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1.
Nat Commun ; 10(1): 3912, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477721

RESUMO

Fabricating ultrathin organic semiconductor nanostructures attracts wide attention towards integrated electronic and optoelectronic applications. However, the fabrication of ultrathin organic nanostructures with precise alignment, tunable morphology and high crystallinity for device integration remains challenging. Herein, an assembly technique for fabricating ultrathin organic single-crystal arrays with different sizes and shapes is achieved by confining the crystallization process in a sub-hundred nanometer space. The confined crystallization is realized by controlling the deformation of the elastic topographical templates with tunable applied pressures, which produces organic nanostructures with ordered crystallographic orientation and controllable thickness from less than 10 nm to ca. 1 µm. The generality is verified for patterning various typical solution-processable materials with long-range order and pure orientation, including organic small molecules, polymers, metal-halide perovskites and nanoparticles. It is anticipated that this technique with controlling the crystallization kinetics by the governable confined space could facilitate the electronic integration of organic semiconductors.

2.
Neurochem Res ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31486012

RESUMO

Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) has recently been shown to promote oxidative stress and inflammation in the peripheral tissues, contributing to the pathogenesis of many diseases. Here we examined whether pre-existing higher circulating TMAO would influence cognitive function in aged rats after anesthetic sevoflurane exposure. Aged rats received vehicle or TMAO treatment for 3 weeks. After 2 weeks of treatment, these animals were exposed to either control or 2.6% sevoflurane for 4 h. One week after exposure, freezing as measured by fear conditioning test, microglia activity, proinflammatory cytokine expression and NADPH oxidase-dependent reactive oxygen species (ROS) production in the hippocampus (a key brain structure involved in learning and memory) were comparable between vehicle-treated rats exposed to control and vehicle-treated rats exposed to sevoflurane. TMAO treatment, which increased plasma TMAO before and 1 week after control or sevoflurane exposure, significantly reduced freezing to contextual fear conditioning, which was associated with increases in microglia activity, proinflammatory cytokine expression and NADPH oxidase-dependent ROS production in the hippocampus in rats exposed to sevoflurane but not in rats exposed to control. Moreover, hippocampal expression of antioxidant enzyme methionine sulfoxide reductase A (MsrA) was reduced by TMAO treatment in both groups, and TMAO-induced reduction in MsrA expression was negatively correlated with increased proinflammatory cytokine expression in rats exposed to SEV. These findings suggest that pre-existing higher circulating TMAO downregulates antioxidant enzyme MsrA in the hippocampus, which may sensitize the hippocampus to oxidative stress, resulting in microglia-mediated neuroinflammation and cognitive impairment in aged rats after sevoflurane exposure.

3.
Appl Opt ; 58(26): 7251-7257, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31504001

RESUMO

In this paper, a structural damage identification algorithm based on a single fiber Bragg grating (FBG) sensor is proposed. The signal detected by the FBG can be analyzed by the wavelet packet decomposition and back propagation neural network to obtain the damage location information. A high-speed FBG demodulation system based on a tunable Fabry-Perot filter and unbalanced Mach-Zehnder (M-Z) interferometer is designed to respond to a signal with a frequency range from 0 to 4 kHz, which will increase the sensing accuracy. This algorithm is verified by the aluminum plate model, which can simulate the generation of damage in reality. The experimental results show that a single FBG sensor is enough to realize accurate damage location identification according to this algorithm, and identification accuracy can reach 90.0%.

4.
Math Biosci Eng ; 16(5): 4182-4195, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31499657

RESUMO

Based on quantum identity authentication, a novel continuous variable quantum steganography protocol is proposed in this paper. It can effectively transmit deterministic secret information in the public quantum channel by taking full advantage of entanglement properties of continuous variable GHZ state. Compared with the existing quantum steganography results, this protocol has the advantages of good imperceptibility and easy implementation. Finally, the detailed performance analysis proves that the proposed protocol has not only these advantages, but also good security and information transmission efficiency, even under eavesdropping attacks, especially to the spectroscopic noise attack.

