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1.
Ann Vasc Surg ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599487

RESUMO

PURPOSE: This study aims to conduct a comparative analysis of the clinical efficacy and safety between pharmacomechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT) in the context of acute lower-extremity deep venous thrombosis (LEDVT). MATERIALS AND METHODS: A retrospective review of our institution's patient database spanning from February 2011 to December 2019 was performed to identify cases of acute LEDVT. The patients were categorized into two distinct groups based on the thrombolytic interventions administered: the PMT group, specifically denoting PMT with AngioJet in our investigation, and the CDT group. Comprehensive data sets encompassing patient demographics, risk factors, procedural specifics, thrombolysis grading, and complications were collected. Subsequent follow-up evaluations at the two-year mark post-treatment included assessments of post-thrombotic syndrome (PTS) and the quality of life (QOL). RESULTS: Among the 348 patients identified (mean age: 50.12 ± 15.87 years; 194 females), 200 underwent catheter-directed thrombolysis (CDT) during the early stage (2011 to 2017), while 148 received pharmacomechanical thrombectomy (PMT) between 2017 and 2019. Baseline data between the two groups exhibited no statistically significant differences. Thrombus scores significantly decreased in both cohorts post-therapy (each p < 0.001).Patients subjected to PMT demonstrated higher thrombolysis rates (77.35±9.44% vs 50.85±6.72%), reduced administration of the thrombolytic agent urokinase [20(20-20) vs 350(263-416), p < 0.001], larger limb circumference differences (above the knee: 6.03±1.76cm vs 4.51±1.82cm, p < 0.001; below the knee: 2.90±1.16cm vs 2.51±0.90cm, p < 0.001), and shorter lengths of stay (7.19±3.11 days vs 12.33±4.77 days, p < 0.001). However, the PMT group exhibited a higher decline in hemoglobin levels (13.41±10.59 g/L vs 10.88±11.41 g/L, p = 0.038) and an increase in creatinine levels [9.58(2.32-15.82) umol/L vs 4.53(2.87-6.08) umol/L, p < 0.001] compared to the CDT group. No statistically significant differences were observed in the numbers of balloon angioplasty, stent implantation (each p > 0.050), and minor and major complications between the two groups. At the 1-year follow-up, post-thrombotic syndrome (PTS) occurred in 13.51% of the PMT group compared to 26% of the CDT group (p = 0.025), with a higher incidence of moderate-severe PTS in the CDT group (8% vs 2.7%, p = 0.036). At the 2-year follow-up, PTS was observed in 16.2% of the PMT group and 31.5% in the CDT group, p = 0.004. Preoperative and postoperative D-values of SF-36 PCS and SF-36 MCS showed no statistically significant between-group differences. CONCLUSION: In our institutional experience, both pharmacomechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT) have proven to be effective and safe therapeutic approaches for managing acute lower-extremity deep venous thrombosis (LEDVT). PMT, in particular, demonstrated superior efficacy in achieving thrombosis resolution and mitigating the risk of post-thrombotic syndrome, affirming its role as a favorable intervention in this clinical context.

2.
J Adhes Dent ; 26(1): 79-86, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38465402

RESUMO

PURPOSE: This investigation aimed to assess the impact of additive manufacturing-generated surface textures on zirconia bond strength. MATERIALS AND METHODS: Zirconia samples (n = 144) fabricated using digital light-processing (DLP) technology were categorized into 6 groups according to the type of surface conditioning (group NN: no designs, no air abrasion; group NY: no designs, with air abrasion; group GN: groove designs, no air abrasion; group GY: groove designs with air abrasion; group HN: hexagon grid, no air abrasion; group HY: hexagon grid, with air abrasion). Composite resin cylinders were cemented to the treated zirconia surfaces with dual-curing, self-adhesive resin cement (Clearfil SA Luting). The shear bond strength (SBS) was tested after water storage for 3 days or 3 days with an additional 10,000 thermocycles. RESULTS: The zirconia samples fabricated using DLP technology have high accuracy. The SBS of the NY, GY, and HY groups did not significantly differ after 3 days, and neither did the SBS of the NN, GN, and HN groups. The NN, NY, and HY groups exhibited reduced SBS compared to their initial values following artificial aging, while the SBS of the remaining three groups were not diminished. The GY group obtained the highest SBS value after aging. CONCLUSION: Printing grooves with air abrasion can improve the bond strength.


