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1.
Langmuir ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32019307

RESUMO

A fluorosurfactant based on 3,3,3-trifluoropropene (TFP) telomer was synthesized as an environmentally friendly alternative to perfluorooctanoic acid (PFOA) using TFP and 2-iodoperfluoropropane ((CF3)2CF-I) as starting materials. TFP telomerization was initiated by addition of di-tert-butylperoxide in the presence of (CF3)2CF-I as a chain transfer agent. The surfactant was obtained by modification of the iodine end-group on the TFP telomer to form an allylic functionality followed by the addition of thioglycolic acid via a thiol-ene reaction. The resulting fluorosurfactant exhibited a lower critical micellar concentration (CMC = 0.87 g·L-1) than that of PFOA (CMC = 3.0 g·L-1). This surfactant was used to prepare fluoropolymer nanoparticles by solvent evaporation from a solution composed of the surfacant and poly[2-(perfluorobutyl)ethyl methacrylate]. The oil-in-water emulsion was initially formed due to the adsorption of the surfactant molecules at the oil/water interface and subsequently converted into a nanoparticle suspension after solvent evaporation. Because of the strong hydrophobic interactions between the fluorinated surfactant tail and fluoropolymer, the obtained nanoparticle suspension was quite stable against water dialysis.

2.
J Int Med Res ; 48(2): 300060520903873, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32046556
3.
Chem Commun (Camb) ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040106

RESUMO

We developed a novel enzyme-free amplified SERS immunoassay by combining silver nanoparticle (AgNP)-linked immunoreaction and SERS transduction for the detection of disease biomarkers. As a proof of concept, our method was successfully illustrated with the disease biomarker α-fetoprotein with the detection limit of 3.3 × 10-13 g mL-1 and a double-blind experiment consisting of tens of serum samples was performed to confirm its reliability.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32011113

RESUMO

Although the forward diffraction of the three-dimensional (3D) photonic crystal is easily applied to a photoswitch, backward diffraction rainbows are rarely reported. The first rotational photoswitch based on a bilayer 3D photonic crystal with backward diffractions similar to those of two-dimensional photonic crystals was fabricated by vertically combining different thicknesses of nanoparticle templates. When rotating the bilayer photonic crystal, the opening or closing of the rotational photoswitch shows periodic reproducibility values of 30 and 60°. Different periods are regulated by the thickness and scattering effect of the top layer. Moreover, invisible patterns can be encoded and erased by changing the wettability via pH. Because of the decreasing of the refractive index differentials, it will be revealed rapidly when immersed in water. The revealed pattern can be periodically turned on and off by rotating the bilayer photonic crystal. It has great application prospects in optical prism, warning board, anti-counterfeiting, steganography, watermarking, and complex information coding.

5.
Langmuir ; 2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32040331

RESUMO

A free-standing (biomacomolecule/synthetic inorganic nanotubes) hybrid film was fabricated through an alternative layer-by-layer (LBL) assembly of sacran and imogolite nanotubes. Sacran is a natural polysaccharide extracted from the cyanobacterium Aphanothece sacrum, while imogolite is a natural tubular aluminosilicate clay found in volcano ash. The hybrid film thickness increased linearly with the number of the bilayers, because of the interaction between the negatively charged surface of sacran and the positively charged surface of imogolite. UV-vis spectroscopy indicated that the LBL film exhibited good transparency. The surface morphology of the LBL film was smooth in the micrometer scale; many imogolite nanotubes were adsorbed onto the sacran layer, while no imogolite clusters were observed. Furthermore, the structure, stability, gas permeability, and mechanical properties of the LBL films were investigated.

6.
Nanoscale ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32057066

RESUMO

Hybrid capacitive deionization (HCDI) has emerged as a promising desalination technique due to its ultra-high salt removal capacity in high brine water. However, the mechanism behind HCDI is seldom discussed anywhere. Herein, we perform a comprehensive investigation to have some insight into the HCDI behavior of NaxCoO2 by varying x as 0.2, 0.5, 0.7, 1.0 and 1.6. Regardless of x, NaxCoO2 are classified as a representative P63/mmc space group with a P2 layered structure. With the increase of the sodium content, the (002) crystal plane of NaxCoO2 shifts significantly toward a high angle as the distance between CoO2 layers decreases. This results from the variation of the Na-O bonding length as well as the bonding energy according to the first-principles simulation. Moreover, it is observed that the Na-O bond broke once the input energy is higher than the Na-O bonding energy, leading to the electrochemical pre-activation of NaxCoO2. As a result, Na0.7CoO2 exhibits the best HCDI performance, i.e. a salt removal capacity of 63.0 mg g-1 and a charge efficiency of 97% in NaCl solutions with an initial conductivity of 2000 µS cm-1. Besides, the intercalation of sodium ions into NaxCoO2 has been confirmed by differentiating the respective contributions of pseudo-capacitance together with crystal phase transformation. Our results show that the desalination behavior of NaxCoO2 can be mediated by controlling the sodium content and electrochemical pre-activation.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32057078

