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1.
Mar Drugs ; 19(6)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070447

RESUMO

Six new fusarin derivatives, fusarins G-L (1-6), together with five known compounds (5-11) were isolated from the marine-derived fungus Fusarium solani 7227. The structures of the new compounds were elucidated by means of comprehensive spectroscopic methods (1D and 2D NMR, HRESIMS, ECD, and ORC) and X-ray crystallography. Compounds 5-11 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide, with IC50 values ranging from 3.6 to 32.2 µM. The structure-activity relationships of the fusarins are discussed herein.

2.
Carbohydr Polym ; 267: 118212, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119167

RESUMO

Cranberries of Stevens variety, mainly used for juice production, were processed into pomace, from which alcohol insoluble solids (AIS) were obtained. The cell wall polysaccharides were sequentially extracted from AIS, and characterized in terms of monosaccharide profile, sugar linkage and molecular weight distribution. Pectic polysaccharides represented more than 90% of the carbohydrates contained in hot buffer (HA), chelating agents (CH) and diluted alkali (DA) extracts. HA extract contained homogalacturonan with 75% being methyl esterified, and pectic arabinan with traces of pectic galactan, type II arabinogalactan and 1,4-ß-glucan. CH extract, recovered with the highest yield (11.0% w/w), was composed mainly of homogalacturonan. DA extract included homogalacturonan with 2% methyl esterification, abundant arabinan and galactans and traces of 1,4-ß-glucan. Glucomannan, xylan and xyloglucan represented 66% of the carbohydrates present in the last concentrated alkali extract (CA), the rest being pectic arabinan and galactan. High molecular weight polysaccharides (>102 kDa) were identified in all extracts.

3.
Langmuir ; 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34129778

RESUMO

Inspired by hook-and-loop fasteners, we designed a hydrogel network containing α-zirconium phosphate (ZrP) two-dimensional nanosheets with a high density of surface hydroxyl groups serving as nanopatches with numerous "hooks," while polymer chains with plentiful amine functional groups serve as "loops." Our multiscale molecular simulations confirm that both the high density of hydroxyl groups on nanosheets and the large number of amine functional groups on polymer chains are essential to achieve reversible interactions at the molecular scale, functioning as nano hook-and-loop fasteners to dissipate energy. As a result, the synthesized hydrogel possesses superior stretchability (>2100% strain), resilience to compression (>90% strain), and durability. Remarkably, the hydrogel can sustain >5000 cycles of compression with torsion in a solution mimicking synovial fluid, thus promising for potential biomedical applications such as artificial articular cartilage. This hook-and-loop model can be adopted and generalized to design a wide range of multifunctional materials with exceptional mechanical properties.

4.
Nat Nanotechnol ; 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083773

RESUMO

Flash memory has become a ubiquitous solid-state memory device widely used in portable digital devices, computers and enterprise applications. The development of the information age has demanded improvements in memory speed and retention performance. Here we demonstrate an ultrafast non-volatile flash memory based on MoS2/hBN/multilayer graphene van der Waals heterostructures, which achieves an ultrafast writing/erasing speed of 20 ns through two-triangle-barrier modified Fowler-Nordheim tunnelling. Using detailed theoretical analysis and experimental verification, we postulate that a suitable barrier height, gate coupling ratio and clean interface are the main reasons for the breakthrough writing/erasing speed of our flash memory devices. Because of its non-volatility this ultrafast flash memory could provide the foundation for the next generation of high-speed non-volatile memory.