5.
Mater Sci Eng C Mater Biol Appl ; 104: 109705, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499950

RESUMO

Microfluidics-based microfibers have been widely used as bottom-up scaffolds for tissue engineering applications. Different forms of microfibers with certain thickness of shell have been developed during the past decade. Ultra-thin microfiber, as a special and promising carrier of cells, was less explored. In this work, by using the interfacial ionic interaction between sodium alginate (NaA) and chitosan (CS), a novel ultra-thin polyelectrolyte hollow microfiber with the diameter of ~200 µm and the shell thickness of 1.3 ±â€¯0.3 µm was fabricated via a microfluidic device for liver tissue engineering. The fluorescence of FITC labeled CS confirmed the inner CS layer of the fabricated microfiber and the SEM results illustrated its ultra-thin characteristic. Although there are only two layers in the ultra-thin polyelectrolyte hollow microfiber, the following cells encapsulation experiments indicated that it could bear cells loading and the hollow space of the microfibers could encapsulate sufficient number of cells for tissue engineering applications. The presence of inner CS layer in the microfiber promoted cell adhesion and ultra-thin shell characteristic facilitated the exchange of nutrient substance and O2 and thus promoted cell proliferation. HepG2 cells encapsulated in the microfibers maintained favorable viability, proliferation ability and hepatic specific functions during 10 days' culture. These results suggest that the established polyelectrolyte microfibers hold great potential applications in the field of liver tissue engineering. We believe this work will lead to the development of innovative methodologies and materials for both cell culture and biomedical application.

6.
Adv Mater ; : e1905449, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31517409

RESUMO

Biological processes and technological applications cannot work without liquid control, where versatile water droplet manipulation is a significant issue. Droplet motion is conventionally manipulated by functionalizing the target surface or by utilizing additives in the droplet, still, with uncontrolled limitation on superhydrophobic surfaces since droplets are either unable to move fast or are difficult to stop while moving. A controllable high-speed "all-in-one" no-loss droplet manipulation, that is, in-plane moving and stopping/pinning in any direction on a superhydrophobic surface, with electrostatic charging is demonstrated. The experimental results reveal that the transport speed can vary from zero to several hundreds of millimeters per second. Controlled dynamic switching between the onset moving state and the offset pinning state of a water droplet can be achieved by out-of-plane electrostatic charging. This work opens the possibility of droplet control techniques in various applications, such as combinatory chemistry, biochemical, and medical detection.

7.
Small ; : e1903320, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31402577

RESUMO

Noninvasive bioassays based on the principle of a hydrogen peroxide (H2 O2 ) cathodic reaction are highly desirable for low concentration analyte detection within biofluids since the reaction is immune to interference from oxidizable species. However, the inability to selectively reduce H2 O2 over O2 for commonly used stable catalysts (carbon or noble metals) is one of the key factors limiting their development and practical applications. Herein, catalysts that enable selective H2 O2 reduction in the presence of oxygen with fluctuating concentrations are reported. These catalysts consist of noble metal nanoparticles underneath an amorphous chromium oxide nanolayer, which inhibits O2 diffusion to the metal/oxide interface and suppresses its reduction reaction. Using these catalysts, analytes of low concentration in biofluids, including but not limited to glucose and lactate, are detected within the presence of various interferents. This work enables wide application of the cathodic detection principle and the development of reliable noninvasive bioassays.

8.
Adv Mater ; : e1904475, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31465133

RESUMO

Inkjet printing of water-based inks on superhydrophobic surfaces is important in high-resolution bioarray detection, chemical analysis, and high-performance electronic circuits and devices. Obtaining uniform spreading of a drop on a superhydrophobic surface is still a challenge. Uniform round drop spreading and high-resolution inkjet printing patterns are demonstrated on superhydrophobic surfaces without splash or rebound after high-speed impacting by introducing live-oligomeric surfactant adhesion. During impact, the live-oligomeric surfactant molecules aggregate into dynamic, wormlike micelle networks, which jam at the solid-liquid interface by entangling with the surface micro/nanostructures to pin the contact line and jam at the spreading periphery to keep the uniform spreading lamellar shape. This efficient uniform spreading of high-speed impact drops opens a promising avenue to control drop impact dynamics and achieve high-resolution printing.

9.
FEBS J ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31365784

RESUMO

A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) is a metalloproteinase known to modulate the progression of several types of tumor. However, the role played by ADAM10 in pituitary adenomas is currently unknown, and what factors orchestrate the activation of ADAM10 in this kind of tumor is also unclear. Here, we found that SRC kinase is an ADAM10-interacting partner and that SRC kinase activity is required for this interaction. As a new positive regulator promoting the shedding activity of ADAM10, SRC could compete with calmodulin 1 (CALM1) for ADAM10 binding in a mutually exclusive manner. Strikingly, the interaction between ADAM10 and CALM1 is regulated by SRC activity. Furthermore, we proved that the cytoplasmic region of ADAM10 is required for the shedding activity of ADAM10 upon SRC activation. As a proof-of-concept, we discovered that the combination of ADAM10 and SRC inhibitors can inhibit cell proliferation and migration to a great extent. Thus, our findings shed light on a novel therapeutic strategy to block the tumorigenesis and migration of pituitary adenoma.

