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1.
Inflammation ; 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757554

RESUMO

Neuropathic pain (NP) treatment remains a challenge because the pathomechanism is not yet fully understood. Because of low treatment efficacy, there is an important unmet need in neuropathic pain patients, and the development of a more effective pharmacotherapy is urgently required. Neuroinflammation induced by oxidative stress-mediated activation of nuclear factor-kappa B (NF-κB) plays an important role in NP. In this study, we aimed to investigate the protective properties of tetrahydropalmatine (THP) on a spared nerve injury (SNI) model of neuropathic pain in mice in in vivo and also in in vitro experiments. THP decreased mechanical hyperalgesia and cold allodynia compared with the SNI group. A microarray was applied to analyze differentially expressed of mRNA among different groups, and THP noticeably changed the expression of MAPK-related proteins compared with the SNI groups. H&E staining showed that the THP changed the inflammation after the spared nerve injury, with decreased NO expression in the THP group as compared to the SNI group. In addition, SNI-induced pain was reversed by intraperitoneal administration of THP, and further results indicated that THP suppressed inducible nitric oxide synthase (iNOS, pro-nociceptive mediators), phosphorylated MAPKs, and p65 in the dorsal root ganglions and sciatic nerve, while the serum levels of the pro-inflammatory cytokines IL-1ß were significantly higher in the SNI group as compared to the THP group. To identify the molecular mechanism of the antineuropathic activity of THP, sodium nitroprusside (SNP)-induced neuro-2a (N2a) cells, LPS-induced BV2 cells, and LTA-induced astrocytes were further investigated in signaling pathways. In vitro experiments indicated that THP suppressed the expression of IL-1ß, iNOS, phosphorylated MAPKs, and p65, which were assayed using western blotting, and immunofluorescence.

2.
J Stroke Cerebrovasc Dis ; 31(1): 106202, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775182

RESUMO

OBJECTIVE: Electroacupuncture (EA) pretreatment has been shown to alleviate cerebral ischemia-reperfusion (I/R) injury; however, the underlying mechanism remains unclear. To investigate the involvement of mTOR signaling in the protective role of EA in I/R-induced brain damage and mitochondrial injury. METHODS: Sprague-Dawley male rats were pretreated with vehicle, EA (at Baihui and Shuigou acupoints), or rapamycin + EA for 30 min daily for 5 consecutive days, followed by the middle cerebral artery occlusion to induce I/R injury. The neurological functions of the rats were assessed using the Longa neurological deficit scores. The rats were sacrificed immediately after neurological function assessment. The brains were obtained for the measurements of cerebral infarct area. The mitochondrial structural alterations were observed under transmission electron microscopy. The mitochondrial membrane potential changes were detected by JC-1 staining. The alterations in autophagy-related protein expression were examined using Western blot analysis. RESULTS: Compared with untreated I/R rats, EA-pretreated rats exhibited significantly decreased neurological deficit scores and cerebral infarct volumes. EA pretreatment also reversed I/R-induced mitochondrial structural abnormalities and loss of mitochondrial membrane potential. Furthermore, EA pretreatment downregulated the protein expression of LC3-II, p-ULK1, and FUNDC1 while upregulating the protein expression of p-mTORC1 and LC3-I. Rapamycin effectively blocked the above-mentioned effects of EA. CONCLUSION: EA pretreatment at Baihui and Shuigou alleviates cerebral I/R injury and mitochondrial impairment in rats through activating the mTORC1 signaling. The suppression of autophagy-related p-ULK1/FUNDC1 pathway is involved in the neuroprotective effects of EA.

