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2.
Neural Regen Res ; 16(8): 1574-1581, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33433486

RESUMO

Studies have shown that hyperglycemia aggravates brain damage by affecting vascular endothelial function. However, the precise mechanism remains unclear. Male Sprague-Dawley rat models of diabetes were established by a high-fat diet combined with an intraperitoneal injection of streptozotocin. Rat models of traumatic brain injury were established using the fluid percussion method. Compared with traumatic brain injury rats without diabetic, diabetic rats with traumatic brain injury exhibited more severe brain injury, manifested as increased brain water content and blood-brain barrier permeability, the upregulation of heme oxygenase-1, myeloperoxidase, and Bax, the downregulation of occludin, zona-occludens 1, and Bcl-2 in the penumbra, and reduced modified neurological severity scores. The intraperitoneal injection of a nitric oxide synthase inhibitor N(5)-(1-iminoethyl)-L-ornithine (10 mg/kg) 15 minutes before brain injury aggravated the injury. These findings suggested that nitric oxide synthase plays an important role in the maintenance of cerebral microcirculation, including anti-inflammatory, anti-oxidative stress, and anti-apoptotic activities in diabetic rats with traumatic brain injury. The experimental protocols were approved by the Institutional Animal Care Committee of Harbin Medical University, China (approval No. ky2017-126) on March 6, 2017.

3.
J Sci Food Agric ; 101(1): 287-296, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32627844

RESUMO

BACKGROUND: Polyphenols extracted from plants are usually highly unstable and rapidly transformed into various reaction products during food and drug processing, thus limiting their applications. To improve the stability and solubility of polyphenols from the leaves of Chinese star anise (Illicium verum Hook. f.), and hence to expand their application to food and medicine, the extracted anise leaf polyphenols (ALPs) were microencapsulated using ß-cyclodextrin (ß-CD) and cyclodextrin-based metal-organic frameworks (ß-CD-MOFs). RESULTS: The optimum inclusion rate of ALP/ß-CD-MOFs was 97.80% at a core-wall ratio of 1:10. Meanwhile, the stabilities, solubilities and antioxidant activities of the polyphenols before and after inclusion were compared. The results showed both the stabilities and solubilities of ALP/ß-CD-MOFs were significantly improved compared with those of ALPs and ALP/ß-CD, suggesting the potential of ß-CD-MOFs as newer and better carriers than ß-CD for polyphenols in food industry applications. The free radical (including superoxide, hydroxyl and DPPH radicals) scavenging activities were also improved by microencapsulation. Superoxide radical scavenging reaction also showed slow-release property of ALP/ß-CD-MOFs. The formation of the inclusion complex was further confirmed using Fourier transform infrared spectral characterization. CONCLUSIONS: Microencapsulation with ß-CD-MOFs could expand the application scope of ALPs, and it is more effective than encapsulation with ß-CD. This is important for a better understanding and application of this useful traditional Chinese plant. As a new material with high efficiency and edibility, ß-CD-MOFs are not limited to the chemical field, but also have potential in new areas of food, medicine and healthcare products. © 2020 Society of Chemical Industry.

5.
Environ Pollut ; : 115943, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33158624

RESUMO

Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.

6.
Oxid Med Cell Longev ; 2020: 1208726, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33144913

RESUMO

Idesia polycarpa Maxim. var. vestita Diels (I. polycarpa) is well known as an edible oil plant which contains abundant linoleic acid and polyphenols. The objective of this study was to maximize the by-product of defatted fruit of I. polycarpa. We found that the fraction D of ethyl acetate extract (EF-D) contained more polyphenols, which contribute to its strong antioxidant activity by antioxidant assays (DPPH, ABTS, and FRAP). Meanwhile, EF-D showed a significant lipid-lowering effect on oleic acid- (OA-) induced hepatic steatosis in HepG2 cells through enhancing antioxidant activity, reducing liver damage, and regulating lipid metabolism, antioxidant, and inflammation-related gene expression. The SOD and T-AOC levels significantly increased, but the levels of MDA, AST, and ALT decreased obviously when treated with EF-D. In general, EF-D improved the antioxidant enzyme activities and decreased the hepatic injury activities. Besides, treatment with EF-D for NAFLD influenced lipid metabolism and inflammation by activating PPARα which was associated with the increased expression of CPT1 and decreased expression of SCD, NF-κB, and IL-1. Moreover, EF-D improved the oxidative stress system through activation of the Nrf2 antioxidant signal pathways and upregulated its target genes of HO-1, NQO1, and GSTA2. The results highlighted the EF-D from the defatted fruit of I. polycarpa regarding lipid-lowering, proving it to be a potential drug resource of natural products for treating the nonalcoholic fatty liver disease (NAFLD).

