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1.
Nano Lett ; 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851648

RESUMO

Because of the extraordinary properties including high atomic numbers and large µτ products, metal halide perovskites have been widely employed and used for radiation detecting. Cs4PbI6 material has a high X-ray attenuation coefficient and excellent electrical properties that have a good potential in X-ray detection applications. Here, we have designed a flexible polymer-encapsulated Au/Cs4PbI6/Au X-ray detector with outstanding sensitivity of 256.20 µC Gy-1 cm-2 irradiated by 30 keV X-ray at 10 V bias, long-time stability, and durable flexibility without obvious degradation after bending for 600 cycles. These features demonstrate that this polymer-encapsulated durable flexible and sensitive X-ray detector could open a new possibility for next-generation radiation applications in dosimeter, imaging technologies.

2.
ACS Appl Mater Interfaces ; 13(45): 54348-54353, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34735128

RESUMO

A surface modified-CsPbBr3/polybutylmethacrylate (PBMA) nanocomposite is reported to be a scintillator that enables us to provide a high contrast X-ray image using a common charge-coupled device (CCD) camera. Bis(2-(methacryloyloxy)ethyl) phosphate (BMEP) was employed to alter the ratio of the original ligands on the CsPbBr3 nanocrystal (NC) surface for optimizing the optical performance of the CsPbBr3/PBMA nanocomposites. The nanocomposites with a concentration of 0.02 wt % NCs exhibit more than 70% transmittance in the visible region and show a green emission at 515 nm, the fast decay time is 13 ns, while the photoluminescence quantum yield value is 99.2%. Under X-ray excitation, the emission peak wavelength is centered at 524 nm and shows a narrow full width at half-maximum of 26.6 nm; the result nicely matches with the peak quantum efficiency of most commercial CCD/complementary metal oxide semiconductor cameras. The high contrast X-ray image is recorded at a low dose rate of 4.6 µGyair/s, which enables read out with software. Our results demonstrate that these CsPbBr3/PBMA nanocomposites have promising application prospects for ionizing radiation detection, especially for X-ray imaging.

3.
Front Endocrinol (Lausanne) ; 12: 736906, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603212

RESUMO

Female moths use sex pheromones to attract males, and corresponding regulatory mechanism underlying sex pheromone biosynthesis is species-dependent. However, the detailed mechanism involved in sex pheromone biosynthesis in Ostrinia furnacalis has not yet been fully addressed. In the present study, transcriptome sequencing of O. furnacalis pheromone glands screened a serials of candidate genes involved in sex pheromone biosynthesis. Our analysis showed that sex pheromone release in O. furnacalis females arrives its peak at the 2nd scotophase, consistent with its mating behavior. Pheromone biosynthesis-activating neuropeptide (PBAN) was confirmed to regulate sex pheromone biosynthesis, and Ca2+ is the secondary messenger of PBAN signaling in O. furnacalis. The functional analysis of candidate genes demonstrated that the decreased mRNA levels or activities of calcineurin (CaN) and acetyl-CoA carboxylase (ACC) led to significant decrease in sex pheromone production and female capability to attract males, as demonstrated by RNAi-mediated knockdown and pharmacological inhibitor assay. Most importantly, the activities of CaN and ACC depend on the activation of PBAN/PBANR/Ca2+. Furthermore, fatty-acyl reductase 14 was involved in PBAN-mediated sex pheromone biosynthesis. Altogether, our results demonstrated that PBAN regulates sex pheromone biosynthesis through PBANR/Ca2+/CaN/ACC pathway to promote sex pheromone biosynthesis in O. furnacalis and provided a reference for non-model organism to study neuropeptide signal transduction.

4.
Opt Express ; 29(16): 24792-24803, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614827

RESUMO

Scintillators play an important role in the field of nuclear radiation detection. However, the light output of the scintillators is often limited by total internal reflection due to the high refractive indices of the scintillators. Furthermore, the light emission from scintillators typically has an approximately Lambertian profile, which is detrimental to the collection of the light. In this paper, we demonstrate a promising method to achieve enhancement of the light output from scintillators through use of mixed-scale microstructures that are composed of a photonic crystal slab and a microlens array. Simulations and experimental results both show significant improvements in the scintillator light output. The X-ray imaging characteristics of scintillators are improved by the application of the mixed-scale microstructures. The results presented here suggest that the application of the proposed mixed-scale microstructures to scintillators will be beneficial in the nuclear radiation detection field.

