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1.
Sci Total Environ ; 926: 172024, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547989

RESUMO

The use of reclaimed water for urban river replenishment has raised concerns regarding its impact on water quality and aquatic ecosystems. This study aims to reveal the improvements seen in an urban river undergoing a practical water eco-remediation after being replenished with reclaimed water. A one-year monitoring of water quality, phytoplankton, and zooplankton was carried out in Dongsha River undergoing eco-remediation in Beijing, China. The results showed that compared to the unrestored river, the concentrations of COD, NH4+-N, TP, and TN decreased by 28.22 ± 7.88 %, 40.24 ± 11.77 %, 44.17 ± 17.29 %, and 28.66 ± 10.39 % in the restoration project area, respectively. The concentration of Chlorophyll-a in the restoration area was maintained below 40 µg/L. During summer, when algal growth is vigorous, the density of Cyanophyta in the unrestored river decreased from 46.84 × 104cells/L to 16.32 × 104cells/L in the restored area, while that of Chlorophyta decreased from 41.61 × 104cells/L to 11.87 × 104cells/L, a reduction of 65.16 % and 71.47 %, respectively. The dominant phytoplankton species were replaced with Bacillariophyta, such as Synedra sp. and Nitzschia sp., indicating that the restoration of aquatic plants reduces the risk of Cyanophyta blooms. Zooplankton species also changed in the restoration area, especially during summer. The density of pollution-tolerant Rotifer and Protozoa decreased by 31.06 % and 27.22 %, while the density of clean water indicating Cladocera increased by 101.19 %. We further calculated the diversity and evenness index of phytoplankton and zooplankton within and outside the restoration area. The results showed that the Shannon-Weaver index for phytoplankton and zooplankton in the restoration area was 2.1 and 1.91, which was higher than those in the river (1.84 and 1.82). This further confirmed that aquatic plant restoration has positive effects. This study can provide a practical reference and theoretical basis for the implementation of water ecological restoration projects in other reclaimed water rivers in China.


Assuntos
Cianobactérias , Diatomáceas , Animais , Qualidade da Água , Pequim , Ecossistema , Rios , China , Fitoplâncton , Zooplâncton , Monitoramento Ambiental
2.
Carbohydr Polym ; 331: 121853, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388035

RESUMO

Stability of displacement front is of great importance in the immiscible fluid displacement for enhancing oil recovery. Here, a CO2-strenghened assembly approach is demonstrated for the fabrication of highly jammed CNSs (cellulose nanocrystal surfactants) with EPD (N'-ethylpropane-1,3-diamine) and TOCNC (TEMPO oxidized cellulose nanocrystal), which produce a structured film at the oil-water interface to counteract the capillary force, and thus governing the local displacing pattern. In this approach, EPD molecules can be deeply protonated in the presence of CO2, favoring their binding forces with TOCNC at the interface to produce more CNSs. Meanwhile, the strong intermolecular attractions among CO2-bearing CNSs promote to form a striped interfacial film with both the close-packed rod-like arrays in horizontal and the multi-layer in lateral. Further, the CNSs-based film confers with a high strength and elasticity can reduce the capillary force by 87 % in micro-channels, yielding a smooth water-to-oil displacement front, which markedly enhances the oil recovery by 20.6 % compared to the surfactant-only flooding. This self-assembly strategy has a great implication in eco-friendly and cost-effective applications, such as enhanced oil recovery, CO2 geo-sequestration, and water infiltration.