3.
J Control Release ; 341: 147-165, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34813880

RESUMO

Fabricating injectable hydrogel with multifunctions that matchs the highly ordered healing process of skin regeneration has greatly desired in treatment of chronic diabetic wounds. Herein, a pH/reactive oxygen species (ROS) dual responsive injectable glycopeptide hydrogel based on phenylboronic acid-grafted oxidized dextran and caffeic acid-grafted ε-polylysine was constructed, which exhibited inherent antibacterial and antioxidant capacities. The mangiferin (MF) with the ability to promote angiogenesis was encapsulated into pH-responsive micelles (MIC). Subsequently, diclofenac sodium (DS) with anti-inflammatory activities and MIC@MF were embedded into the hydrogel. The hydrogel possessed good biodegradability, stable rheological property and self-healing ability, and could realize the spatiotemporal delivery of DS and MF. The in vitro and in vivo data showed that the hydrogel was biocompatible with effective anti-infection, anti-oxidation and anti-inflammation at early stages, then further promoted angiogenesis and accelerated wound repairing. Collectively, this novel glycopeptide hydrogel provides a facile and effective strategy for chronic diabetic wound repairing.

4.
J Mater Chem B ; 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821252

RESUMO

Recently, the incidence of chronic diabetic wounds increases continuously, and the existing clinical treatment is less effective. Thus, it is an urgent need to solve these problems for better clinical treatment effects. Herein, we prepared a brand-new tailored recombinant human collagen type III (rhCol III) and constructed a multifunctional microenvironment-responsive hydrogel carrier based on multifunctional antibacterial nanoparticles (PDA@Ag NPs) and our tailored rhCol III. The multifunctional smart hydrogel disintegrated quickly at the chronic diabetic wound sites and achieved the programed on-demand release of different therapeutic substances. The first released PDA@Ag NPs showed great antibacterial properties against S. aureus and E. coli. They could kill bacteria rapidly, and also showed antioxidant and anti-inflammatory effects at the wound site. The subsequent release of our tailored rhCol III could promote the proliferation and migration of mouse fibroblasts and endothelial cells during the proliferation and remodeling process of wound healing. Relevant results showed that the multifunctional smart hydrogel could promote the expression levels of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), decrease the inflammatory response, accelerate the deposition of collagen and increase cell proliferation and angiogenesis, thereby speeding up the healing of infected chronic wounds. In a word, the hydrogel, which took into consideration the complex microenvironment at the wound site and multi-stage healing process, could achieve programmed and responsive release of different therapeutic substances to meet the treatment needs in different wound healing stages. More importantly, our work illustrated the great application potential of our brand-new rhCol III in promoting chronic wound repair and regeneration.

5.
Zhongguo Gu Shang ; 34(10): 947-52, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34726024

RESUMO

OBJECTIVE: To investigate the clinical effect of vancomycin bone cement in the treatment of diabetic foot ulcer (DFU) ruptured Wagner gradeⅡ-Ⅳ. METHODS: From March 2019 to April 2021, 32 patients with Wagner gradeⅡ-Ⅳ diabetic foot were divided into vacuum sealing drainage (VSD) group and bone cement group according to different treatment methods. There were 16 cases in VSD group, 8 males and 8 females;the age ranged from 66 to 81 (70.50±7.20) years, and the course of disease ranged from 8 to 40 (27.56±8.55) months;Wagner gradeⅡin 2 cases, grade Ⅲin 7 cases and grade Ⅳin 7 cases;debridement and VSD were used. There were 16 cases in the bone cement group, 9 males and 7 females;the age ranged from 63 to 79 (69.56±7.29) years, and the course of disease ranged from 11 to 39(22.75±11.43) months;Wagner gradeⅡ in 2 cases, grade Ⅲin 5 cases and grade Ⅳ in 9 cases;vancomycin loaded bone cement was used for treatment. The types of bacteria, negative time of bacterial culture, skin healing time, hospital stay, operation times and complications were observed and compared between two groups. RESULTS: All patients were followed up for 3 to 6 (4.00±1.07) months. The bacterial negative time, skin healing time and hospital stay in bone cement group were significantly lower than those in VSD group (P<0.05). The median number of operations in both groups was 2, and there was no significant difference (P>0.05). According to the analysis of pathogens in two groups, there were 13 cases of G+ patients, 14 cases of G- patients and 5 cases of mixed bacteria. The number of G+, G- and mixed bacteria in bone cement group was 6, 7 and 3 cases respectively, and the number of G+, G- and mixed bacteria in VSD group was 7, 7 and 2 cases respectively. The wounds of 32 patientsin two groups healed completely without complications. CONCLUSION: Vancomycin loaded bone cement is effective in the treatment of Wagner grade Ⅱ-Ⅳ diabetic foot ulceration wounds. It can reduce the length of hospital stay, shorten the healing time of skin and kill pathogens as soon as possible. It is one of the effective methods to treat Wagner gradeⅡ-Ⅳdiabetic foot ulceration.


