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1.
Water Res ; 168: 115150, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606556

RESUMO

The disinfection performance of a flow-through electrode system (FES) was systematically evaluated using different carbonized (C1, C2, and C3) and corresponding graphitized (G1, G2, and G3) carbon fiber felt (CFF) electrodes. The physicochemical and electrochemical properties were characterized to identify the differences among CFFs. Graphitized CFFs (gCFFs) can achieve complete inactivation of Escherichia coli (>6 log) at the voltage of 3 V and flux of 120-3600 L/(m2 h) for high conductivity and chemical stability, while carbonized CFFs (cCFFs) only achieved around 1 log removal with obvious carbon corrosion. For the gCFFs, G1 (>6 log removal) with higher conductivity, better graphite structure, and larger surface area (related to fiber diameter and density) presented better disinfection performance at the flow rate of 30 mL/min than G2 (∼3 log) and G3(∼1 log). Furthermore, no regrowth and reactivation of bacteria occurred during the storage under visible light illumination after FES treatment. Three parallel FESs with G1 were operated continuously for one week (24 h per day, 7 days) treating the solution with an E. coli concentration ranging from 106 to 107 CFU/mL at the applied voltage of 3 V and the flow rate of 20 mL/min. No live bacteria were detected in the effluent of any of these three FESs. In-situ sampling experiments demonstrated that the inactivation of bacteria on anode was the dominant mechanism for FES treatment, which can be attributed to the sequential adsorption, direct-oxidation and desorption process on anode, instead of indirect oxidation by generating chemical oxidants. In addition, hydroxide ion generated from cathode reaction enhanced anode adsorption and inactivation of bacteria by providing alkaline environment. Combining the analysis results of material properties and disinfection performance, the gCFF-based FES was suggested to be a low-cost, high-efficiency, and safe alternative for future water disinfection.


Assuntos
Fibra de Carbono , Purificação da Água , Desinfecção , Eletrodos , Escherichia coli
2.
Opt Express ; 27(20): 27441-27458, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684511

RESUMO

Under the framework of light field, the diffusing angle and spatial location of holographic diffusor is investigated for the integral imaging based light field display. These two parameters are considered in terms of continuous light field reconstruction of the object point and blind visual spots elimination for the viewer. The concept of joint view reconstruction as well the essence of this view interpolation is analyzed theoretically, and a new phenomenon caused by the additional holographic plane called double window violation is also deduced. To the best of our knowledge, this is the first report on the quantitative analysis of the two key parameters of the holographic diffusor, which is deduced theoretically and verified experimentally.

3.
Diagn Pathol ; 14(1): 126, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699112

RESUMO

BACKGROUND: Myeloid sarcoma (MS), which represents a rare malignancy that comprises of myeloid blasts occurring at extra-medullary sites, closely correlates with the onset and relapse of acute myeloid leukemia (AML) and other hemopoietic neoplasm. Female genital system is an uncommon location of MS, with the vulvar MS being even rarer that only eight cases have been reported in English-written literature. CASE PRESENTATION: A 47-year-old woman presented with chronic ulceration on her vulva for one and a half month. Microscopic examination of incisional biopsy revealed dermal infiltration of myeloid precursor cells, which were positive for MPO, lysozyme, CD43, CD68, CD38 and CD117. Bone marrow flowcytometric analysis showed myeloblast count of 74%, which expressed CD13, CD33, CD117 and HLA-DR. A diagnosis of AML (M2 type) was made and vulvar MS was the earliest symptom. The patient achieved complete remission after chemotherapy with no evidence of recurrence in a 27-month follow-up. We reviewed the literature and identified 54 cases of Chinese patients with gynecological MS between 1999 and 2018, and discovered that in Chinese population, MS most frequently involved uterine cervix followed by the ovary and vulva, and ovarian MS onset much earlier than other sites. Remarkably, vulvar MS exhibited a high rate of concurrent AML and secondary myeloid leukemia within a short time of its occurrence. Despite its limited distribution, MS should be tackled aggressively with chemotherapy followed by allogeneic hematopoietic stem cell transplantation if the appropriate donor is available. CONCLUSIONS: Female genital MS, especially vulvar MS, should be included in the differential diagnosis of gynecological neoplasm, which will facilitate its early diagnosis and prompt management.