7.
Sci Total Environ ; : 143640, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33248765

RESUMO

This study reports a novel adsorbent structure and shows the satisfactory removal performance of Pb(II) and Ni(II). The fabric structure increases the strength of the hydrogel. The hydrogel plays a major role in the composite structure as a matrix, while the fabric bears the applied load and protects the structure from mechanical damage. The double-network composite hydrogel is reinforced by plasma grafted polylactic acid melt-blown non-woven fabric and polyethylene glycol dimaleate, and its compressive strength reaches 40.6 kPa at 60% strain. The interface substantially improves the compression strength by 42.9%. Through the adsorption isotherm model, the adsorption capacity of the hydrogel for Pb(II) and Ni(II) reaches 233.12 and 165.06 mg/g, respectively, and the removal rate of heavy metal ions in water at low concentrations exceeds 95%, showing the excellent removal rate of heavy metals. Even after the fifth cycle, the removal efficiency barely declines, indicating the feasibility of repeatedly use. Cost analysis reveals that the adsorbent is relatively low cost, solving the problems of difficult recovery, low strength, and easy damage of hydrogel adsorbents, and promoting the industrial application of hydrogels as adsorbents.

8.
ACS Appl Mater Interfaces ; 12(49): 55072-55082, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33252221

RESUMO

To simply and effectively enhance the conversion capability of wearable thermoelectric textiles, a two-step in situ method is adopted to fabricate dual-shell photothermoelectric textiles which is made of polypropylene fibers with a photo-thermal layer (PPy) and a thermoelectric layer (PEDOT:Tos). The PPy is tailored to achieve high temperature and photothermoelectric effects. The PPy layer can significantly increase the photothermal conversion efficiencies of as-prepared fabric. The optimized photothermoelectric fabric can improve the generated voltage output from 294.13 to 536.47 µV under the infrared light, and its power density is up to 13.76 nW·m-2. A flexible photothermoelectric strip composed of as-prepared fabric coated with Ag particles and textile substrates with low thermal conductivity shows a voltage output of 2.25, 0.677, and 0.183 mV and a power output of 0.7031, 0.0636, and 0.0049 nW under IR light, sunlight, and on the arm, respectively. The photothermoelectric fabrics display potential as to a new smart wearable device for converting light and electricity.

9.
J Pain Res ; 13: 2673-2684, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116809

RESUMO

Purpose: To investigate the impact of body mass index (BMI) on the analgesic effects and adverse reactions of patient-controlled intravenous analgesia (PCIA). Methods: From 2017 to 2018, 390 patients undergoing open gastrointestinal surgery were reviewed at West China Hospital, Sichuan University. All used PCIA of sufentanil combined with dexmedetomidine and flurbiprofen axetil. According to their BMIs, they were placed into six groups: group A (BMI < 18.5kg/m2, 29), group B (18.5kg/m2 ≤ BMI< 22kg/m2, 124), group C (22kg/m2 ≤ BMI < 24kg/m2, 99), group D (24kg/m2 ≤ BMI < 26kg/m2, 69), group E (26kg/m2 ≤ BMI < 28kg/m2, 46) and group F (BMI ≥28kg/m2, 23). Main data of the perioperative use of analgesics, postoperative visual analogue score (VAS), and adverse reactions were collected. Results: Twenty-four hours (h) after surgery, patients in group A had a higher resting VAS than the other groups, especially B (pA-B = 0.011). VAS of patients during activity in group B was lower than those in group C 48 h after surgery (p = 0.013). Compared with groups B to F, group A had a significantly lower incidence of hypertension (p = 0.012) and a significantly higher incidence of vomiting 24 h after surgery (p = 0.009). Binary logistic analysis found that higher age was a risk factor for vomiting 24 h after surgery (OR 1.158, p = 0.045). Conclusion: Using the same PCIA, patients with BMIs of less than 18.5 kg/m2 had worse analgesia on the first day after surgery and were more likely to vomit. Postoperative analgesia and related experiences in patients with BMIs of less than 18.5 kg/m2 need to be improved.