5.
ISME J ; 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953361

RESUMO

Carbon fixation by chemoautotrophic microbes such as homoacetogens had a major impact on the transition from the inorganic to the organic world. Recent reports have shown the presence of genes for key enzymes associated with the Wood-Ljungdahl pathway (WLP) in the phylum Actinobacteria, which adds to the diversity of potential autotrophs. Here, we compiled 42 actinobacterial metagenome-assembled genomes (MAGs) from new and existing metagenomic datasets and propose three novel classes, Ca. Aquicultoria, Ca. Geothermincolia and Ca. Humimicrobiia. Most members of these classes contain genes coding for acetogenesis through the WLP, as well as a variety of hydrogenases (NiFe groups 1a and 3b-3d; FeFe group C; NiFe group 4-related hydrogenases). We show that the three classes acquired the hydrogenases independently, yet the carbon monoxide dehydrogenase/acetyl-CoA synthase complex (CODH/ACS) was apparently present in their last common ancestor and was inherited vertically. Furthermore, the Actinobacteria likely donated genes for CODH/ACS to multiple lineages within Nitrospirae, Deltaproteobacteria (Desulfobacterota), and Thermodesulfobacteria through multiple horizontal gene transfer events. Finally, we show the apparent growth of Ca. Geothermincolia and H2-dependent acetate production in hot spring enrichment cultures with or without the methanogenesis inhibitor 2-bromoethanesulfonate, which is consistent with the proposed homoacetogenic metabolism.

6.
Zhongguo Zhong Yao Za Zhi ; 46(7): 1738-1742, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33982477

RESUMO

With the process of urbanization and population aging in China, the burden of cardiovascular disease and the incidence of coronary heart disease among postmenopausal women have greatly increased. Studies have found that the incidence of coronary heart disease in postmenopausal women is closely related to the level of estrogen, but there are still difficulties of low efficiency and large side effects in current therapies. Kidney deficiency has a strong correlation with reproductive development and overall function. The clinical manifestations and characteristics of postmenopausal coronary heart disease patients conform to the pathogenesis of kidney deficiency in traditional Chinese medicine. The kidney-invigorating method has a good efficacy in treating postmenopausal coronary heart disease patients. This paper summarizes clinical and pharmacological evidences, expounds the relationship between kidney deficiency and the level of estrogen, and the pathological mechanism of the kidney-tonifying method in the treatment of coronary heart disease, and defines the clinical efficacy and advantages of the kidney-tonifying method. The method may become an effective method to prevent and treat postmenopausal coronary heart disease, and is expected to benefit patients with coronary heart disease better.


Assuntos
Doença das Coronárias , Medicamentos de Ervas Chinesas , China , Doença das Coronárias/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Estrogênios , Feminino , Humanos , Rim , Medicina Tradicional Chinesa
7.
ChemistryOpen ; 10(5): 553-559, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33945237

RESUMO

Photodecarboxylase from Chlorella variabillis (CvFAP) is one of the three known light-activated enzymes that catalyzes the decarboxylation of fatty acids into the corresponding C1-shortened alkanes. Although the substrate scope of CvFAP has been altered by protein engineering and decoy molecules, it is still limited to mono-fatty acids. Our studies demonstrate for the first time that long chain dicarboxylic acids can be converted by CvFAP. Notably, the conversion of dicarboxylic acids to alkanes still represents a chemically very challenging reaction. Herein, the light-driven enzymatic decarboxylation of dicarboxylic acids to the corresponding (C2-shortened) alkanes using CvFAP is described. A series of dicarboxylic acids is decarboxylated into alkanes in good yields by means of this approach, even for the preparative scales. Reaction pathway studies show that mono-fatty acids are formed as the intermediate products before the final release of C2-shortened alkanes. In addition, the thermostability, storage stability, and recyclability of CvFAP for decarboxylation of dicarboxylic acids are well evaluated. These results represent an advancement over the current state-of-the-art.

8.
J Agric Food Chem ; 69(20): 5774-5782, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33978404

RESUMO

Bioglycosylation is an efficient strategy to improve biological activities and physicochemical properties of natural compounds to develop structural modifications of drugs. In this study, an N555 residue was identified as a candidate for site-directed mutagenesis through sequence alignment with GTF180ΔN. Caffeic acid phenethyl ester (CAPE) was used as an acceptor substrate. Two generated mutants, N555Q and N555E, demonstrated significant specificity of distribution of products. Under identical conditions, the conversion rates of diglycoside products (CAPE-2G) generated by the N555E (80.8%) and N555Q (84.5%) mutants were 3.30- and 3.46-fold higher than those generated by the original enzyme (24.4%). The structural simulation results demonstrated that a new hydrogen bond was formed between the N555 residue and CAPE, and the N555 residue was closely related to substrate elongation. These results provide a reference for subsequent studies. Suitable mutants for transfer of diglycosides have important application potential in the food and pharmaceutical industries.