5.
Medicine (Baltimore) ; 100(37): e26952, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34664826

RESUMO

ABSTRACT: It is necessary to elucidate the potential risk factors of pulmonary infection to provide references for the management of breast cancer.Our study was a retrospective design, patients who underwent modified radical mastectomy for breast cancer in our department of breast surgery from January 2019 to November 2020 were included. The personal and clinical data of included patients with and without pulmonary infection were compared.A total of 234 patients with radical mastectomy were included, the incidence of pulmonary infection was 15.38% with 95%confidence interval (CI) 11.42% to 18.98%. There were significant differences in the age, body mass index, diabetes, duration of surgery, combined radiotherapy and chemotherapy, and duration of drainage between patients with and without pulmonary infections (all P < .05). Logistic regression analysis indicated that age ≥55 years (odds ratio [OR] 2.128, 95%CI 1.105-3.426), body mass index ≥ 24 kg/m2(OR 2.344, 95%CI 1.031-3.299), diabetes (OR 2.835, 95%CI 1.132-4.552), duration of surgery ≥120 minutes (OR 1.394, 95%CI 1.012-1.044), combined radiotherapy and chemotherapy (OR 3.122, 95%CI 1.124-5.273), duration of drainage ≥5 days (OR 1.851, 95%CI 1.112-2.045) might be the independent risk factors of pulmonary infection in patients after radical mastectomy(all P < .05). Pseudomonas aeruginosa and Klebsiella pneumoniae are the most commonly seen bacteria.The incidence of postoperative pulmonary infections in breast cancer patients is high, and there are many associated risk factors. The perioperative management of patients should be strengthened targeted on those risk factors in clinical practice.


Assuntos
Neoplasias da Mama/complicações , Complicações Pós-Operatórias/prevenção & controle , Infecções Respiratórias/prevenção & controle , Adulto , Índice de Massa Corporal , Neoplasias da Mama/cirurgia , Feminino , Humanos , Incidência , Mastectomia/efeitos adversos , Mastectomia/métodos , Mastectomia/estatística & dados numéricos , Pessoa de Meia-Idade , Razão de Chances , Complicações Pós-Operatórias/etiologia , Infecções Respiratórias/etiologia , Estudos Retrospectivos , Fatores de Risco
6.
J Biomed Nanotechnol ; 17(10): 2085-2098, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34706808

RESUMO

With the progress made in the widespread application of interventional radiology procedures, there has been an increasing number of patients who suffer from cardiovascular diseases and go through imaging and interventional treatment with iodine contrast medium (ICM) year by year. In turn, there has been an increasing amount of concern over acute kidney injury (AKI) brought about by ICM. As evidenced by numerous studies, the initiation of inflammatory response plays a critical role in the development of ICM-induced AKI. Correspondingly, the strategy of targeting renal inflammatory response and cytokine release could provide an effective solution to mitigating the ICM-induced AKI. Moreover, Ginsenoside Rb1 (GRb1) constitutes one of the major active components of ginseng and features a wide range of vital biological functions. Judging from the research findings, GRb1 could impose antioxidant and anti-inflammatory effects on cardiovascular diseases, in addition to lung, liver and kidney diseases. However, reports on whether GRb1 could impose a protective effect against contrast-induced nephropathy (CIN) are absent. In this study, we have examined the therapeutic effects imposed by GRb1 as well as the potential molecular mechanism by establishing an in vivo and in vitro model of CIN. In addition, we have set up a mouse model of CIN through sequential intravenous injection of indomethacin, N(ω)-nitro-Larginine methyl ester (L-NAME), and iopromide. To further enhance the bioavailability of GRb1, we have encapsulated GRb1 with polyethylene glycol (PEG)/poly lactic-co-glycolic acid (PLGA) nanocarriers to generate GRb1 nanoparticles (NPs) conducting the in vivo experiments. During the in vitro experiments, we have adopted GRb1 to treat NRK-52E cells or cells transfected with the high mobility group box 1 gene (HMGB1) overexpression plasmid. As shown by the in vivo experimental results, GRb1 NPs could evidently improve the renal dysfunction in CIN, diminish the extent of apoptosis of tubular epithelial cells, and reduce the expression of high mobility group box 1 (HMGB1) and cytokines (tumor necrosis factor (TNF-α), interleukin (IL) 6 and IL-1ß). In addition, GRb1 NPs are found to be capable of preventing the activation of Toll-like receptor 4 (TLR4)/NF-κB signaling pathway triggered by contrast medium. The in vitro experimental results have exactly confirmed the findings of the in vivo experiments. In the meantime, through the observation of the in vitro assays, overexpression of HMGB1 can partially counteract the beneficial effects imposed by GRb1. Judging from our research data, GRb1 could impose a protective effect against CIN by inhibiting inflammatory response via HMGB1/TLR4/NF-κB pathway, whereas HMGB1 constitutes a critical molecular target of GRb1.


