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1.
Food Chem ; 366: 130712, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343953

RESUMO

The aim of this study was to investigate the effect of selenium enrichment on the gel properties and gastrointestinal digestive properties of egg white. Results of texture profile analysis, scanning electron microscopy and differential scanning calorimetry showed that the heat-induced gel of selenium-enriched egg white (EW-2) exhibited higher gel strength, smoother microstructure, and higher thermal denaturation temperature than ordinary egg white (EW-1), which might be due to the change of ovomucin and ovotransferrin content. The gastrointestinal digestive products of the EW-2 protein contained a higher proportion of small peptides and more free amino acids than those of EW-1. Results of oxygen radical absorbance capacity and cellular antioxidant activity assays indicated that digestive products of the EW-2 protein exhibited stronger antioxidant activity than those of the EW-1 protein. In summary, Se enrichment improved heat-induced gel properties of egg white, and promoted the gastrointestinal digestion of egg white protein.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34469033

RESUMO

Nitrogen substituted alkynes such as ynamines and ynamides are versatile synthetic building blocks in organic chemistry. Ynimines bearing additional nucleophilic and electrophilic centers relative to ynamines and ynamides are expected to have high synthetic potential. However, their chemical reactivity remains unexplored due mainly to the lack of synthetic accessibility. We report herein a versatile Cu-catalyzed synthesis of ynimines from readily available O-acetyl ketoximes and terminal alkynes. A wide range of O-acetyl ketoximes derived from diaryl ketones, aryl alkyl ketones and dialkyl ketones undergo cross-coupling with a diverse set of terminal alkynes to afford the ynimines in good to excellent isolated yields. An unprecedented [5+1] heteroannulation reaction exploiting the reactivity of the in situ generated ynimine is subsequently developed for the synthesis of medicinally important heterocycles including isoquinolines, aza-indoles, aza-benzofurans, aza-benzothiophenes and carbolines. We anticipate that this robust synthesis of ynimines would open an avenue for the exploration of this functionally rich building block .

3.
Expert Rev Vaccines ; : 1-9, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34488546

RESUMO

INTRODUCTION: The Delta variant of SARS-CoV-2 has caused a new wave of the COVID-19 epidemic in many countries. It is the most infectious variant of SARS-CoV-2 to date, and its high infectivity means that a higher proportion of the population needs to be vaccinated to reduce the disease burden, which poses a substantial public health challenge. AREAS COVERED: The evolution of the Delta variant is reviewed, including an overview of the Delta Plus variant with a K417N mutation in the RBD, which may confer an improved immune evasion ability. Decreases in serum neutralizing antibody titers after vaccination against Delta were greater than those against Alpha but less than those against Beta. The protective efficacy of existing vaccines against the Delta variant have declined and is related to the number of doses and the time since vaccination. EXPERT OPINION: The currently used vaccines are effective against hospitalization/severe disease due to the Delta variant. Accelerating the popularization of vaccination, improving the coverage rate, and the implementation of intervention measures, such as wearing masks, are effective means to control the spread of the Delta variant and other variants. However, vaccination alone against SARS-CoV-2 without intervention measures may lead to continuous spread and the emergence of new variants.

4.
J Hazard Mater ; 416: 125824, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492786

RESUMO

Extracellular polymeric substances (EPSs) constitute a largely global carbon pool that could participate in geochemical process of organic chemicals. Besides the chemical hydrolysis and redox of chemicals exerted by the EPS, weakly noncovalent interactions with dispersive EPS control the toxicity of numerous organic compounds. Nevertheless, there has been a lack of in-depth research on this issue. This work quantified a chain of links from bonding to detoxification using natural biofilms to explore the control behavior of fragile noncovalent bonding to the ecotoxicity of aromatic compounds. Such bonding decreases cell absorbability of m-phenylenediamine, 2-naphthol, and phenanthrene by 5.3-53.6%, resultantly increasing the indices of microbial diversity by 122.2-279.5%. Herein, the 60 kDa chaperonin in EPS acts as the most important contributor (16.4% of the top 20 proteins) to noncovalent interactions. Hydrophilic carboxyl groups in EPS bind with hydroxyl and amino groups of m-phenylenediamine and 2-naphthol via H-bonds, respectively. Methylene and carboxyl groups combine with hydrophobic phenanthrene via CH···π and H-bonding, respectively. A quantified chain was consequently established that weak interaction linearly controls ecotoxicity of aromatic compounds via the above suppressive cell absorbability of aromatic compounds (R2 =0.82). Considering ubiquitous EPS and prevailing aromatic compounds, our findings revealed a previously unnoticed phenomenon in which seemingly fragile noncovalent bonding profoundly alleviates the ecotoxicity of aromatic compounds in Earth's surface system.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Compostos Orgânicos , Biofilmes , Carbono , Interações Hidrofóbicas e Hidrofílicas
5.
Medicine (Baltimore) ; 100(35): e26929, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477124

