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2.
J Nanosci Nanotechnol ; 20(5): 3047-3052, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635647

RESUMO

The g-C3N4/BiPO4 composites have been successfully synthesized via a one-pot hydrothermal process, which can be used to degrade the organic dyes (rhodamine B and methylene blue) under simulated sunlight irradiation. X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra and Fourier transform infrared (FTIR) spectroscopy have been employed to characterize the samples. The g-C3N4/BiPO4 composites exhibited higher photocatalytic activity than pure BiPO4. And the optimum photocatalyst shows the outstanding photocatalytic activity, which exhibited 99.0% and 86.6% decolorization rate of RhB and MB, respectively.

3.
Food Chem ; 305: 125476, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525589

RESUMO

Octenylsuccinate quinoa starch (OSQS) granule that stabilized Pickering emulsion gel with different gel networks by modulating the oil volume fraction (Φ) was developed as a carrier for lutein. Pickering emulsion gels stabilized by OSQS were achieved at Φ values ranging from 30% to 60%. Increasing Φ progressively increased the droplet size, storage modulus, and apparent viscosity, resulting in the formation of gel-like structure. Confocal laser scanning microscopy showed that OSQS formed a densely packed layer at the oil/water interface, the degree of aggregation between droplets increased, and the gel network enhanced through droplet flocculation with increasing Φ. After 31 days of storage, the retention index of lutein in the emulsion gel could reach 55.38%, and the corresponding half-life times increased from 12 to 41 days. This study will be useful for designing starch-based Pickering emulsion gel with tunable gel network and desirable characteristics as delivery carrier of sensitive bioactive compounds.

4.
Opt Express ; 27(20): 28618-28628, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684610

RESUMO

Transparent conductive oxide (TCO) films showing epsilon near zero (ENZ) properties have attracted great research interest due to their unique property of electrically tunable permittivity. In this work, we report the effect of oxygen stoichiometry on the structure, optical and ENZ properties of indium tin oxide (ITO) films fabricated under different oxygen partial pressures. By using spectroscopic ellipsometry (SE) with fast data acquisition capabilities, we observed modulation of the material index and ENZ wavelength under electrostatic gating. Using a two-layer model based on Thomas-Fermi screening model and the Drude model, the optical constants and Drude parameters of the ITO thin films are determined during the gating process. The maximum carrier modulation amplitude ΔN of the accumulation layer is found to vary significantly depending on the oxygen stoichiometry. Under an electric field gate bias of 2.5 MV/cm, the largest ENZ wavelength modulation up to 27.9 nm at around 1550 nm is observed in ITO thin films deposited with oxygen partial pressure of P O 2 =10 Pa. Our work provides insights to the optical properties of ITO during electrostatic gating process for electro-optic modulators (EOMs) applications.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31679781

RESUMO

Alloy-/conversion-type metal oxides usually exhibit high theoretical lithium storage capacities but suffer from the large volume change induced electrode pulverization and the poor electric conductivity, which limit their practical applications. Hybrid/mixed metal oxides with different working mechanisms/potentials can display advantageous synergistic enhancement effect if delicate structure engineering is performed. Herein, atomically hybridized SnO2/Co3O4 nanocomposites with amorphous nature are successfully cast onto the porous N-doped carbon (denoted as NC) nanoflakes through facile pyrolysis of the tin (II) 2-ethylhexanoate (C16H30O4Sn) and cobalt (II) 2-ethylhexanoate (C16H30O4Co) mixture within NC nanoflakes in air at 300 °C for 1 h. The Sn/Co atomic ratio and the loading amount of SnO2/Co3O4 can be readily controlled, whose effect on lithium storage are investigated as anodes for lithium ion batteries (LIBs). Notably, SnO2/Co3O4@NC (RSn/Co = 1.25) nanoflakes exhibit the most excellent lithium storage properties, delivering a reversible capacity of 1450.3 mA h g-1 after 300 cycles at 200 mA g-1, which is much higher than that of the single metal oxide SnO2@NC and Co3O4@NC electrodes.

6.
Chem Commun (Camb) ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31690924

RESUMO

In this work, we have proposed a new strategy to expand the function of a protein. By taking a protease as an example, it can be engineered to make up the shortcoming of natural proteases, and thus it can efficiently and selectively hydrolyze a desired protein even in a complex biological fluid.

7.
Chem Commun (Camb) ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31696872

RESUMO

Cholesterol (CHOL) is an indispensable component of liposomes. Incorporation of 7-dehydrocholesterol (7-DHC) instead of CHOL can efficiently enhance the anticancer activity of photosensitizer-encapsulated liposomes upon irradiation, yielding an IC50 value about half of that of CHOL-based controls. The photo-oxidation of 7-DHC into its endoperoxide form by singlet oxygen may account for the enhanced therapeutic effect, realizing an efficient combination of photodynamic therapy (PDT) and photoactivated chemotherapy.