Assuntos
Álcool Feniletílico , Ácidos Cafeicos , Glucosiltransferases , Mutação , Álcool Feniletílico/análogos & derivados
9.
Structure ; 2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34043945

RESUMO

MCM8/9 is a complex involved in homologous recombination (HR) repair pathway. MCM8/9 dysfunction can cause genome instability and result in primary ovarian insufficiency (POI). However, the mechanism underlying these effects is largely unknown. Here, we report crystal structures of the N-terminal domains (NTDs) of MCM8 and MCM9, and build a ring-shaped NTD structure based on a 6.6 Å resolution cryoelectron microscopy map. This shows that the MCM8/9 complex forms a 3:3 heterohexamer in an alternating pattern. A positively charged DNA binding channel and a putative ssDNA exit pathway for fork DNA unwinding are revealed. Based on the atomic model, the potential effects of the clinical POI mutants are interpreted. Surprisingly, the zinc-finger motifs are found to be capable of binding an iron atom as well. Overall, our results provide a model for the formation of the MCM8/9 complex and provide a path for further studies.

10.
Food Chem ; 355: 129587, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33857721

RESUMO

The efficiency of laccase-catalyzed protein cross-linking can be impacted by substrate protein structure and competing reactions. In this study, chemical grafting of ferulic acid (FA) on protein surface was applied to modulate the cross-linking of two inflexible globular proteins, lysozyme (LZM) and ovalbumin (OVA). The extent of FA-grafting was positively correlated with protein cross-linking extent, and determined the molecular weight profile and structures of the cross-linked product. While laccase-catalyzed reactions (with or without free FA mediator) did not lead to evident cross-linking of the native proteins, oligomeric (up to 16.4%), polymeric (up to 30.6%) FA-LZMs and oligomeric FA-OVA (5.1-31.1%) were obtained upon the enzymatic treatments. The cross-linking on the grafted FA sites occurred mainly through the formation of 8-5'-noncyclic-dehydro-diferulic linkages. The effects of investigated cross-linking approach on the emulsifying, foaming properties and the immunoglobulin E (IgE) binding capacity of LZM and OVA were also evaluated in relation to the structural properties of cross-linked proteins.


Assuntos
Imunoglobulina E/imunologia , Lacase/metabolismo , Muramidase/imunologia , Ovalbumina/imunologia , Fenóis/química , Reações Antígeno-Anticorpo , Biocatálise , Ácidos Cumáricos/química , Reagentes para Ligações Cruzadas/química , Humanos , Peso Molecular , Muramidase/química , Ovalbumina/química , Oxirredução
11.
Biometrics ; 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33914905

RESUMO

A prominent threat to causal inference about peer effects in social science studies is the presence of homophily bias , that is, social influence between friends and families is entangled with common characteristics or underlying similarities that form close connections. Analysis of social study data has suggested that certain health conditions such as obesity and psychological states including happiness and loneliness can spread between friends and relatives. However, such analyses of peer effects or contagion effects have come under criticism because homophily bias may compromise the causal statement. We develop a regression-based approach which leverages a negative control exposure for identification and estimation of contagion effects on additive or multiplicative scales, in the presence of homophily bias. We apply our methods to evaluate the peer effect of obesity in Framingham Offspring Study.

