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1.
Cell Rep ; 35(5): 109097, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33951436

RESUMEN

Cardiac cells generate and amplify force in the context of cardiac load, yet the membranous sheath enclosing the muscle fibers-the sarcolemma-does not experience displacement. That the sarcolemma sustains beat-to-beat pressure changes without experiencing significant distortion is a muscle-contraction paradox. Here, we report that an elastic element-the motor protein prestin (Slc26a5)-serves to amplify actin-myosin force generation in mouse and human cardiac myocytes, accounting partly for the nonlinear capacitance of cardiomyocytes. The functional significance of prestin is underpinned by significant alterations of cardiac contractility in Prestin-knockout mice. Prestin was previously considered exclusive to the inner ear's outer hair cells; however, our results show that prestin serves a broader cellular motor function.

2.
Artículo en Inglés | MEDLINE | ID: mdl-33954430

RESUMEN

Alzheimer's disease (AD) is one of the major life-threatening diseases for the elderly because neither pathogenesis nor effective treatment is available. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) has been shown to reduce the cell-damaging aldehydes in response to reactive oxygen species (ROS). However, whether it plays a role in AD remains elusive. In the present study, we found that ALDH2 overexpression significantly improved the cognitive function of the AD mouse. Behavioral analyses of ALDH2-overexpressing APP/PS1 AD mice showed that the learning and cognitive abilities were significantly higher in these mice than in the control group APP/PS1 mice. Further open-field behavior experiments showed the same results. At the cellular level, ALDH2 protects nerve cells. HT22 cells were challenged with Aß to establish an AD cell model, in the presence or absence of the ALDH2 activator Alda-1 and ALDH2 inhibitor Daidzin. Incubation with 50 µM Aß for 24 h significantly reduced HT22 cell survival and cell viability, the effects of which were attenuated by the ALDH2 activator Alda-1 (50 µM). Aß challenge promoted apoptosis and upregulated caspase3 level but suppressed Bcl-2 level, and the upregulated caspase3 level was reversed by the ALDH-2 agonist Alda-1. Aß-induced clonal ball abnormal was reversed by Alda-1. Aß altered the mitochondria geometry evidenced by vacuolar degeneration and membrane rupture, whereas Alda-1 changed the Aß-induced mitochondria geometry anomalies. Moreover, superoxide anion and toxic 4-hydroxy-nonanal (4-HNE) and ROS increased by Aß challenge were reversed by Alda-1. Meanwhile, Aß-induced ATP reduction was reversed by Alda-1. Taken together, ALDH2 overexpression significantly improves the cognitive function of the AD mice. Furthermore, our results suggested that ALDH2 protects against Aß hippocampal neuronal toxicity possibly through alleviating toxic aldehydes and ROS, as well as increasing ATP production to preserve mitochondrial integrity and reduce neuronal apoptosis.

3.
J Mol Med (Berl) ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33954835

RESUMEN

Despite recent therapeutic breakthroughs, advanced and/or recurrent endometrial cancer still poses a significant health burden globally. While immunotherapy can theoretically lead to durable responses, the benefits to patients remain limited. In an effort to identify novel immunotherapeutic targets, we specifically focused on the potential role of nucleophosmin (NPM, also known as B23) - a nucleolar phosphoprotein involved in tumorigenesis - in cancer immune evasion. Expression profiling with oligonucleotide microarrays was conducted to identify differentially expressed genes in NPM/B23-silenced endometrial cancer cells. CD24 - a heat-stable antigen commonly overexpressed in solid tumors and a target for cancer immunotherapy - was identified as one of the key NPM/B23-regulated molecules. We found that NPM/B23 was capable of inducing CD24 expression, with the Sp1 binding site in the CD24 promoter being essential for NPM/B23-mediated transcriptional activation. Interestingly, NPM/B23 silencing in endometrial cancer cells enhanced phagocytic removal by macrophages through a decreased exposure of CD24 on the cell surface. Conversely, restoration of CD24 expression in NPM/B23-silenced endometrial cancer cells inhibited macrophage-mediated phagocytosis. These results indicate that NPM/B23-driven CD24 overexpression enables endometrial cancer cells to evade from phagocytosis. We further suggest that CD24 may serve as a novel target for endometrial cancer immunotherapy. KEY MESSAGES: NPM/B23 induced CD24 expression in endometrial tumorigenesis. Sp1 binding site in the CD24 promoter is essential for the activation. NPM/B23 silencing enhanced phagocytosis by macrophages through decrease of CD24 on cancer cells. Restoration of CD24 expression in NPM/B23-silenced cancer cells inhibited macrophage-mediated phagocytosis.