10.
Planta ; 252(5): 78, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33033954

RESUMO

MAIN CONCLUSION: Cadmium stress induces WDR5a expression to promote NO accumulation to repress root meristem growth via suppressing auxin transport and synthesis in Arabidopsis. Nitric oxide (NO) synthase (NOS)-like activity plays a vital role in toxic cadmium (Cd)-induced NO production and inhibition of root meristem growth, while factor(s) regulating NOS-like activity and root meristem growth in plant response to Cd has not been identified yet. Here, we report that WD40 repeat 5a (WDR5a) functions in Cd-induced NOS-like activity, NO accumulation and root meristem growth suppression. We found that wdr5a-1 mutant root has increased root meristem growth with lower NOS-like activity and NO accumulation than wild type upon Cd exposure, and exogenous NO donors sodium nitroprusside or nitrosoglutathione can restore its reduced Cd sensitivity. In addition, Cd activates WDR5a expression in roots, and overexpressing WDR5a results in increased NO accumulation and suppressed root meristem growth similar to Cd-stressed wild-type roots, while scavenging NO or inhibiting NOS-like activity significantly reverts these effects of Cd. Furthermore, WDR5a acts in Cd-repressed auxin accumulation through reducing the levels of auxin efflux carriers PIN1/3/7 and biosynthetic enzyme TAA1, and reduced sensitivity of wdr5a-1 root meristem to Cd can be partially reverted by inhibiting TAA1 activity pharmaceutically or mutating TAA1 genetically. This study identified WDR5a as a key factor modulating NO accumulation and root meristem growth in plant response to Cd.

11.
Chem Commun (Camb) ; 56(87): 13393-13396, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33034592

RESUMO

Herein a facile and versatile hydrothermal method has been developed to construct a polypyrrole-derived carbon nanotube (PCN), MoS2 nanosheets and a carbon shell integrated sandwich-like heterostructure (PCN@MoS2@C). This heterostructure shows excellent performance in the hydrogen evolution reaction (HER) over a wide pH range. The results indicate that the porous carbon shell coated heterostructure provides MoS2 nanosheets with sufficient conductivity, increased number of active sites, and strong structural stability, and thus boosts its HER performance.

12.
Nanomaterials (Basel) ; 10(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066527

RESUMO

Particulate matter 2.5 (PM2.5) has become a public hazard to people's lives and health. Traditional melt-blown membranes cannot filter dangerous particles due to their limited diameter, and ultra-fine electrospinning fibers are vulnerable to external forces. Therefore, creating highly efficient air filters by using an innovative technique and structure has become necessary. In this study, a combination of polypropylene (PP) melt-blown and polyvinyl alcohol (PVA)/zeolite imidazole frameworks-8 (ZIF-8) electrospinning technique is employed to construct a PP/PVA/ZIF-8 membrane with a hierarchical fibrous structure. The synergistic effect of hierarchical fibrous structure and ZIF-8 effectively captures PM2.5. The PP/PVA composite membrane loaded with 2.5% loading ZIF-8 has an average filtration efficacy reaching as high as 96.5% for PM2.5 and quality factor (Qf) of 0.099 Pa-1. The resultant membrane resists 33.34 N tensile strength and has a low pressure drop, excellent filtration efficiency, and mechanical strength. This work presents a facile preparation method that is suitable for mass production and the application of membranes to be used as air filters for highly efficient filtration of PM2.5.

13.
Small ; 16(43): e2004614, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33015948

RESUMO

In the preparation of nanomaterials, the kinetics and thermodynamics in the reaction can significantly affect the structures and phases of nanocrystals. Therefore, people are keen to adopt various synthetic strategies to accurately assemble the target nanocrystals, and reveal the underlying mechanism of the formation of specific structures. In this work, the total reaction time is adjusted to let the prepared MnCo Prussian blue analogous (MnCoPBA) crystals show four evolving morphological changes at different stages with the assistance of sodium dodecyl sulfate. Furthermore, it is clearly observed that the epitaxial growth along the (100) plane on the shell of MnCoPBA nanocrystals is favored, and the thermodynamics and kinetics in the morphology change process are analyzed in detail. Through the simple pyrolysis, MnCoPBA crystals can be successfully converted into the corresponding carbon composites, of which Mn2 Co2 C nanoparticles are evenly distributed in highly graphitized carbon matrix. Among them, PBA-III-700 performs good oxygen reduction reaction performance in alkaline solution with the half-wave potential of 0.801 V and diffusion-limited current density of 5.36 mA cm-2 , and its zinc-air battery exhibits the peak power density of 103.4 mW cm-2 competitive with commercial Pt/C.