3.
Drug Dev Ind Pharm ; 49(9): 551-558, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37647269

RESUMO

OBJECTIVES: Sub-visible particle, or particulate matter, is an important indicator in the safety assessment of clinical infusions. The present study aims to evaluate the effect of the packaging formats of antibiotic on the distribution of sub-visible particles in the small particle size range (<10 µm), to provide evidence for explanation to clinical adverse reactions and guidelines for rational drug use. METHODS: The conventional light blockage and the single particle optical sensing (SPOS) technology were applied to determine the size distribution of the sub-visible particles in the redissolved injections in different packages (dual-chamber bag and vial) from different manufacturers. In order to verify our hypothesis, the influences of active pharmaceutical ingredient (API) and solvent were controlled. Further, scanning electron microscopy (SEM) was utilized to observe the morphological characteristics of sub-visible particles from different package injections. RESULTS: After redissolving, the small-sized sub-visible particles (<10 µm) in the solution of injectable powder packaged in the dual-chamber bag were significantly lower than that of the conventional injectable powder packaged in the vial, and the difference remained significant after controlling for API. The results observed by SEM also supported the differences in the amount of particulate matter between the two packaging formats, showing a higher number of sub-visible particles from sodium chloride dissolved preparations packed in vails, with irregular shapes. CONCLUSION: In our study, the differences in the distribution of sub-visible particles were mainly attributed to the packaging formats. The dual-chamber bag injection might be an effective alternative to reduce the adverse reactions caused by sub-visible particles.


Assuntos
Embalagem de Medicamentos , Material Particulado , Pós , Tamanho da Partícula , Injeções
4.
ACS Appl Mater Interfaces ; 15(33): 39883-39895, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37578297

RESUMO

Hydrogels have been widely applied to the water shutoff in oilfields due to their excellent three-dimensional network and thermal and physicochemical stability, and it is still a huge challenge to develop new hydrogels with simple preparation, low cost, and high mechanical performance that can meet the requirements of practical applications. Herein, we devised a simple and universal manufacturing method for regulating the hydrogen bonds between poly(vinyl alcohol) (PVA) and cellulose nanofibers (CNF) via the water-diffusion action, thus fabricating a physically tough PVA-CNF hydrogel for the in situ water shutoff. This method allowed the polymer chains to strengthen the molecular interactions between polymers upon replacing with water (a poor solvent) to regulate the cross-linking structure, characterizing by the nano-crystallinity domains and fibrillar segments, which also accounted for the thermal stability, extraordinary elasticity, high stretchability, and toughness of PVA-CNF hydrogel. Further, the obtained PVA-CNF hydrogel exhibited superb plugging performance, that is, the breakthrough pressure gradient could reach 71.56 MPa·m-1, surpassing all currently reported gelling water shutoff agents. This water-induced in situ hydrogelation made it well suited as a water shutoff agent in oilfields and may provide a promising strategy to fabricate mechanically robust smart materials for the water shutoff projects with low cost, simple processing, and high efficiency.

5.
ACS Omega ; 8(28): 25134-25141, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483196

RESUMO

Catalysts are an important factor in reducing harsh reaction conditions and increasing oil yields for the cohydrogenation of coal-oil. In this article, nano-iron-based catalysts have been prepared by mechanical solid-phase ball milling with FeCl3·6H2O, Fe(NO3)3·9H2O, and ammonium carbonate as reactants. The catalysts were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. With these catalysts, cohydrogenation behaviors of coal-oil have been carried out with Hami Baishihu coal and Karamay petrochemical coking residual oil under conditions of 400 °C, initial pressure of 7 MPa, and reaction time of 1 h. The results showed that the coal conversion rate reached 98.45% and the oil yield reached 77.73% when the catalyst prepared with FeCl3·6H2O as an iron source was added. Compared with research results reported in the literature, under the same conditions, the catalyst prepared in this article showed better catalytic activity in the cohydrogenation of coal-petrochemical coking residual oil.

