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1.
Chemosphere ; 287(Pt 2): 132192, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34517240

RESUMO

The application of environmental-friendly and sustainable green materials in constructing photocatalysts to degrade pharmaceuticals and personal care products (PPCPs) attracts more attention. Herein, biochar (BC) or biomass carbon quantum dots (CQDs) were used to modify MgIn2S4/BiOCl (MB) heterojunction photocatalyst with Z-scheme structure, and improved the photocatalytic degradation performance for carbamazepine (CBZ) in the aqueous solution. Both BC and CQDs could form electron transfer interface with MB heterojunction, resulting in the photodegradation rate of MgIn2S4/BiOCl/CQDs (MBC, 96.43%) and MgIn2S4/BiOCl/BC (MBB, 88.09%) to CBZ within 120 min visible-light irradiation, which were significantly higher than that of MB (65.84%). Moreover, photoelectrochemical and photoluminescence tests verified that CQDs could act as a bridge for storing and transferring electrons in the entire Z-scheme system. Thence, compared with MBB, MBC could produce more •OH and •O2- under the visible light, which was indicated by the results of radical quenching experiments and electron paramagnetic resonance. Interestingly, under the natural sunlight, the photocatalytic performance of MBC to CBZ was even better than under laboratory conditions. In addition, the TOC removal efficiencies of MBB and MBC could reach 85.09% and 93.79% respectively, and ECOSAR program was utilized to further evaluate the eco-toxicity of CBZ and the intermediates towards fish, daphnid, and green algae, indicating that the photocatalytic process involving MBB and MBC showed outstanding toxicity reduction performance. Finally, compared with other composites, MBB and MBC showed higher photocatalytic performance and lower energy consumption, which would provide a green strategy for biochar materials in the photocatalytic treatment of PPCPs in water.

2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(7): 704-710, 2021 Jul 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34382586

RESUMO

OBJECTIVES: To investigate the risk factors for serious infections among hospitalized systemic lupus erythematosus (SLE) patients, and to provide the advice for preventing serious infections in SLE patients. METHODS: Information of SLE patients hospitalized from March 2017 to February 2019 at the Department of Rheumatology and Immunology, Xiangya Hospital, Central South University was obtained. The patients were assigned into a serious infection group and a non-serious infection group. The risk factors for serious infections among SLE inpatients were identified by comparison between the 2 groups and multivariate logistic regression analysis. RESULTS: There were 463 SLE inpatients in total, and 144 were in the serious infection group and 319 in the non-serious infection group. Multivariate logistic regression analysis showed that age ≥54.50 years old (OR=4.958, P<0.001), cardiovascular involvement (OR=6.287, P<0.001), hematologic involvement (OR=2.643, P=0.003), serum albumin <20 g/L (OR=2.340, P=0.036), C-reaction protein (CRP)/erythrocyte sedimentation rate (ESR)≥0.12 (OR=2.430, P=0.002), glucocorticoid dose ≥8.75 mg/d prednisone-equivalent (OR=2.465, P=0.002), and the combined use of immunosuppressive agents (OR=2.847, P=0.037) were the risk factors for serious infections in SLE inpatients. CONCLUSIONS: SLE patients with older age, cardiovascular involvement, hematologic involvement, low serum albumin are prone to suffering serious infections. Increased CRP/ESR ratio indicates serious infections in SLE inpatients. High-dose glucocorticoid and the combined use of immunosuppressive agents can increase the risk of serious infections in SLE inpatients.


