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1.
Invest Ophthalmol Vis Sci ; 62(13): 7, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34643662

RESUMO

Purpose: Previous studies indicate that leukocytes, notably neutrophils, play a causal role in the capillary degeneration observed in diabetic retinopathy (DR), however, the mechanism by which they cause such degeneration is unknown. Neutrophil elastase (NE) is a protease released by neutrophils which participates in a variety of inflammatory diseases. In the present work, we investigated the potential involvement of NE in the development of early DR. Methods: Experimental diabetes was induced in NE-deficient mice (Elane-/-), in mice treated daily with the NE inhibitor, sivelestat, and in mice overexpressing human alpha-1 antitrypsin (hAAT+). Mice were assessed for diabetes-induced retinal superoxide generation, inflammation, leukostasis, and capillary degeneration. Results: In mice diabetic for 2 months, deletion of NE or selective inhibition of NE inhibited diabetes-induced retinal superoxide levels and inflammation, and inhibited leukocyte-mediated cytotoxicity of retinal endothelial cells. In mice diabetic for 8 months, genetic deletion of NE significantly inhibited diabetes-induced retinal capillary degeneration. Conclusions: These results suggest that a protease released from neutrophils contributes to the development of DR, and that blocking NE activity could be a novel therapy to inhibit DR.

2.
Phys Chem Chem Phys ; 23(40): 23124-23129, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34617082

RESUMO

This paper reports the fabrication and mechanical properties of macroscale graphene fibers (diameters of 10 to 100 µm with lengths upwards of 2 cm) prepared from a single sheet of single-layer graphene grown via chemical vapor deposition (CVD). The breaking strength of these graphene fibers increased with consecutive tensile test measurements on a single fiber, where fiber fragments produced from a prior test exhibited larger breaking strengths. Additionally, we observed an overall reduction of surface folds and wrinkles, and an increase in their alignment parallel to the tensile direction. We propose that a foundation of this property is the plastic deformations within the fiber that accumulate through sequential tensile testing. Through this cyclic method, our best fiber produced a strength of 2.67 GPa with a 1 mm gauge length.

3.
J Virol ; : JVI0130521, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643434

RESUMO

Interactions between the N-terminal (assembly) domain (NTD) and the linker region of the hepatitis B virus (HBV) capsid protein and the large (L) envelope protein are required for virion formation, which occurs via budding of cytoplasmic mature nucleocapsids (NCs) containing the relaxed circular (RC) DNA genome into an intracellular membrane compartment containing viral envelope proteins. L-capsid interactions also negatively regulates covalently closed circular (CCC) DNA formation, which occurs after RC DNA release from mature NCs and nuclear import. We have now found that L could increase RC DNA in cytoplasmic mature NCs that are destabilized due to mutations in the NTD or the linker, even in those that apparently fail to support secretion of complete virions extracellularly. Other mutations in the capsid linker could block the effects of L on both cytoplasmic NC DNA and nuclear CCC DNA. Furthermore, the maturity of RC DNA in cytoplasmic NCs that was enhanced by L or found in secreted virions was modulated by the capsid linker sequence. The level and maturity of the cytoplasmic RC DNA was further influenced by the efficiency of extracellular virion secretion dependent on viral genotype-specific envelope proteins. These results suggest that interactions between the capsid and envelope proteins regulate one or more steps during virion secretion beyond initial capsid envelopment, and highlights the critical role of the capsid linker in regulating capsid-envelope interaction, including the timing of envelopment during NC maturation. Importance Hepatitis B virus (HBV) is a major human pathogen causing serious liver diseases including cancer. The interactions between the HBV capsid and the large (L) envelope protein is required for formation of infectious viral particles and also negatively regulate formation of an HBV DNA episome in the host cell nucleus, which serves as the sole transcriptional template capable of supporting all viral gene expression to sustain HBV replication and therefore, is the molecular basis of HBV persistence. Here, we report evidence indicating that L-capsid interactions modulate the timing of formation of infectious HBV particles during replication and facilitate extracellular release following their formation. Furthermore, a short linker sequence in the capsid protein plays a critical role in these processes as well as controls the amplification of the nuclear episome. These findings inform fundamental mechanisms of HBV replication as well as antiviral development targeting the HBV capsid and DNA episome.