6.
ACS Omega ; 8(21): 18400-18407, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273628

RESUMO

With the growing demand for gasoline and diesel fuel and the shortage of conventional oil reserves, there has been extensive interest in upgrading technologies for unconventional feedstocks such as heavy oil. Slurry bed reactors with high tolerance to heavy oil have been extensively investigated. Among them, dispersive MoS2 is favored for its excellent hydrogenation ability for heavy oil even under harsh reaction conditions such as high pressure and high temperature, its ability to effectively prevent damage to equipment from deposited coke, and its ability to meet the requirement of high catalyst dispersion for slurry bed reactors. This paper reviews the relationship between the structure and hydrogenation effectiveness of dispersive molybdenum disulfide, the hydrogenation mechanism, and the improvement of its hydrogenation performance by adding defects and compares the application of molybdenum disulfide in heavy oil hydrogenation, desulfurization, deoxygenation, and denitrification. It is found that the current research on dispersive molybdenum disulfide catalysts focuses mostly on the reduction of stacking layers and catalytic performance, and there is a lack of research on the lateral dimensions, microdomain regions, and defect sites of MoS2 catalysts. The relationship between catalyst structure and hydrogenation effect also lags far behind the application of MoS2 in the precipitation of hydrogen, etc. Oil-soluble and water-soluble MoS2 catalysts eventually need to be converted to a solid sulfide state to have hydrogenation activity. The conversion history of soluble catalysts to solid-type catalysts and the key to their improved catalytic effectiveness remain unclear.

7.
Materials (Basel) ; 16(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37241241

RESUMO

Porous carbon nanofibers are commonly used for adsorption processes owing to their high specific surface area and rich pore structure. However, the poor mechanical properties of polyacrylonitrile (PAN)-based porous carbon nanofibers have limited their applications. Herein, we introduced solid waste-derived oxidized coal liquefaction residue (OCLR) into PAN-based nanofibers to obtain activated reinforced porous carbon nanofibers (ARCNF) with enhanced mechanical properties and regeneration for efficient adsorption of organic dyes in wastewater. This study examined the effects of contact time, concentration, temperature, pH, and salinity on the adsorption capacity. The adsorption processes of the dyes in ARCNF are appropriately described by the pseudo-second-order kinetic model. The maximum adsorption capacity for malachite green (MG) on ARCNF is 2712.84 mg g-1 according to the fitted parameters of the Langmuir model. Adsorption thermodynamics indicated that the adsorptions of the five dyes are spontaneous and endothermic processes. In addition, ARCNF have good regenerative performance, and the adsorption capacity of MG is still higher than 76% after 5 adsorption-desorption cycles. Our prepared ARCNF can efficiently adsorb organic dyes in wastewater, reducing the pollution to the environment and providing a new idea for solid waste recycling and water treatment.

8.
Carbohydr Polym ; 311: 120759, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37028878

RESUMO

The injection of CO2 into oil reservoirs to enhance oil recovery (EOR) has become a widely accepted and effective technical method, which, however, remains subject to the gas channeling caused by the reservoir fractures. Herein, this work developed a novel plugging gel combining excellent mechanical properties, fatigue resistance, elastic and self-healing properties for the CO2 shutoff purpose. This gel consisting of grafted nanocellulose and polymer network was synthesized via a free-radical polymerization, and reinforced by using Fe3+ to cross-link the two networks. The as-prepared PAA-TOCNF-Fe3+ gel has a stress of 1.03 MPa and a high strain of 1491 %, and self-heals to its original 98 % in stress and 96 % in strain after rupture, respectively. The introduce of TOCNF/Fe3+ improves the excellent energy dissipation and self-healing via the synergy effect of dynamical coordination bonds and hydrogen bonds. Further, the PAA-TOCNF-Fe3+ gel is both flexible and high-strength in plugging the multi-round CO2 injection, during which the CO2 breakthrough pressure is above 9.9 MPa/m, the plugging efficiency exceeds 96 %, and the self-healing rate is larger than 90 %. Given that above, this gel shows a great potential to plug the high-pressure CO2 flow, which could offer a new method for CO2-EOR and carbon storage.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36883961

RESUMO

Polymer gels can be effectively applied to plug fractured reservoirs and carbonate cave strata. Herein, polyvinyl alcohol (PVA), acrylamide, and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) were used as raw materials to prepare interpenetrating three-dimensional network polymer gels using formation saltwater in the Tahe oilfield (Tarim Basin, NW China) as a solvent. The effect of AMPS concentration on the gelation properties of PVA in high-temperature formation saltwater was analyzed. Further, the effect of PVA concentration on the strength and viscoelastic properties of polymer gel was studied. The polymer gel could retain stable continuous entanglement at 130 °C and exhibited satisfactory thermal stability. Continuous step oscillation frequency tests showed that it exhibited an excellent self-healing performance. Scanning electron microscopy images of the simulated core by gel plugging showed that the polymer gel could firmly fill the porous media, indicating that the polymer gel exhibits excellent application prospects in oil and gas reservoirs under high-temperature and high-salinity conditions.