12.
Dentomaxillofac Radiol ; : 20210030, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33835837

RESUMO

OBJECTIVE: To retrospectively analyze magnetic resonance imaging (MRI) features of various pathological subtypes of sinonasal rhabdomyosarcoma (RMS) and explore correlations between imaging features and pathological subtypes. METHODS: In total, 11 cases with embryonal, alveolar or pleomorphic sinonasal RMSs, confirmed by surgical pathology, were selected. Their characteristics and distinctive imaging features were analysed, and the correlation between pathology and imaging features was explored. RESULTS: Bone destruction was observed in all 11 cases with RMS. Expansive growth was predominant in three alveolar and three embryonal RMS cases, and creeping growth was predominant in two alveolar, two embryonal and one pleomorphic RMS cases. Signs of residual mucosa were observed in all 11 cases, and 10 cases showed involvement of multiple sinus cavities and orbital cavities. All cases exhibited mild-to-intermediate enhancement. CONCLUSION: Sinonasal RMSs have the following characteristic MRI features: ethmoid sinuses and middle nasal conchae are the prevalent sites; lesions are mainly of mild enhancement; tumours exhibit signs of residual mucosa, mild-to-intermediate enhancement and frequent orbital involvement; bone invasion and bone destruction are frequently observed; and haematogenous metastasis is not as common as lymphatic metastasis. RMSs of various pathological subtypes were not significantly distinct by imaging.

13.
Materials (Basel) ; 14(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804760

RESUMO

The interface bonding behavior between the steel tube and the concrete of concrete-filled steel tube (CFST) blended with circulating fluidized bed bottom ash (CFB-BA) was investigated in this study. A total of 8 groups of CFSTs stub columns were prepared with different dosage of CFB-BA, water-binder ratio (W/B), and interface bonding length. A series of push-out tests were carried out to acquire the data representing the interface bonding behavior. The results show that the dosage of CFB-BA has a direct effect on interface bonding behavior of CFST. CFB-BA can improve the interface bonding behavior of CFST. The highest ultimate bonding load and strength are achieved when the dosage of CFB-BA is 30%. When the dosage of CFB-BA increases to 50%, its interface bonding behavior decreases, but is still better than that of CFST without CFB-BA. W/B has a negative correlation with the interface bonding behavior of CFST. While the W/B increases, the interface bonding load and strength of CFST decreases. The increase of the interface bonding length can improve the interface bonding load, but cannot improve the interface bonding strength.

14.
Chem Commun (Camb) ; 57(31): 3816-3819, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33876130

RESUMO

A dual-aptamer based AND logic cascade circuit is activated on cell membranes in response to the receptor-aptamer binding, affording enhanced specificity for cell subtype recognition and gene silencing.

15.
Nat Prod Res ; : 1-6, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33719740

RESUMO

A new tyrosine derivative (1), and two new terezine derivatives (2 and 3) were discovered from a marine-sponge-derived fungus Phoma herbarum YG5839. Those compounds were identified by comprehensive spectroscopic analysis, and antifungal activities were conducted against Fusarium oxysporum, Fusarium graminearum, Penicillium italicum, Colletotrictum gloeosporioides and Colletotrichum musae.

16.
PLoS One ; 16(3): e0248782, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33765000

RESUMO

OBJECTIVE: Related evidences of metabolically unhealthy profile of adults with normal weight are not well characterized in the Chinese population. This is because they cannot be effectively identified by regular measurements (such as body mass index [BMI]). To overcome this gap in literature, this study aimed at investigating the association between body composition and metabolically unhealthy profile in Chinese adults with normal weight. METHODS: A total of 5427 individuals with normal-weight were recruited from 15820 people living in Ningxia Hui Autonomous Region in Northwest China. Normal-weight was defined as a BMI of 18.5-23.9 kg/m2. Metabolically unhealthy profile was assessed by the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Metabolically unhealthy normal-weight (MUHNW) profile was defined in individuals who had normal weight and at least two cardiometabolic risk factors. Generalized linear model was used to investigate the association between body composition measured by bioelectrical impedance and metabolically unhealthy profile in adults with normal-weight. RESULTS: The percentage of metabolically unhealthy profile was 35.86% in adults with normal weight. Different MUHNW distributions were found between males and females depending on age. The percentage of the MUHNW profile significantly increased in women after the age of 55, contrary to men. The association between body composition and MUHNW was affected by age and sex. The increased adiposity indices (fat mass index [FMI], visceral fat level [VFL], waist circumference [WCF]), and reduced skeletal muscle mass ratio [SMR] showed significant differences between MUHNW and metabolically healthy with normal weight (MHNW) (p < 0.05). CONCLUSION: The distribution of MUHNW differed between ages and sexes. FMI, VFL, WCF and SMR could be responsible for the MUHNW adults, providing a new insight into the potential metabolic risks for the adults with normal weight in China. This directs us in the management of the MUHNW for their early prevention.

