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1.
Am J Respir Cell Mol Biol ; 62(1): 49-60, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31211918

RESUMO

For decades, stem cell therapies for pulmonary hypertension (PH) have progressed from laboratory hypothesis to clinical practice. Promising preclinical investigations have laid both a theoretical and practical foundation for clinical application of mesenchymal stem cells (MSCs) for PH therapy. However, the underlying mechanisms are still poorly understood. We sought to study the effects and mechanisms of MSCs on the treatment of PH. For in vivo experiments, the transplanted GFP+ MSCs were traced at different time points in the lung tissue of a chronic hypoxia-induced PH (CHPH) rat model. The effects of MSCs on PH pathogenesis were evaluated in both CHPH and sugen hypoxia-induced PH models. For in vitro experiments, primary pulmonary microvascular endothelial cells were cultured and treated with the MSC conditioned medium. The specific markers of endothelial-to-mesenchymal transition (EndMT) and cell migration properties were measured. MSCs decreased pulmonary arterial pressure and ameliorated the collagen deposition, and reduced the thickening and muscularization in both CHPH and sugen hypoxia-induced PH rat models. Then, MSCs significantly attenuated the hypoxia-induced EndMT in both the lungs of PH models and primary cultured rat pulmonary microvascular endothelial cells, as reflected by increased mesenchymal cell markers (fibronectin 1 and vimentin) and decreased endothelial cell markers (vascular endothelial cadherin and platelet endothelial cell adhesion molecule-1). Moreover, MSCs also markedly inhibited the protein expression and degradation of hypoxia-inducible factor-2α, which is known to trigger EndMT progression. Our data suggest that MSCs successfully prevent PH by ameliorating pulmonary vascular remodeling, inflammation, and EndMT. Transplantation of MSCs could potentially be a powerful therapeutic approach against PH.

2.
Aging (Albany NY) ; 11(24): 11844-11864, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31881011

RESUMO

Hydrogen sulfide (H2S), an endogenous gaseous signal molecule, regulates many pathologies related to aging. Sirtuin 1 (SIRT1) has been shown to protect against mitochondrial dysfunction and other pathological processes, including premature senescence. This study was aimed to investigate whether and how H2S attenuates senescence and apoptosis of alveolar epithelial cells via a SIRT1-dependent mechanism. Our results showed that treatment with sodium hydrosulfide (NaHS), a donor of H2S, attenuated cigarette smoke extract (CSE)-induced oxidative stress, mitochondrial dysfunction, cellular senescence and apoptosis in A549 cells. This was associated with SIRT1 upregulation. SIRT1 activation by a pharmacological activator, SRT1720, attenuated CSE-induced oxidative stress and mitochondrial dysfunction in A549 cells. While SIRT1 inhibition by EX 527 or silencing by siRNA transfection significantly attenuated or abolished the ability of NaHS to reverse the CSE-induced oxidative stress, mitochondrial dysfunction and the imbalance of mitochondrial fusion and fission. Also, SIRT1 inhibition or silencing abolished the protection of NaHS against CSE-induced cellular senescence and apoptosis. In conclusion, H2S attenuates CSE-induced cellular senescence and apoptosis by improving mitochondrial function and reducing oxidative stress in alveolar epithelial cells in a SIRT1-dependent manner. These findings provide novel mechanisms underlying the protection of H2S against cigarette smoke-induced COPD.