Assuntos
Pacientes Internados , Lúpus Eritematoso Sistêmico , Idoso , Glucocorticoides/efeitos adversos , Humanos , Lúpus Eritematoso Sistêmico/complicações , Pessoa de Meia-Idade , Prednisona , Fatores de Risco
3.
Sci Total Environ ; 793: 148519, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171811

RESUMO

Direct Z-scheme heterojunctions composed of Ag2O nanoparticles and ZnO nanorods were immobilized on Ni foam (AZN) via combined hydrothermal and precipitation methods to successfully construct 3D reticulated composites, and their photocatalytic performance were evaluated under simulated sunlight. Just as expected, the AZN samples exhibited excellent photocatalytic effects of 99.26% for the model pollutant (rhodamine B) in water after loading with Ag2O, which was 2.77 times higher than that of regular ZnO NAs/Ni foam composites. Meanwhile, the surface wettability of composite was remarkably enhanced. Besides, a series of photoelectrochemical measurements showed a significant improvement in the charge separation efficiency of AZN, which was attributed to the synergistic effect of direct Z-scheme heterojunction, matched energy band structure as well as 3D porous structure. Moreover, the AZN sample presented satisfactory stability after four cycles, meanwhile it displayed good removal performance against different types of antibiotics (Tetracycline, Sulfadiazine and Ciprofloxacin). The applicability and durability of AZN for rhodamine B degradation were evaluated by sequential batch experiments in a homemade simulated flowing water device. More importantly, the lower value of electrical energy per order indicated the photocatalyst/simulated sunlight system was more energy efficient and effective. Accordingly, this work provided a new strategy for designing 3D reticulated composites with low-dimensional nanomaterials to decompose organic pollutants in impaired waters.


Assuntos
Óxido de Zinco , Antibacterianos , Catálise , Luz , Tetraciclina
4.
Am J Transl Res ; 13(3): 1170-1183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841647

RESUMO

Ischemic stroke is the main cause of disability and mortality in the world. Clinical studies have shown that patients who undergo mild transient ischemic attack (TIA) before more severe ischemic stroke have lower clinical severity of stroke and better functional prognosis. This phenomenon is called ischemic preconditioning (IPC). IPC is a powerful intrinsic protection of the brain against ischemic injury, but the underlying mechanism of IPC-mediated endogenous protection of the brain is not clear. METHODS: Using transcriptome method, we sequenced the serum of 3 stroke patients with progenitor TIA and 3 stroke patients without prodromal TIA. We explored the expression profiles of miRNAs and mRNAs in response to IPC, and predicted the regulatory pathway of IPC related genes and their expression in cerebral neurons. The methylation consistent expression of IPC-related gene ATP2B1 in blood and brain and alternative polyadenylate (APA) analysis were used to identify the pathway and molecular mechanism of endogenous neuroprotection of IPC. RESULTS: We found that the brain protective effect of IPC was related to platelet homeostasis and Ca2+ concentration. IPC-related gene ATP2B1 was highly expressed in γ-aminobutyric acid (GABA)-containing neurons in the brain. From the mechanism, we speculated that ATP2B1 was representative of the same methylation in blood and brain and was affected by alternative polyadenylation. CONCLUSION: We speculate that IPC can induce alternative polyadenylation of ATP2B1 and trigger the mechanism of brain endogenous neuroprotection by regulating the decrease of Ca2+ concentration in platelet homeostasis pathway and the activation of GABAB receptor.

5.
Healthcare (Basel) ; 9(2)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670719

RESUMO

In ECG applications, the correct recognition of R-peaks is extremely important for detecting abnormalities, such as arrhythmia and ventricular hypertrophy. In this work, a novel ECG enhancement and R-peak detection method based on window variability is presented, and abbreviated as SQRS. Firstly, the ECG signal corrupted by various high or low-frequency noises is denoised by moving-average filtering. Secondly, the window variance transform technique is used to enhance the QRS complex and suppress the other components in the ECG, such as P/T waves and noise. Finally, the signal, converted by window variance transform, is applied to generate the R-peaks candidates, and the decision rules, including amplitude and kurtosis adaptive thresholds, are applied to determine the R-peaks. A special squared window variance transform (SWVT) is proposed to measure the signal variability in a certain time window, and this technique reduces false detection rate caused by the various types of interference presented in ECG signals. For the MIT-BIH arrhythmia database, the sensitivity of R-peak detection can reach 99.6% using the proposed method.