4.
Sci Total Environ ; : 150992, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662623

RESUMO

Although hormesis induced by heavy metals is a well-known phenomenon, the involved biological mechanisms are not fully understood. Zinc (Zn) is an essential micronutrient for wheat, an important crop contributing to food security as a main staple food; however, excessive Zn is detrimental to the growth of wheat. The aim of this study was to evaluate morphological and physiological responses of two wheat varieties exposed to a broad range of Zn concentrations (0-1000 µM) for 14 days. Hormesis was induced by Zn in both wheat varieties. Treatment with 10-100 µM Zn promoted biomass accumulation by enhancing the photosynthetic ability, the chlorophyll content and the activities of antioxidant enzymes. Increased root/shoot ratio suggested that shoot growth was severely inhibited when Zn concentration exceeded 300 µM by reducing photosynthetic ability and the content of photosynthetic pigments. Excessive Zn accumulation (Zn treatment of 300-1000 µM) in leaf and root induced membrane injuries through lipid peroxidation as malondialdehyde (MDA) content increased with increasing Zn concentration. The results show that MDA content was higher than other treatments by 16.1-151.1% and 15.0-88.3% (XN979) and 36.8-235.7% and 20.6-83.8% (BN207) in the leaves and roots under 1000 µM Zn treatment. To defend against Zn toxicity, ascorbate (AsA), glutathione (GSH), non-protein thiols (NPT) and phytochelatin (PC) content of both wheat varieties (except leaf GSH content of BN207) was increased, while, the activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and the content of soluble protein decreased by 300-1000 µM Zn. The results showed that AsA-GSH cycle and NPT and PC content of wheat seedlings play important roles in defending against Zn toxicity. This study contributes new insights into the physiological mechanisms underlying the hormetic response of wheat to Zn, which could be beneficial for optimizing plant health in changing environments and improving risk assessments.

5.
Front Cell Dev Biol ; 9: 717601, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650972

RESUMO

The tumor immune microenvironment (TIME) has been recognized to be associated with sensitivity to immunotherapy and patient prognosis. Recent research demonstrates that assessing the TIME patterns on large-scale samples will expand insights into TIME and will provide guidance to formulate immunotherapy strategies for tumors. However, until now, thorough research has not yet been reported on the immune infiltration landscape of glioma. Herein, the CIBERSORT algorithm was used to unveil the TIME landscape of 1,975 glioma observations. Three TIME subtypes were established, and the TIMEscore was calculated by least absolute shrinkage and selection operator (LASSO)-Cox analysis. The high TIMEscore was distinguished by an elevated tumor mutation burden (TMB) and activation of immune-related biological process, such as IL6-JAK-STAT3 signaling and interferon gamma (IFN-γ) response, which may demonstrate that the patients with high TIMEscore were more sensitive to immunotherapy. Multivariate analysis revealed that the TIMEscore could strongly and independently predict the prognosis of gliomas [Chinese Glioma Genome Atlas (CGGA) cohort: hazard ratio (HR): 2.134, p < 0.001; Gravendeel cohort: HR: 1.872, p < 0.001; Kamoun cohort: HR: 1.705, p < 0.001; The Cancer Genome Atlas (TCGA) cohort: HR: 2.033, p < 0.001; the combined cohort: HR: 1.626, p < 0.001], and survival advantage was evident among those who received chemotherapy. Finally, we validated the performance of the signature in human tissues from Wuhan University (WHU) dataset (HR: 15.090, p = 0.008). Our research suggested that the TIMEscore could be applied as an effective predictor for adjuvant therapy and prognosis assessment.

