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1.
Med Sci Monit ; 27: e929510, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33828067

RESUMO

The directional differentiation of bone mesenchymal stem cells (BMSCs) is regulated by a variety of transcription factors and intracellular signaling pathways. In the past, it was thought that the directional differentiation of BMSCs was related to transforming growth factors, such as bone morphogenetic protein (BMP) and MAPK pathway. However, in recent years, some scholars have pointed out that the Wnt signaling pathway, which is a necessary complex network of protein interactions for biological growth and development, takes a significant role in this process and plays a major part in regulating the development of osteoblasts by exerting signal transduction into cells. Also, they have proved the Wnt protein therapeutic truly have positive effects on the viability and osteogenic capacity of bone graft. Recent studies have shown that microRNAs (miRNAs) play an important regulatory role in this process. MiRNAs such as miRNA-218, miRNA-335, miRNA-29, microRNA-30 and other miRNAs exert negative or positive effects on some crucial molecules in the Wnt/ß-catenin pathway, which in turn affect bone metabolism and osteopathy. Thus, miRNAs have been suggested as therapeutic targets for some metabolic bone diseases. This article aims to provide an update on the current status of microRNAs that target the Wnt signaling pathway in the regulation of osteogenesis and bone metabolism and includes a discussion of future areas of research, which can be a theoretical basis for bone metabolism-related diseases.

2.
Nano Lett ; 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33797927

RESUMO

Brain injuries are devastating central nervous system diseases, resulting in cognitive, motor, and sensory dysfunctions. However, clinical therapeutic options are still limited for brain injuries, indicating an urgent need to investigate new therapies. Furthermore, the efficient delivery of therapeutics across the blood-brain barrier (BBB) to the brain is a serious problem. In this study, a facile strategy of dual site-selective functionalized (DSSF) poly(ß-amino esters) was developed using bio-orthogonal chemistry for promoting brain nerve regeneration. Fluorescence colocalization studies demonstrated that these proton-sponge DSSF poly(ß-amino esters) targeted mitochondria through electrostatic interactions. More importantly, this delivery system could effectively accumulate in the injured brain sites and accelerate the recovery of the injured brain. Finally, this DSSF poly(ß-amino esters) platform may provide a new methodology for the construction of dual regioselective carriers in protein/peptide delivery and tissue engineering.

3.
Br J Neurosurg ; : 1-7, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33641541

RESUMO

PURPOSE: To investigate the clinical performance, pathological characteristics, treatment and prognosis of salivary gland malignant tumor (SGMT) with skull base metastasis. METHODS: Five SGMT patients with skull base metastasis were retrospectively studied. Major clinical symptoms included headache, facial paralysis, and ear hearing loss. Three patients had previous history of SGMT resection. All patients underwent preoperative computed tomography (CT) and magnetic resonance imaging (MRI). Craniotomy was performed in three patients, and all the five patients underwent radiotherapy and chemotherapy. RESULTS: Two patients were confirmed as having adenocarcinoma, one patient was pathologically confirmed to have squamous cell carcinoma, one patient had ductal carcinoma, and one patient had acinar cell carcinoma. One patient died after 2 years of treatment, and the remaining 4 patients were followed up for 6 ∼ 24 months, suggesting that the tumor size was not enlarged or showed no local recurrence. CONCLUSION: SGMT with skull base metastasis is extremely rare, and due to similar imaging characteristics, it can be easily misdiagnosed as meningioma or schwannoma. Early diagnosis, extent of invasion, surgery and combination of chemotherapy and radiotherapy are the prognostic factors of the disease.