Assuntos
Colagem Dentária , Abrasão Dental por Ar , Propriedades de Superfície , Cimentos de Resina/química , Resinas Compostas , Resistência ao Cisalhamento , Zircônio/química , Teste de Materiais , Análise do Estresse Dentário
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124195, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38547782

RESUMO

The carbon dots (CDs) with excellent optical properties and their hydrogel complex are of great significance in biomedicine, healthcare and biochemical detection fields. This paper reports the preparation of green-emitting CDs (MA-CDs) through one-step hydrothermal route with citric acid as reducing agent, L-malic acid as carbon source and N-(2-hydroxyethyl)ethylenediamine as nitrogen source. To expand its application in biology, MA-CDs were coupled with vancomycin to obtain multifunctional CDs (VMA-CDs). The prepared VMA-CDs exhibit selective antibacterial behavior to Gram-positive bacteria, and it could be used as a fluorescent probe to selectively label Staphylococcus aureus (S. aureus). Moreover, thanks to the excellent optical properties of VMA-CDs, it has been used as a fluorescent sensor to detect Au3+ with detection range of 6.50 nM-21.93 µM and detection limit 3.98 nM. By introducing the fluorescence of CDs as the reference signal, and VMA-CDs as a response signal, the hydrogel (V-SP) was prepared and realized the detection of Au3+ in microfluidics with assistance of a smartphone to collect and analyze data.


Assuntos
Hidrogéis , Pontos Quânticos , Pontos Quânticos/química , Carbono/química , Staphylococcus aureus , Antibacterianos/farmacologia , Corantes Fluorescentes/química , Nitrogênio/química , Espectrometria de Fluorescência
4.
J Environ Manage ; 356: 120726, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537456

RESUMO

Electrochemical technology is a promising technique for separating ammonia from mature landfill leachate. However, the accompanying migration and transformation of coexisting pollutants and strategies for further high-value resourceful utilization of ammonia have rarely received attention. In this study, an electrochemical separation-Rhodopseudomonas palustris electrolysis cell coupled system was initially constructed for efficient separation and conversion of nitrogen in mature landfill leachate to microbial protein with synchronously tracking the transport and conversion of coexisting heavy metals accompanying the process. The results revealed that ammonia concentration in the cathode increased from 40.3 to 49.8% with increasing the current density from 20 to 40 mA/cm2, with less than 3% of ammonia transformation to NO2--N and NO3--N. During ammonia separation, approximately 95% of HM-DOMs (Cr, Cu, Ni, Pb, and Zn) were released into the anolyte due to humus degradation and further diffused to the cathode. A significant correlation was observed between the releases of HM-DOMs. Cu-DOMs accounted for 70.2% of the total Cu content, which was the highest proportion among the heavy metals (HMs). Among the HMs in anolyte, 57.4% of Pb, 52.5% of Ni, and 50.6% of Zn diffused to the cathode, and most of the HMs were removed in the form of hydroxide precipitations due to heavy alkaline catholyte. Compared with the open-circuit condition, the utilization efficiency of NH4+-N in the R. palustris electrolysis cell increased by 445.1% with 47% and 50% increases in final NH4+-N conversion rate and R. palustris biomass, respectively, due to bio-electrochemical enhanced phototrophic metabolism and acid generation for buffering the strong alkalinity of the electrolyte to maintain suitable growth conditions for R. palustris.