3.
Int Immunopharmacol ; : 105979, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31771816

RESUMO

Chronic obstructive pulmonary fibrosis (COPD) is a chronic and fatal lung disease with few treatment options. Sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), was found to alleviate cigarette smoke (CS)-induced emphysema in mice, however, the underlying mechanisms have not yet been clarified. In this study, we investigated its effects on COPD in a CS-induced mouse model in vivo and in cigarette smoke extract (CSE)-stimulated alveolar epithelial A549 cells in vitro. The results showed that NaHS not only relieved emphysema, but also improved pulmonary function in CS-exposed mice. NaHS significantly increased the expressions of tight junction proteins (i.e., ZO-1, Occludin and claudin-1), and reduced apoptosis and secretion of pro-inflammatory cytokines (i.e., TNF-α, IL-6 and IL-1ß) in CS-exposed mouse lungs and CSE-incubated A549 cells, indicating H2S inhibits CS-induced inflammation, injury and apoptosis in alveolar epithelial cells. NaHS also upregulated prolyl hydroxylase (PHD)2, and suppressed hypoxia-inducible factor (HIF)-1α expression in vivo and in vitro, suggesting H2S inhibits CS-induced activation of PHD2/HIF-1α axis. Moreover, NaHS inhibited CS-induced phosphorylation of ERK, JNK and p38 MAPK in vivo and in vitro, and treatment with their inhibitors reversed CSE-induced ZO-1 expression and inflammation in A549 cells. These results suggest that NaHS may prevent emphysema via the suppression of PHD2/HIF-1α/MAPK signaling pathway, and subsequently inhibition of inflammation, epithelial cell injury and apoptosis, and may be a novel strategy for the treatment of COPD.

4.
Int J Pharm ; 572: 118731, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31669213

RESUMO

Most pathogens enter the body through mucosal surfaces. Therefore, vaccination through the mucosal route can greatly enhance the mucosal immune response. Vaccination via the mucosal surface is the most effective way to trigger a protective mucosal immune response, but the vast majority of vaccines used are administered by injection. Strategies to enhance the mucosal immunity have been developed by using vaccine adjuvants, delivery systems, bacterial or viral vectors, and DNA vaccines. Appropriate vaccine adjuvants and drug delivery systems can improve the immunogenicity of antigens, induce a stronger immune response, and reduce the vaccine dose and production cost. In recent years, many studies have focused on finding safe and effective vaccine adjuvants and drug delivery systems to formulate the mucosal vaccines for solving the above problems. Great progress has also been made in vaccine adjuvants and drug delivery systems based on biodegradable polymer nanoparticles. In this paper, the research progress of the mucosal vaccine and its related adjuvants and drug delivery systems in recent years was reviewed, and the application of polymers as adjuvants and drug delivery system in vaccine was prospected. This review provides a fundamental knowledge for the application of biodegradable polymer nanoparticles as adjuvants and carriers in mucosal vaccines and shows great application prospects.

5.
Sci Rep ; 9(1): 13210, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519970

RESUMO

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease that is associated with the destruction of immune tolerance and activation of B cells. Interleukin (IL)-35 and IL-35-producing (IL-35+) regulatory B cells (Bregs) have been demonstrated to possess immunosuppressive functions, but their roles in the initiation and early development of SLE have not been explored. Here, we measured and compared the frequencies of blood regulatory B cell subsets and the concentrations of plasma IL-35, IL-10, IL-17A, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ in 47 Chinese patients with newly diagnosed SLE and 20 matched healthy controls (HCs). The SLE patients had decreased percentages of IL-35+ B cells and IL-10+ B cells among the total blood B cells as well as decreased concentrations of plasma IL-35. In addition, higher levels of plasma IL-10, IFN-γ, TNF-α, and IL-17 along with higher frequencies of circulating plasma and memory B cells were observed in the SLE patients. The percentage of IL-35+ Bregs and the serum IL-35 level were inversely correlated with the SLE disease activity index and the erythrocyte sedimentation rate (ESR) levels. Our results indicate that IL-35+ Bregs and IL-35 may play protective roles in SLE initiation and progression.