4.
Artículo en Inglés | MEDLINE | ID: mdl-33955729

RESUMEN

This work demonstrated the enhanced photodegradation (PD) resulting from Co-rich doping of ZnO nanowire (NW) surfaces (Co2+/ZnO NWs) prepared by combining Co sputtering on ZnO NWs and immersion in deionized water to exploit the hydrophilic-hydrophobic transitions on the ZnO surfaces resulting from Co atom diffusion. Because of the controllable spin-dependent density of states (DOS) induced by Co2+, the PD of methylene blue dye can be enhanced by approximately 90% (when compared with bare ZnO NWs) by using a conventional permanent magnet with a relatively low magnetic field strength of approximately 0.15 T. The reliability of spin polarization-modulation attained through surface doping, based on the magnetic response observed from X-ray absorption measurements and magnetic circular dichroism, provides an opportunity to create highly efficient catalysts by engineering surfaces and tailoring their spin-dependent DOS.

5.
Invest Ophthalmol Vis Sci ; 62(6): 9, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33956051

RESUMEN

Purpose: Glaucoma remains a poorly understood disease, and identifying biomarkers for early diagnosis is critical to reducing the risk of glaucoma-related visual impairment and blindness. The aim of this review is to provide current metabolic profiles for glaucoma through a summary and analysis of reported metabolites associated with glaucoma. Methods: We searched PubMed and Web of Science for metabolomics studies of humans on glaucoma published before November 11, 2020. Studies were included if they assessed the biomarkers of any types of glaucoma and performed mass spectrometry-based or nuclear magnetic resonance-based metabolomics approach. Pathway enrichment analysis and topology analysis were performed to generate a global view of metabolic signatures related to glaucoma using the MetaboAnalyst 3.0. Results: In total, 18 articles were included in this review, among which 13 studies were focused on open-angle glaucoma (OAG). Seventeen metabolites related to OAG were repeatedly identified, including seven amino acids (arginine, glycine, alanine, lysine, methionine, phenylalanine, tyrosine), two phosphatidylcholine (PC aa C34:2, PC aa C36:4), three complements (acetylcarnitine, propionylcarnitine, butyrylcarnitine), carnitine, glutamine, hypoxanthine, spermine, and spermidine. The pathway analysis implied a major role of amino metabolism in OAG pathophysiology and revealed the metabolic characteristics between different biological samples. Conclusions: In this review, we summarize existing metabolomic studies related to glaucoma biomarker identification and point out a series of metabolic disorders in OAG patients, providing information on the molecular mechanism changes in glaucoma. Additional studies are needed to validate existing findings, and future research will need to explore the potential overlap between different biological fluids.

7.
Ecotoxicol Environ Saf ; 218: 112267, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33932652

RESUMEN

The removal characteristics of antibiotic resistance genes and mobile genetic elements from livestock wastewater (dominated by quinolone antibiotics) treated with MFC were evaluated by High-throughput quantitative (HT-qPCR). The results showed that 144 ARGs and 8 MEGs were detected in the livestock wastewater. After MFC treatment, the number of AGRs decreased as a whole, and the relative abundance of macrolide-lincosamide-streptogramin group B (MLSB) and aminoglycosider decreased by 62.7% and 92.9%, respectively. MGEs decreased by 57.3% and multidrug genes decreased by 90%. After MFC treatment, the absolute abundance of tetracycline in raw sewage decreased by two orders of magnitude from 5.8 × 105 copies L-1 to 5.1.× 103 copies L-1. However, MFC was less efficient in the removal of vancomycin and beta-lactamase genes. It was also found that chloramphenicol resistance genes slightly increased. Illumina sequencing showed that Syntrophobacterales and Synergistales were predominant in MFCs. Desulfovibrio was resistant to high concentration of moxifloxacin hydrochloride. The removal efficiency of MFC for moxifloxacin hydrochloride at a concentration of 5 mg L-1 was 86.55%. The maximum power density and coulomb efficiency were 109.3 mV·cm-3 and 41.97%, respectively. With the increase of antibiotic concentration, the sewage treatment efficiency and electrical performance were inhibited. This study shows that untreated livestock wastewater had a great risk of gene horizontal transfer. Although MFC had limited treatment capacity for high-concentration quinolone wastewater, it is an effective method to reduce ARGs and the risk of horizontal gene transfer.