4.
J Synchrotron Radiat ; 26(Pt 6): 2024-2032, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721747

RESUMO

Conventional imaging methods such as magnetic resonance imaging, computed tomography and digital subtraction angiography have limited temporospatial resolutions and shortcomings like invasive angiography, potential allergy to contrast agents, and image deformation, that restrict their application in high-resolution visualization of the structure of microvessels. In this study, through comparing synchrotron radiation (SR) absorption-contrast imaging to absorption phase-contrast imaging, it was found that SR-based phase-contrast imaging could provide more detailed ultra-high-pixel images of microvascular networks than absorption phase-contrast imaging. Simultaneously, SR-based phase-contrast imaging was used to perform high-quality, multi-dimensional and multi-scale imaging of rat brain angioarchitecture. With the aid of image post-processing, high-pixel-size two-dimensional virtual slices can be obtained without sectioning. The distribution of blood supply is in accordance with the results of traditional tissue staining. Three-dimensional anatomical maps of cerebral angioarchitecture can also be acquired. Functional partitions of regions of interest are reproduced in the reconstructed rat cerebral vascular networks. Imaging analysis of the same sample can also be displayed simultaneously in two- and three-dimensional views, which provides abundant anatomical information together with parenchyma and vessels. In conclusion, SR-based phase-contrast imaging holds great promise for visualizing microstructure of microvascular networks in two- and three-dimensional perspectives during the development of neurovascular diseases.

5.
Int J Nanomedicine ; 14: 6799-6812, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31692522

RESUMO

Background: Photodynamic therapy (PDT), a clinical anticancer therapeutic modality, has a long history in clinical cancer treatments since the 1970s. However, PDT has not been widely used largely because of metabolic problems and off-target phototoxicities of the current clinical photosensitizers. Purpose: The objective of the study is to develop a high-efficiency and high-specificity carrier to precisely deliver photosensitizers to tumor sites, aiming at addressing metabolic problems, as well as the systemic damages current clinical photosensitizers are known to cause. Methods: We synthesized a polydopamine (PDA)-based carrier with the modification of folic acid (FA), which is to target the overexpressed folate receptors on tumor surfaces. We used this carrier to load a cationic phthalocyanine-type photosensitizer (Pc) and generated a PDA-FA-Pc nanomedicine. We determined the antitumor effects and the specificity to tumor cell lines in vitro. In addition, we established human cancer-xenografted mice models to evaluate the tumor-targeting property and anticancer efficacies in vivo. Results: Our PDA-FA-Pc nanomedicine demonstrated a high stability in normal physiological conditions, however, could specifically release photosensitizers in acidic conditions, eg, tumor microenvironment and lysosomes in cancer cells. Additionally, PDA-FA-Pc nanomedicine demonstrated a much higher cellular uptake and phototoxicity in cancer cell lines than in healthy cell lines. Moreover, the in vivo imaging data indicated excellent tumor-targeting properties of PDA-FA-Pc nanomedicine in human cancer-xenografted mice. Lastly, PDA-FA-Pc nanomedicine was found to significantly suppress tumor growth within two human cancer-xenografted mice models. Conclusion: Our current study not only demonstrates PDA-FA-Pc nanomedicine as a highly potent and specific anticancer agent, but also suggests a strategy to address the metabolic and specificity problems of clinical photosensitizers.

6.
J Med Internet Res ; 21(11): e16942, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697641

RESUMO

[This corrects the article DOI: 10.2196/14484.].