4.
Drug Des Devel Ther ; 15: 843-855, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658766

RESUMO

Purpose: Coronary microembolization (CME) can cause myocardial inflammation, apoptosis and progressive cardiac dysfunction. On the other hand, breviscapine exerts a significant cardioprotective effect in many cardiac diseases although its role and the potential mechanisms in CME remain unclear. Therefore, the present study aimed to ascertain whether pretreatment with breviscapine could improve CME-induced myocardial injury by alleviating myocardial inflammation and apoptosis. The possible underlying mechanisms were also explored. Methods: In this study, 48 Sprague-Dawley (SD) rats were randomly assigned to the CME, CME + breviscapine (CME + BE), CME + breviscapine + LY294002 (CME + BE + LY) and sham groups (12 rats per group). In addition, the CME model was successfully established by injecting 42 µm inert plastic microspheres into the left ventricle of rats. Rats in the CME + BE and CME + BE + LY groups received 40 mg/kg/d of breviscapine for 7 days before inducing CME. Moreover, rats in the CME + BE + LY group were intraperitoneally injected with the phosphoinositide 3-kinase (PI3K) specific inhibitor, LY294002 (10 mg/kg) 30 minutes before CME modeling. 12 h after surgery, the study measured cardiac function, the serum levels of markers of myocardial injury, myocardial inflammation-associated mRNAs and proteins, myocardial apoptosis-associated mRNAs and proteins and conducted myocardial histopathology. Results: The findings demonstrated that pretreatment with breviscapine alleviated myocardial injury following CME by improving cardiac dysfunction, decreasing the serum levels of markers of myocardial injury, reducing the size of myocardial microinfarct and lowering the cardiomyocyte apoptotic index. More importantly, pretreatment with breviscapine resulted to a decrease in the levels of inflammatory and pro-apoptotic mRNAs and proteins in myocardial tissues and there was an increase in the levels of anti-apoptotic mRNAs and proteins. However, these protective effects were eliminated when breviscapine was combined with LY294002. Conclusion: The findings from this study indicated that breviscapine may inhibit myocardial inflammation and apoptosis by regulating the PI3K/protein kinase B (Akt)/glycogen synthase kinase-3ß (GSK-3ß) pathway, thereby ameliorating CME-induced cardiac dysfunction and reducing myocardial injury.

5.
Medicine (Baltimore) ; 100(8): e24311, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33663048

RESUMO

RATIONALE: Necrotizing periodontal diseases (NPDs) are a group of infectious diseases varying in severity, and microorganisms are responsible for these diseases. Currently, the oral microbiota in early disease has been poorly investigated; thus, the causative pathogen and dynamic alteration of the microbiome in NPDs remain unclear. PATIENT CONCERNS: We report a case of a 33-year-old female patient with severe gingival pain and localized necrotizing ulcerative gingival lesions. Conventional therapy was performed, but the necrotizing lesion continued to develop. DIAGNOSES: X-ray examination showed marginal alveolar bone loss in the involved teeth. Histological examination of a biopsy from the gingival lesion showed chronic inflammatory cell infiltration in the tissue, and no cancer cells were observed. Subgingival swabs were taken from the ulcerative gingiva and the gingiva that was not yet affected, and the composition of the microbiota was analyzed by targeted pyrosequencing of the V3-V4 hypervariable regions of the small subunit ribosomal RNA. We found that Neisseria spp., Corynebacterium spp., and Prevotella spp. were clearly enriched in the lesion site. However, Fusobacteria was more abundant in the not-yet-affected gingiva, and Leptotrichia spp. were the most abundant phylotype. INTERVENTIONS: After clinical assessment, a tooth with poor prognosis was extracted, and minocycline hydrochloride was locally administered in the involved tooth pocket every day. Additionally, the patient received 100 mg of hydrochloric acid doxycycline twice per day. OUTCOMES: Remarkable improvement was obtained after 3 days, and the lesion completely healed after 1 week. The follow-up examination 1 year later showed a complete recovery with no recurrent episodes of pain. LESSONS: Changes in the subgingival microbiome can occurr before clinical symptoms appears, and Fusobacteria may be involved in the imbalance of the subgingival flora in the early stage of NPDs. Moreover, Neisseria is a potential bacterial candidate that deserves further study.


