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1.
Purinergic Signal ; 2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35000074

RESUMO

Pain is a common clinical symptom that seriously affects the quality of life in a variety of patient populations. In recent years, research on the role of adenosine signaling in pain modulation has made great progress. Adenosine is a purine nucleoside and a neuromodulator, and regulates multiple physiological and pathophysiological functions through the activation of four G protein-coupled receptors, which are classified as A1, A2A, A2B, and A3 adenosine receptors (ARs). Adenosine and its receptors that are widespread in the central nervous system (CNS) play an important role in the processing of nociceptive sensory signals in different pain models. A1Rs have the highest affinity to adenosine, and the role in analgesia has been well investigated. The roles of A2ARs and A2BRs in the modulation of pain are controversial because they have both analgesic and pronociceptive effects. The analgesic effects of A3Rs are primarily manifested in neuropathic pain. In this article, we have reviewed the recent studies on ARs in the modulation of neuropathic pain, inflammatory pain, postoperative pain, and visceral pain in the CNS. Furthermore, we have outlined the pathways through which ARs contribute to pain regulation, thereby shedding light on how this mechanism can be targeted to provide effective pain relief.

2.
Mater Horiz ; 8(9): 2553-2561, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34870301

RESUMO

Biological tissues can grow stronger after damage and self-healing. However, artificial self-healing materials usually show decreased mechanical properties after repairing. Here, we develop a self-healing strengthening elastomer (SSE) by engineering kinetic stability in an ionomer. Such kinetic stability is enabled by designing large steric hindrance on the cationic groups, which prevents the structural change driven by thermodynamic instability under room temperature. However, once heat or external force is applied to disrupt the kinetic stability, the inherent thermodynamic instability induces the SSEs to form bigger and denser aggregates, thereby the material becomes stronger during the healing process. Consequently, the self-healing efficiency of fractured SSEs is as high as 143%. Unlike conventional ionomers whose mechanical properties change with time uncontrollably due to the thermodynamic instability, the SSEs show tunable self-healing strengthening behavior, thanks to the kinetic stability. This work provides a novel and universal strategy to fabricate biomimetic self-healing strengthening materials.

3.
Front Cell Dev Biol ; 9: 758776, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34912802

RESUMO

Colon cancer is a complex, heterogeneous disease. The Colorectal Cancer Subtyping Consortium reported a novel classification system for colon cancer in 2015 to better understand its heterogeneity. This molecular classification system divided colon cancer into four distinct consensus molecular subtypes (CMS 1, 2, 3, and 4). However, the characteristics of different colon cancer molecular subtypes have not been fully elucidated. This study comprehensively analyzed the molecular characteristics of varying colon cancer subtypes using multiple databases and algorithms, including The Cancer Genome Atlas (TCGA) database, DriverDBv3 database, CIBERSORT, and MCP-counter algorithms. We analyzed the alterations in the subtype-specific genes of different colon cancer subtypes, such as the RNA levels and DNA alterations, and showed that specific subtype-specific genes significantly affected prognosis. We also explored the changes in colon cancer driver genes and representative genes of 10 signaling pathways in different subtypes. We identified genes that were altered in specific subtypes. We further detected the infiltration of 22 immune cell types in four colon cancer subtypes and the infiltration level of primary immune cells among these subtypes. Additionally, we explored changes in immune checkpoint genes (ICGs) and immunotherapy responses among different colon cancer subtypes. This study may provide clues for the molecular mechanism of tumorigenesis and progression in colon cancer. It also offers potential biomarkers and targets for the clinical diagnosis and treatment of different colon cancer subtypes.