8.
J Ethnopharmacol ; : 112336, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31669102

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Aglaia odorata Lour. is a traditional Chinese medicinal plant possessing properties of improving blood circulation, and it is widely used in the treatment of dizziness, traumatic injuries and bruises. AIM OF STUDY: In this study, we are aimed to investigate the cerebral protection effect of the extracts from leaves of Aglaia odorata Lour. (ELA) and the potential mechanism in vivo and in vitro. MATERIALS AND METHODS: The therapeutic effect of ELA on ischemic cerebral stroke was measured on a middle cerebral artery occlusion (MCAO) rat model. Protective effect of ELA on oxygen-glucose deprivation/reperfusion (OGD/R)-induced PC12 cells was measured by MTT assay. The apoptotic cells were observed by Hoechst 33258 staining and acridine orange/ethidium bromide double staining assay. Mitochondria were observed by Mitotracker staining assay. The mitochondrial membrane potential was determined by JC-1 staining assay. Western blot was used to investigate the effects of ELA on apoptosis-related proteins. RESULTS: We showed that ELA was an effective neuroprotective agent. In vivo experiments, ELA exerted significant protective effect on MCAO model. TTC staining showed that ELA could reduce cerebral infarction area against MCAO insult. HE and Nissl's staining indicated that ELA could reverse the damage of cortex and hippocampus caused by MCAO. In vitro experiments, ELA showed significant protective effect on OGD/R-induced PC12 cells by reducing the number of apoptotic cells, increasing mitochondrial membrane potential, and reducing superoxide aggregation, further suppressing mitochondrial caspase-9/3 apoptosis pathway. Moreover, protective effect of ELA on mitochondrial function may be exerted by inhibiting p53/Puma signal pathway. CONCLUSION: Our results suggest that ELA exerts a marked neuroprotective effect against cerebral ischemia potentially via suppressing p53/Puma-mediated mitochondrial caspase-9/3 apoptosis pathway.

9.
Spinal Cord ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676870

RESUMO

STUDY DESIGN: Cross-sectional self-report assessment. Econometric modeling. OBJECTIVES: Identify the relationship of multiple pain indicators, prescription pain medication, nonprescription opioid use, and multiple indicators of quality employment among those with spinal cord injury (SCI). SETTING: Data were collected at a medical university in the Southeastern United States (US). METHODS: Participants included 4670 adults with traumatic SCI of at least one-year duration who were enrolled in a study of health and longevity. They were identified from three sources including a specialty hospital and two population-based state SCI surveillance systems. Econometric modeling was used for three outcome variables: employment status, hours per week spent working, and earnings. RESULTS: Several pain parameters were significantly related to multiple employment outcomes. Prescription medication to treat pain was associated with lower odds of employment, fewer hours working, and lower conditional earnings. Nonprescription opioid use was only related to fewer hours working. Painful days, number of painful conditions, and pain intensity were all related to employment outcomes, but the pattern varied by outcome. The number of painful conditions was most consistently related to employment. Multiple demographic, injury, and educational factors were related to employment, with better outcomes among those with less severe SCI and greater educational achievements. CONCLUSIONS: The presence of significant pain and use of either prescription pain medications or the use of nonprescription opioids may have a significant adverse effect on both the probability of employment and quality of employment. Rehabilitation and vocational professionals should routinely assess pain and associated medications in vocational and career planning.

10.
Pharmacol Rep ; 71(6): 1244-1252, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670061

RESUMO

BACKGROUND: Coumarin and 3,4-dihydroquinolinone nuclei are two heterocyclic rings that are important and widely exploited for the development of bioactive molecules. Here, we designed and synthesized a series of 3,4-dihydroquinolinone and coumarin derivatives (Compounds 8, 9, 11, 14, 15, 18-20, 23, 24 and 28 are new compounds) and studied their antidepressant activities. METHODS: Forced swimming test (FST) and tail suspension test (TST) were used to evaluate the antidepressant activity of the target compounds. The most active compound was used to evaluate the exploratory activity of the animals by the open-field test. 5-HT concentration was estimated to evaluate if the compound has an effect on the mouse brain, by using ELISA. A 5-HT1A binding assay was also performed. The biological activities of the compounds were verified by molecular docking studies. The physicochemical and pharmacokinetic properties of the target compounds were predicted by Discovery Studio and ChemBioDraw Ultra. RESULTS: Of all the compounds tested, compound 7 showed the best antidepressant activity, which decreased the immobility time by 65.52 s in FST. However, in the open-field test, compound 7 did not affect spontaneous activity. The results of 5-HT concentration estimation in vivo showed that compound 7 may have an effect on the mouse brain. Molecular docking results indicated that compound 7 showed significant interactions with residues at the 5-HT1A receptor using homology modeling. The results show that compound 7 exhibits good affinity for the 5-HT1A receptor. CONCLUSION: Coumarin and 3,4-dihydroquinolinone derivatives synthesized in this study have a significant antidepressant activity. These findings can be useful in the design and synthesis of novel antidepressants.