Assuntos
Nefropatias , Nanopartículas , Animais , Ginsenosídeos , Humanos , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Nanopartículas/toxicidade , Proteínas de Ligação a Retinoblastoma , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Ubiquitina-Proteína Ligases
7.
Small ; : e2102392, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34636135

RESUMO

The unique structural advantage and physicochemical properties render some 2D materials emerging platforms for intracellular bioimaging, biosensing, or disease theranostics. Despite recent advances in this field, one major challenge lies in bypassing the endocytic uptake barrier to allow internalization of very large 2D materials that have longer retention time in cells, and hence greater potency as intracellular functional platforms than small, endocytosable counterparts. Here, an engineered cucurbit[6]uril carrying at its periphery multiple spiropyran pendants that readily translocates into cytosol, and then polymerizes laterally and non-covalently in a controlled manner, enabling direct generation of 2D materials inside living cells, is reported. The resultant 2D materials are single-monomer-thick and can in situ grow up to 0.8-1.2 µm in lateral size, experimentally proved too large to be endocytosed from outside the cells even after surface engineered with biorecognition entities. A Förster resonance energy transfer assay is further devised for real-time visualization of the polymerization dynamics in vivo, clearly demonstrating the rationale in this study. With the otherwise non-endocytosable large 2D materials gaining access to cytosol, potent intracellular signaling or theranostic platform that surpasses the intrinsic performance limit of conventional small counterparts are in sight.

8.
Angew Chem Int Ed Engl ; 60(50): 26072-26079, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34545677

RESUMO

A bis(pyridyl)amine-bipyridine-iron(II) framework (Fe(BPAbipy)) of complexes 1-3 is reported to shed light on the multistep nature of CO2 reduction. Herein, photocatalytic conversion of CO2 to CO even at low CO2 concentration (1 %), together with detailed mechanistic study and DFT calculations, reveal that 1 first undergoes two sequential one-electron transfer affording an intermediate with electron density on both Fe and ligand for CO2 binding over proton. The following 2 H+ -assisted Fe-CO formation is rate-determining for selective CO2 -to-CO reduction. A pendant, proton-shuttling α-OH group (2) initiates PCET for predominant H2 evolution, while an α-OMe group (3) cancels the selectivity control for either CO or H2 . The near-unity selectivity of 1 and 2 enables self-sorting syngas production at flexible CO/H2 ratios. The unprecedented results from one kind of molecular catalyst skeleton encourage insight into the beauty of advanced multi-electron and multi-proton transfer processes for robust CO2 RR by photocatalysis.

9.
Ann Transl Med ; 9(16): 1295, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532432

RESUMO

Background: Hepatic steatosis creates a significant risk of liver resection and transplantation and is extremely susceptible to ischemia/reperfusion (I/R) injury. Ischemic postconditioning (IPostC) has been shown to attenuate I/R injury in normal livers; however, its role in steatotic livers remains unknown. The current study sought to explore whether IPostC could attenuate normothermic I/R injury in rats with steatotic livers and to investigate potential protective measures. Methods: Hepatic steatosis was triggered in Wistar rats fed high-fat diets. The role of IPostC was detected in normal and steatotic livers with 30 min of ischemia and 6 h of reperfusion. Blood and liver tissues were collected to assess hepatocyte damage, lipid peroxidation, inflammatory factors, neutrophil accumulation, and adenosine triphosphate (ATP) content. Results: Compared to normal livers, steatotic livers were more susceptible to I/R damage, as evidenced by incremental concentrations of liver enzymes in the blood and more severe pathological changes in the liver. Hepatic I/R injury was significantly reduced by IPostC in both normal and steatotic livers. We further found that endogenous protective measures moderated lipid peroxidation, inflammatory cytokine expression and neutrophil accumulation, and reduced follow-up hepatic injury. The ATP content of steatotic livers was also significantly lower than that of Normal livers before and after I/R injury. IPostC greatly preserved the ATP content of normal and steatotic livers with I/R injury. Conclusions: IPostC appears to provide important protection against hepatic I/R injury in normal and steatotic livers under normothermic conditions. These data have important clinical implications for liver surgery and transplantation.