7.
J Biomater Sci Polym Ed ; : 1-18, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31724490

RESUMO

Biological modifications of the silk fibroin (silk) material have broad applications in textiles, biomedical materials and other industrial materials. It is economical to incorporate nanoparticles to the biosynthesis of silk fibroin by adding them to silkworm larval diets. This strategy may result in the rapid stable production of modified silk. Glucose-coated silver nanoparticles (AgNPs) were used to improve the AgNPs' biocompatibility, and the AgNPs were efficiently incorporated into silk by feeding. Larvae fed with AgNPs produced silk with significantly improved antibacterial properties and altered silk secondary structures. Both positive and negative effects on the growth and synthesis of silk proteins were observed after different AgNPs doses. Larvae feeding with low concentration of 0.02% and medium 0.20% AgNPs have greater transfer efficiencies of AgNPs to silk compared with feeding high concentration of 2.00% AgNPs. In addition, the elongation and tensile strength of the produced silk fibers were also significantly increased, with greater mammalian cell compatibility. The appropriate AgNPs concentration in the diet of silkworms can promote the synthesis of silk proteins, enhance their mechanical properties, improve their antibacterial property and inhibit the presence of Gram-negative bacteria.

8.
J Ethnopharmacol ; : 112405, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31743766

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Chinese Herbal Prescription JieZe-1(JZ-1), added and subtracted from Yihuang Decoction, a famous formula in the 12th year of Kangxi in the Qing Dynasty, has a clear effect on Genital Herpes (GH) and no obvious adverse reactions occur clinically. JZ-1 also has preventive and therapeutic effects on Trichomonas vaginitis, Candida albicans vaginitis and GH in vitro and in vivo experiments. AIM OF STUDY: The effect and mechanism of JZ-1 on anti-herpes simplex virus type 2(HSV-2) in vitro, focusing on adhesion and penetration stage were investigated. MATERIALS AND METHODS: A model of HSV-2 infection of VK2/E6E7 was developed. In order to explore JZ-1's anti-HSV-2 effect in vitro, cell morphology, ultrastructural pathology, cell viability and expression of viral glycoprotein D (gD) were assessed at 6 h, 12 h, 18 h, and 24 h of JZ-1 treatment. Then we measured the exact time required for adhesion and penetration of HSV-2 into VK2/E6E7 among a series of times at room temperature and under temperature control techniques. We treated VK2/E6E7 with JZ-1, penciclovir, or berberine and explored the mechanism of JZ-1 in blocking HSV-2 adhesion and penetration of host cells by assessing the cell ultrastructural pathology, viability, viral proteins gB, gD, VP16, ICP5, and ICP4 and host cell proteins HVEM, Nectin-1, and Nectin-2. RESULTS: HSV-2 can fully adhered and penetrated into VK/E6E7 within 5 min at room temperature while it took 60mins under temperature control techniques. JZ-1 and penciclovir showed significant anti-HSV-2 effects, with improved host cell morphologies and increased host cell viabilities observed after treatment for 24 h. The anti-HSV-2 effect of JZ-1 can be detected after treatment for 6 h while that of penciclovir was not obvious until treatment for 12 h. JZ-1 showed distinct effects on HSV-2 adhesion and penetration stage by significantly reducing the expression of viral proteins gB, gD, VP16, ICP5, and ICP4, improving cell morphology and increasing cell viability. However, these effects were not exerted via downregulated expression of membrane fusion-related proteins such as HVEM, Nectin-1, or Nectin-2. The specific anti-HSV-2 mechanisms of JZ-1 need to be further explored. CONCLUSION: The anti-HSV-2 effect of JZ-1 was superior to that of penciclovir and berberine in vitro, and was mainly mediated by enhancing host cell defense and blocking adhesion and penetration of HSV-2.

9.
J Am Chem Soc ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31707782

RESUMO

Multivariate metal-organic frameworks (MTV-MOFs) incorporating multiple chemical functionalities within single-phase crystalline materials show superior properties that arise from synergistic effects. Herein, we report an efficient and versatile method for the growth of highly oriented multivariate surface-attached MOFs (MTV-SURMOFs) by the combination of the liquid-epitaxial growth method (LPE) and the mixed-linker strategy. Twenty-six MTV-SURMOFs of the [M2L2P] type with a maximum of five different dicarboxylate linkers (L) were deposited onto suitably functionalized surfaces. Systematic studies by infrared reflection absorption (IRRA) spectroscopy and surface XRD provide evidence for the formation of highly oriented MTV-SURMOFs. Interestingly, the pKa's of the dicarboxylate linkers play a crucial role for the orientational quality of the MTV-SURMOFs. In addition, benzene uptake experiments showed that the MTV-SURMOFs exhibit up to 2.6 times higher adsorption capacity as compared to the single-linker SURMOFs, demonstrating the synergistic effects in these surface systems.