14.
Biomed Pharmacother ; 132: 110872, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33068936

RESUMO

Liver kinase B1 (LKB1) is an essential serine/threonine kinase frequently associated with Peutz-Jeghers syndrome (PJS). In this review, we provide an overview of the role of LKB1 in conferring protection to cancer cells against metabolic stress and promoting cancer cell survival and invasion. This carcinogenic effect contradicts the previous conclusion that LKB1 is a tumor suppressor gene. Here we try to explain the contradictory effect of LKB1 on cancer from a metabolic perspective. Upon deletion of LKB1, cancer cells experience increased energy as well as oxidative stress, thereby causing genomic instability. Meanwhile, mutated LKB1 cooperates with other metabolic regulatory genes to promote metabolic reprogramming that subsequently facilitates adaptation to strong metabolic stress, resulting in development of a more aggressive malignant phenotype. We aim to specifically discuss the contradictory role of LKB1 in cancer by reviewing the mechanism of LKB1 with an emphasis on metabolic stress and metabolic reprogramming.

15.
Plant Sci ; 299: 110604, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32900442

RESUMO

Plants relocate nutrients and energy from aging leaves to developing tissues during leaf senescence, which is important for plant growth, development, and responses to various environmental stimuli. Both jasmonic acid (JA) and H2O2 are two crucial signalling molecules positively regulating leaf senescence, whereas whether and how they are coordinated in leaf senescence remains elusive. Here, we report that H2O2 accumulates in JA-treated leaves, while scavenging the increased H2O2 can significantly suppresses JA-induced leaf senescence and the expression of senescence-associated genes (SAGs). The mutant myc2 with a mutation of MYC2, a master transcription factor in JA signalling pathway, exhibits delayed leaf senescence with increased catalase activity and decreased H2O2 accumulation compared with the wild type upon JA treatment. Further study showed that MYC2 downregulates CATALASE 2 (CAT2) expression by binding to its promoter, thus promoting JA-induced H2O2 accumulation and leaf senescence. Moreover, the delayed leaf senescence with reduced H2O2 accumulation and SAGs expression of the myc2 mutant is significantly reverted by the cat2-1 mutation in myc2 cat2-1 double mutant. Thus, our study reveals that JA represses CAT2 expression to increase H2O2 accumulation, thus promoting leaf senescence in a MYC2 dependent manner in Arabidopsis.

16.
Artigo em Inglês | MEDLINE | ID: mdl-32982961

RESUMO

In our previous study, we have shown that CRLF1 can promote proliferation and metastasis of papillary thyroid carcinoma (PTC); however, the mechanism is unclear. Herein, we investigated whether the interaction of CRLF1 and MYH9 regulates proliferation and metastasis of PTC cells via the ERK/ETV4 axis. Immunohistochemistry (IHC), qPCR, and Western blotting assays were performed on PTC cells and normal thyroid cells to profile specific target genes. In vitro assays and in vivo assays were also conducted to examine the molecular mechanism. Results showed that CRLF1 directly bound MYH9 to enhance the stability of CRLF1 protein. Inhibition of MYH9 in PTC cells overexpressing CRLF1 significantly reversed malignant phenotypes, and CRLF1 overexpression activated ERK pathway, in vitro, and in vivo. RNA-sequencing revealed that ETV4 is a downstream target gene of CRLF1, which was up-regulated following ERK activation. Moreover, it was revealed that ETV4 is highly expressed in PTC tissues and is associated with poor prognosis. Finally, the ChIP assays showed that ETV4 induces the expression of matrix metalloproteinase 1 (MMP1) by binding to its promoter on PTC cells. Altogether, our study demonstrates that CRLF1 interacts with MYH9, promoting cell proliferation and metastasis via the ERK/ETV4 axis in PTC.

17.
Chemosphere ; 254: 126873, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957285

RESUMO

The removal of organic pollutants from water is highly desired because of the development of industrial and social economy. Superhydrophilic and underwater superoleophobic membranes are emerging materials for effective oil/water separation. In this paper, superhydrophilic and underwater superoleophobic polypropylene (PP) melt-blown membranes were prepared through melt-blown and in situ growth method, achieving highly efficient oil/water separation. After in situ growth, polydopamine (PDA) grows on the surface of PP fibers, and the addition of coupling agent (3-aminopropyltriethoxysilane, APTES) can improve the stability of the membrane in harsh environments (1 M HCl, 1 M NaOH, 1 M NaCl). The PDA/APTES@PP membrane could dramatically enhance the wetting (water contact angle ∼0, underwater oil contact angle∼154°) compare with the pristine PP melt-blown membrane (water contact angle ∼130°, underwater oil contact angle ∼0). Moreover, the filtration performance is at a high level (∼99%). The behaviors are comparable or even superior to the typical reported results in the references (such as the mussel-inspired superhydrophilic PVDF membrane and copper mesh). This method provides a facile route to prepared multi-functional membrane for highly efficiency oil/water separation and industrial oily wastewater remediation.