RESUMO

ABSTRACT: In traditional Chinese medicine (TCM), Yu-Ping-Feng powder (YPFP) has been used to treat allergic rhinitis (AR) for centuries. However, the mechanisms underlying its effects or its molecular targets in AR treatment are yet to be elucidated. Therefore, the active compounds of YPFP and their targets were collected and identified from the Traditional Chinese Medicine Systems Pharmacology database. Moreover, AR-associated targets were acquired from the GeneCards and Online Mendelian Inheritance in Man database. Proteins interactions network of YPFP presumed targets and AR-associated targets were examined and merged to reveal the candidate YPFP targets against AR.Cytoscape software and BisoGenet Database were employed to perform the Visualization and Integrated Discovery (Cluster Profiler R package, version: 3.8.1). Kyoto Encyclopedia of Genes and Genomes and genome pathway analyses. To identify the key target genes, a gene-pathway network has been constructed.We identified 44 effective active compounds and 622 YPFP targets. Also 1324 target genes related to AR were identified. Twenty pathways, including those of AGE-RAGE signaling, fluid shear stress, atherosclerosis, PI3K-Akt signaling, and tumor necrosis factor signaling was enriched significantly. MAPK1 was identified as the core gene, while others including RELA, AKT1, NFKBIA, IL6, and JUN, were also important in the gene-pathway network. Clearly, network pharmacology can be applied in revealing the molecular targets and mechanisms of action of complex herbal preparations.These findings suggested that YPFP could treat AR by regulating immunological functions, diminishing inflammation, and improving immunity through different pathways.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Farmacologia/métodos , Rinite Alérgica/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Mapas de Interação de Proteínas/efeitos dos fármacos
6.
Ecotoxicol Environ Saf ; 225: 112734, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34482065

RESUMO

Cadmium (Cd), a phytotoxic heavy metal accumulated in plants and fruits, has significant adverse effects on plant growth and development as well as human health. In particular, Cd pollution has become a serious agricultural issue in recent years. Apple is one of the most popular fruits consumed at the global scale. Improving apple Cd resistance via reductions in Cd absorption can benefit apple tree growth and ensure fruit safety. In this study, we determined that, under the 200 µM Cd treatment, 35S::MdIAA24 apple plants exhibited more biomass and less Cd accumulation in the tested tissues compared to wild type (WT). Furthermore, the 35S::MdIAA24 apple plants demonstrated more favorable photosynthesis characteristics, less reactive oxygen species (ROS) and a greater amount of active antioxidant enzymes under the Cd condition than WT. The expression levels of the Cd uptake genes were observed to be lower in the 35S::MdIAA24 apple plants compared with those of the WT under the Cd treatment. The results highlight the ability of the overexpression of MdIAA24 to enhance apple Cd resistance by improving antioxidant capacity and reducing Cd absorption.

7.
Org Biomol Chem ; 19(36): 7867-7874, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34492676

RESUMO

A visible light mediated stereospecific C(sp2)-H difluoroalkylation of (Z)-aldoximes to (E)-difluoroalkylated ketoximes has been described. In this reaction, (hetero)-aromatic and aliphatic difluoroalkylated ketoximes could be obtained with the retention of the configuration of the starting aldoximes. A preliminary mechanism study showed that a difluoromethyl radical via an SET pathway was involved.