6.
Front Genet ; 12: 731625, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484309

RESUMO

Background: Bladder cancer (BC) is the most common tumor of the urinary system. Non-muscle-invasive bladder cancer (NMIBC) has a high recurrence rate after surgery, and patients with muscle-invasive bladder cancer (MIBC) have poor quality of life after radical surgery. Understanding the molecular mechanism of bladder cancer is helpful for providing a more appropriate treatment approach. Annexins are calcium-binding proteins and play an important role in different tumor cells. However, the role of the annexin family in bladder cancer has not been studied in detail. Methods: ONCOMINE, UALCAN, TIMER2.0, Kaplan-Meier Plotter, cBioPortal, and WebGestalt were utilized in this study. Results: ANXA2, ANXA3, ANXA4, ANXA8, and ANXA9 were significantly increased in bladder tumor tissues, while ANXA6, ANXA7, and ANXA11 were significantly decreased. ANXA1, ANXA2, ANXA3, ANXA5, ANXA6, ANXA7, and ANXA9 had prognostic value in bladder cancer. In addition, specific annexins were specifically expressed in different subtypes of MIBC and were related to the histological morphology of bladder tumors. ANXA1, ANXA2, ANXA3, ANXA5, ANXA6, ANXA7, and ANXA8 were highly expressed in basal-subtype MIBC, while ANXA4, ANXA9, ANXA10, and ANXA11 were mainly expressed in luminal-subtype MIBC. Finally, we analyzed the possible mechanisms of ANXAs in different subtypes of bladder cancer through GO and KEGG analyses and the correlation between ANXAs and immune infiltration in the tumor microenvironment. Conclusion: Taken together, our results indicate that annexins might play important roles in BC and have the potential to be used as markers for subtype classification.

7.
ASN Neuro ; 13: 17590914211043087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34579557

RESUMO

Maternal social stress among breastfeeding women can be adapted in chronic process. However, neuroendocrine mechanisms underlying such adaptation remain to be identified. Here, we report the effects of 2 hr/day unfamiliar male rat invasion (UMI) stress on maternal behaviors in lactating rats during postpartum day 8 (UMI8) to postpartum day 12 (UMI12). Rat dams at UMI8 presented signs of maternal anxiety, depression, and attacks toward male intruder. These changes partially reversed at UMI12 except the sign of anxiety. In the supraoptic nucleus (SON), UMI12 but not UMI8 significantly increased the expression of c-Fos and phosphorylated extracellular signal-regulated protein kinase 1/2. At UMI8 but not UMI12, length of glial fibrillary acidic protein (GFAP, astrocytic cytoskeletal element) filaments around oxytocin (OT) neurons was significantly longer than that of their controls; the amount of GFAP fragments at UMI12 was significantly less than that at UMI8. Expression of cystathionine ß-synthase (CBS, enzyme for H2S synthesis) at UMI12 was significantly higher than that at UMI8. CBS expression did not change significantly in the somatic zone of the SON but decreased significantly at the ventral glia lamina at UMI8. In brain slices of the SON, aminooxyacetate (a CBS blocker) significantly increased the expression of GFAP proteins that were molecularly associated with CBS. Aminooxyacetate also reduced the firing rate of OT neurons whereas Na2S, a donor of H2S, increased it. The adaptation during chronic social stress is possibly attributable to the increased production of H2S by astrocytes and the subsequent retraction of astrocytic processes around OT neurons.

8.
J Clin Med ; 10(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34575285

RESUMO

Some discrepancies have been observed in the diagnostic efficacy of multifocal visual evoked potential (mfVEP) when evaluating visual field defects in glaucoma patients. Therefore, we evaluated the diagnostic precision of the mfVEP in glaucoma to find its best diagnostic indicator. A systematic review and meta-analysis of quantitative studies published up to 1 April 2021 was performed. The methodological quality of the included articles was assessed. Publication bias analysis and heterogeneity tests were performed. The sensitivity, specificity and diagnostic odds ratio were calculated. The area under the curve (AUC) was calculated using the summary of receiver operating characteristics curve. Six studies with a total of 241 patients were included according to the inclusion and exclusion criteria. The AUC was 0.98. There was no evidence of publication bias or threshold effect. The pooled sensitivity and pooled specificity of the mfVEP amplitude for detection of visual field defects in all studies was 0.93 and 0.89, respectively. The positive and negative likelihood ratios of mfVEP amplitude were 6.56 and 0.08, respectively. The amplitude of mfVEP showed a good diagnostic precision in the prediction of visual field defects. Interocular mfVEP amplitude analysis can be a good diagnostic indicator for visual field study.