10.
Genes Immun ; 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31435003

RESUMO

Type II innate lymphoid cells (ILC2) play a very important role in the pathogenesis of allergic asthma. This study aims to investigate whether miR-146a inhibition of asthma is related with interleukin (IL)-33 signaling path way in ILC2 and the underlying mechanisms. Asthma mice model was induced by ovalbumin. miRNA146a mimics was administrated to asthma mice or transfected to activated ILC2 purified from asthma mice lung. RT-PCR was used to detect miRNA146a level in lung tissue and ILC2. IL-5 and IL-13 levels in culture supernatant were detected by flow cytometry. Interleukin-1 receptor-associated kinase 1 (IRAK1), TNF receptor-associated factor 6 (TRAF6), signal transducer and activator of transcription 1 (STAT1) protein expression levels were detected by western blot. miR-146a directly inhibited ILC2 function and suppressed ILC2 proliferation both in vivo and in vitro. During stimulation of ILC2, miR-146a expression gradually increased with a decrease of cell proliferation. Modulation of ILC2 function by miR-146a may depend on IL-33/interleukin 1 receptor-like 1 (IL1RL1 or ST2) signaling through inhibiting IRAK1 and TRAF6.miR-146a can inhibit IRAK1 and TRAF6, downstream molecules of ST2 signal pathway, thereby negatively regulate IL-33/ST2-activated ILC2 to inhibit asthma. Targeting miR-146 maybe a novel strategy for the treatment of allergic asthma.

11.
Adv Mater ; : e1904113, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31456222

RESUMO

Excessive sweat secreted from the skin often causes undesired adhesion from wetted textiles and cold sensations. Traditional hydrophilic textiles such as cotton can absorb sweat but retain it. A hydrophobic/superhydrophilic Janus polyester/nitrocellulose textile embedded with a conical micropore array with a hydrophilic inner surface that can achieve directional liquid transport (with an ultrahigh directional water transport capability of 1246%) and maintain human body temperature (2-3 °C higher than with cotton textiles) is demonstrated. When the hydrophobic polyester layer with large opening of hydrophilic conical micropores contacts the liquid, the Janus polyester/nitrocellulose textile can pump it to the superhydrophilic nitrocellulose layer through the hydrophilic conical micropores driven by capillary force. The Janus polyester/nitrocellulose textile can weaken undesired wet adhesion and heat loss due to the removal of liquid. The water wicking and air permeability of the Janus polyester/nitrocellulose textile is comparable to those of traditional cloths. This study is valuable for designing of functional textiles with directional water transport properties for personal drying and warming applications.

12.
Nat Commun ; 10(1): 3876, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462636

RESUMO

The salinity gradient between seawater and river water is a clean energy source and an alternative solution for the increasing energy demands. A membrane-based reverse electrodialysis technique is a promising strategy to convert osmotic energy to electricity. To overcome the limits of traditional membranes with low efficiency and high resistance, nanofluidic is an emerging technique to promote osmotic energy harvesting. Here, we engineer a high-performance nanofluidic device with a hybrid membrane composed of a silk nanofibril membrane and an anodic aluminum oxide membrane. The silk nanofibril membrane, as a screening layer with condensed negative surface and nanochannels, dominates the ion transport; the anodic aluminum oxide membrane, as a supporting substrate, offers tunable channels and amphoteric groups. Thus, a nanofluidic membrane with asymmetric geometry and charge polarity is established, showing low resistance, high-performance energy conversion, and long-term stability. The system paves avenues for sustainable power generation, water purification, and desalination.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31441973

RESUMO

Extensive applications for photodetectors have led to demand for high-responsivity polarization-sensitive light detection. Inspired by the elaborate architecture of butterfly Papilio paris, a 1D nanograting bonded porous 2D photonic crystal perovskite photodetector (G-PC-PD) using a commercial DVD master and 2D crystalline colloidal arrays template was fabricated. The coupling effect from grating diffraction and reflection of the PC stopband renders the enhanced light harvesting of G-PC-PD. The porous scaffold and nanoimprinting process afford a highly crystalline perovskite film. White light responsivity and detectivity of G-PC-PD are up to 12.67 A W-1 and 3.22×1013  Jones (6∼7 times that of a pristine perovskite photodetector). The highly ordered nanograting arrays of G-PC-PD enable polarization-sensitive light detection with a rate of -0.72 nA deg-1 . This hierarchical perovskite integrated nanograting and 2D PC architecture opens a new avenue to high-performance optoelectronic devices.