8.
BMC Immunol ; 22(1): 60, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479503

RESUMO

BACKGROUND: Immune checkpoint inhibitors have aroused great expectation of tumor eradication. However, the effect of anti-PD-L1 treatment for cervical cancer is unsatisfactory and the underlying antagonist to anti-PD-L1 efficacy is remained to be studied. Here, we investigated the anti-tumor effect of anti-PD-L1 treatment in cervical tumor model and identified the antagonist to the therapeutic efficacy of anti-PD-L1 treatment. RESULTS: We found that PD-L1 exhibited a moderate expression in both cervical tumor cell lines and clinical samples compared to other tumor types and the para-tumor tissue respectively. Interestingly, our results showed that the anti-PD-L1 treated mice were dichotomously divided into responsive and unresponsive group after five cycles of anti-PD-L1 treatment although all the mice had the same genome background. In addition, the unresponsive tumors showed less tumor necrosis area and higher immunosuppression activity induced by regulatory T cells (Tregs) population than the responsive ones. Furthermore, we found that anti-PD-L1 treatment autonomously upregulated Tregs proliferation and frequency in multiple immune organs, and, most importantly, Tregs depletion significantly depressed the tumor growth rate and tumor weight compared with either anti-PD-L1 or anti-CD25 treatment alone. Finally, we observed that the upregulating effector CD8+ T cell is associated with the better therapeutic effect of anti-PD-L1 therapy post Tregs depletion. CONCLUSIONS: Anti-PD-L1 treatment upregulates Tregs frequency and proliferation in tumor model, and the depletion of Tregs may be a useful adjuvant strategy for anti-PD-L1 therapy of cervical cancer.

9.
Appl Spectrosc ; : 37028211042903, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34505818

RESUMO

This paper describes a data preprocessing algorithm that can be used to mitigate the effects of interfering spectral components when the goal is to detect the spectrum of unknown components in a mixture of known components or to verify the presence of suspected components in the spectrum of a mixture of known components. The algorithm is both relatively simple and applicable to a wide range of problems in spectroscopy. The range of applicability can be increased by combining the method with other data preprocessing methods, for example derivative spectra, and can also accommodate variability in the spectra of one or more of the known components. Examples of the application of the algorithm to real problems are given for near-infrared analysis of antibiotic drug formulations inside gelatin capsules and mid-infrared analysis of atmospheric pollutants.

10.
J Pharmacol Exp Ther ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465632

RESUMO

Acute respiratory distress syndrome (ARDS), a common and fatal clinical condition, is characterized by the destruction of epithelium and augmented permeability of the alveolar-capillary barrier. Resolvin conjugates in tissue regeneration (RCTR1) is an endogenous lipid mediator derived from DHA, exerting pro-resolution effects in the process of inflammation. In our research, we evaluated the role of RCTR1 in alveolar fluid clearance (AFC) in Lipopolysaccharide-induced ARDS/ALI rat model. Rats were injected with RCTR1 (5 µg/kg) via caudal veins 8h after LPS (14 mg/kg) treatment, then AFC was estimated after 1h of ventilation. Primary type II alveolar epithelial cells (AEC II) were incubated with LPS (1 ug/ml) with or without RCTR1 (10 nM) for 8 h. Our results showed that RCTR1 significantly enhanced the survival rate, promoted the AFC, and alleviated LPS-induced ARDS/ALI in vivo. Furthermore, RCTR1 remarkably elevated the protein expression of sodium channels and Na, K-ATPase, and the activity of Na, K-ATPase in vivo and in vitro. Additionally, RCTR1 also decreased Nedd4-2 level via up-regulating P-Akt expression. Besides, inhibitors of ALX, cAMP, and PI3K (BOC-2, KH-7, and LY294002) notably inhibited the effects of RCTR1 on AFC. In summary, RCTR1 enhances the protein levels of sodium channels and Na, K-ATPase, and the Na, K-ATPase activity to improve AFC in ALI through ALX/cAMP/PI3K/Nedd4-2 pathway, suggesting that RCTR1 may become a therapeutic drug for ARDS/ALI. Significance Statement 1.RCTR1, an endogenous lipid mediator, enhanced the rate of AFC to accelerate the resolution of inflammation in the LPS-induced murine lung injury model. 2. RCTR1 up-regulates the expression of ENaC and Na, K-ATPase in vivo and in vitro to accelerate the AFC. 3. The efficacy of RCTR1 on the ENaC and Na, K-ATPase level was in an ALX/cAMP/PI3K/Nedd4-2-dependent.