4.
Front Endocrinol (Lausanne) ; 12: 755575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777252

RESUMO

Objectives: To investigate the spatial distribution of 10-year incidence of diagnosed type 2 diabetes mellitus (T2DM) and its association with obesity and physical inactivity at a reginal level breakdown. Methods: Demographic, behavioral, medical and pharmaceutical and diagnosed T2DM incidence data were collected from a cohort of 232,064 participants who were free of diabetes at enrolment in the 45 and Up Study, conducted in the state of New South Wales (NSW), Australia. We examined the geographical trend and correlation between obesity prevalence, physical inactivity rate and age-and-gender-adjusted cumulative incidence of T2DM, aggregated based on geographical regions. Result: The T2DM incidence, prevalence of obesity and physical inactivity rate at baseline were 6.32%, 20.24%, and 18.7%, respectively. The spatial variation of T2DM incidence was significant (Moran's I=0.52; p<0.01), with the lowest incidence of 2.76% in Richmond Valley-Coastal and the highest of 12.27% in Mount Druitt. T2DM incidence was significantly correlated with the prevalence of obesity (Spearman r=0.62, p<0.001), percentage of participants having five sessions of physical activities or less per week (r=0.79, p<0.001) and percentage of participants walked to work (r=-0.44, p<0.001). The geographical variations in obesity prevalence and physical inactivity rate resembled the geographical variation in the incidence of T2DM. Conclusion: The spatial distribution of T2DM incidence is significantly associated with the geographical prevalence of obesity and physical inactivity rate. Regional campaigns advocating the importance of physical activities in response to the alarming T2DM epidemic should be promoted.

5.
Gels ; 7(4)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34698196

RESUMO

Many high-strength hydrogels have been developed in recent years; however, few of them are both tough and resilient, and their intrinsic paradoxical nature makes designing a gel with both high toughness and high resilience a great challenge. To address this problem, we introduced both N,N,N,N-pentamethyldiethylenetriamine (PA) and N,N-methylenebisacrylamide (MBA) into polyacrylamide hydrogel networks to construct an entangled network that contains chemically cross-linked chains and branched chains simultaneously. The entanglements of branched chains can act as a physical cross-linking point to uniformly disperse stress on molecular chains, and chemical cross-linking ensures the stability of the hydrogel network. The increase in the number and length of branched chains is able to achieve an enhancement in strength while the slip of the entangled polymer chains can effectively achieve energy dissipation and can improve the toughness of the gel. Moreover, the resultant hydrogels exhibit an excellent resilience (>98%). Therefore, high toughness and resilience are achieved simultaneously. In addition, we also investigated the initiation mechanism of PA. This strategy creates a new way for the preparation of next-generation high toughness and high resilience hydrogel-based materials, which have promising applications in wearable, flexible strain/pressure sensors.

6.
ACS Appl Mater Interfaces ; 13(36): 43404-43413, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34478274

RESUMO

Realizing simultaneous antiwater and anti-oil-fouling adhesion is extremely challenging owing to the solvated overlayer on the surface of substrates. Herein, we develop a supertough polyacrylate-based tape bearing SiO2 as a reinforcing filler and a solvent to liquefy the surface. The SiO2 reinforcement enhances the cohesion strength, while the liquefied surface not only expels the solvated overlayer but also improves the interfacial wettability and interaction. This material design imparts the double-sided tape with admirable antiwater and anti-oil-fouling adhesion performance, which far exceeds that of commercial tapes, as well as high transparency and long-term stability. In addition, we carry out an in-depth study on the adhesive mechanism for the tape and clarify the role of the solvent and the interaction between SiO2 and a polymer matrix. This work provides a novel strategy for designing antiwater and anti-oil-fouling adhesives with wide applications in various fields such as leakage repair, antiseep, underwater adhesion, building materials, and biological adhesives.

7.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443376

RESUMO

In order to reduce the environmental pollution caused by waste rubber and to realize the recycling of resources, we proposed a facile method for the hydrophilic modification of waste rubber powder (HRP) and used it to reinforce a composite hydrogel. In the presence of toluene, dibenzoyl peroxide (BPO) diffused into the waste rubber powder. After the solvent was removed, BPO was adsorbed in the rubber powder, which was used to initiate the grafting polymerization of the acrylamide monomer on the rubber-water interface. As a result, the polyacrylamide (PAM) molecular chains were grafted onto the surface of the rubber powder to realize hydrophilic modification. The success of the grafting modification was confirmed by FTIR, contact angle testing, and thermogravimetric analysis. The hydrophilic modified waste rubber powder was used to reinforce the PAM hydrogel. Mechanical tests showed that the tensile strength and elongation at the break of the composite hydrogel reached 0.46 MPa and 1809%, respectively, which was much higher than those of pure PAM hydrogel. Such a phenomenon indicates that the waste rubber particles had a strengthening effect.