Assuntos
Amônia , Rodopseudomonas , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Chumbo , Eletrólise , Instalações de Eliminação de Resíduos , Nitrogênio
5.
J Hazard Mater ; 467: 133667, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38325102

RESUMO

Activated sludge extracellular polymeric substances (ASEPSs) comprise most dissolved organic matters (DOMs) in the tail water. However, the understanding of the link between the photolysis of antibiotic and the photo-reactivity/photo-persistence of ASEPS components is limited. This study first investigated the photochemical behaviors of ASEPS's components (humic acids (HA), hydrophobic substances (HOS) and hydrophilic substances (HIS)) separated from municipal sludge's EPS (M-EPS) and nitrification sludge's EPS (N-EPS) in the photolysis of sulfadiazine (SDZ). The results showed that 60% of SDZ was removed by the M-EPS, but the effect in the separated components was weakened, and only 24% - 39% was degraded. However, 58% of SDZ was cleaned by HOS in N-EPS, which was 23% higher than full N-EPS. M-EPS components had lower steady-state concentrations of triplet intermediates (3EPS*), hydroxyl radicals (·OH) and singlet oxygen (1O2) than M-EPS, but N-EPS components had the highest concentrations (5.96 ×10-15, 8.44 ×10-18, 4.56 ×10-13 M, respectively). The changes of CO, C-O and O-CO groups in HA and HOS potentially correspond to reactive specie's generation. These groups change little in HIS, which may make it have radiation resistance. HCO-3 and NO-3 decreased the indirect photolysis of SDZ, and its by-product N-(2-Pyrimidinyl)1,4-benzenediamine presents high environmental risk.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Esgotos , Esgotos/química , Matriz Extracelular de Substâncias Poliméricas/química , Sulfadiazina/análise , Antibacterianos/análise , Fotólise , Substâncias Húmicas/análise
6.
Environ Res ; 247: 118158, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224936

RESUMO

Existing wastewater treatment technologies face the key challenge of simultaneously removing emerging contaminants and nutrients from wastewater efficiently, with a simplified technological process and minimized operational costs. In this study, a novel alginate-embedded magnetic biochar-anoxygenic photosynthetic bacteria composite microspheres (CA-MBC-PSB microspheres) was prepared for efficient, cost-effective and one-step removal of antibiotics and NH4+-N from wastewater. Our results demonstrated that the CA-MBC-PSB microspheres removed 97.23% of sulfadiazine (SDZ) within 7 h and 91% of NH4+-N within 12 h, which were 21.23% and 38% higher than those achieved by pure calcium alginate-Rhodopseudomonas palustris microspheres (53% and 45.7%), respectively. The enhanced SDZ and NH4+-N removal were attributed to the enhanced photoheterotrophic metabolism and excretion of extracellular photosensitive active substances from R. Palustris through the photo-bioelectrochemical interaction between R. Palustris and magnetic biochar. The long-term pollutants removal performance of the CA-MBC-PSB microspheres was not deteriorated but continuously improved with increasing ruse cycles with a simultaneous removal efficiency of 99% for SDZ and 92% for NH4+-N after three cycles. The excellent stability and reusability were due to the fact that calcium alginate acts as an encapsulating agent preventing the loss and contamination of R. palustris biomass. The CA-MBC-PSB microspheres also exhibited excellent performance for simultaneous removal of SDZ (89% in 7 h) and NH4+-N (90.7% in 12 h) from the secondary effluent of wastewater treatment plant, indicating the stable and efficient performance of CA-MBC-PSB microspheres in practical wastewater treatment.


Assuntos
Alginatos , Carvão Vegetal , Águas Residuárias , Microesferas , Sulfadiazina , Fenômenos Magnéticos
7.
Materials (Basel) ; 16(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37763350