11.
J Hazard Mater ; 416: 126042, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492889

RESUMO

Bottom ash (BA) management is often implemented through its co-disposal with municipal solid waste (MSW) in landfills. However, BA co-disposal may lead to heavy metal leaching in landfills. In this study, the effect of BA co-disposal on heavy metal leaching behavior under different scenarios, specifically, MSW, low BA co-disposal (BA_L), high BA co-disposal (BA_H), and BA monofill were investigated. The heavy metal concentrations in the leachate decreased in landfills over time. The leached metals primarily included Zn, Cu, Mn, Pb, Cr, and Cd. The discharge concentration ratio of heavy metals in the leachates exhibited the following decreasing order: MSW, BA_L, BA_H, and BA. In particular, the discharge concentration ratio of Cu in the MSW, BA_L, BA_H, and BA cases ranged from 7.1 × 10-3 to 8.8 × 10-1 (mean = 3.0 ×10-1), 2.8 × 10-4 to 2.0 × 10-1 (mean = 5.4 ×10-2), 9.1 × 10-5 to 3.0 × 10-2 (mean = 5.9 ×10-3), and 4.4 × 10-4 to 7.9 × 10-3 (mean = 1.8 ×10-3), respectively. Moreover, the leaching of the heavy metals could be attributed to waste contents, properties of the heavy metals, and leachate characteristics, such as the pH, chemical oxygen demand (COD), alkalinity, and Cl- content. The presented findings can help clarify the leaching characteristics of heavy metals in BA co-disposal landfills, thereby facilitating the optimization of practical landfills.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Incineração , Metais Pesados/análise , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos
12.
Genome Biol ; 22(1): 271, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544450

RESUMO

LightGBM is an ensemble model of decision trees for classification and regression prediction. We demonstrate its utility in genomic selection-assisted breeding with a large dataset of inbred and hybrid maize lines. LightGBM exhibits superior performance in terms of prediction precision, model stability, and computing efficiency through a series of benchmark tests. We also assess the factors that are essential to ensure the best performance of genomic selection prediction by taking complex scenarios in crop hybrid breeding into account. LightGBM has been implemented as a toolbox, CropGBM, encompassing multiple novel functions and analytical modules to facilitate genomically designed breeding in crops.

13.
BMC Neurol ; 21(1): 364, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34536997

RESUMO

BACKGROUND: Few studies have investigated the influence of white matter lesions (WMLs) on the prognosis of acute cardioembolic stroke (CES). We aimed to explore the role of WMLs in predicting 3-month prognosis of CES without reperfusion therapy. METHODS: A number of 251 acute CES patients without reperfusion therapy at a single center were retrospectively recruited. The severity of WMLs was evaluated by Fazekas scale and patients were divided into mild WMLs group (188 cases, Fazekas ≤ 2 points) and moderate to severe WMLs group (63 cases, Fazekas ≥ 3 points) accordingly. General data and clinical features of the two groups were compared. Functional outcomes of patients were followed up for 3 months using the modified Rankin scale (mRS) and patients were divided into poor outcome group (mRS ≥ 3) and favorable outcome group (mRS ≤ 2). The effect of WMLs on the prognosis was identified by binary logistic regression. RESULTS: Patients in moderate to severe WMLs group were older (P < 0.001). Also, they had higher baseline National Institutes of Health Stroke Scale (NIHSS) score (P < 0.001) and elevated incidence of asymptomatic cerebral hemorrhage (P = 0.040) and stroke associated pneumonia (P = 0.001) than those in mild WMLs group. At 3 months, there were 100 cases in the poor outcome group. Patients in poor outcome group had higher baseline NIHSS score, increased proportion of moderate to severe WMLs, and elevated incidence of stroke associated pneumonia than those in favorable outcome group (P < 0.001). Binary logistic regression analysis showed that moderate to severe WMLs (odds ratio [OR] = 4.105, 95 % confidence interval [CI] = 1.447-11.646), baseline NIHSS score (OR = 1.368, 95 % CI = 1.240-1.511), and stroke-associated pneumonia (OR = 4.840, 95 %CI = 1.889-12.400) were independent risk factors for poor outcome. CONCLUSIONS: Moderate to severe WMLs is an independent risk factor for prognosis of CES patients without reperfusion therapy.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34542824