10.
J Colloid Interface Sci ; 560: 293-302, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31670102

RESUMO

Hierarchical copper sulfide/bismuth tungstate (CuS/Bi2WO6) p-n junction with two-dimensional (2D) interfacial coupling were prepared through a two-step hydrothermal method. The as-prepared samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, diffuse reflectance spectroscopy, photoluminescence spectroscopy, photocurrent and electrochemical impedance spectroscopy. CuS nanoplates anchored on the surface of hierarchical Bi2WO6 microspheres consisting of Bi2WO6 nanosheets to form a CuS/Bi2WO6 p-n junction photocatalyst. The photocatalytic activity of glyphosate degradation over CuS/Bi2WO6 under 44 W light-emitting diode (LED) light irradiation (λ > 400 nm) was investigated. The results indicate that the CuS/Bi2WO6 heterojunctions display higher photocatalytic activity than pure CuS and Bi2WO6. The improved photocatalytic activity of the CuS/Bi2WO6 heterostructures can be attributed to strong visible light absorption and enhanced separation of photogenerated charge carriers by the internal electric field near the interface of the p-n junction. In addition, the CuS/Bi2WO6 p-n junction photocatalysts consisting of nanosheets are beneficial for the transport of photoexcited charge carriers, thus resulting in the increase of the photocatalytic activity of glyphosate degradation. This work provides the new avenue for the development and design p-n junction materials for photocatalytic applications.

11.
Macromol Biosci ; : e1900301, 2019 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-31762196

RESUMO

In this work, dual-mode antibacterial conjugated polymer nanoparticles (DMCPNs) combined with photothermal therapy (PTT) and photodynamic therapy (PDT) are designed and explored for efficient killing of ampicillin-resistant Escherichia coli (Ampr E. coli). The DMCPNs are self-assembled into nanoparticles with a size of 50.4 ± 0.6 nm by co-precipitation method using the photothermal agent poly(diketopyrrolopyrrole-thienothiophene) (PDPPTT) and the photosensitizer poly[2-methoxy-5-((2-ethylhexyl)oxy)-p-phenylenevinylene] (MEH-PPV) in the presence of poly(styrene-co-maleic anhydride) which makes nanoparticles disperse well in water via hydrophobic interactions. Thus, DMCPNs simultaneously possess photothermal effect and the ability of sensitizing oxygen in the surrounding to generate reactive oxygen species upon the illumination of light, which could easily damage resistant bacteria. Under combined irradiation of near-infrared light (550 mW cm-2 , 5 min) and white light (65 mW cm-2 , 5 min), DMCPNs with a concentration of 9.6 × 10-4 µm could reach a 93% inhibition rate against Ampr E. coli, which is higher than the efficiency treated by PTT or PDT alone. The dual-mode nanoparticles provide potential for treating pathogenic infections induced by resistant microorganisms in clinic.

12.
Sci Transl Med ; 11(519)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31748231

RESUMO

The paucity of selective agonists for TWIK-related acid-sensitive K+ 3 (TASK-3) channel, a member of two-pore domain K+ (K2P) channels, has contributed to our limited understanding of its biological functions. By targeting a druggable transmembrane cavity using a structure-based drug design approach, we discovered a biguanide compound, CHET3, as a highly selective allosteric activator for TASK-3-containing K2P channels, including TASK-3 homomers and TASK-3/TASK-1 heteromers. CHET3 displayed potent analgesic effects in vivo in a variety of acute and chronic pain models in rodents that could be abolished pharmacologically or by genetic ablation of TASK-3. We further found that TASK-3-containing channels anatomically define a unique population of small-sized, transient receptor potential cation channel subfamily M member 8 (TRPM8)-, transient receptor potential cation channel subfamily V member 1 (TRPV1)-, or tyrosine hydroxylase (TH)-positive nociceptive sensory neurons and functionally regulate their membrane excitability, supporting CHET3 analgesic effects in thermal hyperalgesia and mechanical allodynia under chronic pain. Overall, our proof-of-concept study reveals TASK-3-containing K2P channels as a druggable target for treating pain.