6.
Sci Total Environ ; 764: 142879, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33129540

RESUMO

Bi2WO6 possesses good stability but poor photocatalytic activity under visible light. Herein, the coupling of Bi2WO6, Fe3O4 and biochar (Bi2WO6/Fe3O4/BC) was investigated to enhance the photocatalytic performance of Bi2WO6 through facile hydrothermal method, which almost completely degraded ofloxacin (OFL) and ciprofloxacin (CIP) within 30 min under energy-saving visible LED irradiation. The superior photocatalytic activity of Bi2WO6/Fe3O4/BC was ascribed to the stronger visible light adsorption capacity and the lower recombination of electron-hole pairs. O2- played a major role during the photocatalytic reaction. The characterization results suggested that the introduction of biochar avoided the agglomeration of Bi2WO6 microspheres and Fe3O4 nanoparticles, at the same time, the biochar participated in OFL and CIP photodegradation by consuming different oxygen-containing functional groups. In order to further evaluate the application potential of Bi2WO6/Fe3O4/BC, the effects of environment factors and the application in different actual water were carefully investigated. Various transformation products and the possible degradation pathways of OFL and CIP were analyzed based on high resolution mass spectrometry (HRMS) results, moreover, the toxicity evaluation results of Escherichia coli indicated these intermediates products were less toxic compared OFL and CIP. Overall, Bi2WO6/Fe3O4/BC can provide a potential way for the application of photocatalytic technology in ambient wastewater purification.


Assuntos
Ciprofloxacina , Ofloxacino , Carvão Vegetal , Luz
7.
Environ Sci Pollut Res Int ; 28(11): 13375-13393, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33184787

RESUMO

A large amount of biochar-derived dissolved organic matter (BDOM) will be released into the environment with biochars application into repairing soil/water, which may alter the fate and transport of contaminants. In this study, four DOM samples were extracted from cauliflower root biochar (CRBC), reed straw biochar (RSBC), corn stalks biochar (CSBC), and potato stalk biochar (PSBC). Excitation-emission matrix combined with parallel factor (EEM-PARAFAC) analysis, differential absorbance spectra (DAS), and two-dimensional correlation spectroscopy (2D-COS) analysis were applied to explore the complexation property of BDOM with metals. DAS showed sites heterogeneity within the DOM pool for metals complexing. Humic-like and fulvic-like substances were main fluorescent components identified by EEM-PARAFAC. 2D-COS analysis revealed that polysaccharides and aliphatic firstly responded to Pb(II) binding with CRBC-derived DOM and three other biochar-derived DOM, respectively. While aliphatic groups, aromatic N=O, and polysaccharides gave the fastest response to Cu(II) binding with CRBC, RSBC, and the other two biochar-derived DOM, respectively.


Assuntos
2,5-Dimetoxi-4-Metilanfetamina , Substâncias Húmicas , Carvão Vegetal , Análise Fatorial , Substâncias Húmicas/análise , Espectrometria de Fluorescência
8.
Environ Sci Pollut Res Int ; 27(36): 45435-45446, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32789636

RESUMO

In this study, the CuO/Cu2O/Cu-biochar composite (CBC) was fabricated by calcining Cu2+-loaded cauliflower root at 500 °C. The CBC displayed the higher specific surface area and total pore volume than raw biochar, which attributed to Cu2+ acting as a pore-forming agent in the synthesis process. The adsorption experiments indicated that CBC could remove 88.96% diclofenac and 93.02% carbamazepine, which was nearly double higher than the raw biochar. The film diffusion mainly controlled the adsorption rate. Meanwhile, the common adsorption mechanisms for two pollutants were deemed to hydrogen-bonding interaction, π-π interaction and micropore filling effect, and copper oxide particles providing more adsorption sites. In addition, the adsorption of diclofenac involved electrostatic attraction. Lastly, the higher adsorption capacity of carbamazepine than diclofenac on CBC was mainly attributed to two mechanisms: Lewis acid-base interaction enhancing the adsorption of carbamazepine and size exclusion effect reducing the adsorption of diclofenac. Therefore, the study provided a possible method that Cu-contaminated biomass converted to CuO/Cu2O/Cu-biochar, which could achieve win-win results.