Assuntos
Periodontite Crônica/microbiologia , Periodontite Crônica/patologia , Microbiota/fisiologia , Adulto , Perda do Osso Alveolar , Antibacterianos/uso terapêutico , Periodontite Crônica/tratamento farmacológico , Periodontite Crônica/cirurgia , Feminino , Humanos , Necrose
6.
J Hazard Mater ; 415: 125638, 2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33756194

RESUMO

Deoxynivalenol (DON) is considered a mycotoxin that is toxic to the agricultural environment and human body. It is necessary to study the pathophysiological mechanism of DON toxicity at the cellular level. Cytochrome c (Cyt c), as an important biomarker of DON-induced apoptosis that may lead to a bipartite 'point-of-no return' event, is of great significance to be detected using cell imaging. Herein, we synthesized a DON-deactivated emission fluorescent probe, the molecularly imprinted polymer-coated quantum dots (CdTe@MIP), for monitoring the Cyt c level with a photoinduced electron transfer strategy. The CdTe@MIP probe can be easily loaded into cells and perform well due to its great sensitivity and selectivity and its fluorescence was gradually quenched with the increasing concentration (0-10 µM) and incubation time (0-7.5 h) of DON. Cell imaging results of apoptosis induced by DON was consistent with that of the cell counting kit-8 assay and flow cytometry technique. The developed method can be used to monitor DON-induced apoptosis and provide an early-warning system for the contaminant toxicity.

7.
Chin Med J (Engl) ; 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33734138

RESUMO

BACKGROUND: Recent cardiovascular outcome trials (CVOTs) changed the therapeutic strategy of guidelines for type 2 diabetes. We compared the characteristics of patients from real-world hospital settings with those of participants in recent pragmatic randomized trials. METHODS: This electronic medical record (EMR)-based retrospective observational study investigated the data of patients with diabetes from inpatient and outpatient settings in West China Hospital of Sichuan University from January 1, 2011, to June 30, 2019. We identified patients meeting the inclusion criteria of a pragmatic randomized trial (EMPA-REG OUTCOME) based on EMRs and compared their baseline characteristics with those of the trial participants. The cutoff for the clinical significance of each characteristic was set as its minimal clinically important difference based on expert consultation. RESULTS: We included 48,257 inpatients and 36,857 outpatients with diabetes and found that 8389 (17.4%) inpatients and 2646 (7.2%) outpatients met the inclusion criteria for the EMPA-REG OUTCOME trial. Compared with the trial population, the real-world inpatients meeting the eligibility criteria of the EMPA-REG OUTCOME had similar age, blood pressure, and lipid profiles but comprised of fewer males, metformin users, anti-hypertensive drug users, and aspirin users, and had a lower body mass index. The group of outpatients meeting the eligibility criteria had fewer males, similar age, fewer metformin users, fewer insulin users, fewer anti-hypertensive drug users, and fewer aspirin users compared with the trial population. CONCLUSIONS: The trial population in EMPA-REG OUTCOME represents only a small portion of patients with diabetes from the inpatient and outpatient departments of a Chinese tertiary medical center. Evidence localization in different clinical settings and validation are essential to enabling extrapolation of the results from CVOTs in patients with diabetes to Chinese clinical practice.

8.
J Phys Chem Lett ; : 1657-1663, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33555878

RESUMO

Although the amorphous two-dimensional electron gas (a-2DEG) of oxides provides new opportunities to explore nanoelectronic as well as quantum devices, the intrinsic effect of rare earth (Re = La, Pr, Nd, Sm, Gd, and Tm) elements at ReAlO3/SrTiO3 heterointerfaces is still largely unknown and needs to be addressed systematically. Herein, we first propose that the ionization potential of Re elements is a critical factor for the 2DEG fabricated by chemical spin coating. Furthermore, the photoresponsive properties of heterointerfaces are investigated comprehensively with the ionization potential ranging from 35.79 to 41.69 eV. The results show that the sheet resistances significantly increase with increasing the ionization potential, and a resistance upturn phenomenon is observed at TmAlO3/SrTiO3 heterointerfaces, which can be attributed to the weak localization effect theoretically. The most important observation is the dramatic transition from negative (-178.3%, Re = La) to positive (+89.9%, Re = Gd) photoresponse at ReAlO3/SrTiO3 heterointerfaces under the irradiation of 405 nm light at 50 K. More remarkably, a unique recovery behavior of transient-persistent photoconductivity coexistence at low temperatures is discovered at the TmAlO3/SrTiO3 heterointerface. This work reveals an effective approach to tune the transport and photoresponsive properties by changing Re elements and paves the way for the application of all-oxide devices.