Assuntos
Diabetes Mellitus , Pé Diabético , Cimentos Ósseos/uso terapêutico , Criança , Pré-Escolar , Pé Diabético/tratamento farmacológico , Feminino , Humanos , Masculino , Resultado do Tratamento , Vancomicina , Cicatrização
6.
Acta Pharmacol Sin ; 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737421

RESUMO

Acute lung injury (ALI) is a sudden onset systemic inflammatory response. ALI causes severe morbidity and death and currently no effective pharmacological therapies exist. Natural products represent an excellent resource for discovering new drugs. Screening anti-inflammatory compounds from the natural product bank may offer viable candidates for molecular-based therapies for ALI. In this study, 165 natural compounds were screened for anti-inflammatory activity in lipopolysaccharide (LPS)-challenged macrophages. Among the screened compounds, flavokawain B (FKB) significantly reduced LPS-induced pro-inflammatory IL-6 secretion in macrophages. FKB also reduced the formation of LPS/TLR4/MD2 complex by competitively binding to MD2, suppressing downstream MAPK and NF-κB signaling activation. Finally, FKB treatment of mice reduced LPS-induced lung injury, systemic and local inflammatory cytokine production, and macrophage infiltration in lungs. These protective activities manifested as increased survival in the ALI model, and reduced mortality upon bacterial infection. In summary, we demonstrate that the natural product FKB protects against LPS-induced lung injury and sepsis by interacting with MD2 and inhibiting inflammatory responses. FKB may potentially serve as a therapeutic option for the treatment of ALI.

7.
Small ; : e2105687, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34837309

RESUMO

Electrostatic gating lies in the heart of field effect transistor (FET) devices and modern integrated circuits. To achieve efficient gate tunability, the gate electrode has to be placed very close to the conduction channel, typically a few nanometers. Remote control of a FET device through a gate electrode located far away is highly desirable, because it not only reduces the complexity of device fabrication, but also enables the design of novel devices with new functionalities. Here, a non-local electrostatic gating effect in graphene devices using scanning near-field optical microscopy (SNOM)-a technique that can probe local charge density in graphene-is reported. Remarkably, the charge density of the graphene region tens of micrometers away from a local gate can be efficiently tuned. The observed non-local gating effect is initially driven by an in-plane electric field induced by the quantum capacitance of graphene, and further largely enhanced by adsorbed polarized water molecules. This study reveals a non-local phenomenon of Dirac electrons, provides a deep understanding of in-plane screening from Dirac electrons, and paves the way for designing novel electronic devices with remote gate control.

8.
Chemistry ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34791726

RESUMO

Rapid capture of 129 I with high volatility and toxicity in the environment has attracted much attention. Herein we reported a firstly synthesized nonporous material: pyridine N-oxides (NTPO and ATPO) as iodine adsorbent. Both of NTPO and ATPO exhibit remarkable performance on the adsorption of iodine in aqueous solution, vapor state and organic solvents. Upon the capture of iodine, pyridine N-oxides were transformed to binary cocrystals combined with the pyridine N-oxides and iodine which is driven by halogen bond between iodine and oxygen atoms. Moreover, pyridine N-oxides shows high chemical, thermal and moisture stability.