RESUMO

Veneered zirconia ceramics are widely used for dental restorations. However, the relatively poor bonding strength between the ceramic core and veneer porcelain remains a common problem in clinical applications. To address this issue, this study focused on enhancing the core-veneer bond strength of zirconia restorations through the implementation of surface textures using digital light processing (DLP) technology. The light intensity was precisely tuned to optimize mechanical strength and minimize light scattering. Subsequently, hexagonal or square grids were printed on the surface of the zirconia ceramic core. Following veneering procedures, the shear bond strength (SBS) test was conducted using a universal testing machine. Dates were compared using analysis of variance (ANOVA) and the least significant difference (LSD) test. Furthermore, optical microscopy and scanning electron microscopy (SEM) were used to examine the failure modes and observe the cross-sectional structures, respectively. The results indicated that the presence of a 0.09 mm high hexagon grid led to a significant 21% increase in the SBS value. However, grids with heights of 0.2 and 0.3 mm showed less improvement, owing to the formation of large defects at the interface during the fusion process. This study demonstrated the potential of DLP technology in preparing zirconia ceramics with complex structures and high mechanical strength, thereby offering promising solutions for overcoming challenges associated with dental applications.

8.
Front Microbiol ; 14: 1168179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303801

RESUMO

Introduction: The root-knot nematodes (RKN), especially Meloidogyne spp., are globally emerging harmful animals for many agricultural crops. Methods: To explore microbial agents for biological control of these nematodes, the microbial communities of the rhizosphere soils and roots of sponge gourd (Luffa cylindrica) infected and non-infected by M. incognita nematodes, were investigated using culture-dependent and -independent methods. Results: Thirty-two culturable bacterial and eight fungal species, along with 10,561 bacterial and 2,427 fungal operational taxonomic units (OTUs), were identified. Nine culturable bacterial species, 955 bacterial and 701 fungal OTUs were shared in both four groups. More culturable bacterial and fungal isolates were detected from the uninfected soils and roots than from the infected soils and roots (except no fungi detected from the uninfected roots), and among all samples, nine bacterial species (Arthrobacter sp., Bacillus sp., Burkholderia ambifaria, Enterobacteriaceae sp., Fictibacillus barbaricus, Microbacterium sp., Micrococcaceae sp., Rhizobiaceae sp., and Serratia sp.) were shared, with Arthrobacter sp. and Bacillus sp. being dominant. Pseudomonas nitroreducens was exclusively present in the infested soils, while Mammaliicoccus sciuri, Microbacterium azadirachtae, and Priestia sp., together with Mucor irregularis, Penicillium sp., P. commune, and Sordariomycetes sp. were found only in the uninfected soils. Cupriavidus metallidurans, Gordonia sp., Streptomyces viridobrunneus, and Terribacillus sp. were only in the uninfected roots while Aspergillus sp. only in infected roots. After M. incognita infestation, 319 bacterial OTUs (such as Chryseobacterium) and 171 fungal OTUs (such as Spizellomyces) were increased in rhizosphere soils, while 181 bacterial OTUs (such as Pasteuria) and 166 fungal OTUs (such as Exophiala) rose their abundance in plant roots. Meanwhile, much more decreased bacterial or fungal OTUs were identified from rhizosphere soils rather than from plant roots, exhibiting the protective effects of host plant on endophytes. Among the detected bacterial isolates, Streptomyces sp. TR27 was discovered to exhibit nematocidal activity, and B. amyloliquefaciens, Bacillus sp. P35, and M. azadirachtae to show repellent potentials for the second stage M. incognita juveniles, which can be used to develop RKN bio-control agents. Discussion: These findings provided insights into the interactions among root-knot nematodes, host plants, and microorganisms, which will inspire explorations of novel nematicides.

9.
Polymers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904372

RESUMO

To avoid risk, spacecraft docking technologies can transport batches of different astronauts or cargoes to a space station. Before now, spacecraft-docking multicarrier/multidrug delivery systems have not been reported on. Herein, inspired by spacecraft docking technology, a novel system including two different docking units, one made of polyamide (PAAM) and on of polyacrylic acid (PAAC), grafted respectively onto polyethersulfone (PES) microcapsules, is designed, based on intermolecular hydrogen bonds in aqueous solution. VB12 and vancomycin hydrochloride were chosen as the release drugs. The release results show that the docking system is perfect, and has a good responsiveness to temperature when the grafting ratio of PES-g-PAAM and PES-g-PAAC is close to 1:1. Below 25 °C, this system exhibited an "off" effect because the polymer chains on the microcapsule's surface produced intermolecular hydrogen bonds. Above 25 °C, when the hydrogen bonds were broken, the microcapsules separated from each other, and the system exhibited an "on" state. The results provide valuable guidance for improving the feasibility of multicarrier/multidrug delivery systems.