9.
World J Microbiol Biotechnol ; 37(3): 45, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33554321

RESUMO

As a significant constituent in biosphere, bacteria have a great influence on human activity. The detection of pathogen bacteria is closely related to the human health. However, the traditional methods for detection of pathogenic bacteria are time-consuming and difficult for quantification, although they are practical and reliable. Therefore, novel strategies for rapid, sensitive, and cost-effective detection are in great demand. Aptamer is a kind of oligonucleotide that selected by repeated screening in vitro or systematic evolution of ligands by exponential enrichment (SELEX) technology. Over the past years, owing to high affinity and specificity of aptamers, a variety of aptamer-based biosensors have been designed and applied for pathogen detection. In this review, we have discussed the recent advances on the applications of aptamer-based biosensors in detection of pathogenic bacteria. In addition, we also point out some problems in current methods and look forward to the further development of aptamer-based biosensors for pathogen detection.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33608991

RESUMO

AIM: To elucidates the mechanism that disulfiram/copper complex (DSF/Cu) treatment activates chloride channels and induces apoptosis in prostate cancer cells. METHODS: Cellular membrane currents were measured by membrane clamp technique; western blot to detect protein expression; flow cytometry to detect apoptosis; immunofluorescence to detect target protein co-localization, and further validated by a combination of protein-protein interaction and mock protein molecular docking techniques. RESULTS: DSF/Cu activated chloride channels and induced apoptosis in LNCaP (a type of androgen-dependent prostate cancer cells) cells. The chloride currents activated by DSF/Cu were significantly reduced after knockdown of CLC3 with siRNA. In addition, DSF/Cu-activated chloride currents were reduced to background current levels after perfusion with genistein, a highly specific tyrosine kinase inhibitor. Conversely, DSF/Cu failed to activate chloride currents in LNCaP cells after 30 minutes of pre-incubation with genistein. When genistein was removed, and DSF/Cu was added, the activated currents were small and unstable, and gradually decreased. Immunofluorescence in LNCaP cells also showed co-localization of the CLC3 protein with tyrosine kinase 2ß (PTK2B). CONCLUSION: DSF/Cu can activate chloride channels and induce apoptosis in LNCaP cells with the involvement of tyrosine kinase. These results provide new insights into the target therapy of prostate cancer.

11.
Sci Adv ; 7(7)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33579710

RESUMO

The gut microbiota fundamentally regulates intestinal homeostasis and disease partially through mechanisms that involve modulation of regulatory T cells (Tregs), yet how the microbiota-Treg cross-talk is physiologically controlled is incompletely defined. Here, we report that prostaglandin E2 (PGE2), a well-known mediator of inflammation, inhibits mucosal Tregs in a manner depending on the gut microbiota. PGE2 through its receptor EP4 diminishes Treg-favorable commensal microbiota. Transfer of the gut microbiota that was modified by PGE2-EP4 signaling modulates mucosal Treg responses and exacerbates intestinal inflammation. Mechanistically, PGE2-modified microbiota regulates intestinal mononuclear phagocytes and type I interferon signaling. Depletion of mononuclear phagocytes or deficiency of type I interferon receptor diminishes PGE2-dependent Treg inhibition. Together, our findings provide emergent evidence that PGE2-mediated disruption of microbiota-Treg communication fosters intestinal inflammation.