8.
Aging (Albany NY) ; 132021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33946042

RESUMEN

We constructed a radiomics-clinical model to predict intraventricular hemorrhage (IVH) growth after spontaneous intracerebral hematoma. The model was developed using a training cohort (N=626) and validated with an independent testing cohort (N=270). Radiomics features and clinical predictors were selected using the least absolute shrinkage and selection operator (LASSO) method and multivariate analysis. The radiomics score (Rad-score) was calculated through linear combination of selected features multiplied by their respective LASSO coefficients. The support vector machine (SVM) method was used to construct the model. IVH growth was experienced by 13.4% and 13.7% of patients in the training and testing cohorts, respectively. The Rad-score was associated with severe IVH and poor outcome. Independent predictors of IVH growth included hypercholesterolemia (odds ratio [OR], 0.12 [95%CI, 0.02-0.90]; p=0.039), baseline Graeb score (OR, 1.26 [95%CI, 1.16-1.36]; p<0.001), time to initial CT (OR, 0.70 [95%CI, 0.58-0.86]; p<0.001), international normalized ratio (OR, 4.27 [95%CI, 1.40, 13.0]; p=0.011), and Rad-score (OR, 2.3 [95%CI, 1.6-3.3]; p<0.001). In the training cohort, the model achieved an AUC of 0.78, sensitivity of 0.83, and specificity of 0.66. In the testing cohort, AUC, sensitivity, and specificity were 0.71, 0.81, and 0.64, respectively. This radiomics-clinical model thus has the potential to predict IVH growth.

9.
J Sci Food Agric ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33949697

RESUMEN

BACKGROUND: Shiitake mushroom is one of the most popular delicious vegetables, but fresh shiitake mushroom has short shelf life due to biochemical degradation. Drying can prolong the shelf life of mushroom. Additionally, application of cold plasma pretreatments (CPT) before drying can preserve the product quality, processing cost, and nutritional values. Therefore, we aimed to explore the effect of cold plasma pretreated hot-air drying at 50, 60, and 70 °C on the physicochemical characteristics, nutritional values, and antioxidant activity of shiitake mushroom. RESULTS: In the result, SEM micrographs showed that CPT induced the surface modification of fresh shiitake (such as cellular disarrangement, cellular shrinkages, disruption or break down of cell walls, and intracellular spaces and cavities) and facilitate the rapid drying than control samples. Furthermore, CPT improved the powder qualities (bulk density, water retention, and swelling index) and preserved higher nutritional attributes (sugars, vitamins, phenolic acids contents, and antioxidant activity) than control groups. CONCLUSION: Conclusively, CPT could be a suitable alternative technique for improving drying characteristics and preserving nutritional attributes of agro-based products. This article is protected by copyright. All rights reserved.

10.
Head Neck ; 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33949716

RESUMEN

This meta-analysis evaluates whether near-infrared autofluorescence (NIRAF) imaging reduces the risk of hypocalcemia after total thyroidectomy. A systematic literature search in PubMed, EMBASE, Web of Science, and Cochrane Library for studies from June 2011 to January 2021 comparing total thyroidectomy with NIRAF and conventional surgery (naked eye). Six eligible studies involving 2180 patients were included. The prevalence of transient hypocalcemia was 8.11% (40/493) and 25.19% (425/1687) in the NIRAF and naked eye groups (p < 0.0001), respectively. The prevalence of permanent hypocalcemia was 0% (0/493) and 2.19% (37/1687) in the NIRAF and naked eye groups (p = 0.05), respectively. NIRAF reduces the risk of transient hypocalcemia and may possibly lower the rate of permanent hypocalcemia. Nonetheless, further studies are needed to verify our results and evaluate the cost-effectiveness of NIRAF in real-world clinical practice.

