed configuration between electron donor (D) and acceptor (A) is disadvantageous to mitigate charge recombination undermining their performances. By carrying out first-principle simulations, we proposed a protocol enabling dynamic control of TSCT within a D-A system by use of a bridged azobenzene (BAB), whose configuration is self-adaptive upon photoexcitation. While the Z-isomer of BAB facilitates π-π stacking of D-A pair with designated frontier orbital alignment to ensure TSCT, the E-isomer of BAB breaks that stacking and restrains charge recombination. Further, as a CO2 molecule is weakly bound to the anionic acceptor, the former goes bent as a result of charge transfer from the latter, suggesting a path for photodriven CO2 reduction aided by such a donor-switch-acceptor system. Our proof-of-concept study shows the potential of using specific photoswitch to adaptively steer spatial electron transfer within stacked π systems toward photochemical conversion.

14.
Ophthalmology ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33857574

RESUMO

COVID-19 quarantine provides the largest intervention data of myopia progression in schoolchildren. We found grade is an important risk factor, and COVID-19-induced modifications of student's online time and outdoor activity time sufficiently change myopia progression.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33793196

RESUMO

Highly conductive domain walls in insulating ferroelectric LiNbO3 (LNO) single-crystal thin films with atomic smoothness are attractive for use in high-density integration of the ferroelectric domain wall random access memory (DWRAM) because of their excellent reliability and high read currents. However, downscaling of the memory size to the nanoscale could cause poor polarization retention. Understanding the size-dependent electrical performance of a memory cell is therefore crucial. In this work, highly insulating X-cut LNO thin films were bonded to SiO2/Si wafers and lateral mesa-like cells were fabricated on the film surfaces, where contact occurred with two-sided electrodes along the polar z-axis. Under application of an in-plane electric field above a coercive field (Ec), the domain within each memory cell was switched to be antiparallel to the unswitched referencing domain at the bottom; this resulted in the formation of a conducting domain wall, which enables the nondestructive readout strategy of the DWRAM. The cell, which has a lateral length (l) above a critical size (l0) of 105 nm, is found to be a mixture of two phases across the cell area. The inner area of the cell suffers from poor polarization retention because Ec = 150 kV/cm, as demonstrated by in-plane piezoresponse force microscopy imaging. In comparison, the outer periphery domains, which have lengths of 70 nm (∼l0/2), show good retention but require a much higher Ec of 785 kV/cm. The relevant physics is discussed as phase reconstruction occurs after release of the in-plane compressive strain near the outer regions; the results show good agreement with those of one-dimensional thermodynamic calculations and phase-field simulations. The measured current-voltage curves demonstrated a sudden enhancement of the wall current across the cell when l < l0, thus implying higher readout wall currents and better retention for the DWRAM at higher storage densities.

16.
New Phytol ; 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33774829

RESUMO

Plant virus movement proteins (MPs) facilitate virus spread in their plant hosts, and some of them are known to target plasmodesmata (PD). However, how the MPs target PD is still largely unknown. Carrot mottle virus (CMoV) encodes the ORF3 and ORF4 proteins, which are involved in CMoV movement. In this study, we used CMoV as a model to study the PD targeting of a plant virus MP. We showed that the CMoV ORF4 protein, but not the ORF3 protein, modified PD and led to the virus movement. We found that the CMoV ORF4 protein interacts with the host cell small ubiquitin-like modifier (SUMO) 1, 2 and the SUMO-conjugating enzyme SCE1, resulting in the ORF4 protein SUMOylation. Downregulation of mRNAs for NbSCE1 and NbSUMO impaired CMoV infection. The SUMO-interacting motifs (SIMs) LVIVF, VIWV, and a lysine residue at position 78 (K78) are required for the ORF4 protein SUMOylation. The mutation of these motifs prevented the protein to efficiently target PD, and further slowed or completely abolished CMoV systemic movement. Finally, we found that some of these motifs are highly conserved among umbraviruses. Our data suggest that the CMoV ORF4 protein targets PD by interacting with the host cell SUMOylation system.

17.
FASEB J ; 35(5): e21469, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33788981

RESUMO

Mycotoxins are toxic secondary metabolites produced by food-contaminating fungi, which lead to global epigenetic changes and cause toxicity to both farm animals and humans. However, whether mycotoxins induce gene-specific epigenetic alterations associated with inducible downstream gene expression is unclear as are the underlying regulatory mechanisms. Here, we found that T-2 toxin and its deacetylated metabolites but not deoxynivalenol (DON) or other representative mycotoxins highly induced the expression of cytochrome P450 1A4 (CYP1A4) in both Leghorn male hepatoma (LMH) cells and chicken primary hepatocytes, and this effect was related to the regulation of both aryl hydrocarbon receptor (AhR) and DNA methylation. We used methylation-sensitive restriction enzyme digestion-qPCR (MSRE-qPCR) and chromatin immunoprecipitation (ChIP) assays and found that the binding of DNA methyltransferase 1 (DNMT1) and histone deacetylase 2 (HDAC2) to highly methylated CpG island 3-2 at the enhancer of CYP1A4 was accompanied by the recruitment of the repressive histone modification marker H3K27me3, inducing a silent state. In turn, T-2 toxin stimulation enriched the binding of AhR to demethylated CpG island 3-2, which facilitated p300 and H3K9ac recruitment and ultimately generated an activated chromatin structure at the enhancer by increasing the active histone modification markers, including H3K4me3, H3K27ac, and H3K14ac. Interestingly, T-2 toxin-induced AhR activation also facilitated RNA polymerase II binding to CpG island 2, which may form a transcriptionally active chromatin structure at the promoter and ultimately transactivate CYP1A4. Our findings provide novel insights into the epigenetic regulation of T-2 toxin-induced gene expression.