11.
ChemSusChem ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34532988

RESUMO

Al-based batteries are promising next-generation rechargeable batteries owing to the abundance of raw materials and their high potential energy density. The Al-S system has attracted considerable attention because of its high energy density and low cost. However, its low discharge voltage plateau (0.6-1.2 V) hampers its practical application. Herein, eight ionic liquids or deep eutectic solvents were studied as electrolyte candidates for an Al-S cell. This was the first study to demonstrate that an Al-S cell based on an AlCl3 /acetamide electrolyte (1.3 molar ratio) showed high discharge voltage plateaus (1.65-1.95 V) and a charging cut-off voltage of 2.5 V in Al-S cells. An Al-S cell of 0.33 mAh capacity with the AlCl3 /acetamide electrolyte successfully lit up a red LED (forward voltage 1.6-2.0 V) for around 2 h. This work may help in promoting the development of high-performance and low-cost Al-S cells.

12.
Sensors (Basel) ; 21(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502728

RESUMO

The suspended monorail (SM) vehicle-bridge system has been considered a promising modern transit mode due to its clear advantages: low pollution, high safety, convenient construction, and low cost. The wind-induced response can significantly affect the running safety and comfort of this type of vehicle due to its special suspended position from a fixed track. This study is the first to systematically investigate its aerodynamic characteristics and interference effects under various spacing ratios using wind tunnel tests and numerical simulations. A high level of agreement between the wind tunnel test and CFD (computational fluid dynamics) results was obtained, and the aerodynamic interference mechanism can be well explained using the CFD technique from a flow field perspective. A wireless wind pressure acquisition system is proposed to achieve synchronization acquisition for multi wind pressure test taps. The paper confirms that (1) the proposed wireless wind pressure acquisition system performed well; (2) the aerodynamic coefficients of the upstream vehicle and bridge were nearly unchanged for vehicle-bridge combinations with varying spacing ratios; (3) the aerodynamic interference effects were amplified when two vehicles meet, but the effects decrease as the spacing ratio increases; (4) the aerodynamic force coefficients, mean, and root mean square (RMS) wind pressure coefficients for the downstream vehicle and bridge are readily affected by the upstream vehicle; (5) the vortex shedding frequencies of vehicles and bridges can be readily obtained from the lift force spectra, and they decrease as the spacing ratio increases; and (6) a spacing ratio of 3.5 is suggested in the field applications to ensure the running safety and stability of the SM vehicle-bridge system under exposure to crosswinds.

13.
Aging Cell ; 20(10): e13482, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34582091

RESUMO

Aging has many effects on the female reproductive system, among which decreased oocyte quality and impaired embryo developmental potential are the most important factors affecting female fertility. However, the mechanisms underlying oocyte aging are not yet fully understood. Here, we selected normal reproductively aging female mice and constructed a protein expression profile of metaphase II (MII) oocytes from three age groups. A total of 187 differentially expressed (DE) proteins were identified, and bioinformatics analyses showed that these DE proteins were highly enriched in RNA splicing. Next, RNA-seq was performed on 2-cell embryos from these three age groups, and splicing analysis showed that a large number of splicing events and genes were discovered at this stage. Differentially spliced genes (DSGs) in the two reproductively aging groups versus the younger group were enriched in biological processes related to DNA damage repair/response. Binding motif analysis suggested that PUF60 might be one of the core splicing factors causing a decline in DNA repair capacity in the subsequent development of oocytes from reproductively aging mice, and changing the splicing pattern of its potential downstream DSG Cdk9 could partially mimic phenotypes in the reproductively aging groups. Taken together, our study suggested that the abnormal expression of splicing regulation proteins in aged MII oocytes would affect the splicing of nascent RNA after zygotic genome activation in 2-cell embryos, leading to the production of abnormally spliced transcripts of some key genes associated with DNA damage repair/response, thus affecting the developmental potential of aged oocytes.