17.
Ann Palliat Med ; 10(2): 2238-2253, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33725777

RESUMO

BACKGROUND: Abnormal microangiogenesis and microenvironmental disturbances within the Nasopharyngeal carcinoma (NPC) can exacerbate tumor hypoxia, which may increase radiotherapy resistance and thus lead to poor prognosis in NPC patients. A non-invasive imaging technique, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), which can reflect the tumor blood perfusion and angiogenesis status, was used to investigate the relationships of DCE-MRI parameters with hypoxia-inducible factor 1 alpha (HIF-1α) expression and tumor grades in NPC patients. METHODS: 42 treatment-naive patients with pathologically confirmed NPC were enrolled in this analysis. Plain magnetic resonance scans and DCE-MRI scans were performed before treatment, and post-processing was performed to calculate the relative enhancement (RE), maximum relative enhancement (MRE), maximum enhancement (ME), wash-in rate (WIR), wash-out rate (WOR), time to peak (TTP), and area under the curve (AUC). Immunohistochemistry was used to detect HIF-1α expression in electronasopharyngeal fiberoscopic specimens. The clinical grade/stage of NPC was jointly assessed by an experienced radiologist and a radiotherapist. The potential correlations of the DCE-MRI parameters with HIF-1α expression and clinical grades were analyzed. The statistical analysis was performed using SPSS 17.0 software package. RESULTS: Among DCE-MRI parameters, RE, ME, and MRE were associated with the positive expression of HIF-lα in NPC and could reflect the hypoxic status in the local microenvironment of the cancer foci in vivo. RE, ME, and MRE were significantly higher in the positive HIF-1α expression group than in the negative HIF-1α expression group (F=5.281, P=0.027; F=11.923, P=0.001; F=6.228, P=0.017). RE, ME, and MRE were significantly correlated with clinical grade (F=3.646, P=0.021; F=3.204, P=0.034, F=3.050, P=0.040) and T stage (F=6.578, P=0.001; F=3.540, P=0.023; F=4.384, P=0.010). The values of RE, MRE, and ME gradually increased as the clinical grade and T stage increased. CONCLUSIONS: DCE-MRI is a valuable imaging technique for the noninvasive evaluation of hypoxia in NPC, the development of individualized treatment protocols, and the prediction of efficacy.


Assuntos
Meios de Contraste , Neoplasias Nasofaríngeas , Humanos , Hipóxia , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Microambiente Tumoral
18.
Artigo em Inglês | MEDLINE | ID: mdl-33710104

RESUMO

PURPOSE: The purpose of this study was to evaluate the disinfection efficacy of peracetic acid disinfectant (Type III) on gastrointestinal endoscopy. METHODS: Endoscopes were disinfected, respectively, by 2% glutaraldehyde and peracetic acid disinfectant (Type III) according to the procedures stipulated by the 2016 version of "Regulation for cleaning and disinfection technique of flexible endoscope," then samples were collected through biopsy channel at the specified steps. The bacterial count and pathogenic bacteria of these samples were detected, and hepatitis B virus surface antigen, hepatitis C virus antibody, and Treponemiapallidum antibody were detected by chemiluminescent microparticle immunoassay in peracetic acid disinfectant (Type III) group. The samples from the peracetic acid disinfectant (Type III) group were collected for 5 days continuously. RESULTS: In total, 56 gastroscopes and 16 colonoscopes were disinfected by 2% glutaraldehyde (GA Group), 46 gastroscopes, and 15 colonoscopes were disinfected by peracetic acid disinfectant (Type III) (PAA Group). After disinfection, the bacterial count was significantly reduced in the 2 groups (P<0.05). In terms of the qualified rate of gastroscopes and total qualified rate, the PAA Group was better than GA Group [the qualified rate of gastroscopes: 97.83% (45/46) vs. 92.86% (52/56), P>0.05; total qualified rate: 98.36% (60/61) vs. 94.44% (68/72), P>0.05], the qualified rate of colonoscopes in the 2 groups were both 100.00% (15/15, 16/16). After disinfecting by peracetic acid disinfectant (Type III), hepatitis B virus surface antigen, anti-hepatitis C virus, and Treponemiapallidum antibody were negative. In term of colonies number detected for 5 days continuously, there was no significant difference at different collection steps (P>0.05). CONCLUSIONS: Peracetic acid disinfectant (Type III) can be well applied to clinical with meeting the standard of high-level disinfection for gastrointestinal endoscopy, and after disinfecting by peracetic acid disinfectant (Type III), there was no obvious bacterial residue in the biopsy channel.