10.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36232661

RESUMO

The adsorption separation and extraction of low-concentration boron from salt-lake brine have great significance. Magnetic separation avoids the problem of adsorbent granulation and improves the usage efficiency. The silicon-based adsorbents have attracted interest due to their superior acid and alkali resistance, in which polyhydroxy graphene enhances the adsorption of boron ions. Herein different boron adsorbents, derived by magnetic separation, were developed and characterized by SEM, TEM, XPS, VSM, FT-IR, and XRD analysis. The adsorption-desorption performance of boron adsorbents with different compositions was evaluated. The isotherms and kinetics parameters of the boron extraction were evaluated based on adsorption-desorption tests. The graphene-based magnetic adsorbent (Go-Fe3O4@SiO2@mSiO2-Glu) registered a high boron adsorption capacity of 23.90 mg/g at pH = 9 in the boron solution and 24.84 mg/g for East Taigener salt-lake brine. The Na+, Mg2+, Ca2+, and Cl- ions have little interference with the boron adsorption. The adsorbents exhibit magnetic separation performance and good cycle life. The results showed that acid-alkali desorption solution has little effect on the adsorbents, and the composite of graphene enhances the adsorption of boron ions. The adsorbents developed in this study are promising to recover boron from low-concentration boron-containing salt-lake brines.


Assuntos
Grafite , Poluentes Químicos da Água , Adsorção , Álcalis , Boro , Glucose , Grafite/química , Cetoácidos , Lagos , Fenômenos Magnéticos , Sais , Silício , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Int J Anal Chem ; 2022: 6734408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992562

RESUMO

In this work, a UPLC-MS/MS method was developed for the determination of gypenoside A and gypenoside XLIX in rat plasma. For chromatographic separation, a UPLC BEH C18 column was employed, the mobile phase comprised acetonitrile: water (w/0.1% formic acid), and the elution time was 4 min. Detection of each compound was enabled by electrospray ionization in negative-ion mode, and quantitative analysis was enabled by operating in multiple reaction monitoring (MRM) mode by monitoring the transitions of m/z 897.5⟶403.3 for gypenoside A, m/z 1045.5⟶118.9 for gypenoside XLIX, and m/z 825.4⟶617.5 for the internal standard. The calibration curves for gypenoside A and gypenoside XLIX demonstrated excellent linearity (r > 0.995) over the range of 2-3000 ng/mL. The intraday and interday precisions of gypenoside A and gypenoside XLIX were within 14.9%, the intraday and interday accuracies ranged from 90.1% to 113.9%, the recoveries were all greater than 88.3%, and the matrix effect ranged from 87.1% to 94.1%. The developed method was successfully applied in the determination of the pharmacokinetics of gypenoside A and gypenoside XLIX. Gypenoside A and gypenoside XLIX had very short half-lives in rats, with oral t 1/2z of 1.4 ± 0.2 h and 1.8 ± 0.6 h, respectively, and low bioavailabilities (0.90% and 0.14%, respectively).