RESUMO

OBJECTIVES: Aortic dissection (AoD) in the presence of an aberrant right subclavian artery (ARSA) is very rare. Clinical experience is limited, and there is no consensus regarding the optimal management strategy. We seek to evaluate the safety and efficacy of the total arch replacement (TAR) and frozen elephant trunk (FET) technique as an approach to AoD in patients with ARSA by retrospectively analysing our single-centre experience. METHODS: From 2009 to 2017, we performed TAR + FET for 22 patients with ARSA sustaining AoD (13 acute, 59.1%). The mean age was 46.0 years [standard deviation (SD) 8.3], and 19 patients were male (86.4%). ARSA orifice was dilated in 15 (68.2%) patients, and a Kommerall diverticulum was diagnosed in 13 (59.1%) patients with a mean diameter of 21.8 mm (SD 7.7; range 15-40). Surgery was performed via femoral and right/left carotid cannulation under hypothermic circulatory arrest at 25°C. The ARSA was reconstructed using a separate branched graft. RESULTS: ARSA was closed proximally by ligation in 16 (72.7%) patients, direct suture in 4 (18.2%) patients and both in 2 (9.1%) patients. Operative mortality was 13.6% (3/22). Type Ib endoleak occurred in 1 (4.5%) patient at 8 days. Follow-up was complete in 100% at mean 4.2 years (SD 2.0), during which 3 late deaths and 1 reintervention for type II endoleak occurred. Survival was 81.8% and 76.4% at 3 and 5 years, respectively. Freedom from reoperation was 89.2% up to 8 years. In competing risks analysis, the incidence was 22.1% for death, 10.8% for reoperation and 67.1% for event-free survival at 5 years. The false lumen, ARSA orifice and Kommerall diverticulum were obliterated in 100%. Grafts were patent in 100%. No patients experienced cerebral ischaemia and upper extremity claudication. Hypothermic circulatory arrest time (min) was sole predictor for death and aortic reintervention (hazard ratio 1.168, 95% confidence interval 1.011-1.348; P = 0.034). CONCLUSIONS: The TAR and FET technique is a safe and efficacious approach to AoD in patients with ARSA. Modifications of routine TAR + FET techniques are essential to successful repair, including femoral and right/left carotid artery cannulation, ligation of ARSA on the right side of the trachea and ARSA reconstruction with a separate graft.

8.
Small ; : e1907468, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32068961

RESUMO

Advanced functional materials enable lithium-ion batteries to reach high specific capacity. To achieve this goal, nickel foam (NF), as current collector, is chosen to in situ form aligned nanoarrays composed of CoP3 /carbon polyhedron (CP)/CoO. The CoO nanowire acts as bridge to link NF and CoP3 /CP which not only reinforces the adhesion between active material and NF but also enhances the capacity of whole electrode. Besides, CoP3 is evenly coupled with CP, which can effectively buffer the volume expansion of CoP3 during the charge/discharge process. Moreover, the novel architecture of CoP3 /CP/CoO/NF is beneficial to improve the electronic conductivity. As a result, the CoP3 /CP/CoO/NF anode delivers an ultrahigh specific capacity of 1715 mAh g-1 at 0.5 A g-1 which can remain at 1150 mAh g-1 after 80 cycles, demonstrating the good durability. Thus, this work develops a facile strategy to design self-supporting electrodes for an enhanced energy storage device.