19.
J Thromb Thrombolysis ; 51(3): 748-756, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33738769

RESUMO

To investigate the characteristics of pulmonary artery distensibility (PAD) in patients with acute pulmonary embolism (APE) and to assess whether a relationship exists between PAD and the disease severity. Clinical and radiological data of 30 APE patients who underwent retrospective electrocardiogram (ECG)-gated computed tomography pulmonary angiography (CTPA) with a definite diagnosis of APE were retrospectively reviewed in the present study, including 15 subjects in severe (SPE) group and 15 subjects in non-severe (NSPE) group. PAD and cardiac function parameters were compared between the two groups, their relationships were investigated, and receiver operating characteristic (ROC) curves were used to determine the sensitivity and specificity of the above parameters for the diagnosis of APE severity. The PAD decreased in the following order: NSPE group (6.065 ± 2.114) × 10-3 (%/mmHg), and SPE group (4.334 ± 1.777) × 10-3 (%/mmHg) (P < 0.05). All the cardiac function parameters except RA/LAdiameter showed statistically significant different values between the two groups (P < 0.05). As APE severity increased, the cardiac morphological measurements of RV/LVdiameter, RV/LVarea, RVEDV/LVEDV and RVESV/LVESV increased. There was a weak to moderate negative correlation between PAD and PAmax, PAmin, PA/AAmin, PA/AAmax, RV/LVdiameter, RV/LVarea (r = -0.393 to -0.625), that is, PAD was inversely correlated with cardiac function parameters. There was a moderate negative correlation between PAD and hemoptysis(r = -0.672). The area under the ROC curve (AUC) of PAD was 0.724, the critical value was 4.137 × 10-3  mm/Hg, and the sensitivity and specificity were 60.0% and 93.3%, respectively. PAmin showed the strongest discriminatory power to identify high-risk patients (AUC = 0.827), with the highest sensitivity of 100%, which was also achieved by RA/LAarea. The PAD obtained by retrospective ECG-gated CTPA could be an indicator to be used in the evaluation of the presence and severity of APE.

20.
ACS Appl Mater Interfaces ; 13(10): 12531-12540, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33685117

RESUMO

Dual-network conductive hydrogels have drawn wide attention in epidemic electronics such as epidemic sensors and electrodes because of their inherent low Young's modulus, high skin-compliance, and tunable mechanical strength. However, it is still full of challenges to gain a dual-network hydrogel with high stretchability, low hysteresis, and skin-adhesive performance simultaneously. Herein, to address this issue, a novel dual-network hydrogel (denoted as PAa hydrogel) with polyacrylamide as the first network and topologically entangled polydopamine as the secondary network was prepared through a facile gel-phase in situ self-polymerization and soaking treatment. Benefiting from the topological enhancement as well as the synergetic effects of hydrogen bonds and metal coordination bonds, low modulus (∼10 kPa), excellent stretchability (1090.8%), high compression (90%), negligible hysteresis (η = 0.019, energy loss coefficient), rapid recovery in seconds, and self-adhesion are obtained in the PAa hydrogels. To demonstrate their practical use, a states-independent and skin-adhesive epidemic sensor was successfully attached on human skin for motion detection. What is more, by using the hydrogel as an epidemic electrode, electromyogram signals were accurately detected and wirelessly transmitted to a smart phone. This work offers a new insight to understand the strengthening mechanism of dual network hydrogels and a design strategy for both epidemic sensors and electrodes.

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