11.
Nanotoxicology ; : 1-18, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33961538

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is the leading hepatic manifestation of metabolic syndrome worldwide, and is clinically accompanied by iron overload. As the increasing application of iron oxide nanoparticles (IONPs) on the imaging and diagnosis in NAFLD, the potential hepatic effect and mechanism of IONPs on NAFLD should be well studied. Here, we demonstrate that carboxyl-modified (COOH-IONPs) and amino-coated IONPs (NH2-IONPs) exhibit no significant hepatic toxicity in normal mice at the clinical injection dose, but aggravate SREBP-1c-mediated de novo lipogenesis (DNL) in the livers of mice with NAFLD induced by high-fat diet (HFD) and in HepG2 cells incubated with oleic acid (OA), especially in those treated by the positive NH2-IONPs. In the present study, mice receiving IONPs for 7 day show mild iron overload in the liver and exhibit enhanced hepatic inflammation in NAFLD. The BMP-SMAD pathway is initiated by hepatic iron overload and is aggravated in NAFLD. In conclusion, BMP-SMAD-mediated hepatic iron overload aggravated lipid accumulation in the liver and hepatic inflammatory responses, implying that effective measures in addition to hepatic iron overload are needed for individuals at the risk of IONPs in NAFLD.

12.
J Hepatol ; 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33961940

RESUMEN

BACKGROUND & AIMS: Acute viral hepatitis (AVH) represents an important global health problem; however, the progress in understanding AVH is limited because of the priority of combating persistent hepatitis B (HBV) and C (HCV) virus infections. Therefore, an improved understanding of the burden of AVH is required to help design strategies for global intervention. METHODS: Data of four major AVH types, including acute hepatitis A (AHA), AHB, AHC, and AHE, excluding AHD, were collected by the Global Burden of Disease (GBD) 2019 database. Age-standardized incidence rates and disability-adjusted life years (DALYs) rates of AVH were extracted from GBD 2019 and stratified by sex, level of socio-demographic index (SDI), country, and territory. The association between the burden of AVH and socioeconomic development status, as represented by the SDI, was described. RESULTS: In 2019, there was an age-standardized incidence rate of 3615.9 (95% CI 3360.5-3888.3) and an age-standardized DALYs rate of 58.0 (47.3-70.0) per 100,000 person-years, in terms of four major AVH. Among the major AVH, acute hepatitis A caused the heaviest burden. There was a significant downward trend in age-standardized DALYs rates caused by major incidences of AVH between 1990 and 2019. In 2019, regions or countries located in West and Central Africa exhibited the highest age-standardized incidence rates of four major AVH. These rates were stratified by SDI: high SDI and high-middle SDI locations recorded the lowest incidence and DALYs rates of AVH, whereas the low-middle SDI and low SDI locations showed the highest burden of AVH. CONCLUSIONS: The socioeconomic development status and burden of AVH are associated. Therefore, the GBD 2019 data are valuable for policymakers to implement cost-effective interventions for AVH. LAY SUMMARY: Negative association of socioeconomic development status with burden of acute viral hepatitis was identified. Lowest burden of acute viral hepatitis noted for rich countries whereas highest burden of acute viral hepatitis noted for poor countries.

13.
Environ Pollut ; 285: 117196, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33962308

RESUMEN

This research aims to study the wet torrefaction (WT) and saccharification of sorghum distillery residue (SDR) towards hydrochar and bioethanol production. The experiments are designed by Box-Behnken design from response surface methodology where the operating conditions include sulfuric acid concentration (0, 0.01, and 0.02 M), amyloglucosidase concentration (36, 51, and 66 IU), and saccharification time (120, 180, and 240 min). Compared to conventional dry torrefaction, the hydrochar yield is between 13.24 and 14.73%, which is much lower than dry torrefaction biochar (yield >50%). The calorific value of the raw SDR is 17.15 MJ/kg, which is significantly enhanced to 22.36-23.37 MJ/kg after WT. When the sulfuric acid concentration increases from 0 to 0.02 M, the glucose concentration in the product increases from 5.59 g/L to 13.05 g/L. The prediction of analysis of variance suggests that the best combination to maximum glucose production is 0.02 M H2SO4, 66 IU enzyme concentration, and 120 min saccharification time, and the glucose concentration is 30.85 g/L. The maximum bioethanol concentration of 19.21 g/L is obtained, which is higher than those from wheat straw (18.1 g/L) and sweet sorghum residue (16.2 g/L). A large amount of SDR is generated in the kaoliang liquor production process, which may cause environmental problems if it is not appropriately treated. This study fulfills SDR valorization for hydrochar and bioenergy to lower environmental pollution and even achieve a circular economy.