9.
Org Lett ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32013456

RESUMO

The Cu-catalyzed 1,4-protosilylation and protoborylation of trifluoromethyl-substituted conjugated enynes were developed to access functionalized homoallenylsilanes and homoallenylboronates. This protocol also provides a general method to synthesize optically active homoallenylsilanes and homoallenylboronates in moderate to excellent yields with high enantiomeric excess by using new designed chiral bisoxazoline ligands. Simultaneously, the transformations of homoallenylsilanes and homoallenylboronates were also explored to synthesize useful building blocks.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32026680

RESUMO

Owing to superior sorption properties, structural variability and versatility, metal-organic frameworks (MOFs) make themselves well as sensing materials with both high selectivity and sensitivity. Herein, integrating MOF with polymer, a multilayered photonic crystal (PC) sensor which is composed of NH2-MIL-88B nanocrystals and poly(styrene-acrylic acid) nanoparticles is fabricated. Synthetically taking advantage of sensitive breathing effect of the MOF and excellent stimuli-response of the copolymer, the sensor outputs significant optical signal that can be visually recognized and captured with the assistance of spectrum with the detection limits of 3.70, 0.87, 0.42 and 0.22 g/m3 when exposed to benzene, toluene, ethylbenzene and xylene (BTEX), respectively. Thanks to porous construction and ultrathin feature, the PC sensor reaches sensing balance within 3 s in BTEX streams and restores its initial state immediately after rapid volatilization of the vapors. The function of the MOF material is confirmed by comparing the sensing properties of MOF/polymer PC with that of SiO2/polymer one. In addition, as the designed MOF/polymer-based PC sensor shows different spectrum characteristics compared with other reported MOF-based ones, finite element simulation technology is adopted to help explain the relationship between optical property and material structure feature of multilayered PC structure.

11.
Chem Commun (Camb) ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32051985

RESUMO

A conductive polymer thin film having choline phosphate as the side group was prepared. Quartz crystal microbalance (QCM) was employed to evaluate the adsorption of the model protein, bovine serum albumin (BSA), on the films deposited on indium tin oxide (ITO) electrodes. Cell adsorption on the film was evaluated by a fibroblast NIH3T3.

12.
Chem Commun (Camb) ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32044897

RESUMO

In this study, an efficient strategy for the synthesis of dumbbell-shaped amphiphilic copolymers with cyclic moieties as the two bells was developed and the enhanced performance of dumbbell-shaped copolymers for controlled drug release because of the simultaneous introduction of two macrocycles was disclosed.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31957620

RESUMO

BACKGROUND: Brain-derived neurotrophic factor (BDNF) plays critical roles during development of the central and peripheral nervous systems, as well as in neuronal survival after injury. Although proBDNF induces neuronal apoptosis after injury in vivo, whether it can also act as a death factor in vitro and in vivo under physiological conditions and after nerve injury, as well as its mechanism of inducing apoptosis, is still unclear. OBJECTIVE: In this study, we investigated the mechanisms by which proBDNF causes apoptosis in sensory neurons and satellite glial cells (SGCs) in dorsal root ganglia (DRG) after sciatic nerve transection (SNT). METHODS: SGCs cultures were prepared and a scratch model was established to analyze the role of proBDNF in sensory neurons and SGCs in DRG following SNT. Following treatment with proBDNF antiserum, TUNEL and immunohistochemistry staining were used to detect expression of glial fibrillary acidic protein (GFAP) and calcitonin gene-related peptide (CGRP) in DRG tissue; immunocytochemistry and Cell Counting Kit-8 (CCK8) assay were used to detect GFAP expression and cell viability of SGCs, respectively. RT-qPCR, western blot, and ELISA were used to measure mRNA and protein levels, respectively, of key factors in BDNF-TrkB, proBDNF-p75NTR/sortilin, and apoptosis signaling pathways. RESULTS: proBDNF induced mitochondrial apoptosis of SGCs and neurons by modulating BDNF-TrkB and proBDNF-p75NTR/sortilin signaling pathways. In addition, neuroprotection was achieved by inhibiting the biological activity of endogenous proBDNF protein by injection of anti-proBDNF serum. Furthermore, the anti-proBDNF serum inhibited the activation of SGCs and promoted their proliferation. CONCLUSION: proBDNF induced apoptosis in SGCs and sensory neurons in DRG following SNT. The proBDNF signaling pathway is a potential novel therapeutic target for reducing sensory neuron and SGC loss following peripheral nerve injury.