14.
J Healthc Eng ; 2021: 4543702, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336152

RESUMO

The clinical characteristics and vascular computed tomography (CT) imaging characteristics of patients were explored so as to assist clinicians in diagnosing patients with atherosclerosis. 316 patients with atherosclerosis who were hospitalized for emergency treatment were treated with rapamycin (RAPA) in the hospital. A group of manually delineated left ventricular myocardia (LVM) on the patient's coronary computed tomography angiography (CCTA) were selected as the region of interest for imaging features extracted. The CCTA images of 80% of patients were randomly selected for training, and those of 20% of patients were used for verification. The correlation matrix method was used to remove redundant image omics features under different correlation thresholds. In the validation set, CCTA diagnostic parameters were about 40 times higher than the manually segmented data. The average dice similarity coefficient was 91.6%. The proposed method also produced a very small centroid distance (mean 1.058 mm, standard deviation 1.245 mm) and volume difference (mean 1.640), with a segmentation time of about 1.45 ± 0.51 s, compared to about 744.8 ± 117.49 s for physician manual segmentation. Therefore, the deep learning model effectively segmented the atherosclerotic lesion area, measured and assisted the diagnosis of future atherosclerosis clinical cases, improved medical efficiency, and accurately identified the patient's lesion area. It had great application potential in helping diagnosis and curative effect analysis of atherosclerosis.

15.
J Diabetes Res ; 2021: 5495219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34368364

RESUMO

Background: Relative to nondiabetic patients, percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM) is associated with inferior clinical outcomes. We aimed to evaluate the outcomes of drug-coated balloon (DCB) in diabetic versus nondiabetic patients. Methods and Results: In this observational, prospective, multicenter study, we compared the outcomes of patients with and without DM after undergoing PCI with DCBs. Target lesion failure (TLF) was analyzed as primary endpoint. Secondary endpoints were the rates of target lesion revascularization (TLR), major adverse cardiovascular events (MACE), cardiac death, myocardial infarction (MI), and any revascularization. Propensity score matching was used to assemble a cohort of patients with similar baseline characteristics. Among 2,306 eligible patients, 578 with DM and 578 without DM had similar propensity scores and were included in the analyses. During follow-up (366 ± 46 days), compared with DM patients, patients without DM were associated with a lower yearly incidence of TLF (2.77% vs. 5.36%; OR, 1.991; 95% CI, 1.077 to 3.681; P = 0.025) and TLR (1.90% vs. 4.15%; OR, 2.233; 95% CI, 1.083 to 4.602; P = 0.026). No significant differences were observed with regards to rates of MACE (OR: 1.580, 95% CI: 0.912-2.735; P = 0.100), cardiac death (OR: 1.608, 95% CI: 0.523-4.946; P = 0.403), MI (OR: 4.042, 95% CI: 0.855-19.117; P = 0.057), and any revascularization (OR: 1.534, 95% CI: 0.983-2.393; P = 0.058). Conclusions: Diabetic patients experience higher TLF and TLR rates following DCB angioplasty without substantial increase in the risk of MACE, cardiac death, MI, or revascularization.

16.
Hum Exp Toxicol ; : 9603271211036037, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372727

RESUMO

Background: Several recent studies have suggested that the long non-coding RNA (lncRNA) DSCAM-AS1 (Down syndrome cell adhesion molecule - anti-sense 1) is aberrantly expressed in many malignancies. Purpose: In this study, we aimed to explore the the role of DSCAM-AS1 in gastric carcinoma. Research Design: Expression of DSCAM-AS1 mRNA, miR-204, and TPT1 (Tumor Protein, Translationally-Controlled 1) were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Proliferation and apoptosis of GC cells were determined using the CCK-8 cell counting assay and flow cytometry. The rate of cell migration and invasion was determined using a transwell assay. The relationships between DSCAM-AS1, miR-204, and TPT1 were predicted and confirmed using a dual-luciferase reporter assay. Expression of TPT1 protein was quantified by Western blot. Results: In this study, we found that DSCAM-AS1 was significantly overexpressed in GC tissues and cell lines. Functional experiments indicated that GC cells with DSCAM-AS1 silencing exhibited a dynamic reduction in proliferation and migration. We identified miR-204 as a target of DSCAM-AS1 and found that it targeted TPT1 in GC cells, which further led to decreased expression of miR-204 in GC tissues and cell lines. A rescue assay revealed that knocked-down DSCAM-AS1 hindered GC progression, which was reversed upon miR-204 downregulation or TPT1 overexpression. Conclusion: We conclude that DSCAM-AS1 is expressed as a tumor oncogene in GC progression, modulated via the miR-204/TPT1 axis. These findings indicate the potential of DSCAM-AS1 as a therapeutic target for GC prevention.