14.
ACS Nano ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31465692

RESUMO

Precise and robust manipulation of air bubbles will favor intense demands from governing processes of chemical reactions to enhancing transportation efficiency in multiphase engineering systems. Inspired by the working mechanism of mucous lining in lung alveoli, the elastic liquid-infused material (eLIM) is constructed by infiltrating an interconnected porous elastomer with a low-surface-energy lining liquid. With the help of the lining liquid, the pore pressure of the interconnected channels in eLIM can be reversibly regulated under mechanical stretching, balancing the capillary pressure in the channels with diverse radii and allowing gas flow in these channels. Therefore, air bubbles could be transported in and across the eLIM, showing on-demand control on the bubble contact angle, merging and splitting in an active and precise manner. The robust manipulation strategies on air bubbles can find applications in bioreactors and many other bubble-involved processes.

15.
Clin Lab ; 65(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31414750

RESUMO

BACKGROUND: Vertigo and acute cerebral infarction (ACI) patients show similar symptoms such as dizziness and imbalance. This study was to investigate the diagnostic values of neutrophil counts and neutrophil to lymphocyte ratio (NLR) in distinguishing patients with ACI from those with vertigo. METHODS: This retrospective study was performed and data were gathered from medical records of patients with vertigo symptoms from the Department of Emergency and Neurology Clinics who were admitted to the Fourth Affiliated Hospital Zhejiang University School of Medicine between August 2017 and January 2019. Of the 173 patients with vertigo symptoms, 111 non-ACI vertigo patients (vertigo group) and 62 cases diagnosed with ACI (ACI group) were enrolled in this study. The neutrophil counts, lymphocyte counts, platelet counts, NLR, and PLT to lymphocyte ratio (PLR) within 24 hours after admission were compared between the two groups. Student's t-test of independent samples was adopted for the comparison of the mean between two groups. The neutrophil counts and NLR were evaluated by comparing the areas under the receiver operating characteristic curve (AUC) in distinguishing patients with ACI from those with vertigo. Comparison of AUC was performed using the Z-test. RESULTS: The neutrophil counts and NLR were significantly increased in the ACI group compared with the vertigo group (all p < 0.05), while there were no significant statistical differences of the lymphocyte counts, platelet counts, and PLR (all p > 0.05); moreover, AUC in distinguishing patients with ACI from those with vertigo was 0.647 (95% confidence interval (CI), 0.570 to 0.718) for neutrophil counts and 0.639 (95% CI, 0.562 to 0.710) for NLR, but there was no significant statistical difference (p > 0.05); finally, the cutoff values were 3.1 x 109/L in distinguishing patients with ACI from those with vertigo (specificity 41.44% and sensitivity 83.87%) for neutrophil counts and 2 (specificity 55.86% and sensitivity 67.74%) for NLR. CONCLUSIONS: As easy-to-obtain inflammatory biomarkers, both neutrophil counts and NLR could demonstrate diagnostic values in distinguishing between ACI and vertigo.

16.
Orthop Surg ; 11(4): 628-634, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31422584

RESUMO

OBJECTIVE: To find new clues to reduce postoperative recurrence after intralesional curettage by studying MRI and pathological features of giant tumor of bone (GCTB) boundaries. METHODS: A retrospective study was performed in the departments of orthopaedic surgery and medical imaging at our hospitals from January 2006 to August 2016. A total of 16 GCTB patients confirmed by pathology were asked to participate in the present study. The age range was from 18 to 44 years (9 women and 7 men). All patients underwent MRI examination. All patients underwent en bloc resection and complete postoperative tumor segments were obtained. Five specimens were obtained randomly at the place of the segments where the GCTB boundary showed different types on MRI. Ordinary HE staining was used for all specimens and we measured the depth of local tumor cell infiltration (240 measurements). Results were expressed as means ± standard deviation. Statistical analyses were carried out with one-way ANOVA and the Student-Newman-Keuls test. P < 0.05 was considered statistically significant. The kappa test was used to analyze the degree of agreement of observers. RESULTS: A total of 16 patients (median age 30.56 years; range, 18-44 years) with GCTB (the number of distal femurs and proximal tibias was 9 and 7, respectively) were tested. The boundaries of all GCTB cases were composed of clear boundary, relatively clear boundary, and blurred boundary in different proportions on MRI. Based on continuous observation of all MRI, all boundaries were incomplete. The kappa value between two radiologists and two pathologists was 0.91 and 0.88, respectively. The average depth of local tumor cell infiltration in the clear boundary, relatively clear boundary, and blurred boundary groups was 0.42 ± 0.11 mm, 2.85 ± 0.21 mm, and 4.83 ± 0.12 mm, respectively. There was statistical difference among the three groups (F = 17.62, P < 0.05). There was also statistical difference between each of the two groups (q-value was 8.95, 14.28, and 5.21, respectively, P < 0.05). The depth of local tumor cell infiltration with blurred boundaries on MRI was the largest and the depth with clear boundaries was the smallest. CONCLUSION: The intralesional curettage boundaries need to be expanded on the basis of different types of boundaries provided by MRI.