6.
Langmuir ; 35(42): 13663-13670, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31549513

RESUMO

Cellulose nanocrystals (CNCs) with excellent biodegradability are promising biomaterials for use as responsive Pickering emulsifiers. However, the high hydrophilicity of CNCs limits their emulsification ability. Some existing studies have utilized complicated covalent modification procedures to increase the hydrophobicity of CNCs. To simplify the modification process, we prepared hydrophobically modified CNCs (CNCs-M2005) via simple and controllable electrostatic interactions with thermosensitive M2005. The obtained CNCs-M2005 exhibited temperature and CO2 dual-responsive properties. Subsequently, stable oil/water Pickering emulsions were prepared using the partially hydrophobic CNCs-M2005 at 20 °C. However, demulsification occurred when the temperature increased to 60 °C. This temperature-induced demulsification resulted from the dehydration of polyethylene oxide and polypropylene oxide, causing the aggregation of the CNCs-M2005, as shown by dynamic light scattering and transmission electron microscopy experiments. In addition, demulsification was also achieved after bubbling CO2, which was attributed to the dissociation of the partially hydrophobic CNCs-M2005. The temperature and CO2 dual-responsive biosafe Pickering emulsions open up opportunity for the design of intelligent food, cosmetic, and drug delivery systems.

7.
J Colloid Interface Sci ; 557: 185-195, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521968

RESUMO

HYPOTHESIS: One of the major challenges in applying CO2-responsive surfactants concerns their tunable switchability and robustness under operating conditions. We hypothesize that combining monoethanolamine (MEA) with long-chain fatty acids (LCFAs) of variable chain lengths through electrostatic attraction could develop a series of CO2-responsive surfactants with tunable switching pH. EXPERIMENTS: The tunability of switching pH for this group of surfactants was demonstrated by in situ probing of the CO2-responsive characteristics at the oil/water interface using dynamic interfacial tension (IFT) measurements. Two protocols were applied to distinguish interfacial response and solution response. The key importance of interfacial response was demonstrated by two essential applications of CO2-responsive surfactants: demulsification of stable emulsions, and alternation of the interfacial properties of ultra-heavy crude oil-water interfaces. FINDINGS: The switching pH of the CO2-responsive surfactants was controlled by the hydrocarbon chain length of LCFAs. More importantly, their switching behaviour was found to be different at the interface and in the bulk solution, which is attributed to the enhanced molecular interactions at the interface. Since most applications require surfactants to be switched at the interface, it is thereby most appropriate to determine the switching pH through their interfacial responses.

8.
J Colloid Interface Sci ; 555: 53-63, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31376768

RESUMO

HYPOTHESIS: High temperatures can reduce the colloidal stability and rheological properties of nonpolar organoclay suspensions. The desorption of surfactants from organoclay has been proposed to explain this effect, but the mechanism remains unclear. In this work, it was hypothesized that the high-temperature-induced desorption of ion-exchanged surfactants is the main factor affecting the stabilization of suspensions. EXPERIMENTS: Using the cationic surfactant dimethyldioctadecylammonium chloride (DODMAC) and Na-montmorillonite (Na-MMT), the high-temperature-induced reestablishment of the adsorption-desorption equilibrium of DODMAC in organoclay suspensions was studied. Thermogravimetric analysis combined with infrared spectroscopy and gas chromatography/mass spectrometry experiments were performed to determine the thermal decomposition products and, ultimately, infer the adsorption modes and locations of DODMAC on Na-MMT. Thermal analysis and rheology were utilized to demonstrate the high-temperature-induced desorption and transfer of DODMAC in organoclay suspensions. FINDINGS: High temperatures induced the complete desorption of physically adsorbed DODMAC molecules from particle surfaces, the partial desorption of ion-exchanged dimethyldioctadecylammonium ions (DODMA+ ions) from particle surfaces, and the partial transfer of ion-exchanged DODMA+ ions from the surfaces to the interlayers. Importantly, desorption of ion-exchanged DODMA+ ions resulted in destabilization of the organoclay suspensions at high temperatures.