12.
Biomed Res Int ; 2021: 4192451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33506015

RESUMO

Methods: Colitis was induced in mice using 2,4,6-trinitrobenzene-sulfonic acid (TNBS), and mice were subsequently treated with either a PD-1 inhibitor or 5-amino-salicylic acid (ASA) as a positive control. Body weight, disease activity index (DAI), colon length, and tissue damage were evaluated, and the enteric microbiota was profiled using high-throughput 16S rRNA sequencing of fecal samples from the experimental mice. Results: TNBS caused mice to experience IBD-like symptoms, which were attenuated by the PD-1 inhibitor, as indicated by a decrease in DAI scores (p = 0.0002). Furthermore, in this mouse model of IBD, PD-1 inhibition improved the alpha diversity as well as restored the beta diversity of the enteric microbiome. It also significantly enriched the abundance of short-chain fatty acid- (SCFA-) producing bacteria of the Firmicutes (p < 0.05) and Bacteroidetes (p < 0.05) phyla but depopulated Proteobacteria (p < 0.05). Conclusion: PD-1 inhibition can partly mitigate TNBS-induced colitis and restore the enteric microbiota by enriching the abundance of SCFA-producing bacteria.

13.
Appl Microbiol Biotechnol ; 105(4): 1669-1681, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33511441

RESUMO

The gut microbiota is closely related to host health and disease. However, there are no suitable animal models available at present for exploring its functions. We analyzed the effect of 3 different antibiotic cocktails (ABx) via two administration routes on the composition of murine gut microbiota, as well as on the general physiological and metabolic indices. High-throughput 16S rRNA sequencing showed that ABx treatment altered the gut microbiota community structure, and also caused low-degree inflammation in the colon. In addition, ad libitum administration of antibiotics depleted the gut microbiota more effectively compared to direct oral gavage, especially with 3ABx. The ABx treatment also had a significant impact on renal and liver functions, as indicated by the altered serum levels of creatinine, urea, total triglycerides, and total cholesterol. Finally, Spearman's correlation analysis showed that the predominant bacterial genera resulting from ABx intervention, including Lactobacillus, Roseburia, and Candidatus-Saccharimonas, were negatively correlated with renal function indices. Taken together, different antibiotic combinations and interventions deplete the gut microbiota and induce physiological changes in the host. Our findings provide the basis for developing an adaptive animal model for studying gut microbiota. KEY POINTS: • Ad libitum administration of 3ABx can effectively deplete intestinal microbiota. • ABx treatment may have slight effect on renal and liver function. • The levels of urea and creatinine correlated with the growth of Roseburia.

14.
Cancer Cell ; 39(2): 257-275.e6, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33476581

RESUMO

Given the immune system's importance for cancer surveillance and treatment, we have investigated how it may be affected by SARS-CoV-2 infection of cancer patients. Across some heterogeneity in tumor type, stage, and treatment, virus-exposed solid cancer patients display a dominant impact of SARS-CoV-2, apparent from the resemblance of their immune signatures to those for COVID-19+ non-cancer patients. This is not the case for hematological malignancies, with virus-exposed patients collectively displaying heterogeneous humoral responses, an exhausted T cell phenotype and a high prevalence of prolonged virus shedding. Furthermore, while recovered solid cancer patients' immunophenotypes resemble those of non-virus-exposed cancer patients, recovered hematological cancer patients display distinct, lingering immunological legacies. Thus, while solid cancer patients, including those with advanced disease, seem no more at risk of SARS-CoV-2-associated immune dysregulation than the general population, hematological cancer patients show complex immunological consequences of SARS-CoV-2 exposure that might usefully inform their care.


Assuntos
/imunologia , Neoplasias/imunologia , Neoplasias/virologia , Síndrome Respiratória Aguda Grave/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , /mortalidade , Feminino , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/virologia , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Neoplasias/mortalidade , Neoplasias/terapia , Síndrome Respiratória Aguda Grave/etiologia , Síndrome Respiratória Aguda Grave/mortalidade , Síndrome Respiratória Aguda Grave/virologia , Linfócitos T/virologia , Eliminação de Partículas Virais , Adulto Jovem
15.
Sci Rep ; 11(1): 2037, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479390