8.
Front Bioeng Biotechnol ; 9: 618029, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150723

RESUMO

Daptomycin, which is produced by Streptomyces roseosporus, has been characterized as a novel cyclic lipopeptide antibiotic that is effective against Gram-positive bacteria. The biosynthesis of daptomycin is regulated by various factors. In the present study, we demonstrated that the cyclic AMP receptor protein (Crp) plays an important role in producing daptomycin in the S. roseosporus industrial strain. We found that daptomycin production from the crp deletion strain decreased drastically, whereas production from the crp overexpression strain increased by 22.1%. Transcriptome and qPCR analyses showed that some genes related to the daptomycin biosynthetic gene cluster (dpt) and the pleiotropic regulator (adpA) were significantly upregulated. RNA-seq also shows Crp to be a multifunctional regulator that modulates primary metabolism and enhances precursor flux to secondary metabolite biosynthesis. These results provide guidance for the development and improvement of potential natural products.

9.
J BUON ; 26(2): 643, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34077027

RESUMO

The Editors of JBUON issue an Expression of Concern to 'Tormentic acid induces anticancer effects in cisplatin-resistant human cervical cancer cells mediated via cell cycle arrest, ROS production, and targeting mTOR/PI3K/AKT signalling pathway', by Jinrong Wu, Ning Wang, Gang Jin, Lili Xue, JBUON 2020;25(1):74-79; PMID: 32277616. Following the publication of the above article, readers drew to our attention that part of the data was possibly unreliable. We sent emails to the authors with a request to provide the raw data to prove the originality, but received no reply. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.

10.
Cell Res ; 31(6): 631-648, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782530

RESUMO

RNAi therapy has undergone two stages of development, direct injection of synthetic siRNAs and delivery with artificial vehicles or conjugated ligands; both have not solved the problem of efficient in vivo siRNA delivery. Here, we present a proof-of-principle strategy that reprogrammes host liver with genetic circuits to direct the synthesis and self-assembly of siRNAs into secretory exosomes and facilitate the in vivo delivery of siRNAs through circulating exosomes. By combination of different genetic circuit modules, in vivo assembled siRNAs are systematically distributed to multiple tissues or targeted to specific tissues (e.g., brain), inducing potent target gene silencing in these tissues. The therapeutic value of our strategy is demonstrated by programmed silencing of critical targets associated with various diseases, including EGFR/KRAS in lung cancer, EGFR/TNC in glioblastoma and PTP1B in obesity. Overall, our strategy represents a next generation RNAi therapeutics, which makes RNAi therapy feasible.

11.
J Gastrointest Oncol ; 12(1): 69-78, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33708425

RESUMO

Background: Polyps may develop into colorectal cancer (CRC) after 10-20 years. The occurrence of polyps and tumors caused by somatic gene mutations is considered a main pathogenesis of CRC. Among all general patients with polyps or CRC, some had adenoma of varying degrees that were consistent with familial colorectal adenomas. A patient with CRC (the propositus) and his brothers and sister, all of whom had varying degrees of colorectal polyps showed different adenomas with different members in a family. Methods: In the present study, a total of 9 family members were investigated, and a family tree was drawn. Genomic DNA was extracted from peripheral venous blood samples from family members, and whole-exome sequencing (WES) and Sanger sequencing were performed on the DNA samples. The result of WES was compared with compared directly to the reference genome (hg19) with Burrows-Wheeler Aligner, which is as control group from. Results: We identified a base substitution in the miR-4477b gene (c.68415368T>G, chromosome 9 q13), predicted the target gene of miR-4477b through the biologic website, and analyzed the Gene Ontology (GO) and signal pathway of the target gene. The GO functional annotation analysis of the target gene of mir4477b revealed that these genes are involved mainly in the G1/S transition of the mitotic cell cycle, activation of mitogen-activated protein kinase activity, protein phosphorylation, and membrane, centrosome, cytoplasm, zinc ion-binding, protein-binding, and ligase activity. Kyoto Encyclopedia of Gene and Genomes pathway analysis revealed that miR-4477b regulates target genes mainly involved in the phosphoinositide 3-kinase/Akt signaling pathway, regulation of the actin cytoskeleton, proteoglycans in cancer, pathways in cancer, and renal cell carcinoma. Conclusions: The mutation of the has-mir-4477b gene likely leads to the occurrence of adenoma and CRC. In-depth studies of patients from the same family with different stages of adenoma can avoid errors caused by gene diversity, incomplete clinical data, and uncertain disease development. The has-mir-4477b gene may represent a key gene mutation in colorectal carcinogenesis and a multiyear cancer risk for patients that requires further attention.