9.
Life Sci ; 232: 116650, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302196

RESUMO

BACKGROUND: Inhalation of NO2 leads to a progressive airflow limitation and the development of emphysema-like lesions. We report on the efficacy of hydrogen sulfide (NaHS) for alleviating NO2-induced pulmonary impairment. METHODS: Sprague Dawley rats were exposed to 20 ppm NO2 for 6 h over six consecutive days for 75 days. At day 75, rats who had developed NO2-induced emphysema were then divided into sodium hydrosulfide (NaHS) administrated group, placebo (NaCl) group and spontaneous recovery group for about one month (days 76-105); Pulmonary function (PF) and hematological and biochemical indices were measured at days 14, 45, 75, and 105. RESULTS: NO2 exposure for 75 days was associated with a significant decrease in FEV100/FVC%, an increased in functional residual capacity (FRC), and histologic evidence of emphysema, moreover; NO2 exposure led to elevated triglyceride (TG), red blood cell (RBC), hemoglobin (HGB), and hematocrit (HCT) levels. Impaired rats treated with NaHS showed no further deterioration in PF compared to rats exposed to ambient air and elevated WBC, granulocyte and lymphocyte counts and HDL-C levels to rats given NaCl. CONCLUSIONS: NO2 exposure causes emphysema and a decline in PF in rats. NaHS could alleviate the PF decline as possible indicated by an elevation of HDL-C levels and leukocyte. NaHS has therapeutic potential for emphysema caused by air pollutant NO2.


Assuntos
Testes Hematológicos , Pulmão/efeitos dos fármacos , Dióxido de Nitrogênio/toxicidade , Sulfetos/administração & dosagem , Sulfetos/farmacologia , Administração por Inalação , Animais , Pulmão/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Testes de Função Respiratória
10.
Med Sci Monit ; 25: 4193-4201, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31166938

RESUMO

BACKGROUND The prognosis of idiopathic pulmonary fibrosis (IPF) is the worst among all interstitial lung diseases, and is related to the disease itself. Comorbidities or complications can worsen IPF. We assessed the effect of comorbidities on the survival of IPF patients. A retrospective review of patients with IPF was completed. MATERIAL AND METHODS Information on demographic features, clinical examination, and comorbidities at baseline were obtained. Then, median, 1-year, and 5-year survival was calculated. A total of 380 patients with IPF admitted to Beijing Chao-Yang Hospital from 1 April 2002 to 31 March 2015 were followed up until December 2016. RESULTS Of these 380 patients, 71.9% died during the study period. Median survival was 2.25 years and overall 5-year survival was 28.5%. Also, 86.3% of patients were males. A total of 248 cases underwent lung function tests, and 178 patients underwent bronchoalveolar lavage (BAL). Multivariate analyses showed that forced expiratory volume in 1 second/forced vital capacity (FVC), diffusing capacity of the lungs for carbon monoxide percent predicted, FVC% predicted, the number of macrophages, neutrophils, and lymphocytes in BAL fluid, pulmonary hypertension, hypoxemia, and hydropower disorder were independent prognostic indicators of IPF, GAP gender (G), age (A), and 2 pulmonary physiological parameters (P) model can help to predict prognosis of IPF. CONCLUSIONS Spirometry, GAP model, and BAL are helpful to forecast the prognosis of IPF. IPF patients also suffering from pulmonary arterial hypertension, hypoxemia, and hydropower disorder have a poor prognosis.


Assuntos
Fibrose Pulmonar Idiopática/mortalidade , Fibrose Pulmonar Idiopática/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Lavagem Broncoalveolar , Líquido da Lavagem Broncoalveolar , China , Comorbidade , Feminino , Volume Expiratório Forçado , Humanos , Hipertensão Pulmonar/patologia , Fibrose Pulmonar Idiopática/diagnóstico , Pulmão/patologia , Doenças Pulmonares Intersticiais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Testes de Função Respiratória , Estudos Retrospectivos , Análise de Sobrevida , Volume de Ventilação Pulmonar , Capacidade Vital
11.
Sci Rep ; 9(1): 7398, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31068652