11.
Environ Int ; : 105000, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31699440

RESUMO

Inhalation from ambient air and cigarette smoke is a common route of human exposure to polycyclic aromatic hydrocarbons (PAHs). Little information is available regarding hepatotoxicities of inhaled PAHs so for. In this study, we evaluated the toxic effects of intratracheally instilled benzo[a]pyrene (B[a]P) on hepatic lipid metabolism of C57BL/6 mice at relevant environmental exposure levels by using two different mass-based lipidomics approaches. The results of mass spectrometry imaging analysis showed that both the abundance and spatial distribution of several lysophosphatidylcholine (LysoPC), phosphatidylcholine (PC) and sphingomyelin (SM) in the liver section were different and changed after inhalation exposure to B[a]P. Liquid chromatography coupled with mass spectrometry-based lipidomics analysis and multivariate statistical analysis found that B[a]P exposure markedly altered glycerophospholipids, glycerolipids, and fatty acid metabolism in the mouse liver, with increasing of triacylglycerol (TG), phosphatidylinositol (PI) and PC, and decreasing of LysoPCs phosphatidylethanolamines (PEs), lysophosphatidylethanolamine (LysoPEs), free fatty acids (FFAs) and eicosanoids. B[a]P-induced lipid metabolic disorders showed a time-dependent effect, which generated three response trajectories with different change trends. Consequently, B[a]P exposure induced alteration of hepatic lipids by promoting the uptake from blood or the biosynthesis and transformation in the liver, might contribute to non-alcoholic fatty liver disease, hepatocyte membrane injury, inflammation, and signal system disturbance.

12.
Cytotherapy ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31699595

RESUMO

Systemic chemotherapy is a conventional and important strategy for inhibition of cancer progression, but it is usually accompanied by various adverse effects. Targeting drug delivery systems, effective tools to avoid the adverse effects of chemotherapy, have been intensively studied and developed. Recently, the emerging application of exosomes and exosome-mimics (small extracellular vesicles [sEVs]) in targeted drug delivery and therapeutics has been widely appreciated. The sEVs-based delivery system comprises three basic components: vesicles, cargoes and surface decorations. In this article, we review the current status, existing challenges and future directions in this field from the following aspects: selection and production of vesicles; cargoes and methods to load them into vesicles; modifications to the surfaces of vesicles; as well as ways to prolong the half-life of sEVs in the circulation. Existing and emerging data indicate that sEVs are promising nanocarriers for clinical use, but additional efforts are needed to translate research findings into therapeutic products.

13.
Stroke ; : STROKEAHA119026049, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31587657

RESUMO

Background and Purpose- Thrombolytic treatment of acute ischemic stroke with tPA (tissue-type plasminogen activator) is hampered by its narrow therapeutic window and potential hemorrhagic complication. Vepoloxamer is a nonionic surfactant that exerts potent hemorheologic and antithrombotic properties in various thrombotic diseases. The current study investigated the effect of vepoloxamer on tPA treatment in a rat model of embolic stroke. Methods- Male Wistar rats subjected to embolic middle cerebral artery occlusion were treated with the combination of vepoloxamer and tPA, vepoloxamer alone, tPA alone, or saline initiated 4 hours after middle cerebral artery occlusion. Results- Monotherapy with tPA did not reduce infarct volume, and adversely potentiated microvascular thrombosis and vascular leakage compared with the saline treatment. Vepoloxamer monotherapy reduced infarct volume by 25% and improved brain perfusion. However, the combination treatment with vepoloxamer and tPA significantly reduced infarct volume by 32% and improved neurological function, without increasing the incidence of gross hemorrhage. Compared with vepoloxamer alone, the combination treatment with vepoloxamer and tPA robustly reduced secondary thrombosis and tPA-augmented microvascular leakage and further improved brain perfusion, which was associated with substantial reductions of serum active PAI-1 (plasminogen activator inhibitor-1) level and tPA-upregulated PAI-1 in the ischemic brain. Mechanistically, exosomes derived from platelets of ischemic rats treated with tPA-augmented cerebral endothelial barrier permeability and elevated protein levels of PAI-1 and TF (tissue factor) in the endothelial cells, whereas exosomes derived from platelets of rats subjected to the combination treatment with vepoloxamer and tPA diminished endothelial permeability augmented by tPA and fibrin and reduced PAI-1 and TF levels in the endothelial cells. Conclusions- The combination treatment with vepoloxamer and tPA exerts potent thrombolytic effects in rats subjected to acute ischemic stroke. Vepoloxamer reduces tPA-aggravated prothrombotic effect of platelet-derived exosomes on cerebral endothelial cells, which may contribute to the therapeutic effect of the combination treatment.