14.
J Neuroinflammation ; 17(1): 17, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926564

RESUMO

BACKGROUND: Dendritic cell-associated C-type lectin-1 (Dectin-1) receptor has been reported to be involved in neuroinflammation in Alzheimer's disease and traumatic brain injury. The present study was designed to investigate the role of Dectin-1 and its downstream target spleen tyrosine kinase (Syk) in early brain injury after ischemic stroke using a focal cortex ischemic stroke model. METHODS: Adult male C57BL/6 J mice were subjected to a cerebral focal ischemia model of ischemic stroke. The neurological score, adhesive removal test, and foot-fault test were evaluated on days 1, 3, 5, and 7 after ischemic stroke. Dectin-1, Syk, phosphorylated (p)-Syk, tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) expression was analyzed via western blotting in ischemic brain tissue after ischemic stroke and in BV2 microglial cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury in vitro. The brain infarct volume and Iba1-positive cells were evaluated using Nissl's and immunofluorescence staining, respectively. The Dectin-1 antagonist laminarin (LAM) and a selective inhibitor of Syk phosphorylation (piceatannol; PIC) were used for the intervention. RESULTS: Dectin-1, Syk, and p-Syk expression was significantly enhanced on days 3, 5, and 7 and peaked on day 3 after ischemic stroke. The Dectin-1 antagonist LAM or Syk inhibitor PIC decreased the number of Iba1-positive cells and TNF-α and iNOS expression, decreased the brain infarct volume, and improved neurological functions on day 3 after ischemic stroke. In addition, the in vitro data revealed that Dectin-1, Syk, and p-Syk expression was increased following the 3-h OGD and 0, 3, and 6 h of reperfusion in BV2 microglial cells. LAM and PIC also decreased TNF-α and iNOS expression 3 h after OGD/R induction. CONCLUSION: Dectin-1/Syk signaling plays a crucial role in inflammatory activation after ischemic stroke, and further investigation of Dectin-1/Syk signaling in stroke is warranted.

15.
Arch Biochem Biophys ; 681: 108279, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31982394

RESUMO

Because long-term occupational exposure to low concentrations of acrylamide (ACR) has the potential to cause neurological damage, it is important to identify biomarkers that can be used to evaluate this risk. In the present study, urine metabolomics of the ACR-exposed and non-exposed groups to identify potential metabolites was carried out using ultra high performance liquid chromatography coupled with quadrupole time of flight mass spectrometry. Serum biochemical indexes of the exposed and non-exposed groups were also determined. Principal component analysis showed a differential separation between exposed group and non-exposed group and a total of 7 metabolites were identified in positive and negative ionization modes; Area under curve of anthranilic acid, ß-guanidinopropionic acid and mesobilirubinogen were 0.980, 0.843 and 0.801 respectively and these metabolites showed high sensitivity and specificity. The 13 biochemical indexes were divided into three classes based on physiological functions. Only biomarkers of dysregulated liver function including alanine aminotransferase, aspartic transaminase, total bilirubin, direct bilirubin and triglyceride were significantly higher in the exposed group than in the non-exposed group. This study identifies important related metabolic changes in the bodies of workers after long-term occupational exposure to low concentration ACR and suggests new biomarkers of nervous system injury caused by ACR. The study also provides a sound basis for exploring the biochemical mechanisms and metabolic pathways of nervous system toxicity caused by ACR.

16.
Nanoscale ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31993600

RESUMO

Homo-junction and multi-layer structures of transition metal chalcogenide (TMD) materials provide great flexibility for band-structure engineering and designing photoelectric devices. However, the knowledge of van der Waals epitaxy growth limits the development of these heterostructures. Herein, we employed the chemical vapor deposition (CVD) growth strategy to synthesize novel WSe2 homo-junction samples with a triangular monolayer in the center and three AA stacking bilayer flakes connected to the vertexes of the monolayer. The emitted photon energy from the bilayer near the junction showed a blueshift in energy of up to 24 meV compared with bare bilayer WSe2, confirming the charge transfer effect from monolayer to bilayer WSe2. Further growth studies revealed the shape evolution from WSe2 homo-junction to bilayer. The whole homo-junction formation and evolution process cannot be explained by the traditional layer-by-layer growth mechanism. Instead, a direct bilayer growth approach is proposed to explain the bilayer formation and evolution at the vertexes of the bottom layer of WSe2. These findings suggest that the growth of bilayer TMDs is more complex than our previous understanding. This work presents deepens insight into van der Waals epitaxy growth, and thus is valuable for guiding the fabrication of novel homo-junctions for both fundamental science and optoelectronic applications.