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

12.
J Phys Chem B ; 123(14): 3096-3102, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30883124

RESUMO

Binary mixtures of water and organic solvents are described as the aqueous solutions of organic solvents, which are usually spatially heterogeneous on the scale of a few molecular sizes but homogeneous on longer length scales, that is, microheterogeneity. For the water-organic solvent binary mixtures with microheterogeneity, most organic solvents are miscible with water at any ratio. Interestingly, some slightly water-miscible organic solvents can also be used to prepare binary mixtures with microheterogeneity. In this study, N, N-dimethylcyclohexylamine (DMCHA) was used to prepare binary mixtures with microheterogeneity and CO2 switchability. With the help of conductivity, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and dynamic light scattering measurements, we found that water molecules are hydrogen-bonded together to form clusters over the water content range of 9 to 27 wt %, exhibiting microheterogeneity in the binary mixture. The size of the water clusters increases slightly with increasing water content. What is more, the DMCHA-water mixtures can be reversibly split into two phases by alternate bubbling of CO2 and N2, exhibiting excellent CO2 switchability. The binary mixtures can be used as reaction media for the synthesis of CaCO3 nanoparticles. Binary mixtures with microheterogeneity can also be formed under high salinity or high temperature conditions or be prepared using other slightly water-miscible organic solvents, opening up more interesting possibilities for binary mixtures with microheterogeneity.

13.
J Colloid Interface Sci ; 540: 177-184, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30640065

RESUMO

HYPOTHESIS: Surfactants with temperature-sensitive polyoxyethylene (POE) chains are widely used to prepare nanoemulsions by the phase inversion temperature (PIT) method. It is therefore anticipated that surfactants with temperature-sensitive polyoxypropylene (POP) chains could also be used to prepare nanoemulsions by the PIT method. EXPERIMENT: POP surfactants were synthesized through electrostatic interactions between hydrophilic POP diamines and hydrophobic long-chain fatty acids. The synthesized POP surfactants were used as emulsifiers to prepare n-tetradecane-in-water nanoemulsions by the PIT method. Electrical conductivity measurements were used to determine the PITs of the water/POP surfactant/n-tetradecane systems. The effects of surfactant concentration, NaCl concentration, number of POP units, and degree of unsaturation of hydrocarbon chains on the PIT and the nanoemulsion droplet size were investigated. The droplet size and morphology of the nanoemulsions were characterized by dynamic light scattering and cryogenic transmission electron microscopy, respectively. FINDINGS: Nanoemulsions are formed by the PIT method using POP surfactants when the POP chains are short (∼2.5-6.1 POP units). The formation of nanoemulsions with droplet radii of 20-300 nm and spherical morphology occurs because of the temperature-dependent hydration of the short POP chains.

14.
J Colloid Interface Sci ; 536: 381-388, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30380437

RESUMO

HYPOTHESIS: To obtain surfactants with superior surface activity and responsive behavior, "pseudogemini" surfactants (short for D-LCFA) are synthesized by mixing long chain fatty acids (LCFA) and polyetheramine D 230 at fixed molar ratio (2:1). Non-covalently bonded building blocks indicate that CO2-responsive aqueous foams can be obtained by utilizing such pseudogemini surfactants. EXPERIMENTS: 1H NMR and FT-IR characterizations prove that the building blocks of these surfactants are associated by electrostatic interaction. The synthesis (Brønsted acid-base reaction) is simple and eco-friendly. "Pseudogemini" structure enables D-LCFA to reduce surface tension of aqueous solution effectively, thus facilitating foam generation. Rheograms, FF-TEM and Cryo-TEM results prove that different aggregates in D-LCFA aqueous solutions lead to different foam properties. FINDINGS: Bubbling of CO2 for about 30 s leads to the rupture of aqueous foams generated by D-LCFA, while removing CO2 by bubbling of N2 at 65 °C for 10 min enables re-generation of foams. The CO2-responsive foaming properties can be attributed to dissociation of D-LCFA upon bubbling of CO2 and re-association upon removal of CO2. The effective CO2-responsive foams can be applied to many areas, such as foam fracturing, foam enhanced oil recovery or recovering of radioactive materials.