14.
J Endocrinol ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648186

RESUMO

Obesity is a worldwide health problem. Semaphorins are involved in axonal guidance; however, the role of secretory semaphorin 3G (SEMA3G) in regulating adipocyte differentiation remains unclear. Microarray analysis showed that the SEMA3G gene was upregulated in an in vitro model of adipogenesis. In this study, SEMA3G was highly expressed in the white adipose tissue and liver. Analysis of 3T3-L1 cell and primary mouse preadipocyte differentiation showed that SEMA3G mRNA and protein levels were increased during the middle stage of cell development. In vitro experiments also showed that adipocyte differentiation was promoted by SEMA3G; however, SEMA3G inhibition using a recombinant lentiviral vector expressing a specific small hairpin RNA (shRNA) showed the opposite results. Mice were fed a chow or high-fat diet (HFD); knockdown of SEMA3G was found to inhibit weight gain, reduce fat mass in the tissues, prevent lipogenesis in the liver tissue, reduce insulin resistance and ameliorate glucose tolerance in HFD mice. Additionally, the effect of SEMA3G on HFD-induced obesity was activated through PI3K/Akt/GSK3ß signaling in the adipose tissue and the AMPK/SREBP-1c pathway in the liver. Moreover, the plasma concentrations of SEMA3G and leptin were measured in 20 obese and 20 non-obese human subjects. Both proteins were increased in obese subjects, who also exhibited a lower level of adiponectin and presented with insulin resistance. In summary, we demonstrated that SEMA3G is an adipokine essential for adipogenesis, lipogenesis, and insulin resistance and is associated with obesity. SEMA3G inhibition may, therefore, be useful for treating diet-induced obesity and its complications.

15.
J Cell Mol Med ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657880

RESUMO

Solid tumour frequently undergoes metabolic stress during tumour development because of inadequate blood supply and the high nutrient expenditure. p53 is activated by glucose limitation and maintains cell survival via triggering metabolic checkpoint. However, the exact downstream contributors are not completely identified. BAG3 is a cochaperone with multiple cellular functions and is implicated in metabolic reprogramming of pancreatic cancer cells. The current study demonstrated that glucose limitation transcriptionally suppressed BAG3 expression in a p53-dependent manner. Importantly, hinderance of its down-regulation compromised cellular adaptation to metabolic stress triggered by glucose insufficiency, supporting that BAG3 might be one of p53 downstream contributors for cellular adaptation to metabolic stress. Our data showed that ectopic BAG3 expression suppressed p53 accumulation via direct interaction under metabolic stress. Thereby, the current study highlights the significance of p53-mediated BAG3 suppression in cellular adaptation to metabolic stress via facilitating p53 accumulation.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31640233

RESUMO

Recently, the growing release of CeO2 nanoparticles (CeO2 NPs) into sewage systems has attracted great concern. Several studies have extensively explored CeO2 NPs' potential adverse impacts on wastewater treatment plants; however, the impaired activated sludge recovery potentials have seldom been addressed to date. To explore the physicochemical and biological effects on the activated sludge performance and activity recovery of damaged sludge by exposure to CeO2 NPs in sequencing batch reactors (SBRs), four reactors and multiple indicators including water quality, key enzymes, microbial metabolites, the microbial community structure and toxicity were used. Results showed that 10-week exposure to higher CeO2 NP concentration (1, 10 mg/L) resulted in a sharp decrease in nitrogen and phosphorus removal efficiencies, which were consistent with the tendencies of key enzymes. Meanwhile, CeO2 NPs at concentrations of 0.1, 1, and 10 mg/L decreased the secretion of tightly bound extracellular polymeric substances to 0.13%, 3.14%, and 28.60%, respectively, compared to the control. In addition, two-week recovery period assays revealed that the functional bacteria Proteobacteria, Nitrospirae and Planctomycetes recovered slightly at the phyla level, as analyzed through high-throughput sequencing, which was consistent with the small amount of improvement of the effluent performance of the system. This reflected the small possibility of the activity recovery of damaged sludge.