9.
Kidney Int ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34534552

RESUMO

Previous studies have suggested the role of CD4+Foxp3+ regulatory T cells (Tregs) in protection against kidney ischemia reperfusion injury via their immunosuppressive properties. Unfortunately, the associated mechanisms of Tregs in kidney ischemia reperfusion injury have not been fully elucidated. Semaphorin 4A (Sema4A) is essential for maintaining the immunosuppressive capacity of Tregs in tumors. However, whether Sema4A can alleviate kidney ischemia reperfusion injury through Tregs has not yet been demonstrated. Here, we investigated the effect and mechanism of Sema4A on the development of kidney ischemia reperfusion injury. Administration of recombinant human Sema4A-Fc chimera protein prior to ischemia reperfusion injury promoted the expansion and function of Tregs and decreased the accumulation of neutrophils and proinflammatory macrophages thereby attenuating functional and histological injury of the injured kidneys. Depletion of Tregs abrogated the protective effect of Sema4A on kidney ischemia reperfusion injury, suggesting Tregs as the main target cell type for Sema4A in the development of this injury. Mechanistically, Sema4A bound to neuropilin 1 (Nrp1), a cell surface receptor for Sema4A and other ligands and a key regulator of Tregs, which then promoted recruitment of phosphatase and tensin homologue and suppressed the Akt-mTOR pathway in Foxp3Cre mice but not in Nrp1f/fFoxp3Cre mice. Consistently, Treg-specific deletion of Nrp1 blocked the effect of Sema4A on the expansion and function of Treg cells. Thus, our results demonstrate that the Sema4A-Nrp1 axis alleviates the development of ischemia reperfusion injury by promoting the stability and function of Tregs in mouse kidneys.

10.
Opt Lett ; 46(18): 4610-4613, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525060

RESUMO

An efficient method is proposed for the calculation of the optical force of multiple nanoparticles. In this method, the optical force is calculated by integrating the Maxwell stress tensor (MST) over a closed surface encompassing the nanoparticle. The electromagnetic (EM) field required for evaluating the MST is computed with the coupling theory of quasinormal modes (QNMs), in which the EM field is expanded onto a small set of QNMs of each nanoparticle. Once these dominant modes, which are eigensolutions of source-free Maxwell equations with complex eigenfrequencies, are known, any variation of the interparticle distance, illumination polarization, or wavelength can be treated analytically. Comparisons with the full-wave numerical method demonstrate the accuracy and efficiency of the formalism. With the formalism, force maps are calculated at remarkable computation speed, providing a promising simulation tool for applications such as plasmon tweezer and photoinduced force microscopy.

11.
Crit Care ; 25(1): 320, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34461969

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a heterogeneous syndrome, and the identification of homogeneous subgroups and phenotypes is the first step toward precision critical care. We aimed to explore whether ARDS phenotypes can be identified using clinical data, are reproducible and are associated with clinical outcomes and treatment response. METHODS: This study is based on a retrospective analysis of data from the telehealth intensive care unit (eICU) collaborative research database and three ARDS randomized controlled trials (RCTs) (ALVEOLI, FACTT and SAILS trials). We derived phenotypes in the eICU by cluster analysis based on clinical data and compared the clinical characteristics and outcomes of each phenotype. The reproducibility of the derived phenotypes was tested using the data from three RCTs, and treatment effects were evaluated. RESULTS: Three clinical phenotypes were identified in the training cohort of 3875 ARDS patients. Of the three phenotypes identified, phenotype I (n = 1565; 40%) was associated with fewer laboratory abnormalities, less organ dysfunction and the lowest in-hospital mortality rate (8%). Phenotype II (n = 1232; 32%) was correlated with more inflammation and shock and had a higher mortality rate (18%). Phenotype III (n = 1078; 28%) was strongly correlated with renal dysfunction and acidosis and had the highest mortality rate (22%). These results were validated using the data from the validation cohort (n = 3670) and three RCTs (n = 2289) and had reproducibility. Patients with these ARDS phenotypes had different treatment responses to randomized interventions. Specifically, in the ALVEOLI cohort, the effects of ventilation strategy (high PEEP vs low PEEP) on ventilator-free days differed by phenotype (p = 0.001); in the FACTT cohort, there was a significant interaction between phenotype and fluid-management strategy for 60-day mortality (p = 0.01). The fluid-conservative strategy was associated with improved mortality in phenotype II but had the opposite effect in phenotype III. CONCLUSION: Three clinical phenotypes of ARDS were identified and had different clinical characteristics and outcomes. The analysis shows evidence of a phenotype-specific treatment benefit in the ALVEOLI and FACTT trials. These findings may improve the identification of distinct subsets of ARDS patients for exploration in future RCTs.