12.
ACS Appl Mater Interfaces ; 13(1): 1535-1544, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33379861

RESUMO

Despite recent advances in bioinspired underwater adhesives, achieving tough, fast, and stable adhesion in aqueous environments is still challenging. Here, an underwater super-tape with semi-interpenetrating polymer networks (SIPNs) and a water-repelling liquid surface is synthesized. In the SIPN, the linear chains easily diffuse to adapt to the adherends, and the cross-linked chains provide the super-tape with high dimensional stability. Meanwhile, both the linear and cross-linked chains bear many catechol groups, which can not only vigorously interact with the adherends but also form numerous hydrogen bonds serving as sacrificial bonds in the SIPN. Thus, the super-tape shows both high interfacial adhesion and cohesive energy. Moreover, the super-tape is covered with a water-repelling liquid surface by spraying it with traces of a hydrophobic solvent. It is demonstrated that the hydrophobic solvent absorbed on the surface of the super-tape can remove water between the tape and adherends, enabling their intimate contact to form a strong interaction. As such, the super-tape shows excellent instant adhesion property under water, and the adhesive strength and toughness increase with time and reach their maximum values at around 5 h. The maximum debonding energy of the super-tape reaches 3933 J m-2, which is much higher than those of existing double-sided tapes.

13.
J Infect ; 82(1): 48-59, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33189772

RESUMO

OBJECTIVES: We aimed to develop machine learning models and evaluate their performance in predicting HIV and sexually transmitted infections (STIs) diagnosis based on a cohort of Australian men who have sex with men (MSM). METHODS: We collected clinical records of 21,273 Australian MSM during 2011-2017. We compared accuracies for predicting HIV and STIs (syphilis, gonorrhoea, chlamydia) diagnosis using four machine learning approaches against a multivariable logistic regression (MLR) model. RESULTS: Machine learning approaches consistently outperformed MLR. Gradient boosting machine (GBM) achieved the highest area under the receiver operator characteristic curve for HIV (76.3%) and STIs (syphilis, 85.8%; gonorrhoea, 75.5%; chlamydia, 68.0%), followed by extreme gradient boosting (71.1%, 82.2%, 70.3%, 66.4%), random forest (72.0%, 81.9%, 67.2%, 64.3%), deep learning (75.8%, 81.0%, 67.5%, 65.4%) and MLR (69.8%, 80.1%, 67.2%, 63.2%). GBM models demonstrated the ten greatest predictors collectively explained 62.7-73.6% of variations in predicting HIV/STIs. STIs symptoms, past syphilis infection, age, time living in Australia, frequency of condom use with casual male sexual partners during receptive anal sex and the number of casual male sexual partners in the past 12 months were most commonly identified predictors. CONCLUSIONS: Machine learning approaches are advantageous over multivariable logistic regression models in predicting HIV/STIs diagnosis.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Doenças Sexualmente Transmissíveis , Sífilis , Austrália/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Lactente , Aprendizado de Máquina , Masculino , Prevalência , Comportamento Sexual , Parceiros Sexuais , Doenças Sexualmente Transmissíveis/diagnóstico , Doenças Sexualmente Transmissíveis/epidemiologia , Sífilis/diagnóstico , Sífilis/epidemiologia
14.
Front Chem ; 8: 585569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195082

RESUMO

Developing degradable and self-healable elastomers composed of reusable resources is of great value but is rarely reported because of the undegradable molecular chains. Herein, we report a class of degradable and self-healable vitrimers based on non-isocyanate polyurethane elastomer. Such vitrimers are fabricated by copolymerizing bis(6-membered cyclic carbonate) and amino-terminated liquid nitrile rubber. The networks topologies can rearrange by transcarbonation exchange reactions between hydroxyl and carbonate groups at elevated temperatures; as such, vitrimers after reprocessing can recover 82.9-95.6% of initial tensile strength and 59-131% of initial storage modulus. Interestingly, the networks can be hydrolyzed and decarbonated in the strong acid solution to recover 75% of the pure di(trimethylolpropane) monomer. Additionally, the elastomer exhibits excellent self-healing efficiency (~88%) and fracture strain (~1,200%) by tuning the monomer feeding ratio. Therefore, this work provides a novel strategy to fabricate the sustainable elastomers with minimum environmental impact.