Assuntos
Diclofenaco , Poluentes Químicos da Água , Adsorção , Carbamazepina , Carvão Vegetal , Cobre
9.
Water Sci Technol ; 81(9): 1972-1982, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32666950

RESUMO

This study evaluated the effects of temporary external voltage on the performance of two-chambered microbial fuel cells (MFC) that use nitrate wastewater as a substrate. Results indicate that the external voltage affected the performance of the MFC during their operation, and this effect remained even after the voltage was removed. The degradation efficiency of the chemical oxygen demand increased in the MFC under external voltages of 0.5, 0.8, and 1.1 V, and the optimal applied voltage was 1.1 V. Compared with the control group without external voltages, the MFC under a voltage of 1.1 V achieved higher current densities and efficiency of nitrate removal during their operation. The MFC with an applied voltage of 1.1 V also achieved the highest maximum power density of 2,035.08 mW/m3. The applied voltages of 0.5 and 0.8 V exerted a positive effect on the performance of the MFC. High-throughput sequencing was used to explore the anode and cathode biofilms. Results showed that the influence was highly associated with microbial community in bio-anode. The predominant functional family changed from Methanotrichaceae during start-up to Flavobacteriaceae in a steady phase.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes , Análise da Demanda Biológica de Oxigênio , Eletricidade , Eletrodos , Águas Residuárias
10.
Eur J Pharmacol ; 881: 173233, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32492379

RESUMO

Endothelial progenitor cells (EPCs) are important to tissue repair and regeneration especially after ischemic injury, and very heterogeneous in phenotypes and biological features. Reactive oxygen species are involved in regulating EPC number and function. N-acetylcysteine (NAC) inhibits ischemia-induced reactive oxygen species formation and promotes ischemic limb recovery. This study was to evaluate the effect of NAC on EPC subpopulations in bone marrow (BM) and blood in mice with limb ischemia. Limb ischemia was induced by femoral artery ligation in male C57BL/6 mice with or without NAC treatment. EPC subpopulations, intracellular reactive oxygen species production, cell proliferation and apoptosis in BM and blood cells were analyzed at baseline, day 3 (acute ischemia) and 21 (chronic) after ligation. c-Kit+/CD31+, Sca-1+/Flk-1+, CD34+/CD133+, and CD34+/Flk-1+ were used to define EPC subpopulations. Limb blood flow, function, muscle structure, and capillary density were evaluated with laser Doppler perfusion imaging, treadmill test, and immunohistochemistry, respectively, at day 3, 7, 14 and 21 post ischemia. Reactive oxygen species production in circulating and BM mononuclear cells and EPCs populations were significantly increased in BM and blood in mice with acute and chronic ischemia. NAC treatment effectively blocked ischemia-induced reactive oxygen species production in circulating and BM mononuclear cells, and selectively increased EPC population in circulation, not BM, with preserved proliferation in mice with chronic ischemia, and enhanced limb blood flow and function recovery, while preventing acute ischemia-induced increase in BM and circulating EPCs. These data demonstrated that NAC selectively enhanced circulating EPC population in mice with chronic limb ischemia.


Assuntos
Acetilcisteína/farmacologia , Indutores da Angiogênese/farmacologia , Antioxidantes/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Isquemia/tratamento farmacológico , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Membro Posterior , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Recuperação de Função Fisiológica
11.
Biomed Res Int ; 2020: 1308526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509845