12.
ACS Appl Mater Interfaces ; 14(32): 37134-37148, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35917120

RESUMO

CO2 foams are of great importance in oil recovery but challenging in some aspects like long-term stabilization and time-separated conflict. In this work, a stability-enhanced switchable foam was fabricated using bis-(2-hydroxyethoxy) olefine amine (BOA) and trace amounts (0.05 wt %) of cationic-modified cellulose nanofibers (CCNFs). The CCNF was developed using sequentially functionalized CNF with diamine groups, which were essential to promote the aqueous dispersibility and a key for strengthening the stabilization of foam. The combination of similarly charged CCNFs and BOA in the presence of CO2 contributed to both surface activity and viscoelasticity. It was demonstrated that CCNFs were entangled and stacked to form the compact films and possessed the ability to costabilize the lamellae, as observed by microscopic studies. In addition, the intermolecular H-bonds were promoted in the binary system after being protonated by CO2 and thus balancing the electrostatic forces, as explored by spectroscopy characterizations. The soft fibrous structure of the CCNF was also capable of wrapping gas bubbles in the form of a functional membrane with both low gas permeability and high surface potential, which slowed down the coarsening and coalescence. Of particular interest is that the reversible protonation state of CCNF-BOA complexes upon the alternate treatment with CO2/N2 led to reversible fast foaming/defoaming, which would be beneficial to construct the steerable plugging in the sand pack. This work is expected to provide a new direction and application of the CO2 responsive foam stabilized by similarly charged nanocellulose fibers in oilfield development.

13.
Biomed Chromatogr ; 36(9): e5419, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35638105

RESUMO

This study developed a UPLC-MS/MS method to detect isoscoparin in mouse blood, determined the pharmacokinetics of isoscoparin in mice after intravenous (5 mg/kg) and intragastric (20 mg/kg) administration, and calculated the absolute bioavailability. A HSS T3 column was used for separation, and the column temperature was set at 40°C. The mobile phases were acetonitrile and 0.1% formic acid, and the gradient elution procedure was used. The blood sample was treated with protein precipitant with acetonitrile-methanol (9:1, v/v). Multiple reaction monitoring mode was used for quantitative analysis in electrospray positive-ion mode. It showed a good linear relationship in the range of 1-4000 ng/mL (r > 0.998); the intra-day and inter-day precision was <12%, and the accuracy was 86-112%. The recovery was >68%, and the matrix effect was 86-90%. The half-life of isoscoparin was relatively short in mice, and the bioavailability was 2.6%. The developed UPLC-MS/MS method was rapid, sensitive, and suitable for the pharmacokinetics of isoscoparin in mice.


Assuntos
Espectrometria de Massas em Tandem , Acetonitrilas , Animais , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Camundongos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
14.
Chem Commun (Camb) ; 58(30): 4723-4726, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35302560

RESUMO

Smart ultra-stable foams stabilized by cellulose nanocrystal (CNC)-based gels were fabricated. The stabilization is ascribed to the dense films and three-dimensional networks at the interface and in the bulk induced by the charge shielding effect and electrostatic attraction between protonated bis(2-hydroxyethyl)oleylamine (BOA-H+) micelles and negatively charged CNC colloids. The as-prepared foam could maintain its morphology without breaking or drainage for two months, showing high stability. Outstanding CO2/N2 reversibility endows the system with on-demand control of foaming/defoaming, which is necessary in many aspects. The functionalized foam is expected to open up an opportunity for the design of intelligent oilfield chemicals and extinguishant systems.


Assuntos
Celulose , Nanopartículas , Celulose/química , Géis/química , Micelas , Nanopartículas/química
15.
Angew Chem Int Ed Engl ; 61(15): e202116404, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35156284

RESUMO

Heat-induced blueshift (HIB) observed in many luminescent materials is a puzzling phenomenon that has remained unexplained for decades. By using the high-throughput first-principles calculations and energy-screening techniques, we generated a number of model structures for five phosphors, RbLi[Li3 SiO4 ]2 :Eu2+ , Na[Li3 SiO4 ]:Eu2+ , K[Li3 SiO4 ]:Eu2+ , Sr[LiAl3 N4 ]:Eu2+ , and Ca[LiAl3 N4 ]:Eu2+ . Our analyses suggest, to a first approximation, a logarithmic energy dependence on the nearest distance between the dopant and the metal-cation vacancy. By identifying the 5 d → 4 f transition energies from the electronic structures calculated for the screened model structures, we show that the vibration of the Eu2+ ion lying in an asymmetric and anharmonic potential well couples with the electronic states, leading to their HIB phenomena.