10.
Opt Express ; 31(1): 301-312, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606968

RESUMO

All-inorganic halide perovskite CsPbX3(X = Br/Cl/I)quantum dots have gained a considerable attention in the optoelectronic fields. However, the high cost and poor stability of the prepared CsPbX3 quantum dots (QDs) are inevitable challenges for their future practical applications. And the high-performance CsPbX3 QDs are always needed. Herein, a facile and low-cost synthesis scheme was adopted to prepare the CsPbBr3 QDs modified by lead bromide (PbBr2) and tetraoctylammonium bromide (TOAB) ligands at room temperature in open air. The prepared CsPbBr3 QDs exhibited a high photoluminescence quantum yield (PLQY) of 96.6% and a low amplified spontaneous emission (ASE) threshold of 12.6 µJ/cm2. Stable ASE intensity with little degradation was also realized from the CsPbBr3 QDs doped with PMMA. Furthermore, the enhanced ASE properties of the CsPbBr3 QDs-doped PMMA based on distributed feedback (DFB) substrate was achieved with a lower threshold of 3.6 µJ/cm2, which is 28.6% of that of the (PbBr2 + TOAB)-treated CsPbBr3 QDs without PMMA. This work exhibits a promising potential in the on-chip light source.

11.
Open Med (Wars) ; 17(1): 1999-2012, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561847

RESUMO

The oncogenic role of lncRNA ELFN1-AS1 has been described in different cancers, including colon cancer (CC). However, how ELFN1-AS1 regulates CC malignancy remains unclear. In this study, ELFN1-AS1, AURKB, and miR-4270 expression levels in CC cells and tissues were determined using RT-qPCR and western blotting. CCK-8 and wound healing assays were also performed to analyze alterations in CC cell proliferation and migration. The expression of apoptosis-related proteins (Bax and Bcl-2) was determined via western blot analysis. RNA immunoprecipitation (RIP) assays coupled with luciferase reporter assays were employed to verify the relationship between miR-4270, ELFN1-AS1, and AURKB. An in vivo assay was performed using xenograft tumors in mice to detect the change of tumor growth. It was found that AURKB and ELFN1-AS1 expression was upregulated, whereas miR-4270 was downregulated in CC cells and tissues. ELFN1-AS1 silencing exhibited anti-proliferative, anti-migratory, and pro-apoptotic effects in CC cells. The tumor-suppressive effect of ELFN1-AS1 silencing was verified using in vivo assays. MiR-4270 was predicted to be a target of ELFN1-AS1 and AURKB as a target of miR-4270. Their interactions were further elucidated using luciferase reporter and RNA RIP assays. More importantly, treatment with a miR-4270 inhibitor not only rescued the tumor-suppressing effect of ELFN1-AS1 silencing but also abrogated the tumor suppressor functions of AURKB silencing in CC cells. Taken together, the ELFN1-AS1/miR-4270/AURKB axis facilitates CC tumorigenesis; therefore, targeting this axis might be a promising intervention in preventing CC progression.

12.
Pestic Biochem Physiol ; 188: 105286, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36464339

RESUMO

The core elements of entomopathogenic nematode toxicity towards the fall armyworm Spodoptera frugiperda are associated with symbiotic bacteria. These microbes provide independent control effects and are reported to have repellency to insect pests. However, the ecological background of this nematode-bacteria-insect communication module is elusive. This work aims to identify key chemical cues which drive the trophic interactions through olfactory reception of S. frugiperda, and to inspire implementations with these isolated behavioral regulators in the corn field. A total of 657 volatiles were found within 13 symbiotic bacterial strains, and five of them induced significant electrophysiological responses of S. frugiperda larvae. 2-Hexynoic acid was demonstrated to exhibit a dominant role in deterring S. frugiperda larvae from feeding and localization. Field implementations with this novel volatile deterrent have resulted in fortified nematode applications. 2-Hexynoic acid acts as an excellent novel deterrent and presents remarkable application potential against fall armyworm larvae. Emissions from symbiotic bacteria of entomopathogenic nematodes are key players in chemical communication among insects, nematodes, and microbes. The olfactory perceptions and molecular targets for this volatile are worthy of future research.