RESUMO

Transverse-tubules (T-tubules) play pivotal roles in Ca2+-induced, Ca2+ release and excitation-contraction coupling in cardiomyocytes. The purpose of this study was to uncover mechanisms where sarco/endoplasmic reticulum Ca2+ ATPase (SERCA2a) improved cardiac function through T-tubule regulation during myocardial ischemia/reperfusion (I/R). SERCA2a protein expression, cytoplasmic [Ca2+]i, calpain activity, junctophilin-2 (JPH2) protein expression and intracellular localization, cardiomyocyte T-tubules, contractility and calcium transients in single cardiomyocytes and in vivo cardiac functions were all examined after SERCA2a knockout and overexpression, and Calpain inhibitor PD150606 (PD) pretreatment, following myocardial I/R. This comprehensive approach was adopted to clarify SERCA2a mechanisms in improving cardiac function in mice. Calpain was activated during myocardial I/R, and led to the proteolytic cleavage of JPH2. This altered the T-tubule network, the contraction function/calcium transients in cardiomyocytes and in vivo cardiac functions. During myocardial I/R, PD pretreatment upregulated JPH2 expression and restored it to its intracellular location, repaired the T-tubule network, and contraction function/calcium transients of cardiomyocytes and cardiac functions in vivo. SERCA2a suppressed calpain activity via [Ca2+]i, and ameliorated these key indices. Our results suggest that SERCA2a ameliorates cardiomyocyte T-tubule remodeling via the calpain/JPH2 pathway, thereby improving cardiac function in myocardial I/R mice.

16.
Stem Cell Res Ther ; 12(1): 64, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33461605

RESUMO

BACKGROUND: Human adipose-derived stem cells (hADSCs) are stem cells with the potential to differentiate in multiple directions. miR-204-5p is expressed at low levels during the osteogenic differentiation of hADSCs, and its specific regulatory mechanism remains unclear. Here, we aimed to explore the function and possible molecular mechanism of miR-204-5p in the osteogenic differentiation of hADSCs. METHODS: The expression patterns of miR-204-5p, Runx2, alkaline phosphatase (ALP), osteocalcin (OCN), forkhead box C1 (FOXC1) and growth differentiation factor 7 (GDF7) in hADSCs during osteogenesis were detected by qRT-PCR. Then, ALP and alizarin red staining (ARS) were used to detect osteoblast activities and mineral deposition. Western blotting was conducted to confirm the protein levels. The regulatory relationship among miR-204-5p, FOXC1 and GDF7 was verified by dual-luciferase activity and chromatin immunoprecipitation (ChIP) assays. RESULTS: miR-204-5p expression was downregulated in hADSC osteogenesis, and overexpression of miR-204-5p suppressed osteogenic differentiation. Furthermore, the levels of FOXC1 and GDF7 were decreased in the miR-204-5p mimics group, which indicates that miR-204-5p overexpression suppresses the expression of FOXC1 and GDF7 by binding to their 3'-untranslated regions (UTRs). Overexpression of FOXC1 or GDF7 improved the inhibition of osteogenic differentiation of hADSCs induced by the miR-204-5p mimics. Moreover, FOXC1 was found to bind to the promoter of miR-204-5p and GDF7, promote the deacetylation of miR-204-5p and reduce the expression of miR-204-5p, thus promoting the expression of GDF7 during osteogenic differentiation. GDF7 induced hADSC osteogenesis differentiation by activating the AKT and P38 signalling pathways. CONCLUSIONS: Our results demonstrated that the miR-204-5p/FOXC1/GDF7 axis regulates the osteogenic differentiation of hADSCs via the AKT and p38 signalling pathways. This study further revealed the regulatory mechanism of hADSC differentiation from the perspective of miRNA regulation.

17.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477511

RESUMO

Considering the complexity of the physical model of wildfire occurrence, this paper develops a method to evaluate the wildfire risk of transmission-line corridors based on Naïve Bayes Network (NBN). First, the data of 14 wildfire-related factors including anthropogenic, physiographic, and meteorologic factors, were collected and analyzed. Then, the relief algorithm is used to rank the importance of factors according to their impacts on wildfire occurrence. After eliminating the least important factors in turn, an optimal wildfire risk assessment model for transmission-line corridors was constructed based on the NBN. Finally, this model was carried out and visualized in Guangxi province in southern China. Then a cost function was proposed to further verify the applicability of the wildfire risk distribution map. The fire events monitored by satellites during the first season in 2020 shows that 81.8% of fires fall in high- and very-high-risk regions.