9.
Oxid Med Cell Longev ; 2021: 5838101, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777689

RESUMO

Luteolin (LUT) possesses multiple biologic functions and has beneficial effects for cardiovascular and cerebral vascular diseases. Here, we investigated the protective effects of LUT against subarachnoid hemorrhage (SAH) and the involvement of underlying molecular mechanisms. In a rat model of SAH, LUT significantly inhibited SAH-induced neuroinflammation as evidenced by reduced microglia activation, decreased neutrophil infiltration, and suppressed proinflammatory cytokine release. In addition, LUT markedly ameliorated SAH-induced oxidative damage and restored the endogenous antioxidant systems. Concomitant with the suppressed oxidative stress and neuroinflammation, LUT significantly improved neurologic function and reduced neuronal cell death after SAH. Mechanistically, LUT treatment significantly enhanced the expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), while it downregulated nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation. Inhibition of Nrf2 by ML385 dramatically abrogated LUT-induced Nrf2 activation and NLRP3 suppression and reversed the beneficial effects of LUT against SAH. In neurons and microglia coculture system, LUT also mitigated oxidative stress, inflammatory response, and neuronal degeneration. These beneficial effects were associated with activation of the Nrf2 and inhibitory effects on NLRP3 inflammasome and were reversed by ML385 treatment. Taken together, this present study reveals that LUT confers protection against SAH by inhibiting NLRP3 inflammasome signaling pathway, which may be modulated by Nrf2 activation.

10.
World J Surg Oncol ; 19(1): 294, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600547

RESUMO

BACKGROUND: Breast cancer (BC) has a high incidence and mortality rate in females. Its conventional clinical characteristics are far from accurate for the prediction of individual outcomes. Therefore, we aimed to develop a novel signature to predict the survival of patients with BC. METHODS: We analyzed the data of a training cohort from the Cancer Genome Atlas (TCGA) database and a validation cohort from the Gene Expression Omnibus (GEO) database. After the applications of Gene Set Enrichment Analysis (GSEA) and Cox regression analyses, a glycolysis-related signature for predicting the survival of patients with BC was developed; the signature contained AK3, CACNA1H, IL13RA1, NUP43, PGK1, and SDC1. Furthermore, on the basis of expression levels of the six-gene signature, we constructed a risk score formula to classify the patients into high- and low-risk groups. The receiver operating characteristic (ROC) curve and the Kaplan-Meier curve were used to assess the predicted capacity of the model. Later, a nomogram was developed to predict the outcomes of patients with risk score and clinical features over a period of 1, 3, and 5 years. We further used Human Protein Atlas (HPA) database to validate the expressions of the six biomarkers in tumor and sample tissues, which were taken as control. RESULTS: We constructed a six-gene signature to predict the outcomes of patients with BC. The patients in the high-risk group showed poor prognosis than those in the low-risk group. The area under the curve (AUC) values were 0.719 and 0.702, showing that the prediction performance of the signature is acceptable. Additionally, Cox regression analysis revealed that these biomarkers could independently predict the prognosis of BC patients with BC without being affected by clinical factors. The expression levels of all six biomarkers in BC tissues were higher than that in normal tissues; however, AK3 was an exception. CONCLUSION: We developed a six-gene signature to predict the prognosis of patients with BC. Our signature has been proved to have the ability to make an accurate prediction and might be useful in expanding the hypothesis in clinical research.