RESUMO

Stroke remains a highly deadly and disabling disease with limited treatment tragedies due to the limitations of available treatments; novel therapies for stroke are needed. In this article, the synergistic results of dual bone marrow mesenchymal stem cells (BMSC) and fasudil treatment in rat models of ischemic stroke still require further identification. Sprague-Dawley rats were used to construct the middle cerebral artery, occlusion models. BMSCs were incubated with fasudil, and MTT was performed to evaluate cell proliferation. The rats were treated with fasudil + BMSC, BMSC, fasudil, and saline. Blood samples were collected for complete blood count analysis and measurement of serum TNF-α levels. The neurological functions were evaluated. After the rats were sacrificed, immunohistochemical staining and TTC staining was performed. Fasudil promoted the proliferation of BMSCs and induced their differentiation into neuron-like cells. BMSCs increased the proportion of neutrophils; nevertheless, fasudil counteracted the neutrophil increase. The TUJ-1/MAP2/VIII factor expression in the fasudil + BMSC group was significantly higher than that in the other groups. The number of GFAP-positive cells decreased in the fasudil + BMSC and BMSC alone groups. The infarct volume in the fasudil + BMSC and BMSC alone groups was significantly lower than in the fasudil alone and control groups. Both BMSCs and fasudil exert neurorestorative effects in rat models of cerebral ischemia. Fasudil neutralizes the pro-inflammatory effects of BMSCs, while BMSCs and fasudil together had synergistic effects promoting neurovascular remodeling and neurological function recovery in stroke. A combination of BMSCs and fasudil provides a promising method for the treatment of ischemic stroke.

15.
Chembiochem ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34542923

RESUMO

Cytochrome P450 enzymes (P450s, CYPs) catalyze the oxidative transformation of wide range of organic substrates. Their functions are crucial to xenobiotic metabolism and steroid transformation in human and other organisms. The enzymes are promising for synthetic biology applications but limited by several drawbacks including low turnover rates, poor stability, the dependance of expensive cofactors and redox partners, and the narrow substrate scope. To conquer these obstacles, emerging strategies including substrate engineering, usage of decoy and decoy-based small molecules auxiliaries, designing of artificial enzyme cascades and the incorporation of materials have been explored based on the unique properties of P450s. These strategies can be applied to a wide range of P450s and be combined with protein engineering to improve the enzymatic activities. Herein, this minireview will focus on some recent developments of these strategies which have been used to leverage the P450 catalysis. Remaining challenges and future opportunities will also be discussed.

16.
Neurosurg Focus ; 51(3): E9, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34469867

RESUMO

OBJECTIVE: This prospective study was designed to confirm the role of atorvastatin in collateral circulation formation induced by encephaloduroarteriosynangiosis (EDAS) in patients with moyamoya disease (MMD). METHODS: Patients who were diagnosed with MMD at the Department of Neurosurgery in the Fifth Medical Center of Chinese PLA General Hospital, Beijing, China, between June 2017 and May 2018 were included. Blood samples were obtained from an antecubital vein and were analyzed using flow cytometry. Endothelial progenitor cells (EPCs) were defined as CD34brCD133+CD45dimKDR+. All patients included in the study underwent EDAS. Patients voluntarily chose whether to undergo atorvastatin treatment after EDAS. The correlation between atorvastatin and good postoperative collateral circulation was evaluated. RESULTS: A total of 106 patients with MMD were included in this study. Fifty-three patients (50%) received atorvastatin treatment. The baseline characteristics did not display statistically significant differences between the atorvastatin-treated and non-atorvastatin groups. Seventy-eight (42.9%) of the 182 hemispheres investigated postoperatively were classified as grade A collateral circulation, 47 (25.8%) as grade B, and 57 (31.3%) as grade C. Multivariate analysis revealed that only atorvastatin was significantly correlated with good collateral circulation after EDAS (p = 0.041). CONCLUSIONS: The results of this prospective clinical trial have indicated that atorvastatin administered at 20 mg daily is safe and effective for the formation of postoperative collateral induced by EDAS.

17.
J Vis Exp ; (174)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34487124

RESUMO

Sentinel lymph node (SLN) mapping and biopsy is a promising technique for visualizing and evaluating lymph node status in cancer. This approach has been recommended for low-risk endometrial cancer (EC) patients by authoritative international guidelines, but it has not been performed broadly in China and worldwide. This work aims to describe detailed SLN mapping and biopsy procedures to promote the clinical application. SLN mapping and postoperative pathologic ultrastaging were conducted in a patient with low-risk EC using indocyanine green (ICG) dye to track the SLNs under laparoscopy and resecting them completely for ultrastaging. In conclusion, this protocol describes details of ICG injection, and SLN mapping and biopsy in EC patients based on the experiences gained during clinical practice.