18.
Catheter Cardiovasc Interv ; 97 Suppl 2: 988-995, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33734575

RESUMO

OBJECTIVES: This study sought to compare the efficacy and clinical safety of the LONGTY drug-coated balloon (DCB) with those of SeQuent Please DCB in patients with in-stent restenosis (ISR). BACKGROUND: Although DCB technologies have evolved, little is known about the clinical efficacy of the new-generation LONGTY DCB. METHODS: This was a prospective, multicenter, randomized, noninferiority trial comparing LONGTY DCB with SeQuent Please DCB in patients with ISR. The primary endpoint was target lesion late lumen loss at 9 months' follow-up. RESULTS: A total of 211 patients with ISR from 13 Chinese sites were included (LONGTY DCB, n = 105; SeQuent Please DCB, n = 106). Device success was achieved in all patients. At the 9 month angiographic follow-up, target lesion late lumen loss was 0.35 ± 0.42 mm with LONGTY and 0.38 ± 0.45 mm with SeQuent Please (p for noninferiority <.001). The target lesion revascularization rates at 1 year were similar in both DCB groups (15.24 vs. 13.21%; p = .673). Over an extended follow-up of 2 years, the clinical endpoints, including cardiac death, myocardial infarction, and thrombus rate, were extremely low and similar in both groups. CONCLUSIONS: In this multicenter, head-to-head, randomized trial, the new-generation LONGTY DCB was noninferior to the SeQuent Please DCB for the primary endpoint of target lesion late lumen loss at 9 months.

19.
Nanoscale ; 13(12): 6105-6116, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33729238

RESUMO

Bleeding in outdoor environments is often accompanied by bacterial infection. Due to poor outdoor conditions, it is essential to use the same materials to achieve one-stop treatment of fast hemostasis and simultaneously sterilizing bacteria, especially multidrug-resistant bacteria. Photodynamic therapy (PDT) can kill superbacteria, and local PDT through a nanofiber platform can effectively reduce damage to normal tissue. However, current photosensitizers whether in the interior or on the surface of fibers would leak into the wound and inhibit collagen regeneration. Herein, we use a battery-powered handheld electrospinning device that can work outdoors. It directly spins fibers onto the wound, which facilitates fast hemostasis due to its excellent adhesion to the wound. Eluting holes in the hydrophobic fibers by wound tissue fluid are also proposed to accelerate the escape of reactive oxygen species (ROS) from the interior of the fibers to the wound. After photosensitizers were coated on upconverting nanoparticles (UCNPs), they formed clusters whose size (∼55 nm) was much larger than the uniform elution hole (∼4 nm), which prevented photosensitizers from leaking out into the wound tissue. This cluster structure can also tailor the photosensitizers to be triggered by near infrared (NIR) light, whose deeper penetration depth in tissue can facilitate treating deep infections. Because of the combination of the in situ fiber deposition method with the designed elution mode, ROS is effectively poured out onto the fiber surface and is quickly delivered to the wound. Thus, after rapid hemostasis (<7 s), this one-stop treatment followed by photodynamic sterilizing of superbacteria can promote collagen regeneration and reduce wound healing time from 24 to 16 days.

20.
Sci Total Environ ; 780: 146600, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33774305

RESUMO

Phosphogypsum (PG) is an industry solid waste produced from phosphoric acid manufacture. To reduce environmental pollution of the PG, H2C2O4 was employed to purify it, which then can be used for cement production. The optimal concentration of H2C2O4 for PG purification was determined. In addition, differential thermal analysis (DTA), X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence (XRF) were used to determine the removal of phosphate impurity in PG. The effects of purified PG on cement hydration and the environmental implications were also investigated. The results demonstrate that H2C2O4 can remove the intercrystalline phosphate impurities by destroying the part of the crystal structure of gypsum. With the best treatment concentration of 1% H2C2O4, 77.7% of phosphate impurity (as P2O5) was removed from PG, which subsequently shortened the final setting time down to 220 min and successfully met the national standard (GB 175-1999). Portland cement prepared by the 1% H2C2O4 treated PG possessed a comparable 3d compressive strength of 20.8 MPa and a 28d compressive strength of 44.6 MPa. It is concluded that PG purified by 1% H2C2O4 treatment can be used for cement production. Meanwhile, this H2C2O4 treatment can effectively reduce the environmental pollution from PG and offer a sustainable method for the utilization of PG.

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