15.
Ren Fail ; 43(1): 781-795, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33941037

RESUMEN

BACKGROUND: Tremendous scientific researches have been conducted in the field of diabetic kidney disease (DKD), while few bibliometric analyses have been performed. We aim to identify 100 top-cited published articles about DKD and analyze their main characteristics quantitatively. METHODS: Web of Science was searched with the term 'diabetic kidney disease' OR 'diabetic nephropathy' to identify the top 100 most cited articles. For articles meeting the predefined criteria, the following data were extracted and analyzed: citation ranking, publication year, publication journal, journal impact factor, country and institution, authors, study type, and keywords. RESULTS: The highest number of citations was 4753 times. The median average citations per year was 21.8 (IQR, 16.6-33.0). Most articles focused on the pathogenesis and treatment. These articles were published in 25 different journals and the Journal of the American Society of Nephrology published the greatest number (20%). Forty-three articles (43%) originated from the United States. The University of Groningen was the leading institute, contributing five top-cited articles. The most frequent first author was de Zeeuw (n = 4), followed by Parving (n = 3). There was no correlation between the average citations and the number of authors, the number of institutes, or the number of funds, respectively. Experimental animal study was the research type most frequently conducted (n = 30), followed by observational study (n = 24). Keyword analysis revealed transforming growth factor-ß, oxidative stress, proteinuria, and renin-angiotensin-aldosterone system interruption are classic research topics. Sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide 1 receptor agonists, and anti-inflammatory agents are the emerging trends of DKD. CONCLUSIONS: This bibliometric analysis helps in identifying the milestones, inadequacies, classic hotspots, and emerging trends of DKD. Pathogenesis and treatment are core themes in DKD research, while high-quality articles on the prediction and biomarker are insufficient. New analyzing metrics are needed to assess the actual impact of these top-cited articles on clinical practice.

16.
Artículo en Inglés | MEDLINE | ID: mdl-33941517

RESUMEN

Recently, mutations in the 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase gene (hmg1) have been identified to be associated with triazole resistance in Aspergillus fumigatus Here, we describe the first case of the G929C mutation in the hmg1 gene, leading to the W272C amino acid substitution, in a triazole-resistant isolate of A. fumigatus recovered from a chronic cavitary pulmonary aspergillosis patient who failed voriconazole therapy in China.

17.
Ann N Y Acad Sci ; 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33942910

RESUMEN

The association between sarcopenia and metabolic syndrome (MetS) has been well established. Nevertheless, the transition process between normal and low muscle mass (LMM) states and the effect of this transition on MetS has been less explored. Our study here examined whether the direction toward or away from LMM alters the risks of MetS. Initially, gene set enrichment analysis confirmed that MetS correlates with sarcopenia at the genetic level. Subsequently, 6476 eligible participants older than 60 years were enrolled between 2010 and 2016 at Tri-Service General Hospital, Taiwan for evaluation. We discovered an inverse association between the skeletal muscle mass percentage and the risk of MetS. Participants were categorized into four subgroups: state 1 (normal→normal), state 2 (LMM→normal), state 3 (normal→LMM), and state 4 (LMM→LMM). State 4 had increased hazard ratios (HRs) of MetS, while state 2 revealed decreased HRs of MetS, hypertension (HTN), and type II diabetes mellitus (T2DM). State 2 also showed decreased HRs for all five MetS components. Despite the fact that state 3 did not reach statistical significance, increased body fat percentage and glucose fluctuation were observed in this group. The transition direction toward LMM (states 3 and 4) showed deterioration in metabolic indices, leading to increased HRs for MetS, HTN, and T2DM. Conducting timely intervention during this transition process may effectively prevent adverse events accompanying LMM.