15.
J Colloid Interface Sci ; 534: 595-604, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30265987

RESUMO

A CO2-responsive superamphiphile was designed to form switchable O/W microemulsions of rapid switching responses. The linear structured superamphiphile was assembled via electrostatic interactions between anionic oleic acid and cationic Jeffamine D-230 at a mole ratio of 1:1. Addition of the CO2-responsive superamphiphile and 1-butanol as a co-surfactant led to the spontaneous formation of stable heptane-in-water microemulsions. Treating this stable microemulsion with CO2 for 20 s caused dissociation of the superamphiphile into interfacial inactive components, leading to a complete phase separation of the microemulsion into immiscible oil and water phases. Removing the CO2 from the system by N2 sparging at 60 °C for 10 min converted the phase-separated system into a transparent microemulsion as a result of the in situ formation of the superamphiphile. Compared with the results from previous studies, the O/W microemulsion formed using the current superamphiphile with the co-addition of 1-butanol featured not only a unique thermodynamical stability of nano-sized droplets, but also a desired response to CO2 to achieve a rapid and complete phase separation, and re-microemulsification as desired with N2 sparging, making this CO2-responsive O/W microemulsion a promising candidate for applications such as nanomaterial synthesis, enhanced oil recovery and soil remediation.

16.
Int J Biometeorol ; 63(2): 159-166, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30565077

RESUMO

The current study investigated the correlation between stroke mortality and temperature. Monthly and seasonal variations in stroke mortality were plotted and daily stroke-related deaths were calculated. The lag times were calculated using the time series analysis. The correlation between stroke incidence and the diurnal temperature range (DTR) was analyzed using case-crossover analysis. Global stroke mortality was described in five latitudes. In the eastern region of Inner Mongolia, the stroke mortality was 174.18/105, about twice of that of the midwestern regions (87.07/105), and temperature was negatively correlated with stroke mortality. Mortality peaked in the winter and troughed in the summer (χ2 = 13.634, P < 0.001). The days in which stroke-related deaths were greater than ten occurred between late October and early April. The effect of temperature on stroke incidence occurred during a lag time of 1 (P = 0.024) or 2 months (P = 0.039). A DTR over 13 °C was positively correlated (r = 0.95, P = 0.004) with stroke with a lag time of 1 day. The effect of temperature on stroke was shown to be the same for various populations. As the latitude increases, stroke mortality also increases with latitudes > 40°; the highest mortality was 188.05/105 at the highest latitude. Only in relatively cold regions as the temperature decreases does stroke mortality increase for various populations. Differences in the time lag as well as in the DTR lag and DTR critical point vary for both the temperature and region.


Assuntos
Acidente Vascular Cerebral/mortalidade , Temperatura Ambiente , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Sci Rep ; 8(1): 15397, 2018 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-30337616

RESUMO

By utilizing the synergistic effect of chitosan (CS), magnetite (Fe3O4) particles, and graphene oxide (GO), a series of efficient and eco-friendly chitosan/magnetite-graphene oxide (CS/MGO) composites were fabricated through a facile chemical route. First, Fe3O4 particles were chemically deposited on the surface of GO to fabricate MGO hybrid. Then, chitosan was attached on MGO sheets, assembling to CS/MGO composites. According to the results of characterization, the covalent Fe-O-C bonds, electrostatic attraction, and hydrogen bonding between GO, Fe3O4, and chitosan ensure excellent structural stability and physico-chemical properties. The adsorption of Cr(VI) onto CS/MGO composites was also carried out under various conditions (content of CS, pH, initial concentration, contact time, and temperature). The CS/MGO composites possess high removal capacity for Cr(VI) from aqueous solution. Moreover, results also suggested that the CS/MGO composites had a strong reducing action for Cr(VI). When adsorption occurred, Cr(VI) and Cr(III) were simultaneously removed by CS/MGO composites. In addition, CS/MGO composites could retain good Cr(VI) removal efficiency after reuse over five cycles. CS/MGO composites are expected to have potential applications as easily regenerative bioadsorbents for Cr(VI) polluted water cleanup.