RESUMO

The mammalian central nervous system (CNS) has a limited ability to renew the damaged cells after a brain or spinal cord injury whether it is nonhuman primates like monkeys or humans. Transplantation of neural stem cells (NSCs) is a potential therapy for CNS injuries due to their pluripotency and differentiation abilities. Cytokines play an important role in CNS development and repair of CNS injuries. However, the detailed cytokine signaling response in monkey neural stem cells is rarely studied. In our previous research, we isolated NSCs from the adult monkey brain and found the effects of cytokines on monkey NSCs. Now, we further analyzed the regulation mechanisms of cytokines to the proliferation of monkey NSCs such as bone morphogenic protein 4 (BMP4), BMP4/leukaemia inhibitory factor (LIF), or retinoic acid (RA)/Forskolin. The data showed that BMP4 inhibited cell proliferation to arrest, but it did not affect the stemness of NSCs. BMP4/LIF promoted the astrocyte-like differentiation of monkey NSCs, and RA/forskolin induced the neuronal differentiation of monkey NSCs. BMP4/LIF and RA/forskolin induced monkey NSC differentiation by regulating Notch signaling. These results provide some theoretical evidence for NSC therapy to brain or spinal cord injury in regenerative medicine.


Assuntos
Citocinas/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 4/farmacologia , Encéfalo/citologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Colforsina/farmacologia , Fator Inibidor de Leucemia/farmacologia , Macaca fascicularis , Masculino , Tretinoína/farmacologia
12.
J Hazard Mater ; 391: 121407, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32145925

RESUMO

In this work, a novel, economical and effective vessel-like biochar-based photocatalyst Bi2S3/BiOBr/BC was synthesized by a facile one-pot solvothermal method for the first time. A series of characterization analyses demonstrated the successful preparation of photocatalyst Bi2S3/BiOBr/BC. Furthermore, diclofenac (DCF) as the target contaminant was applied to elucidate the enhanced photocatalytic performance (93.65%, 40 min) under energy-saving visible LED light irradiation. Comparison experiments among different photocatalysts and photoelectrochemical tests results illustrated that excellent photocatalytic performance of Bi2S3/BiOBr/BC 10% might be attributed to the electrons transfer of biochar and higher charge separation efficiency of heterojunction structure. Besides, lower electrical energy per order value indicated photocatalyst/visible LED light system was more energy-saving. Proper photocatalyst dosage (0.6 g/L) and relatively acidic water environment (pH = 5.0) would be beneficial to DCF photodegrdation by Bi2S3/BiOBr/BC. Good reusability and stability of Bi2S3/BiOBr/BC were verified via five consecutive recycle experiments. Furthermore, the role of active species was determined through trapping experiments and O2- and h+ dominated the photodegradation reaction to mineralize DCF molecules. Eleven main intermediates and four possible photodegradation pathways were proposed by HRMS analysis. Accordingly, photocatalyst Bi2S3/BiOBr/BC would provide potential technical support for emerging pollutant removal in water matrix.


Assuntos
Anti-Inflamatórios não Esteroides/química , Bismuto/química , Carvão Vegetal/química , Diclofenaco/química , Sulfetos/química , Poluentes Químicos da Água/química , Catálise , Carvão Vegetal/efeitos da radiação , Técnicas Eletroquímicas , Luz , Processos Fotoquímicos , Sulfetos/efeitos da radiação
13.
Eur J Pharmacol ; 876: 173051, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32145325

RESUMO

Synthetic apolipoprotein A-I (apoA-I) mimetic peptide 5F exhibits anti-atherosclerotic ability with largely unknown mechanism(s). Bone marrow (BM)-derived endothelial progenitor cells (EPCs) play a critical role in vascular integrity and function. The objective of the present study was to evaluate the effect of 5F on endothelial differentiation of BM stem cells and related mechanisms. Murine BM multipotent adult progenitor cells (MAPCs) were induced to differentiate into endothelial cells in vitro with or without 5F. The expression of endothelial markers vWF, Flk-1 and CD31 was significantly increased in the cells treated with 5F with enhanced in vitro vascular tube formation and LDL uptake without significant changes on proliferation and stem cell maker Oct-4 expression. Phosphorylated ERK1/2, not Akt, was significantly increased in 5F-treated cells. Treatment of MAPCs with PD98059 or small interfering RNA against ERK2 substantially attenuated ERK1/2 phosphorylation, and effectively prevented 5F-induced enhancement of endothelial differentiation of MAPCs. In vivo studies revealed that 5F increased EPCs number in the BM in mice after acute hindlimb ischemia that was effectively prevented with PD98059 treatment. These data supported the conclusion that 5F promoted endothelial differentiation of MAPCs through activation of ERK1/2 signaling.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Transplante de Medula Óssea , Proliferação de Células/efeitos dos fármacos , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/genética , Fator 3 de Transcrição de Octâmero/genética , RNA Interferente Pequeno/genética , Ratos , Transfecção
14.
Pediatr Neonatol ; 61(3): 306-310, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144075