Assuntos
Bactérias , Nematoides , Animais , Larva , Spodoptera , Zea mays
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(7): 759-764, 2022 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-35894190

RESUMO

OBJECTIVES: To study the early clinical efficacy of combined therapy of stage 4 neuroblastoma. METHODS: A retrospective analysis was performed on the medical data and follow-up data of 14 children with stage 4 neuroblastoma who were diagnosed in Hong Kong University-Shenzhen Hospital from January 2016 to June 2021. RESULTS: The median age of onset was 3 years and 7.5 months in these 14 children. Among these children, 9 had positive results of bone marrow biopsy, 4 had N-Myc gene amplification, 13 had an increase in neuron-specific enolase, and 7 had an increase in vanilmandelic acid in urine. Based on the results of pathological examination, differentiated type was observed in 6 children, undifferentiated type in one child, mixed type, in one child and poorly differentiated type in 6 children. Of all the children, 10 received chemotherapy with the N7 regimen (including 2 children receiving arsenic trioxide in addition) and 4 received chemotherapy with the Rapid COJEC regimen. Thirteen children underwent surgery, 14 received hematopoietic stem cell transplantation, and 10 received radiotherapy. A total of 8 children received Ch14.18/CHO immunotherapy, among whom 1 child discontinued due to anaphylactic shock during immunotherapy, and the other 7 children completed Ch14.18/CHO treatment without serious adverse events, among whom 1 child was treated with Lu177 Dotatate 3 times after recurrence and is still undergoing chemotherapy at present. The median follow-up time was 45 months for all the 14 children. Four children experienced recurrence within 2 years, and the 2-year overall survival rate was 100%; 4 children experienced recurrence within 3 years, and 7 achieved disease-free survival within 3 years. CONCLUSIONS: Multidisciplinary combined therapy is recommended for children with stage 4 neuroblastoma and can help them achieve better survival and prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neuroblastoma , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Terapia Combinada , Humanos , Lactente , Neuroblastoma/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Cintilografia , Estudos Retrospectivos , Resultado do Tratamento
14.
Polymers (Basel) ; 15(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36616403

RESUMO

In this paper, we report a microcapsule embedded PNIPAN in P (TPC-EDA) shell and it can be regarded as an interpenetrating polymer network (IPN) structure, which can accelerate the penetration of oily substances at a certain temperature, and the microcapsules are highly monodisperse and dimensionally reproducible. The proposed microcapsules were fabricated in a three-step process. The first step was the optimization of the conditions for preparing oil in water emulsions by microfluidic device. In the second step, monodisperse polyethylene terephthaloyl-ethylenediamine (P(TPC-EDA)) microcapsules were prepared by interfacial polymerization. In the third step, the final microcapsules with poly(N-isopropylacrylamide) (PNIPAM)-based interpenetrating polymer network (IPN) structure in P(TPC-EDA) shells were finished by free radical polymerization. We conducted careful data analysis on the size of the emulsion prepared by microfluidic technology and used a very intuitive functional relationship to show the production characteristics of microfluidics, which is rarely seen in other literatures. The results show that when the IPN-structured system swelled for 6 h, the adsorption capacity of kerosene was the largest, which was promising for water-oil separation or extraction and separation of hydrophobic drugs. Because we used microfluidic technology, the products obtained have good monodispersity and are expected to be produced in large quantities in industry.