Assuntos
Neoplasias da Mama , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , Estimativa de Kaplan-Meier , Prognóstico
11.
Ann Palliat Med ; 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34670386

RESUMO

BACKGROUND: At present, some cancer patients experience hyperprogressive disease (HPD) after receiving immunotherapy. This study used the Response Evaluation Criteria in Solid Tumors 1.1 to evaluate the incidence of HPD in patients receiving immune checkpoint inhibitors (ICIs) for treating primary liver cancer (PLC) and to explore the risk factors for HPD. METHODS: This retrospective, single-center study included patients with PLC who were treated with ICIs. The RECIST 1.1 was used to determine patients with HPD. Univariate and multivariate regression analyses were performed to explore the risk factors for HPD, and clinical variables with prognostic significance for HPD were included to establish a risk model. RESULTS: Among 129 patients with PLC treated with ICIs, HPD occurred in 13 patients (10.1%). In the multivariate regression analysis, lymph node metastasis and lung metastasis were risk factors for HPD. The area under the curve of the risk model, established by including lymph node metastasis, lung metastasis, neutrophil-lymphocyte ratio, albumin, and performance status, was 0.801 (P<0.001). The progression-free survival of HPD patients was significantly worse than that of non-HPD patients (P<0.001). CONCLUSIONS: In this study, 10.1% of patients with PLC had HPD. Compared with the non-HPD patients, lung metastasis and lymph node metastasis were independent risk factors of HPD.

12.
Opt Express ; 29(18): 28124-28133, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34614951

RESUMO

Optical underwater target imaging and detection have been a tough but significant challenge in deep-sea exploration. Distant reflected signals drown in various underwater noises due to strong absorption and scattering, resulting in degraded image contrast and reduced detection range. Single-photon feature operating at the fundamental limit of the classical electromagnetic waves can broaden the realm of quantum technologies. Here we experimentally demonstrate a thresholded single-photon imaging and detection scheme to extract photon signals from the noisy underwater environment. We reconstruct the images obtained in a high-loss underwater environment by using photon-limited computational algorithms. Furthermore, we achieve a capability of underwater detection down to 0.8 photons per pulse at Jerlov type III water up to 50 meters, which is equivalent to more than 9 attenuation lengths. The results break the limits of classical underwater imaging and detection and may lead to many quantum-enhanced applications, like air-to-sea target tracking and deep-sea optical exploration.

13.
Clin Appl Thromb Hemost ; 27: 10760296211040109, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34617462

RESUMO

Objective: We tried to find the relationship between statin and diabetes retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM). Methods: We searched the databases of PubMed, EMBASE, and the Cochrane Library for eligible studies reporting on the relationships between statin use and DR, from inception to September 25, 2020. The terms searched including Diabetes Mellitus, Type 2, Hydroxymethylglutaryl-CoA Reductase Inhibitors, and Diabetic Retinopathy. We expressed the results as the odds ratios (ORs) with 95% confidence intervals (CIs) which were calculated using a random-effects model. Results: A total of 6 eligible studies, including 43 826 patients, were included in the meta-analysis. The meta-analysis showed that statin was not associated with elevated risk of DR [OR = 0.96 (95% CI: 0.80-1.16), P = .68]. Similarly, no differences were found between statin and placebo in participants ≥500 [OR = 0.98 (95% CI: 0.80-1.21)] or participants <500 [OR = 0.90 (95% CI: 0.49-1.66)]. Further, we conducted a meta-analysis to study the effect of statin therapy on DR in people with type 2 diabetes according to age and found that statin use was associated with a decreased risk of DR in patients with type 2 diabetes 40 years of age or older [OR = 0.87 (95% CI: 0.82-0.92)]. Conclusion: Our meta-analysis revealed that statin was not associated with elevated risk of DR in patients with T2DM. Moreover, statin use was associated with a lower incidence of DR in patients with type 2 diabetes 40 years of age or older.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34709801

RESUMO

Most chronic wounds suffer from infections, and their treatment is challenging. The usage of antibiotics may lead to bacterial resistance and adverse side effects. Positively charged substances have shown promise, but their applications are usually limited by certain cytotoxicity or complex synthesis. Doped polyaniline that carries a high density of positive charges would be a promising candidate due to its good biocompatibility and easy availability, but its interaction with bacteria has not been elucidated. Herein, the distinct bactericidal effect of polyaniline against Gram-positive bacteria has been verified. The antibacterial activity may result from the specific interaction with lipoteichoic acid to destroy the Gram-positive bacterial cell wall. Polyaniline and a macromolecular dopant (sulfonated hyaluronic acid) are used to construct a flexible hydrogel with skin-mimic electrical conductivity. The in vivo results demonstrate that electrical stimulation (ES) through this hydrogel is superior to ES via separated electrodes (the ES strategy used clinically) for promoting infected chronic wound healing.