18.
Protein Expr Purif ; : 105893, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33933613

RESUMEN

MAP30 (Momordica antiviral protein 30kD) is a single-chain Ⅰ-type ribosome inactivating protein with a variety of biological activities, including anti-tumor ability. It was reported that MAP30 would serve as a novel and relatively safe agent for prophylaxis and treatment of liver cancer. To determine whether adding two tumor targeting peptides could improve the antitumour activities of MAP30, we genetically modified MAP30 with an RGD motif and a EGFRi motif, which is a ligand with high affinity for αvß3 integrins and with high affinity for EGFR. The recombinant protein ELRL-MAP30 (rELRL-MAP30) containing a GST-tag was expressed in E. coli. The rELRL-MAP30 was highly expressed in the soluble fraction after induction with 0.15 mM IPTG for 20 h at 16°C. The purified rELRL-MAP30 appeared as a band on SDS-PAGE. It was identified by western blotting. Cytotoxicity of recombinant protein to HepG2, MDA-MB-231, HUVEC and MCF-7 cells was detected by MTT analysis. Half maximal inhibitory concentration (IC50) values were 54.64 µg/mL, 70.13 µg/mL, 146 µg/mL, 466.4 µg/mL, respectively. Proliferation inhibition assays indicated that rELRL-MAP30 could inhibit the growth of Human liver cancer cell HepG2 effectively. We found that rELRL-MAP30 significantly induced apoptosis in liver cancer cells, as evidenced by nuclear staining of DAPI. In addition, rELRL-MAP30 induced apoptosis in human liver cancer HepG2 cells by up-regulation of Bax as well as down-regulation of Bcl-2. Migration of cell line were markedly inhibited by rELRL-MAP30 in a dose-dependent manner compared to the recombinant MAP30 (rMAP30). In summary, the fusion protein displaying extremely potent cytotoxicity might be highly effective for tumor therapy.

19.
Comput Methods Programs Biomed ; 205: 106102, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33933712

RESUMEN

BACKGROUND AND OBJECTIVE: Malignant ventricular arrhythmias (MAs) occur unpredictably and lead to emergencies. A new approach that uses a timely tracking device e.g., photoplethysmogram (PPG) solely to predict MAs would be irreplaceably valuable and it is natural to expect the approach can predict the occurrence as early as possible. METHOD: We assumed that with an appropriate metric based on signal complexity, the heartbeat interval time series (HbIs) can be used to manifest the intrinsic characteristics of the period immediately precedes the MAs (preMAs). The approach first characterizes the patterns of preMAs by a new complexity metric (the refined composite multi-scale entropy). The MAs detector is then constructed by checking the discriminability of the MAs against the sinus rhythm and other prevalent arrhythmias (atrial fibrillation and premature ventricular contraction) of three machine-learning models (SVM, Random Forest, and XGboost). RESULTS: Two specifications are of interest: the length of the HbIs needed to delineate the preMAs patterns sufficiently (lspec) and how long before the occurrence of MAs will the HbIs manifest specific patterns that are distinct enough to predict the impending MAs (tspec). Our experimental results confirmed the best performance came from a Random-Forest model with an average precision of 99.99% and recall of 88.98% using a HbIs of 800 heartbeats (the lspec), 108 seconds (the tspec) before the occurrence of MAs. CONCLUSION: By experimental validation of the unique pattern of the preMAs in HbIs and using it in the machine learning model, we showed the high possibility of MAs prediction in a broader circumstance, which may cover daily healthcare using the alternative sensor in HbIs monitoring. Therefore, this research is theoretically and practically significant in cardiac arrest prevention.

20.
Adv Mater ; : e2008523, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33938044

RESUMEN

Current synthetic elastomers suffer from the well-known trade-off between toughness and stiffness. By a combination of multiscale experiments and atomistic simulations, a transparent unfilled elastomer with simultaneously enhanced toughness and stiffness is demonstrated. The designed elastomer comprises homogeneous networks with ultrastrong, reversible, and sacrificial octuple hydrogen bonding (HB), which evenly distribute the stress to each polymer chain during loading, thus enhancing stretchability and delaying fracture. Strong HBs and corresponding nanodomains enhance the stiffness by restricting the network mobility, and at the same time improve the toughness by dissipating energy during the transformation between different configurations. In addition, the stiffness mismatch between the hard HB domain and the soft poly(dimethylsiloxane)-rich phase promotes crack deflection and branching, which can further dissipate energy and alleviate local stress. These cooperative mechanisms endow the elastomer with both high fracture toughness (17016 J m-2 ) and high Young's modulus (14.7 MPa), circumventing the trade-off between toughness and stiffness. This work is expected to impact many fields of engineering requiring elastomers with unprecedented mechanical performance.

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