13.
Plant Cell ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732703

RESUMO

C2H2-type zinc finger proteins play positive roles in root hair growth and development by regulating their target genes. However, little is known about their potential negative roles in root hair initiation and elongation. Here we show that the C2H2-type zinc finger protein AtZP1, which contains an EAR motif, negatively regulates Arabidopsis thaliana root hair initiation and elongation. Our results demonstrate that AtZP1 is highly expressed in root hairs and that AtZP1 inhibits transcriptional activity during root hair development. Plants overexpressing AtZP1 lacked root hairs, while loss-of-function mutants had longer and more numerous root hairs than wild type. Transcriptome analysis indicated that AtZP1 downregulates genes encoding bHLH transcription factors associated with root hair cell differentiation and elongation. Mutation or deletion of the EAR motif significantly reduced the inhibitory activity of AtZP1. Chromatin immunoprecipitation (ChIP) assays, AtZP1:GR induction experiments, electrophoretic mobility shift assays (EMSAs), and yeast one-hybrid assays showed that AtZP1 directly targets the promoters of bHLH transcription factor genes, including the key root hair initiation gene RHD6 and root hair elongation genes RSL2 and RSL4, to suppress root hair development. Our findings suggest that AtZP1 functions downstream of GL2 to negatively regulate root hair initiation and elongation, by suppressing RHD6, RSL4, and RSL2 transcription via the GL2/ZP1/RSL pathway.

14.
Mol Cancer Ther ; 18(11): 1909-1915, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31676542

RESUMO

Despite the recent approval of immune-modulatory agents, EGFR inhibition continues to be a cornerstone in the management of squamous cell carcinoma of the head and neck (SCCHN) namely in combination with radiotherapy in the treatment of locoregionally advanced disease as well as in platinum-sensitive recurrent or metastatic disease in the first-line setting. Importantly, recent evidence has emerged supporting also an immune-modulatory effect of EGFR inhibition, and interest has now focused on utilizing these effects in the current treatment approaches for SCCHN. In this report, we review the rationale and evidence supporting the forging of this new alliance in optimizing the treatment of SCCHN.

16.
Nucleic Acids Res ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31624841

RESUMO

To date, large amounts of genomic and phenotypic data have been accumulated in the fields of crop genetics and genomic research, and the data are increasing very quickly. However, the bottleneck to using big data in breeding is integrating the data and developing tools for revealing the relationship between genotypes and phenotypes. Here, we report a rice sub-database of an integrated omics knowledgebase (MBKbase-rice, www.mbkbase.org/rice), which integrates rice germplasm information, multiple reference genomes with a united set of gene loci, population sequencing data, phenotypic data, known alleles and gene expression data. In addition to basic data search functions, MBKbase provides advanced web tools for genotype searches at the population level and for visually displaying the relationship between genotypes and phenotypes. Furthermore, the database also provides online tools for comparing two samples by their genotypes and finding target germplasms by genotype or phenotype information, as well as for analyzing the user submitted SNP or sequence data to find important alleles in the germplasm. A soybean sub-database is planned for release in 3 months and wheat and maize will be added in 1-2 years. The data and tools integrated in MBKbase will facilitate research in crop functional genomics and molecular breeding.

17.
J Phys Chem Lett ; 10(21): 6518-6524, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31596089

RESUMO

A unique flexible NiFe2O4 hollow sphere@S/rGO-CNT (NiFe2O4@S/C) cathode was rationally designed and synthesized to tackle the issues of lithium-sulfur batteries. In this strategy, the introduced rGO and CNTs offer a flexible and conductive skeleton to facilitate the transport of electrons and/or ions and a physical barrier to confine polysulfides. Furthermore, as an efficient sulfur host, NiFe2O4 hollow spheres can further absorb the soluble polysulfides by strong chemical interaction due to their intrinsic polarity and also serve as a catalyst to promote the redox kinetics of polysulfide conversion. Benefiting from the synergism of the physical confinement, polar chemical adsorption, and catalytic conversion, the as-prepared flexible NiFe2O4@S/C electrode delivers a high initial capacity of 1193 mAh g-1 at 100 mA g-1 and excellent long-term cycling stability up to 500 cycles with a low decay rate of 0.059% per cycle at 500 mA g-1.