16.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669030

RESUMO

Potato tuber dormancy is critical for the post-harvest quality. Snakin/Gibberellic Acid Stimulated in Arabidopsis (GASA) family genes are involved in the plants' defense against pathogens and in growth and development, but the effect of Snakin-2 (SN2) on tuber dormancy and sprouting is largely unknown. In this study, a transgenic approach was applied to manipulate the expression level of SN2 in tubers, and it demonstrated that StSN2 significantly controlled tuber sprouting, and silencing StSN2 resulted in a release of dormancy and overexpressing tubers showed a longer dormant period than that of the control. Further analyses revealed that the decrease expression level accelerated skin cracking and water loss. Metabolite analyses revealed that StSN2 significantly down-regulated the accumulation of lignin precursors in the periderm, and the change of lignin content was documented, a finding which was consistent with the precursors' level. Subsequently, proteomics found that cinnamyl alcohol dehydrogenase (CAD), caffeic acid O-methyltransferase (COMT) and peroxidase (Prx), the key proteins for lignin synthesis, were significantly up-regulated in silencing lines, and gene expression and enzyme activity analyses also supported this effect. Interestingly, we found that StSN2 physically interacts with three peroxidases catalyzing the oxidation and polymerization of lignin. In addition, SN2 altered the hydrogen peroxide (H2O2) content and the activities of superoxide dismutase (SOD) and catalase (CAT). These results suggest that StSN2 negatively regulates lignin biosynthesis and H2O2 accumulation, and ultimately inhibits the sprouting of potato tubers.


Assuntos
Cisteína/metabolismo , Peróxido de Hidrogênio/metabolismo , Lignina/biossíntese , Proteínas de Plantas/metabolismo , Tubérculos/metabolismo , Solanum tuberosum/metabolismo , Oxirredutases do Álcool/metabolismo , Catalase/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica , Lignina/metabolismo , Peroxidase/metabolismo , Dormência de Plantas/genética , Proteínas de Plantas/genética , Caules de Planta/citologia , Caules de Planta/genética , Caules de Planta/metabolismo , Tubérculos/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Ligação Proteica , Proteína O-Metiltransferase/metabolismo , Proteômica , Plântula/citologia , Plântula/genética , Plântula/metabolismo , Solanum tuberosum/enzimologia , Solanum tuberosum/genética , Superóxido Dismutase-1/metabolismo
17.
Nat Prod Res ; 35(1): 25-33, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31135216

RESUMO

Two new compounds, including a diterpenoid glycoside (1) and a triterpenoid glycoside (6), along with six known compounds were isolated from Clinopodium chinense. The structures of the new compounds were determined on basis of extensive spectral analysis and chemical method. Compounds 1-8 were evaluated for their insulin resistance effect and cytotoxic activity against the A549 and HepG2 cancer cell lines. None of the compounds were cytotoxic (IC50 > 100 µM), while compounds 1-3 and 5 showed the activity of ameliorating insulin resistance in HepG2.


Assuntos
Diterpenos/farmacologia , Lamiaceae/química , Triterpenos/farmacologia , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/química , Avaliação Pré-Clínica de Medicamentos , Glicosídeos/química , Glicosídeos/farmacologia , Células Hep G2 , Humanos , Resistência à Insulina , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Triterpenos/química
18.
Food Nutr Res ; 642020.
Artigo em Inglês | MEDLINE | ID: mdl-33061882