15.
J Colloid Interface Sci ; 579: 815-822, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32673858

RESUMO

Novel ternary nanohybrids, bifunctionalized graphene oxide/MnFe2O4 magnetic nanoparticles (PEHA-Phos-GO/MnFe2O4), were prepared by a facile method and applied for the removal of Pb(II) from aqueous solution. Attributing to the numerous amino and phosphate groups on the bifunctionalized GO nanosheets as well as the magnetic nanoparticles of MnFe2O4, PEHA-Phos-GO/MnFe2O4 demonstrated high removal efficiency of Pb(II) and rapid magnetic separation. The 366.4 mg/g maximum adsorption capacity of Pb(II) on PEHA-Phos-GO/MnFe2O4 was obtained at the optimal adsorption pH of 5.5, much higher than that on GO (212.1 mg/g). The kinetics and isotherm data indicated that the adsorption processes can be well described by the pseudo-second-order kinetics and the Langmuir model. For the adsorption of Pb(II) on PEHA-Phos-GO/MnFe2O4, thermodynamic studies revealed the endothermic nature of the spontaneous adsorption process. The exhibited adsorption capacity, easy magnetic separation and reusability make the PEHA-Phos-GO/MnFe2O4 nanohybrids very promising adsorbents for efficacious removal of heavy metals from aqueous solutions in environmental pollution cleanup.

16.
Polymers (Basel) ; 12(7)2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32605118

RESUMO

A novel reactive phosphorus and sulfur-containing monomer (bis(acryloxyethyldiphenylphosphate)sulfone, BADPS) was synthesized to enhance the comprehensive performance of unsaturated polyester resin (UPR),and corresponding flame-retardant unsaturated polyester resins (FR-UPRs) with various amounts of BADPS were prepared by radical bulk polymerization. The flame retardancy and thermal and mechanical properties of the UPR samples were investigated by limiting oxygen index (LOI) measurements, cone calorimetry, differential scanning calorimetry (DSC),a thermogravimetric analysis (TGA), and a tension test. The results showed that the introduction of BADPS remarkably enhanced the flame resistance and high-temperature stability, as well as the tensile performance of UPR. Scanning electron microscopy (SEM),Fourier transform infrared (FTIR), and Raman spectroscopy studies revealed that BADPS can efficaciously promote the formation of UPR char residue with an improved microstructure and increased graphitization degree, which enhancedthe high-temperature stability and char yield of UPR. Additionally, a thermogravimetry-Fourier transform infrared (TG-FTIR) analysis corroborated that the evolution of combustible volatiles from UPR decomposition was substantially restrained by the incorporation of BADPS, which is beneficial for the suppression of fire hazards in UPR.

17.
Appl Opt ; 57(32): 9562-9570, 2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-30461736

RESUMO

Diode-pumped alkali vapor lasers (DPALs) have been rapidly developed because of their excellent performances. However, there have been few reports about DPALs with multiple wavelengths until now. The effects of the output features on the waist size and position of both Rb and Cs pump beams were first theoretically investigated using a kinetic model for an end-pumped dual-wavelength Rb-Cs laser. Then, a continuous-wave (CW) laser was experimentally constructed. Finally, the hybrid CW-modulated output with two wavelengths was also successfully obtained for the first time in development of alkali lasers. The results might be helpful in applications for laser communication and ranging/radar in the future.