17.
Org Biomol Chem ; 19(34): 7432-7437, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34397075

RESUMO

A highly efficient cyanosilylation protocol mediated by the easily available n-BuLi with a wide range of aldehydes and ketones was developed. This protocol features excellent yields with very low n-BuLi loadings (0.01-0.05 mol%) at room temperature, solvent-free process, good chemo-/regio-selectivity and functional group tolerance and scalability. A possible reaction pathway based upon stoichiometric reactivity was put forward.

18.
J Prim Care Community Health ; 12: 21501327211039715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34412529

RESUMO

BACKGROUND: Self-rated health (SRH) is a common measure of overall health. However, little is known about multilevel correlates of physical and mental SRH. METHODS: Patients attending primary care clinics completed a survey before their appointment, which we linked to community data from American Community Survey and other sources (n = 455). We conducted multilevel logistic regression to assess correlates of excellent/very good versus good/fair/poor physical and mental SRH. RESULTS: 43.9% of participants had excellent/very good physical SRH, and 55.2% had excellent/very good mental SRH. Physical SRH was associated with age (odds ratio[OR] = 0.82 per 10 years; 95% confidence interval[CI] = 0.72-0.93) and community correlates, including retail establishment density (OR = 0.94, 95% CI = 0.90-0.99) and percent of students eligible for free/reduced lunch (OR = 1.60, 95% CI = 1.08-2.38) (all P < .05). Mental SRH was not associated with any characteristics. CONCLUSIONS: Practitioners in public health, social work, and medicine could use zip codes to intervene in patients and communities to improve physical SRH.


Assuntos
Nível de Saúde , Estudantes , Criança , Humanos , Inquéritos e Questionários
19.
Macromol Rapid Commun ; 42(20): e2100394, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34418207

RESUMO

Covalent adaptable networks (CANs) have recently received extensive interests due to their reprocessability and repairability. Rethinking the libraries of the published CANs, most of them are fabricated by one/two-component reactions and few cases utilize multi-component reactions to construct CANs while multi-component reactions are conductive to tailoring the properties of polymers due to their structural designability and flexible choice of raw materials. A novel kind of dynamic covalent bond named aminoesterenamide is presented through three-component reaction between acetoacetyl, amine and isocyanate. Aminoesterenamide exhibits thermal reversibility through dissociating into vinylogous urethane and isocyanate. When it is used to prepare CANs, the synthesized polymer networks can be reprocessed many times via the exchange reaction between aminoesterenamides. Moreover, the forming of aminoesterenamide involving three starting components imparts CANs with great freedom to tailor their properties. Therefore, the authors believe this method that utilizes three-component reaction to fabricate CANs would bring new stories and perspectives to the exploration of new types of CANs.


Assuntos
Polímeros , Uretana , Aminas , Condutividade Elétrica
20.
Food Funct ; 12(17): 8017-8025, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34269784

RESUMO

The purpose of this study was to investigate the effect of starch-hydrocolloid (gum arabic, xanthan gum, and guar gum) complexes with heat-moisture treatment (HMT) on in vivo digestibility. In vivo digestibility experiments revealed that the body weight, liver weight, and fat index of mice in the intervention group were significantly reduced compared with those in the high-fat group. Glucose tolerance improved, and blood lipid levels, liver and adipose tissue morphology returned to normal. The results of mRNA expression levels showed that the intervention of corn starch-hydrocolloid complexes after HMT down-regulated the expression level of genes related to fat synthesis compared with the high-fat group, which could decrease lipid deposition and stabilize blood lipid levels. Results revealed that starch-xanthan gum complex (1 : 40 ratio) with HMT could markedly reduce the digestibility of starch. Overall, this study provides new ideas for the application of low-glycemic-index and functional foods.

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