18.
Nanoscale ; 11(43): 20968-20976, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660559

RESUMO

3D structures assembled from multiple components have attracted increasing research interest based on their enriched functionalities and broadened applications. Here, we report a bottom-up strategy to fabricate 3D halos through the co-assembly of Fe3O4 and Au nanoparticles (NPs). Typically, Fe3O4 NPs assemble into a 3D core (size around 500 nm) with simultaneous growth of Au NPs on the 3D surface during the assembly process. As a general approach, a variety of 3D halos were fabricated from the co-assembly of Fe3O4 and Au NPs of different sizes and shapes. To demonstrate the advantages of these 3D halo structures, their catalytic activity to mimic natural enzymes was investigated. Compared with Fe3O4 NP building blocks, enhanced catalytic efficiency was achieved by the 3D halos. In addition, the optical behavior of the 3D halos was simulated using a three-dimensional finite-difference time-domain (3D-FDTD) method. As shown in the results, the 3D halos attached to 90 nm Au NPs could absorb more incident light owing to high electric field intensities, making these structures promising for applications in energy harvesting and detection-related fields.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31603623

RESUMO

The synthesis of hydrophilic lanthanide-doped nanocrystals (Ln3+ -NCs) with molecular recognition ability for bioimaging currently remains a challenge. Herein, we present an effective strategy to circumvent this bottleneck by encapsulating Ln3+ -NCs in graphene oxide (NCs@GO). Monodisperse NCs@GO was prepared by optimizing GO size and core-shell structure of NaYF4 :Yb,Er@NaYF4 , thus combining the intense visible/near-infrared II (NIR-II) luminescence of NCs and the unique surface properties and biomedical functions of GO. Such nanostructures not only feature broad solvent dispersibility, efficient cell uptake, and excellent biocompatibility but also enable further modifications with various agents such as DNA, proteins, or nanoparticles without tedious procedures. Moreover, we demonstrate in proof-of-concept experiments that NCs@GO can realize simultaneous intracellular tracking and microRNA-21 visualization, as well as highly sensitive in vivo tumor-targeted NIR-II imaging at 1525 nm.

20.
ACS Appl Mater Interfaces ; 11(44): 41659-41667, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31584262

RESUMO

The development of hydrogels with excellent mechanical properties is highly desirable in both fundamental studies and practical applications. But it is difficult to construct hydrogels that are both tough and stiff at the same time as these properties often contradict each other. Here, we report a facile and efficient method for producing ultrastiff and tough poly(N-isopropylacrylamide) (PNIPAM)/clay plastic-like hydrogels (PHs) by immersing PNIPAM/clay hydrogel into NaCl aqueous solution. The optimized PH-2-6 presented superior strength, modulus, and toughness (4.1 ± 0.2 MPa, 41.6 ± 8 MPa, and 15.85 ± 0.8 MJ m-3, respectively). The unique mechanical properties are attributed to the synergistic effect of the osmotic pressure and the strong affinity between Na+ ion and the PNIPAM chain, which lead to a high degree of PNIPAM chain entanglement and fixing. Note that the PHs were molded into any required shape under an applied force, and retained permanently their shapes even if the load was removed, thus displaying typical plasticity. However, the deformed PHs could return to their original size and softness of hydrogel when immersed in pure water, which is a kind of shape-memory effect. The reversible conversion of elasticity and plasticity and shape memory arise from a kind of dynamic physical across-linking of Na+ and PNIPAM molecular chains, which could exist in the salt aqueous and disintegrate in water reversibly. Moreover, the mechanical properties of hydrogel can be tuned by adjusting the salt concentration and immersion time. The facile strategy may provide further avenue in developing hydrogels with such versatile dynamic behaviors to expand their applications.

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