Assuntos
Indóis/análise , Polímeros/análise , Cobre , Interações Hidrofóbicas e Hidrofílicas , Membranas Artificiais , Óleos , Águas Residuárias , Água , Purificação da Água , Molhabilidade
18.
Inorg Chem ; 59(19): 14184-14192, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32935977

RESUMO

The electrochemical reduction of CO2 using intermittent renewable electricity is an attractive strategy for producing value-added fuels and chemicals, but until now, it has been greatly hindered by the shortage of high-performance electrocatalysts. In this study, we have demonstrated a type of molecular-catalyst-based hybrid material by the polymerization of cobalt phthalocyanine (CoPc) on a three-dimensional (3D) g-C3N4 nanosheet-carbon nanotube support for the aqueous electrochemical reduction of CO2. The electrocatalytic results show that the obtained composite can selectively transform CO2 to CO with considerable Faradaic efficiency (FE) of 95 ± 1.8%, a turnover frequency of 4.9 ± 0.2 s-1, and excellent long-term stability over 24 h at -0.8 V vs the reversible hydrogen electrode (RHE). In comparison to the analogous hybrid electrocatalysts prepared by the drop-drying or dip-coating method, the polymeric form of the molecular catalyst immobilized on 3D carbonaceous materials with an interconnected network enlarges the electrochemically active surface area and enhances the structural and operational robustness.

19.
Chem Commun (Camb) ; 56(62): 8750-8753, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32749394

RESUMO

Chemical vapor deposition (CVD) and normal pulse voltage (NPV) are adopted to construct high-quality graphene-wrapped CuO nanoflowers grown in situ on copper foam (CuO NP@G/CF) as an efficient oxygen evolution reaction (OER) electrocatalyst. The CuO NF@G/CF electrode exhibits a small overpotential of 320 mV to drive a current density of 10 mA cm-2 with a low Tafel slope of 63.1 mV dec-1. This enhancement in OER performance stems from the synergistic effect between highly conductive graphene and hierarchically porous CuO nanoflowers with a number of high-density active sites and open spaces.

20.
J Neuroinflammation ; 17(1): 244, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32819407

RESUMO

BACKGROUND: Microglial polarization is a dynamic response to acute brain hypoxia induced by stroke and traumatic brain injury (TBI). However, studies on the polarization of microglia in chronic cerebral circulation insufficiency (CCCI) are limited. Our objective was to investigate the effect of CCCI on microglial polarization after chronic brain hypoperfusion (CBH) and explore the underlying molecular mechanisms. METHODS: CBH model was established by bilateral common carotid artery occlusion (2-vessel occlusion, 2VO) in rats. Using the stereotaxic injection technique, lenti-pre-miR-195 and anti-miR-195 oligonucleotide fragments (lenti-pre-AMO-miR-195) were injeted into the CA1 region of the hippocampus to construct animal models with high or low expression of miR-195. Immunofluorescence staining and flow cytometry were conducted to examine the status of microglial polarization. In vitro, Transwell co-culture system was taken to investigate the role of miR-195 on neuronal-microglial communication through CX3CL1-CX3CR1 signaling. Quantitative real-time PCR was used to detect the level of miR-195 and inflammatory factors. The protein levels of CX3CL1 and CX3CR1 were evaluated by both western blot and immunofluorescence staining. RESULTS: CBH induced by 2VO initiated microglial/macrophage activation in the rat hippocampus from 1 week to 8 weeks, as evaluated by increased ratio of (CD68+ and CD206+)/Iba-1 immunofluorescence. And the microglial/macrophage polarization was shifted towards the M1 phenotype at 8 weeks following CBH. The expression of CX3CL1 and CX3CR1 was increased in the hippocampus of 2VO rats at 8 weeks. An in vitro study in a Transwell co-culture system demonstrated that transfection of either primary-cultured neonatal rat neurons (NRNs) or microglial BV2 cells with AMO-195-induced M1 polarization of BV2 cells and increased CX3CL1 and CX3CR1 expression and that these effects were reversed by miR-195 mimics. Furthermore, the upregulation of miR-195 induced by lenti-pre-miR-195 injection prevented microglial/macrophage polarization to M1 phenotype triggered by hippocampal injection of lenti-pre-AMO-miR-195 and 2VO surgery. CONCLUSIONS: Our findings conclude that downregulation of miR-195 in the hippocampus is involved in CBH-induced microglial/macrophage polarization towards M1 phenotype by governing communication between neurons and microglia through the regulation of CX3CL1 and CX3CR1 signaling. This indicates that miR-195 may provide a new strategy for clinical prevention and treatment of CBH.

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