17.
Artif Cells Nanomed Biotechnol ; 47(1): 3231-3238, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31373232

RESUMO

RAS mutations are frequent in non-small cell lung cancer (NSCLC). However, targeting RAS or the downstream/upstream effectors, such as tyrosine kinase inhibitors (TKIs), has been proved to be difficult. Here, we found that the stemness of KRAS-mutant NSCLC cells but not the KRAS-wild type NSCLC cells was promoted by TKIs treatment, as evident by the increase of ALDH1 activity, stemness marker expression and spheroid formation ability. Notably, SHP2 activation was found in KRAS-mutant NSCLC cells with TKIs treatment, as judged by the increase of tyrosine 542 phosphorylation (pSHP2 Y542), which activates the RAS/MEK/ERK pathway. On the contrary, inhibition of MEK was followed by a SHP2 activation in KRAS-mutant NSCLC cells. Additionally, inhibition of SHP2 attenuates the enhanced stemness of KRAS-mutant NSCLC cells induced by TKIs, characterized by decreasing ALDH1 activity, stemness marker expression and spheroid formation capacity, while had little effects on cell viability. Finally, we revealed that SHP2 inhibitor increased the sensitivity of TKIs and chemotherapy, which was potentiated by MEK inhibition. Our results suggest a possibility of using a combination of SHP2 inhibitor and TKIs for KRAS-mutant NSCLC treatment.

18.
Angew Chem Int Ed Engl ; 58(36): 12574-12579, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31294908

RESUMO

Conventional photosensing devices work mainly by electron processing and transport, while visual systems in intelligence work by integrative ion/electron signals. To realize smarter photodetectors, some photoionic device or the combination of ionic and electronic devices are necessary. Now, an ion-transport-based self-powered photodetector is presented based on an asymmetric carbon nitride nanotube membrane, which can realize fast, selective, and stable light detection while being self-powered. Local charges are continuously generated at the irradiated side of the membrane, and none (fewer) at the non-irradiated side. The resulting surface charge gradient in carbon nitride nanotube will drive ion transport in the cavity, thus realizing the function of ionic photodetector. With advantages of low cost and easy fabrication process, the concept of ionic photodetectors based on carbon nitride anticipates wide applications for semiconductor biointerfaces.

19.
Angew Chem Int Ed Engl ; 58(36): 12481-12485, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31317609

RESUMO

A biomimetic conical submicrochannel (tip side ca. 400 nm) with functions of continuously tunable ion rectification and conductance based on thermoresponsive polymer layer-by-layer (LbL) self-assembly is presented. These self-assembled polymers with different layers exhibited a capability to regulate the effective channel diameter, and different ion rectifications/conductance were achieved. By controlling temperature, the conformation and wettability of the assembled polymers were reversibly transformed, thus the ion rectification/conductance could be further adjusted subtly. Owing to the synergistic effect, the ion conductance could be tuned over a wide range spanning three orders of magnitude. Moreover, the proposed system can be applied for on-demand on-off molecule delivery, which was important for disease therapy. This study opens a new door for regulating channel size according to actual demand and sensing big targets with different size with one channel.

20.
Adv Mater ; 31(36): e1807880, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31328840

RESUMO

Next-generation high-security cryptography and communication call for nondeterministic generation and efficient authentication of unclonable bit sequences. Physical unclonable functions using inherent randomness in material and device fabrication process have emerged as promising candidates for realizing one-way cryptographic systems that avoid duplication and attacks. However, previous approaches suffer from the tradeoffs between low-efficiency fabrication and complicated authentication. Here, all-photonic cryptographic primitives by solution printing of organic nanolaser arrays with size-dependent dual lasing emission are reported. The stochastic distribution of organic solution into discrete capillary bridges, triggered by high-rate solvent evaporation, on a periodic topographical template yields organic single crystals with regulated position, alignment, and random size, which ensures high entropy. Stimulated emission from different vibrational sublevels and the intrinsic self-absorption effect permit size-dependent dual-wavelength lasing emission at wavelengths of 660 and/or 720 nm, which can be efficiently encoded into quaternary cryptographic keys with high reliability. High entropy, solution-processed programming and all-photonic authentication of random organic nanolaser arrays facilitate their cryptographic implementation in secure communication with high throughput, efficiency, and low cost.

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