Assuntos
Quitosana/química , Cromo/isolamento & purificação , Óxido Ferroso-Férrico/química , Grafite/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Cromo/análise , Cromo/toxicidade , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
18.
Sci Rep ; 8(1): 9989, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29968784

RESUMO

A numerical technique of high-order piecewise parabolic method in combination of HLLD ("D" denotes Discontinuities) Riemann solver is developed for the numerical simulation of elastic-plastic flow. The introduction of the plastic effect is realized by decomposing the total deformation gradient tensor as the product of elastic and plastic deformation gradient tensors and adding plastic source term to the conservation law model equation with the variable of the elastic deformation gradient tensor. For the solution of the resulting inhomogeneous equation system, a temporal splitting strategy is adopted and a semi-implicit scheme is performed to solve the ODES in the plastic step, which is conducted to account for the contributions from plastic source terms. As seen from the results of test cases involving large deformation and high strain rate, the computational model used can reflect the characteristics of constitutive relation of material under strong impact action and our numerical method can realize the exact simulation of the elastic-plastic behavior of solid material, especially the accurate capture of the elastic-plastic waves. Further, it could also deal with high-speed impact problems with multi-material components, catching material interfaces correctly and keeping the interfaces sharp, when combined with interface tracking technique such as the level-set algorithm.

19.
Soft Matter ; 14(19): 3889-3901, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29726876

RESUMO

Emulsions were prepared using hydroxyapatite nanoparticles and nonionic surfactant sorbitan monooleate (Span 80) as emulsifier. Effects of Span 80 concentration, emulsification time, emulsification rate, poly(l-lactic acid) (PLLA) concentration and the surface chemical properties of hydroxyapatite nanoparticles on emulsion properties were systematically studied. The results showed that emulsion would undergo a phase inversion from oil-in-water (O/W) type to water-in-oil (W/O) type with an increase in Span 80 concentration. All of the above factors are closely related to emulsion type and stability. SEM results indicated that cured materials with different structures were obtained using these emulsions as templates via in situ evaporation; especially, open-cell porous structures were obtained by a mixture of hydroxyapatite and a moderate concentration of Span 80. The mechanism of this emulsion system is proposed in relation to the emulsion properties and cured material structure, which should be attributed to the formation of hydrogen bonds between hydroxyapatite and Span 80 by hydroxyl groups as well as their location changes in the emulsion.

20.
Sci Rep ; 8(1): 7609, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29765063

RESUMO

Long non-coding RNAs (lncRNAs) have critical regulatory roles in protein-coding gene expression. Aberrant expression profiles of lncRNAs have been observed in various human diseases. In this study, we investigated transcriptome profiles in lung tissues of chronic cigarette smoke (CS)-induced COPD mouse model. We found that 109 lncRNAs and 260 mRNAs were significantly differential expressed in lungs of chronic CS-induced COPD mouse model compared with control animals. GO and KEGG analyses indicated that differentially expressed lncRNAs associated protein-coding genes were mainly involved in protein processing of endoplasmic reticulum pathway, and taurine and hypotaurine metabolism pathway. The combination of high throughput data analysis and the results of qRT-PCR validation in lungs of chronic CS-induced COPD mouse model, 16HBE cells with CSE treatment and PBMC from patients with COPD revealed that NR_102714 and its associated protein-coding gene UCHL1 might be involved in the development of COPD both in mouse and human. In conclusion, our study demonstrated that aberrant expression profiles of lncRNAs and mRNAs existed in lungs of chronic CS-induced COPD mouse model. From animal models perspective, these results might provide further clues to investigate biological functions of lncRNAs and their potential target protein-coding genes in the pathogenesis of COPD.


Assuntos
Perfilação da Expressão Gênica/métodos , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , RNA Longo não Codificante/genética , Produtos do Tabaco/efeitos adversos , Ubiquitina Tiolesterase/genética , Células A549 , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Pulmão/química , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Doença Pulmonar Obstrutiva Crônica/genética , Análise de Sequência de RNA
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