17.
J Agric Food Chem ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31623431

RESUMO

Succinic acid (SA) is applied in the food, chemical, and pharmaceutical industries. 5-Hydroxyleucine (5-HLeu) is a promising precursor for the biosynthesis of antituberculosis drugs. Here, we designed a promising synthetic route for the simultaneous production of SA and 5-HLeu by combining l-leucine dioxygenase (NpLDO), l-glutamate oxidase (LGOX), and catalase (CAT). Two bioconversion systems: "a multienzyme cascade catalysis in vitro" (MECCS) and "whole-cell catalysis system" (WCCS) were constructed. A high-activity NpLDO mutant was screened by error-prone polymerase chain reaction (PCR) and showed 6.1-fold improvement of catalytic activity. After optimization of reaction conditions, MECSS yielded 3.15 g/L SA and 3.92 g/L 5-HLeu, while the production of SA and 5-HLeu by the most effective WCSS reached 15.12 and 18.83 g/L, respectively. This is the first attempt to use ferrous iron/α-ketoglutarate-dependent dioxygenases for the simultaneous production of SA and hydroxy-amino-acid. This research provides a tool for industrial production of food of high-value products from low-cost raw materials.

18.
Neurosci Lett ; 714: 134536, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31589904

RESUMO

Spiral ganglion neurons (SGNs) are primary afferent auditory neurons activated by inner hair cells in mammalian cochlea. Here, for the convenience of SGN studies such as patch-clamp or single cell RNA-sequence studies, a knock-in mouse (ShhCreEGFP/+; Rosa26-Tdtomatoloxp/+) was generated for the purpose of obtaining fluorescence SGNs. Auditory brainstem response (ABR) and Tuj1 immunohistochemistry staining were performed to verify the hearing function and the morphological characteristics. The results showed that there was no significant difference between shh and wild type mice. In electrophysiological studies, we verified a series of electrophysiological characteristics including the amplitude of sodium and potassium currents and action potential characteristics of shh and wild type mice and no significant differences were found either. From the above, shh mice have the same cell function and morphology as their littermate control wild type mice and could be used as an ideal tool to study the function and characteristics of spiral ganglion neurons. Potassium channels of SGNs play an important role in resolving time accuracy. We obtained similar amplitude of IK+ in neonatal and mature mice in the aging competition experiment, however, the density of IK+ from mature mice were significantly different from those of neonatal mice, a phenomenon that may play a key role in the nervous system. Potassium channels have been shown to contribute to apoptosis induced by cisplatin administration in various cell lines. Here we used cisplatin administration to study the ototoxicity and found that the effects of a low dose of cisplatin (0.5 mM correspond to therapeutic doses) causes a decrease in currents and is reversible after a short administration time. Moreover, we propose the activated state of potassium channels has changed but the characteristic and number remain still after cisplatin administration. The excess potassium ions may accumulate in the cell body, which had affected the firing properties and induce cytotoxicity and apoptosis. We suggest that the electrophysiological properties of acutely isolated SGNs may support further research on the mechanics of auditory propagation and ion channel pharmacology.

19.
HPB (Oxford) ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31607637

RESUMO

BACKGROUND: A clear definition of "early recurrence" after hepatocellular carcinoma (HCC) resection is still lacking. This study aimed to determine the optimal cutoff between early and late HCC recurrence, and develop nomograms for pre- and postoperative prediction of early recurrence. METHODS: Patients undergoing HCC resection were identified from a multi-institutional Chinese database. Minimum P-value approach was adopted to calculate optimal cut-off to define early recurrence. Pre- and postoperative risk factors for early recurrence were identified and further used for nomogram construction. The results were externally validated by a Western cohort. RESULTS: Among 1501 patients identified, 539 (35.9%) were recurrence-free. The optimal length to distinguish between early (n = 340, 35.3%) and late recurrence (n = 622, 64.7%) was 8 months. Multivariable logistic regression analyses identified 5 preoperative and 8 postoperative factors for early recurrence, which were further incorporated into preoperative and postoperative nomograms (C-index: 0.785 and 0.834). The calibration plots for the probability of early recurrence fitted well. The nomogram performance was maintained using the validation dataset (C-index: 0.777 for preoperative prediction and 0.842 for postoperative prediction). CONCLUSIONS: An interval of 8 months was the optimal threshold for defining early HCC recurrence. The two web-based nomograms have been published to allow accurate pre- and postoperative prediction of early recurrence. These may offer useful guidance for individual treatment or follow up for patients with resectable HCC.

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