Assuntos
Fenótipo , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hidratação/métodos , Hidratação/normas , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Respiração com Pressão Positiva/métodos , Respiração com Pressão Positiva/normas , Reprodutibilidade dos Testes , Telemedicina/métodos , Telemedicina/estatística & dados numéricos
12.
Cardiovasc Toxicol ; 21(12): 973-983, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34410632

RESUMO

To investigate the efficacy of Slit2 in the rats with coronary heart disease (CHD). CHD model were constructed by feeding high-fat food and injecting with pituitrin in rat, followed by recombinant Slit2 treatment, and then the cardiac function was evaluated by echocardiography, and the indicators concerning the cardiomyocyte injury markers and lipoprotein status and oxidative stress were measured. The Slit2 expression in the heart tissues was identified by immunofluorescence. Enzyme-linked immunosorbent assay (ELISA) was carried out to detect inflammatory cytokines, H2DCFDA staining to determine the ROS generation in heart tissues, Masson trichrome staining to observe myocardial fibrosis, and qRT-PCR and Western blotting to detect gene and protein expressions. Slit2 decreased the levels of LDH, CK-MB, cTnI, TG, TC and LDL-C and increased HDL-C level in CHD rats. In the normal heart tissues, Slit2 expression was significantly lower in cardiomyocytes than cardiac fibroblasts. Furthermore, the expressions of VCAM-1, ICAM-1, fibronectin and TGF-ß1 were increased in the heart tissues of CHD rats with the obvious myocardial fibrosis, which were dose-dependently reversed by recombinant Slit2. In addition, recombinant Slit2 also dose-dependently increased the activity of NO, SOD, CAT and GSH-Px, and decreased TNF-α, IL-6, MCP-1, MDA and ROS in CHD rats. Slit2 was downregulated in myocardial tissue and plasma of CHD rats. Recombinant Slit2, by regulating the level of blood lipid, can relieve the myocardial fibrosis, inflammation and oxidative stress in CHD.

13.
Mol Pharmacol ; 100(5): 470-479, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34393108

RESUMO

We compared monotherapies and combinations of therapies that regulate G-protein-coupled receptors (GPCRs) with respect to their abilities to inhibit early stages of diabetic retinopathy (DR) in streptozotocin-diabetic mice. Metoprolol (MTP; 0.04-1.0 mg/kg b.wt./day), bromocriptine (BRM; 0.01-0.1 mg/kg b.wt./day), doxazosin (DOX; 0.01-1.0 mg/kg b.wt./day), or tamsulosin (TAM; 0.05-0.25 mg/kg b.wt./day) were injected individually daily for 2 months in dose-response studies to assess their effects on the diabetes-induced increases in retinal superoxide and leukocyte-mediated cytotoxicity against vascular endothelial cells, both of which abnormalities have been implicated in the development of DR. Each of the individual drugs inhibited the diabetes-induced increase in retinal superoxide at the higher concentrations tested, but the inhibition was lost at lower doses. To determine whether combination therapies had superior effects over individual drugs, we intentionally selected for each drug a low dose that had little or no effect on the diabetes-induced retinal superoxide for use separately or in combinations in 8-month studies of retinal function, vascular permeability, and capillary degeneration in diabetes. At the low doses used, combinations of the drugs generally were more effective than individual drugs, but the low-dose MTP alone totally inhibited diabetes-induced reduction in a vision task, BRM or DOX alone totally inhibited the vascular permeability defect, and DOX alone totally inhibited diabetes-induced degeneration of retinal capillaries. Although low-dose MTP, BRM, DOX, or TAM individually had beneficial effects on some endpoints, combination of the therapies better inhibited the spectrum of DR lesions evaluated. SIGNIFICANCE STATEMENT: The pathogenesis of early stages of diabetic retinopathy remains incompletely understood, but multiple different cell types are believed to be involved in the pathogenic process. We have compared the effects of monotherapies to those of combinations of drugs that regulate GPCR signaling pathways with respect to their relative abilities to inhibit the development of early diabetic retinopathy.