17.
Gene ; 731: 144324, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31904498

RESUMO

BACKGROUND/AIMS: lncRNA NEAT1 is involved in the development of many diseases. However, the function of lncRNA NEAT1 in myocardial infarction is unclear. Therefore, this experimental design based on lncRNA NEAT1 to explore the pathogenesis of myocardial infarction. METHODS: RT-qPCR was used to detect the expression of lncRNA NEAT1 and miR-378a-3p in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. MTT assay, flow cytometry, Caspase-3 kit and transwell assay were used to detect the effects of lncRNA NEAT1 and miR-378a-3p on cardiomyocyte proliferation, apoptosis and migration. Target gene prediction and screening, luciferase reporter assays were used to verify downstream target genes for lncRNA NEAT1 and miR-378a-3p. Western blotting was used to detect the protein expression of Atg12 and related autophagy genes. RESULTS: lncRNA NEAT1 was highly expressed in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. Moreover, lncRNA NEAT1 significantly promoted cell proliferation and migration of cardiomyocytes. In addition, lncRNA NEAT1 inhibited miR-378a-3p expression, and miR-378a-3p inhibited Atg12 expression, while lncRNA NEAT1 regulated expression of Atg12 and related autophagic factors via miR-378a-3p. Knockout of microRNA-378-3p reversed the effects of NEAT1 silencing on cell damage. CONCLUSION: lncRNA NEAT1 can regulate the proliferation of cardiomyocytes by regulating miR-378-3p/Atg12 axis, thus accelerating the occurrence and development of cardiomyocytes.

18.
Org Lett ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31999462

RESUMO

A novel method of metal-free dehydrogenative silylation of enamides has been developed. The desired functionalized vinylsilane products were obtained in moderate to good yield and with high stereoselectivities. This protocol displays good tolerance of various functionalities. Furthermore, the high chemoselectivity of this reaction enables us to introduce different unsaturated C-C moieties to the products. The ease of further derivatization of the products to other useful compounds also demonstrates the highly synthetic utility of the current methodology.

19.
Langmuir ; 36(5): 1379-1385, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31967842

RESUMO

Utilizing photonic crystals to fabricate information encryption materials has attracted widespread interest due to their tunable optical properties and responsiveness to external stimuli. In most of the previously reported systems, the information is hidden at a specific angle and the angle-dependent invisibility is a limitation. Meanwhile, poor structural stability is still a key issue that needs to be solved for potential applications. In this paper, a bilayer heterostructure photonic crystal containing ordered hollow silica inverse opal arrays, amorphous silica opal arrays, and poly(vinyl alcohol) (adhesive) is successfully constructed. It makes the information highly invisible at any angle and also achieves information encryption. With this strategy, the information can be hidden by the noniridescent structural color derived from the strong scattering effect of light from the top layer of amorphous silica sphere arrays. After wiping with ethanol or a refractive-index-matching solvent, the scattering effect vanishes and the amorphous silica sphere arrays become transparent. The reflected light of the bottom layer caused by the increasing refractive index contrast between the inside and outside of the hollow silica spheres could rapidly reveal the hidden information. The bilayer photonic crystal exhibits robust structural stability, and the hiding/revealing process is completely reversible, which shows great potential applications in steganography and information encryption.

20.
Retina ; 40(1): 33-40, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30300265

RESUMO

PURPOSE: To compare the efficiency of releasable scleral buckling (RSB) and pars plana vitrectomy (PPV) in the treatment of phakic patients with primary rhegmatogenous retinal detachment. METHODS: The current study was a prospective randomized clinical trial. One hundred and ten eyes from 110 patients with primary rhegmatogenous retinal detachment and proliferative vitreoretinopathy of Grade B or less were included in this study. The patients were randomly allocated into an RSB group and a PPV group. The functional and anatomical success was compared between groups. RESULTS: The primary anatomical success rate (PPV 41/43 [95.35%] and RSB 38/41 [92.68%]) and final anatomical success rate (PPV and RSB 100%) showed a nonsignificant difference. The best-corrected visual acuity, intraocular pressure, and complications were not different between the groups. However, the incidence of cataract progression was higher in the PPV group (26 of 43 [60.47%]) than in the RSB group (4 of 41 [9.76%]) at the 12-month follow-up. The subfoveal choroidal thickness increased significantly in the RSB group 3 months after surgery, but no longer differed at the postoperative 6-month and 12-month follow-ups. The axial length had increased significantly 1 month after surgery, but the difference was no longer significant at 3 months, 6 months, and 12 months. CONCLUSION: The RSB and PPV procedures have the same effects on the functional and anatomical success for patients with phakic primary rhegmatogenous retinal detachment. Nevertheless, based on the few cases of intraocular complications and cataract progression, we believe that the RSB technique should be preferentially recommended.

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