18.
J Hazard Mater ; 358: 337-345, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30005245

RESUMO

Novel ternary nanohybrids, consisting of tetraethylenepentamine (TEPA), graphene oxide (GO) and manganese ferrite magnetic nanoparticles (TEPA-GO/MnFe2O4), were prepared by a facile hydrothermal method and utilized to remove Pb(II) from aqueous solution effectively. The adsorbents were characterized by SEM, TEM, XRD, FTIR, zeta potential analysis, magnetization hysteresis loop, BET and XPS. These nanoparticles exhibited superparamagnetic behavior as well as high removal efficiency for Pb(II). Moreover, numerous amino groups of the functionalized pendant TEPA on GO coupled with the porous structure of TEPA-GO/MnFe2O4 contribute to high Pb(II) adsorption capacity. The maximum Pb(II) adsorption capacity of TEPA-GO/MnFe2O4 was determined to be 263.2 mg/g at the optimized solution pH of 5.5, much higher than that of GO/MnFe2O4 (133.3 mg/g) and GO (196.1 mg/g). The kinetics and isotherm data fitted well with the pseudo-second-order kinetics and the Langmuir isotherm model, respectively. Thermodynamic studies revealed that the Pb(II) adsorption of TEPA-GO/MnFe2O4 was a endothermic and spontaneous process. The experimental results corroborated that TEPA-GO/MnFe2O4 can be efficaciously reused after washed with HCl, indicative of its potential applications in environmental cleanup.

19.
Food Funct ; 9(5): 2673-2683, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29675530

RESUMO

Gentianaceae herb extracts have been widely used as food additives, teas or medicinal remedies for various diseases and disorders of the human body. Herein, the potential effects of iridoids, seco-iridoids and analog glycosides from gentian on acontine-induced hepatotoxicity were investigated in HepG2 cells to obtain metabolic data of drug-biotarget interactions. Molecular docking analysis was performed to assess the binding efficiencies of 53 iridoids, seco-iridoids and analog compounds obtained from 50 gentian species to the active sites of human CYP3A4 enzyme. The docking scores of 29 iridoids, seco-iridoids and 24 analog glycosides were calculated from the free energy of ligand-protein complexes using a computer-assisted docking simulation. After comprehensive evaluation, 6 of these compounds, i.e., gentiopicroside, sweroside, swertiamarin, loganic acid, 6-O-ß-d-glucosyl-gentiopicroside and amarogentin were selected to evaluate their hepatoprotective effects. Quantitative real-time PCR was used to measure the expression levels of CYP3A4 mRNA in HepG2 cells. Amarogentin displayed the most clear inductive effect on CYP3A4 mRNA levels in the HepG2 cells. Moreover, amarogentin was further studied for acontine-induced toxicity in the HepG2 cells to determine the potential mechanisms. Amarogentin displayed obvious inductive effect on CYP3A4 mRNA levels in the HepG2 cells. These results elucidated that the hepatoprotective effects were caused by the facilitation of drug metabolism, amelioration of mitochondrial dysfunction and reduction of oxidative stress. Our data demonstrated that the naturally found iridoids, seco-iridoids and analog glycosides in gentian may be responsible for the hepatoprotective effects of gentian-extracted compounds and thus, this study may be useful in the food industry or in clinical practice.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Gentianaceae/química , Glicosídeos/farmacologia , Iridoides/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Citocromo P-450 CYP3A/genética , Glicosídeos/química , Células Hep G2 , Humanos , Iridoides/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Substâncias Protetoras/química
20.
RSC Adv ; 8(44): 24993-25000, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35542164

RESUMO

Covalently-functionalized graphene oxide (FGO) was successfully prepared by grafting a novel phosphorus-containing flame retardant, [2-((6-oxidodibenzo[c,e][1,2]oxaphosphinin-6-yl)methoxy)acryloxyethylchlorophosphate, PACP], to graphene oxide (GO). The resulting FGO demonstrated hydrophobicity and stability in polar solvents such as N,N-dimethylformamide (DMF). The reactive vinyl groups of PACP attached to FGO further copolymerized with styrene to produce polystyrene-FGO (PS-FGO) nanocomposites. PS-FGO samples showed obviously improved fire-resistance, thermal behavior and glass transition temperature in comparison with those of neat PS and PS-GO samples, due to the good dispersion of FGO in PS as well as the strong interfacial bonds between FGO and the matrix. In addition, thermogravimetry-Fourier transform infrared (TG-FTIR) results indicated that the evolution of volatile products from PS decomposition was significantly inhibited by the introduction of FGO. Furthermore, scanning electron microscopy (SEM) and FTIR and Raman spectroscopy were employed to investigate the char residue, elaborating the flame-retardance mechanism.

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