14.
Ann Palliat Med ; 10(7): 7486-7513, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34353038

RESUMO

BACKGROUND: JiaWeiSiWu granule (JWSWG) has been applied clinically for more than a decade, and the preliminary results show that blood pressure can be reduced while protecting the target organ at the same time. The purpose of this research is to study the pharmacological mechanism of JWSWG in treating hypertension using network pharmacology. METHODS: The chief active components, relevant targets, and the target genes of JWSWG were retrieved by the databases TCMSP and UniProt. The GeneCards database was used to obtain target genes of hypertension. Then, the target genes of hypertension and active components were intersected to discover the potential targets by which JWSWG acts on hypertension. Cytoscape software was employed to construct the "medicine-compound-target-disease" network. The STRING database was used to construct the protein-protein interaction network in order to screen the key target genes. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were analyzed by RGUI and org.Hs.eg.db. RESULTS: By intersecting 102 compound target genes with 6,732 target genes of hypertension, 88 action target genes were obtained, thereby screening out the key compounds and key targets. The results of GO enrichment showed the main molecular functions, biological processes, and cellular components. The main pathways of JWSWG in treating hypertension were revealed by KEGG pathway enrichment. CONCLUSIONS: This research clarified the mechanism of JWSWG in the treatment of hypertension systematically, providing new potential ideas and a theoretical foundation for further experimental and clinical research.


Assuntos
Medicamentos de Ervas Chinesas , Hipertensão , Anti-Hipertensivos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Medicina Tradicional Chinesa
15.
Front Psychol ; 12: 643120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335361

RESUMO

Over time, interlanguage studies have shifted from early qualitative to quantitative studies of specific linguistic structures. However, the focus of these studies is usually on one aspect of an interlanguage instead of the whole system. The ideal object of interlanguage research is a second language (L2) learner language system, for only in this way can the entire L2 learning process can be examined. As a self-organizing and self-regulated system, the panorama of interlanguage can be revealed objectively through a complex network approach. In this study, we construct eight interlanguage dependency syntactic networks of varying proficiency levels and modalities, and conduct a quantitative study of respective network parameters. We find that all syntactic networks of Chinese L2 learners (English native speakers) initially present scale-free and small-world properties. Additionally, there is no sudden syntactic emergence in interlanguage with different modalities. This suggests varying regularities in the development of a syntactic network between interlanguage and native language acquisition. Moreover, the first language plays an important role in L2 development. The network parameters (), L, C, ND, and NC can differentiate interlanguage modalities, and five quantitative parameters, , C, ND, γ', and NC, can indicate L2 proficiency.

16.
Commun Biol ; 4(1): 850, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34239035

RESUMO

The retinal pigmented epithelium (RPE) is a monolayer of multifunctional cells located at the back of the eye. High membrane turnover and polarization, including formation of actin-based apical microvilli, are essential for RPE function and retinal health. Herein, we demonstrate an important role for ßA3/A1-crystallin in RPE. ßA3/A1-crystallin deficiency leads to clathrin-mediated epidermal growth factor receptor (EGFR) endocytosis abnormalities and actin network disruption at the apical side that result in RPE polarity disruption and degeneration. We found that ßA3/A1-crystallin binds to phosphatidylinositol transfer protein (PITPß) and that ßA3/A1-crystallin deficiency diminishes phosphatidylinositol 4,5-biphosphate (PI(4,5)P2), thus probably decreasing ezrin phosphorylation, EGFR activation, internalization, and degradation. We propose that ßA3/A1-crystallin acquired its RPE function before evolving as a structural element in the lens, and that in the RPE, it modulates the PI(4,5)P2 pool through PITPß/PLC signaling axis, coordinates EGFR activation, regulates ezrin phosphorylation and ultimately the cell polarity.