RESUMO

BACKGROUND: Diabetic cardiomyopathy (DCM) is a serious complication of diabetes that can lead to significant mortality. Cyclocarya paliurus is a tree, the leaves of which are often utilized to prevent and treat diabetes mellitus. Whether C. paliurus leaves can prevent or treat DCM, however, it remains to be formally assessed. The present study was therefore designed to assess the ability of C. paliurus to protect against DCM in db/db mice. METHODS: Male wild-type (WT) and db/db mice were administered C. paliurus ethanol leaf extracts (ECL) or appropriate vehicle controls daily via gavage, and levels of blood glucose in treated animals were assessed on a weekly basis. After a 10-week treatment, the levels of cardiac troponin I (cTn-I), lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), aspartate transaminase (AST), total triglycerides (TG), and total cholesterol (TC) in serum were measured. Activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) and the levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-6 in heart tissues were detected. Hematoxylin-eosin (HE) and Masson staining were conducted. The protein expression that related with oxidative stress and inflammatory reaction was evaluated by Western blotting. RESULTS: Compared with WT mice, the TG, TC, and blood glucose levels in db/db mice increased significantly, which were reduced by ECL treatment. Compared with WT mice, the levels of LDH, CK-MB, AST, and cTn-I in serum and MDA in heart tissues of db/db mice increased significantly. Activities of SOD, GSH-Px, and CAT in heart tissues of db/db mice decreased significantly. The levels of inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in heart tissues of db/db mice increased remarkably. However, ECL treatment improved the above pathological changes significantly. ECL alleviated pathological injury and fibrosis in heart tissues of mice. Western blotting showed that ECL increased Bcl-2 level and decreased Bax, cle-caspase-3, and cle-caspase-9 expression. Furthermore, ECL inhibited NF-κB nuclear translocation and increased PI3K and p-Akt expressions. CONCLUSION: Our results indicate that ECL treatment can markedly reduce pathological cardiac damage in db/db mice through antiapoptotic, antifibrotic, and anti-inflammatory mechanisms. Specifically, this extract was able to suppress NF-κB activation via the PI3K/Akt signaling pathway. Given its diverse activities and lack of significant side effects, ECL may thus have therapeutic value for the treatment of DCM.

19.
J Mol Model ; 26(10): 257, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32886185

RESUMO

Basing on the simplest hydrothermal system containing deionized water, hexa-ammonium molybdate, and thiourea, hydrothermal mechanism on preparation of MoS2 was studied by DFT calculation. Hydrothermal process was divided into four steps which covered ionization equilibrium, the hydrolysis of CS(NH2)2, the formation of intermediates, and the formation of MoS2. Ionization equilibrium occurs at normal condition and determines the existence of Mo in the form of molybdic acid. Thiourea hydrolysis is rate-determining step in the process of hydrothermal which contains 10 elementary reactions. The formation of intermediates includes hydrogen transfer, dehydration, and vulcanization three steps which contain 18 elementary reactions, and the energy barrier of vulcanization is the highest. The formation of MoS2 is divided into two steps, the first step is that MoO(OH)(SH)3.H2O reacts with MoO (SH)4.H2O to form layer MoS2, and the second step is a very fast process that can affect the morphology of the products.

20.
Sci Total Environ ; 749: 141487, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32829274

RESUMO

Adsorption plays an important role in seawater desalination, wastewater treatment, and, especially, boron removal from natural aqueous systems. In this paper, two sponge-like multifunctional polymers based on a cyclodextrin backbone were synthesized and used as adsorbents for the removal of boron, methylene blue (MB), methyl orange (MO), and phenol. The syntheses were carried out by esterification, atom transfer polymerization, and nucleophilic addition reaction. The polymers were characterized by 1H NMR spectroscopy, IR spectroscopy, XRD, XPS, and SEM. The performance of the two different adsorbents was investigated considering the effect of pH, initial concentration, and the anions and cations in an aqueous solution of borates. The experimental data were fitted with an adsorption isothermal model, adsorption kinetic model and other models. Both adsorbents exhibited high adsorption capacities (B: 31.05 mg/g and 20.45 mg/g, MB: 29.43 mg/g and 32.29 mg/g, MO: 47.36 mg/g and 49.23 mg/g, phenol: 5.04 mg/g and 4.35 mg/g, respectively) and a fast adsorption rate. The boron adsorption was found to be an exothermic process. The adsorbents show promising potential for the removal of boron and benzene-containing organic pollutants from aqueous solution.

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