RESUMO

OBJECTIVE: The study aimed to evaluate the association between microbes in the lower respiratory tract (LRT) and the srisk for severe bronchopulmonary dysplasia (sBPD) in premature infants. METHODS: We conducted a retrospective, single-center study of preterm infants who were admitted to the neonatal intensive care unit (NICU) of Southern Medical University Affiliated Maternal & Child Health Hospital of Foshan, China, between January 2015 and December 2017. The microbes in the LRT were screened by using tracheobronchial aspirate fluid (TAF) culture. RESULTS: One hundred and fifty-five infants were included in the analysis. Among 155 infants, 41 were diagnosed with sBPD, and 114 were diagnosed without sBPD. There were significant differences between infants with and without sBPD in regard to birth weight (BW), gestational age (GA), the duration of endotracheal ventilation and supplemental oxygen. The incidence of retinopathy (ROP) and sepsis was higher in the sBPD infants than in the infants without sBPD. There was a difference in the detection rate of Gram-negative bacteria (GNB) between the two groups. Stenotrophomonas maltophilia and Klebsiella pneumoniae were mainly detected in TAF. CONCLUSIONS: The LRT microbes were different between infants with and without sBPD, and GNB is more frequently detected in sBPD infants.


Assuntos
Brônquios/microbiologia , Displasia Broncopulmonar/etiologia , Bactérias Gram-Negativas/isolamento & purificação , Traqueia/microbiologia , Displasia Broncopulmonar/microbiologia , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Retrospectivos
15.
Sci Total Environ ; 710: 136289, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923667

RESUMO

In this work, nanoscale zero-valent iron (NZVI) was synthesized via liquid phase reduction method with surfactant polyethylene glycol (PEG-4000) modified and supported onto zeolite to prepare PZ-NZVI composite. SEM-EDS, XPS, BET.etc. characterizations indicated that the sphere NZVI particles were loaded on the zeolite successfully and the aggregation was restrained. The adsorption performance of PZ-NZVI for norfloxacin (NOR) or ofloxacin (OFL), two typical fluoroquinolones (FQs), from water was conducted. The equilibrium studies were demonstrated using Langmuir, Freundlich, Temkin and Elovich isotherms and better agreement was attained with the Temkin model. Compared with NZVI and zeolite, PZ-NZVI had higher FQs removal efficiency, and the Langmuir maximum adsorption capacity was 54.67 mg g-1 (NOR) and 48.88 mg g-1 (OFL). The kinetic parameters displayed that two FQs adsorption onto PZ-NZVI followed pseudo-second-order kinetic model. The thermodynamic analysis suggested the adsorption process was spontaneous and exothermic. In addition, the adsorption tests were executed at different influence factors and the adsorbent PZ-NZVI was suitable for a wide pH range (4-10) with the FQs (10 mg L-1) removal efficiency above 90% in 1 h. Furthermore, it was found that PZ-NZVI can be effortlessly separated from mixed solutions using external magnetic field. Finally, the process of FQs adsorbed onto PZ-NZVI was attributed to the surface complexion (forming bidentate complexes), hydrophobic interaction, pore filling and electrostatic interaction.