Assuntos
Polaridade Celular/fisiologia , Endocitose , Células Epiteliais/metabolismo , Receptores ErbB/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Cadeia A de beta-Cristalina/metabolismo , Animais , Polaridade Celular/genética , Proteínas do Citoesqueleto/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Camundongos Knockout , Fosfatidilinositol 4,5-Difosfato/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Fosforilação , Ligação Proteica , Epitélio Pigmentado da Retina/citologia , Cadeia A de beta-Cristalina/genética
17.
Artigo em Inglês | MEDLINE | ID: mdl-34281060

RESUMO

This study aimed to test the association between peer attachment and aggressive behavior, as well as the mediating effect of regulatory emotional self-efficacy on this relationship. A total of 1171 (582 male, 589 female) Chinese adolescents completed self-reported questionnaires that assessed peer attachment, regulatory emotional self-efficacy, and aggressive behavior. Path analysis showed that the negative association between peer attachment and adolescent aggressive behavior was mediated by self-efficacy in managing negative emotions. However, the mediating effect of self-efficacy in expressing positive emotions was nonsignificant. Moreover, there was no significant difference in the indirect paths mentioned above between male and female respondents. These findings highlight self-efficacy in managing negative emotions as a potential mechanism linking peer attachment to adolescent aggressive behavior.


Assuntos
Comportamento do Adolescente , Autoeficácia , Adolescente , Agressão , China , Emoções , Feminino , Humanos , Masculino , Grupo Associado
18.
Proc Inst Mech Eng H ; : 9544119211028061, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34281449

RESUMO

The tissue engineering technology provides a new way to solve bone defect. Porous scaffolds supply support and adhesion space for cells. Design of pore structure of scaffolds is one of the key points in tissue engineering scaffolds, because the structure affects the performance of scaffolds directly. In this paper, mechanical properties of square porous Ti6Al4V scaffolds are studied. By finite element simulation, it can be found that the support structure in vertical direction assumes main force, so the structure can be optimized through relative density mapping (RDM) method. The modified arch structures can improve bearing effect of structure with the same porosity. The designed structures are obtained by selective laser melting. Results of compressive strength indicate that the compressive strength decreases with the increase of porosity. When the porosity is between 40% and 60%, the error of compressive strength calculated by Gibson-Ashby model is below 8%. Moreover, the optimized structure clears a better bearing effect, and the bearing capacity can be increased by 20%-30% under the same porosity.

19.
Micromachines (Basel) ; 12(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203595

RESUMO

Based on the scanning grating mirror developed by us, this paper presents a method for precise control of the scanning grating mirror and high-speed spectrum data acquisition. In addition, a system circuit of the scanning grating mirror control and a spectrum signal acquisition system were designed and manufactured. The final results of the experiment show that the control system successfully allowed the precise control of the swing of the scanning grating mirror and the acquisition system successfully carried out the high-speed acquisition and transmission of the spectrum and angle data. The spectrum detection range of the NIR spectrometer was 80-2532 nm. The overall resolution of the spectrum was better than 12 nm.

20.
Adv Sci (Weinh) ; 8(16): e2100736, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34114353

RESUMO

Cross-linked polyethylene glycol-based resin (c-PEGR) is constructed by a ring-opening reaction of polyethylene glycol diglycidyl ether (PEGDE) with epoxy groups and polyether amine (PEA) with amino groups. By confining the hydroxyl groups with inferior oxidative stability to the c-PEGR backbone, the oxidation potential of the PEG-based polymer material with reduced reactivity is boosted to 4.36 V. The c-PEGR based gel electrolyte shows excellent flexibility, lithium-ion transport, lithium compatibility, and enhanced oxidation stability, and is successfully applied to a 4.35 V lithium cobaltate (LCO)||lithium (Li) battery system. A quasi-static linear scanning voltammetry (QS-LSV) method is proposed for the first time to accurately measure the oxidation potential and electrochemical stability window of materials with low conductivities such as polymers, which possesses the advantages of high accuracy and short test time. This work provides new insights and research techniques for selecting polymer electrolytes for high-voltage flexible lithium-ion batteries (LIBs).

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