15.
ACS Appl Mater Interfaces ; 12(47): 53239-53246, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33197169

RESUMO

Due to the dynamic nature of networks and high mobility of molecular chains, self-healing elastomers are usually confronted with the trade-off between self-healing efficiency and mechanical properties. Herein, a self-healing ionomer with both high mechanical performance and high self-healing efficiency has been successfully developed by grafting bromobutyl rubber (BIIR) with pyridine-based derivatives. Interestingly, the substituents on the pyridine ring can be used to regulate the interaction forces of ionic clusters and molecular dynamics. The electron-donating effect of the substituents facilitates stable π-π stacking between pyridyl ions, inducing the formation of regular and large ion aggregates, thereby improving the mechanical strength of the ionomer. Meanwhile, the plasticizing effect of the substituents reduces the activation energy and relaxation temperature of the ionic aggregates, thus endowing the ionomer with a high self-healing efficiency. As a result, the ionomer shows tensile strength as high as 8.1 ± 0.3 MPa under room temperature and self-healing efficiency of 100 ± 3% at 60 °C. Therefore, this strategy can be easily extended to other halogen-containing polymers, leading to a novel class of self-healing ionomers that hold great promise in diverse applications.

16.
Prev Med ; 141: 106260, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33017600

RESUMO

Although socioeconomic, behavioural, psychological, and biological factors have been individually linked to multimorbidity, data on the importance of these factors are limited. Our study aimed to determine the leading predictors for multimorbidity of chronic conditions in middle-aged Australian adults using machine learning methods. We included 53,867 participants aged 45-64 years from the 45 and Up Study who were free of eleven predefined chronic conditions at baseline (2006-2009) in the analysis. Incident multimorbidity was defined by the co-existence of ≥2, ≥3, or ≥ 4 conditions during follow-up until December 31, 2016. The five leading predictors for multimorbidity in men were age (7.2-20.5% of total variance), body mass index (6.5-15.4%), smoking (4.0-8.3%), chicken intake (3.6-7.5%), and red meat intake (4.6-6.3%) across the three definitions. Leading predictors varied across the three definitions in women, but the four common ones were body mass index (6.3-20.1%), age (6.2-16.4%), chicken intake (4.1-8.3%), and red meat intake (4.2-4.7%). The ten leading modifiable health factors accounted for 39.4-46.1% of total variance across the three definitions. Men with 6-10 health factors had 46-54% lower risks for multimorbidity compared with those reporting ≤2. The corresponding percentage for women was 45-52%. Non-behavioural factors including psychological distress, low education and income and high relative economic disadvantage were among the leading risk factors for multimorbidity. In conclusion, modifications on behavioural factors including diets, physical activity, smoking, alcohol consumption may reduce the risk of multimorbidity in middle-aged adults, whereas individuals with low socioeconomic status or psychological distress are at the highest priority for intervention.


Assuntos
Multimorbidade , Adulto , Austrália/epidemiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
17.
FASEB J ; 34(10): 13762-13775, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32808351

RESUMO

Cerebral ischemia causes damage to the structure and function of the blood-brain barrier (BBB) and alleviating BBB destruction will be of great significance for the treatment and prognosis of ischemic stroke. Recently, microRNAs have been shown to play a critical role in BBB integrity. However, the potential mechanism by which microRNA-182 (miR-182) affects the BBB in ischemic stroke remains unclear. We demonstrated for the first time that cerebral ischemia leads to a significant progressive increase in miR-182 after pMCAO, and bEnd.3 cells are the primary target cells of miR-182. In miR-182 KD transgenic mice, infarct volume, and BBB permeability were attenuated, and tight junction (TJ) proteins increased. Inhibition of miR-182 with an antagomir reduced OGD-induced apoptosis of bEnd.3 cells and the loss of ZO-1 and Occludin. To further explore the mechanism by which miR-182 regulates BBB integrity, we detected the apoptotic proteins Bcl-2/Bax and demonstrated that mTOR and FOXO1 were the targets of miR-182. Inhibition of mTOR/FOXO1 by rapamycin/AS1842856 decreased the ratio of Bcl-2/Bax and exacerbated TJ protein loss. Taken together, inhibition of miR-182 protects BBB integrity by reducing endothelial cell apoptosis through the mTOR/FOXO1 pathway. Thus, miR-182 may be a potential target for the treatment of BBB disruption during cerebral ischemia.