18.
Curr Neurovasc Res ; 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488582

RESUMO

BACKGROUND: The association between atrial fibrillation (AF) and the prognosis of intravenous thrombolysis (IVT) in patients with acute ischemic stroke (AIS) is debated. Hypokalemia is highly prevalent in patients with AF. We aimed to investigate the effect of hypokalemia and AF on the prognosis of AIS patients following IVT. METHOD: AIS patients undergoing IVT were enrolled and divided into four groups: normokalemia and non-AF, normokalemia and AF, hypokalemia and non-AF, hypokalemia and AF. Logistic regression was applied to analyze the impact of hypokalemia, AF, and their combination on the prognosis of patients. RESULTS: The analysis included 567 patients, 184 with 3-month poor prognosis (modified Rankin Scale score of 3-6). Following adjustment of risk factors, hypokalemia and AF increased the risks for 3-month poor prognosis (adjusted Odds Ratios (aOR) = 4.97; 95% confidence interval (CI), 1.99-12.44, P =.001), early neurological deterioration (END) (aOR=7.98; 95% CI, 3.55-17.95, P <.001), 1-year poor prognosis (aOR=5.05; 95% CI, 1.99-12.81, P =.001), 1-year all-cause death (aOR =6.95; 95% CI, 2.35-20.56, P <.001). Patients with normokalemia and AF merely increased the risk of 1-year all-cause death (aOR=2.69; 95% CI, 1.10-6.61, P=.013). Patients with hypokalemia and non-AF were not associated with any poor prognosis. There were combined and interactive effects of hypokalemia with AF on the 3-month poor prognosis (P for interaction =.039) and END (P for interaction=.005). CONCLUSION: Hypokalemia and AF synergistically increased the risk of near-term poor prognosis, END, long-term poor prognosis, and all-cause death of AIS patients following IVT.

19.
Langmuir ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478307

RESUMO

Regulation of self-assembly morphology is an effective strategy to obtain advanced functional materials with expected properties. However, achieving remarkable morphological transformation by light irradiation is still a challenge. Herein, three simple spiropyran derivatives (SP1, SP2, and SP3) are constructed, achieving different degrees of morphological transformation from nanospheres to hollow tadpole-like structures (SP3), tubular structures (SP2), and microsheets (SP1) after ultraviolet light irradiation. Interestingly, the hollow tadpole-like structures (SP3) can further extend to Y-shaped or T-shaped tubular morphology. In the process, SP1, SP2, and SP3 can be isomerized from a closed-ring form (hydrophobicity) to an open-ring form (hydrophilicity) in different degrees, interacting differently with methanol solvent molecules. The formation of hollow structures or microsheets along with the isomerization of spiropyran derivatives contributes to the adjustment of the hydrophilicity of the interface. Therefore, SP1, SP2, and SP3 with photoregulated morphological transformation show promising applications in tunable interface materials.

20.
Sci Total Environ ; 803: 149887, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34487899

RESUMO

Microplastics (MPs) in marine environments have raised increasing concerns worldwide in recent years. China is one of the largest plastic producers in the world. In this review, available information on MPs in China Sea was reviewed, including studies on seawater, sediment, and biota. The status and limits of sampling methods of MPs were summarized, such as sampling tools, sampling volume, and depth of sampling. The analytical methods of MPs were outlined, such as sieving, density separation, purification, filtration, and visual sorting. The characteristics of MPs, such as abundances, sizes, shapes, polymer types, sources, and fates were analyzed. The abundances of MPs in China Sea varied from 0.1 to 27,840.0 items m-3 in seawater, and from 13.0 to 14,712.0 items kg-1 d.w. in sediments. Furthermore, MPs were mainly featured with sizes ranging from 0.001 to 0.5 mm, with colors of transparent and black, and polymer types of polypropylene and polyethylene. To promote research on MPs in China Sea, the sampling and analytical methods were insufficiently standardized and should be improved. As for microplastic (MP) pollution in China Sea, laws and regulations have already been established to manage and control plastic waste. Furthermore, several suggestions to control plastic pollution were as follows: (1) control marine plastic pollution at the source; (2) strengthen technological innovations; (3) urge people to minimize disposable plastic products in their daily lives; (4) strengthen international cooperation in the treatment of marine plastic waste.

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