Assuntos
Zeolitas/química , Adsorção , Antibacterianos , Fluoroquinolonas , Ferro , Polietilenoglicóis , Poluentes Químicos da Água
16.
Biomater Sci ; 8(1): 313-324, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31701966

RESUMO

Unhealable diabetic wounds and disabling scar formation in severe wounds need to be addressed with the help of multiple techniques. Here we put forward an idea to use exosomes loaded into a supporting scaffold to rebuild the vascular transportation system, which could solve hypoxia and infertility in these wounds. A highly efficient self-healing and biocompatible natural-based methylcellulose-chitosan hydrogel loaded with biological exosome nanoparticles has the appropriate strength and is made by an easy preparation process, and it eventually achieves the integrated structure needed for healing severe diabetic conditions. Hydrogels perform well in the cell proliferation and skin remodeling stages because of their three-dimensional porous structure, and self-healing and adhesion properties. Also, exosomes accumulated to an effective concentration for a period of time could induce proliferation, especially relating to vascular formation. After the overpass (vascular) has been constructed with the help of the base (hydrogel) and workers (exosomes), the society (skin) is reconstructed under a system of supply and regulation. The research results indicate that these novel complex hydrogels loaded with exosomes provide wide prospects for the healing of severe wounds.


Assuntos
Biopolímeros/farmacologia , Diabetes Mellitus Experimental/complicações , Exossomos/fisiologia , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis , Biopolímeros/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana , Diabetes Mellitus Experimental/genética , Hidrogéis/química , Metilcelulose , Camundongos , Nanopartículas , Neovascularização Fisiológica/efeitos dos fármacos , Receptores para Leptina/genética
17.
Sci Total Environ ; 688: 1205-1215, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31726551

RESUMO

As antibiotics are widely consumed, fluoroquinolones (FQs) behave to have huge hidden danger to human health. Various agricultural residues have potential to produce biochar rich in porous structure for adsorption of contaminants. In this study, potato leaves and stems were pyrolyzed at 500 °C under anoxic condition for biochar (BC) preparation. At the same conditions, magnetic biochar (MBC) and humic acid (HA) coated magnetic biochar (HAB) were also prepared. In particular, characterizations of HAB showed the extensive coating of HA on MBC surface and introducing more oxygen-containing groups, which may promote the adsorption capacity of biochar. Three typical FQs (ciprofloxacin (CIP), norfloxacin (NOR) and enrofloxacin (ENR)) were used as target contaminants to further investigate the adsorption property of HAB. Compared with BC and MBC, novel adsorbent HAB due to introduction of HA exhibited better FQs adsorption ability, and its maximum adsorption capacity for CIP, NOR and ENR were 1.80, 1.67 and 1.70 times higher than those of MBC and were 3.40, 2.88, 2.96 times higher than those of raw BC, respectively. Pseudo-second-order kinetic model and Langmuir isotherm model could describe the process of FQs adsorbed on HAB more appropriately, and thermodynamic results illustrated that the sorption process was spontaneous and endothermic. In addition, FQs adsorption by HAB was increased with initial solution pH from 3.0 to 10.0, while it was slightly decreased with ionic strength rising (0.001-0.1 M CaCl2). Combined with FTIR results, high FQs removal efficiency could be attributed to electrostatic, hydrophobic, H-bond and π-π EDA interactions.


Assuntos
Carvão Vegetal/química , Fluoroquinolonas/química , Substâncias Húmicas/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos , Antibacterianos
18.
Med Sci Monit ; 25: 6719-6726, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31493329

RESUMO

BACKGROUND Bariatric procedures such as left gastric artery ligation (LGAL) and sleeve gastrectomy (SG) have emerged as important procedures for treating morbid obesity. In this study, we compared the effects of LGAL vs. SG on obesity-induced adipose tissue macrophage infiltration and inflammation in diet-induced obese rats. MATERIAL AND METHODS Sprague-Dawley (SD) rats were fed a high-fat diet (HFD) for 16 weeks to induce obesity. SG, GLAL, or corresponding sham surgeries were performed in anesthetized rats. Inflammatory factor expression in serum and epididymal and retroperitoneal adipose tissues were analyzed 4 weeks after surgery. Macrophage infiltration and phenotype transformation were also assessed with Western blot analysis and immunofluorescence. RESULTS Both LGAL and SG strongly attenuated high-fat diet (HFD)-induced fat accumulation in retroperitoneal and epididymal tissues. The expressions of inflammatory cytokines such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1 were downregulated after LGAL and after SG by promoting activation of M2 macrophages, despite continued exposure to HFD. Furthermore, both LGAL and SG resulted in increased macrophage infiltration, but did not contribute to phenotype transformation of macrophages to M1. CONCLUSIONS LGAL and SG both reduced fat accumulation caused by HFD feeding. Therapies designed to ameliorate the inflammatory response by promoting activation of M2 macrophages may be valuable.