Assuntos
Barreira Hematoencefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Animais , Apoptose , Linhagem Celular , Células Cultivadas , Regulação para Baixo , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Infarto da Artéria Cerebral Média/genética , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo
18.
JMIR Med Inform ; 8(7): e16850, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32720912

RESUMO

BACKGROUND: Previous conventional models for the prediction of diabetes could be updated by incorporating the increasing amount of health data available and new risk prediction methodology. OBJECTIVE: We aimed to develop a substantially improved diabetes risk prediction model using sophisticated machine-learning algorithms based on a large retrospective population cohort of over 230,000 people who were enrolled in the study during 2006-2017. METHODS: We collected demographic, medical, behavioral, and incidence data for type 2 diabetes mellitus (T2DM) in over 236,684 diabetes-free participants recruited from the 45 and Up Study. We predicted and compared the risk of diabetes onset in these participants at 3, 5, 7, and 10 years based on three machine-learning approaches and the conventional regression model. RESULTS: Overall, 6.05% (14,313/236,684) of the participants developed T2DM during an average 8.8-year follow-up period. The 10-year diabetes incidence in men was 8.30% (8.08%-8.49%), which was significantly higher (odds ratio 1.37, 95% CI 1.32-1.41) than that in women at 6.20% (6.00%-6.40%). The incidence of T2DM was doubled in individuals with obesity (men: 17.78% [17.05%-18.43%]; women: 14.59% [13.99%-15.17%]) compared with that of nonobese individuals. The gradient boosting machine model showed the best performance among the four models (area under the curve of 79% in 3-year prediction and 75% in 10-year prediction). All machine-learning models predicted BMI as the most significant factor contributing to diabetes onset, which explained 12%-50% of the variance in the prediction of diabetes. The model predicted that if BMI in obese and overweight participants could be hypothetically reduced to a healthy range, the 10-year probability of diabetes onset would be significantly reduced from 8.3% to 2.8% (P<.001). CONCLUSIONS: A one-time self-reported survey can accurately predict the risk of diabetes using a machine-learning approach. Achieving a healthy BMI can significantly reduce the risk of developing T2DM.

19.
ACS Appl Mater Interfaces ; 12(23): 26509-26514, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32408733

RESUMO

The joint membrane of the American lobster shows an excellent combination of high strength, toughness, and defect tolerance due to the periodic helicoidal stacking of the fiber layers that are connected by a weak continuous matrix. Inspired by the joint membrane of American lobsters, we simply use nonwoven fabrics and silicon rubber to fabricate a multilayer soft composite with the helicoidal stacking and controllable matrix. The influences of stacking structure, matrix strength, fabrics strength, and notch size on the fracture behavior of the soft composite during the tensile process are systematically analyzed by both experimental tests and finite element analysis (FEA). We find that similar to the joint membrane, the soft composite demonstrates a gradual failure process and a linear relationship between tensile strength/toughness and notch size. Such phenomena demonstrate the strong defect-tolerant ability, thereby imparting the soft composite with both high strength and toughness. The defect-tolerant ability is closely related to the helicoidal stacking and weak matrix between the fabrics layers, which induce crack deflection and inhibit the propagation of cracks across the sample.


Assuntos
Materiais Biomiméticos/química , Elastômeros de Silicone/química , Têxteis , Animais , Análise de Elementos Finitos , Teste de Materiais , Nephropidae , Nylons/química , Polipropilenos/química , Estresse Mecânico , Resistência à Tração
20.
Proc Natl Acad Sci U S A ; 117(21): 11299-11305, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32381742

RESUMO

Glassy polymers are extremely difficult to self-heal below their glass transition temperature (T g) due to the frozen molecules. Here, we fabricate a series of randomly hyperbranched polymers (RHP) with high density of multiple hydrogen bonds, which show T g up to 49 °C and storage modulus up to 2.7 GPa. We reveal that the hyperbranched structure not only allows the external branch units and terminals of the molecules to have a high degree of mobility in the glassy state, but also leads to the coexistence of "free" and associated complementary moieties of hydrogen bonds. The free complementary moieties can exchange with the associated hydrogen bonds, enabling network reconfiguration in the glassy polymer. As a result, the RHP shows amazing instantaneous self-healing with recovered tensile strength up to 5.5 MPa within 1 min, and the self-healing efficiency increases with contacting time at room temperature without the intervention of external stimuli.

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