18.
Nat Mater ; 20(4): 480-487, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33398121

RESUMO

Moiré superlattices in twisted van der Waals materials have recently emerged as a promising platform for engineering electronic and optical properties. A major obstacle to fully understanding these systems and harnessing their potential is the limited ability to correlate direct imaging of the moiré structure with optical and electronic properties. Here we develop a secondary electron microscope technique to directly image stacking domains in fully functional van der Waals heterostructure devices. After demonstrating the imaging of AB/BA and ABA/ABC domains in multilayer graphene, we employ this technique to investigate reconstructed moiré patterns in twisted WSe2/WSe2 bilayers and directly correlate the increasing moiré periodicity with the emergence of two distinct exciton species in photoluminescence measurements. These states can be tuned individually through electrostatic gating and feature different valley coherence properties. We attribute our observations to the formation of an array of two intralayer exciton species that reside in alternating locations in the superlattice, and open up new avenues to realize tunable exciton arrays in twisted van der Waals heterostructures, with applications in quantum optoelectronics and explorations of novel many-body systems.

19.
J Psycholinguist Res ; 50(1): 51-64, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33511546

RESUMO

Reflecting/Reorganizing (R/R) is one of the three functions described by Bucci (Overview of the referential process: the operation of language within and between people, 2021a) as part of the referential process. The Weighted Referential Activity Dictionary (WRAD) was previously developed to model the Symbolizing function of the referential process. This paper presents the development of the Weighted Reflecting Reorganizing List (WRRL) as a model of the R/R function. The basic premise of this approach is that by rating segments of text rather than individual words, and using a word by word weighting procedure designed for this purpose, it is possible to identify the nature of the language style that is connected with particular degrees of involvement in the psychological process being modeled. Starting with a brief description of the R/R function, an iterative process was applied that resulted in a clear scoring manual for the R/R function. The method of developing the dictionary is described, a study providing validation for the measure is presented, and the nature of the language style used to express the R/R function is discussed. As was described for the WRAD, the language style of the WRRL was found to involve use of particular function words, applicable across a wide range of contents.

20.
Cell Death Dis ; 12(1): 78, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436548

RESUMO

Coronary microembolization (CME), a common reason for periprocedural myocardial infarction (PMI), bears very important prognostic implications. However, the molecular mechanisms related to CME remain largely elusive. Statins have been shown to prevent PMI, but the underlying mechanism has not been identified. Here, we examine whether the NLRP3 inflammasome contributes to CME-induced cardiac injury and investigate the effects of statin therapy on CME. In vivo study, mice with CME were treated with 40 mg/kg/d rosuvastatin (RVS) orally or a selective NLRP3 inflammasome inhibitor MCC950 intraperitoneally (20 mg/kg/d). Mice treated with MCC950 and RVS showed improved cardiac contractile function and morphological changes, diminished fibrosis and microinfarct size, and reduced serum lactate dehydrogenase (LDH) level. Mechanistically, RVS decreased the expression of NLRP3, caspase-1, interleukin-1ß, and Gasdermin D N-terminal domains. Proteomics analysis revealed that RVS restored the energy metabolism and oxidative phosphorylation in CME. Furthermore, reduced reactive oxygen species (ROS) level and alleviated mitochondrial damage were observed in RVS-treated mice. In vitro study, RVS inhibited the activation of NLRP3 inflammasome induced by tumor necrosis factor α plus hypoxia in H9c2 cells. Meanwhile, the pyroptosis was also suppressed by RVS, indicated by the increased cell viability, decreased LDH and propidium iodide uptake in H9c2 cells. RVS also reduced the level of mitochondrial ROS generation in vitro. Our results indicate the NLRP3 inflammasome-dependent cardiac pyroptosis plays an important role in CME-induced cardiac injury and its inhibitor exerts cardioprotective effect following CME. We also uncover the anti-pyroptosis role of RVS in CME, which is associated with regulating mitochondrial ROS.

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