Assuntos
Tecido Adiposo/patologia , Dieta Hiperlipídica , Gastrectomia , Artéria Gástrica/ultraestrutura , Inflamação/patologia , Macrófagos/patologia , Obesidade/patologia , Animais , Epididimo/patologia , Mediadores da Inflamação/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Ligadura , Masculino , NF-kappa B/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais
19.
Adv Healthc Mater ; 8(20): e1900967, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31557404

RESUMO

Stem cells therapy is an effective treatment for critical limb ischemia diseases (CLI), but is limited to low cells retention and poor target release in severe ischemia tissues. Due to the notable feature of CLI, namely, the temperature of ischemia tissues decreases with the severity of the lesions, a thermoresponsive and reversible hydrogel based on methylcellulose-salt system encapsulating stem cells is facilely prepared and successfully achieved the goal of releasing stem cells in lower temperature areas. The investigations show that the thermogel presents notable biocompatibility, thermoresponsiveness, and cytoprotection. Furthermore, the combined transplantation of hydrogel and stem cells system effectively inhibits the fibrosis and muscular atrophy of lower limb ischemia, accelerates the recovery of lower limb blood flow, and promotes angiogenesis, indicating that the reversible thermogel can promote vascular repair by controlling the release of loaded stem cells in the treatment of CLI.


Assuntos
Biopolímeros/química , Extremidades/patologia , Hidrogéis/química , Isquemia/terapia , Transplante de Células-Tronco/instrumentação , Células-Tronco/citologia , Animais , Atrofia , Feminino , Fibrose , Células HEK293 , Humanos , Masculino , Metilcelulose/química , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neovascularização Patológica , Neovascularização Fisiológica , Perfusão , Gravidez , Prenhez , Reologia , Estresse Mecânico , Temperatura
20.
Sci Total Environ ; 695: 133800, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31421336

RESUMO

Three adsorbents, namely, original biochar (CLB), montmorillonite (MMT)-biochar composite (MBC), and magnetic MMT-biochar composite (MMBC) were successfully fabricated by one step pyrolysis of original cauliflower (Brassica oleracea L.) leaves, mixture of cauliflower leaves and MMT, and FeCl3-laden mixture of cauliflower leaves and MMT under limited oxygen atmosphere, respectively. The characterizations of samples indicated that substantial MMT mineral particles and Fe3O4 nanoparticle were dispersed on the surface of MMBC. Due to the introduction of Fe3O4, MMBC performed excellent magnetization property. The adsorption experiments of oxytetracycline (OTC) indicated that the maximum adsorption ability of MMBC was 58.85 mg·g-1, which was 2.63 times as large as CLB, also, larger than that of MBC. Meanwhile, pH, ionic strength, and humic acid (HA) performed slight effects for adsorption of OTC on MMBC. In addition, MMBC still removed 92% OTC after five regeneration cycles. Finally, primary mechanisms of OTC adsorption onto MMBC were attributed to hydrogen bonding and π-π reaction, and ion exchange reaction was considered to exist. Meanwhile, functional groups including Si-O-Al, Si-O-Si, Si-O, and Fe3O4 nanoparticles would provide extra binding sites for OTC adsorption. Therefore, MMBC had an obvious potential to apply into water purification as a reliable, low-cost, and environmentally friendly adsorbent.


Assuntos
Oxitetraciclina/análise , Pirólise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Bentonita/química , Carvão Vegetal/química , Magnetismo , Oxitetraciclina/química , Poluentes Químicos da Água/química
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