15.
Diabetes ; 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675006

RESUMO

The mechanisms underlying the pathogenesis of steatosis and insulin resistance in nonalcoholic fatty liver disease remain elusive. Increased phosphorylation of hepatic p38 has long been noticed in fatty liver; however, whether the activation of hepatic p38 is a cause or consequence of liver steatosis is unclear. Here, we demonstrate that hepatic p38 activation by MKK6 overexpression in the liver of mice induces severe liver steatosis, reduces fat mass, and elevates circulating fatty acid levels in a hepatic p38α- and FGF21-dependent manner. Mechanistically, through increasing the FGF21 production from liver, hepatic p38 activation increases the influx of fatty acids from adipose tissue to liver, leading to hepatic ectopic lipid accumulation and insulin resistance. Although hepatic p38 activation exhibits favorable effects in peripheral tissues, it impairs the hepatic FGF21 action by facilitating the ubiquitination and degradation of FGF21 receptor cofactor ß-Klotho. Consistently, we show that p38 phosphorylation and FGF21 expffression are increased, ß-Klotho protein levels are decreased in the fatty liver of either mice or patients. In conclusion, our study reveals previously undescribed effects of hepatic p38 activation on systemic metabolism and provides new insights into the roles of hepatic p38α, FGF21, and ß-Klotho in the pathogenesis of nonalcoholic fatty liver disease.

16.
J Diabetes Res ; 2021: 6303063, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660811

RESUMO

This study aimed to evaluate the influence of Jinlida granules on glycemic variability with or without metformin treatment in patients with newly diagnosed type 2 diabetes. This study was a 16-week, double-blinded, randomized, controlled clinical trial. The enrolled patients with newly diagnosed type 2 diabetes were randomly divided into four groups: control, Jinlida, metformin, and combination treatment groups. A retrospective continuous glucose monitoring (CGM) system was used for subcutaneous interstitial glucose monitoring for 3 days consecutively. Hemoglobin A1c (HbA1c), traditional Chinese medicine symptom score, and CGM parameters, including glucose coefficient of variation, standard deviation of blood glucose values, and time in range of glucose 3.9-10.0 mmol/L, were assessed pre-test and post-test. A total of 138 participants completed the entire procedure. Compared with the pre-test, fasting plasma glucose, 2 hour postprandial plasma glucose, HbA1c, and traditional Chinese medicine symptom score all decreased in the four groups at the end of the test, and the combination treatment group showed the most significant decrease. In terms of CGM parameters, time in range of the Jinlida and metformin groups improved after intervention compared with the baseline (Jinlida group: 78.68 ± 26.15 versus 55.47 ± 33.29; metformin group: 87.29 ± 12.21 vs. 75.44 ± 25.42; P < 0.01). Additionally, only the Jinlida group showed decreased glucose standard deviation after intervention (1.57 ± 0.61 vs. 1.96 ± 0.95; P < 0.01). Jinlida granules can improve glycemic control and glycemic variability in patients with newly diagnosed type 2 diabetes. Clinical trial registration number: ChiCTR-IOR-16009296.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34495845

RESUMO

Collision detection is one of the most challenging tasks for unmanned aerial vehicles (UAVs). This is especially true for small or micro-UAVs due to their limited computational power. In nature, flying insects with compact and simple visual systems demonstrate their remarkable ability to navigate and avoid collision in complex environments. A good example of this is provided by locusts. They can avoid collisions in a dense swarm through the activity of a motion-based visual neuron called the Lobula giant movement detector (LGMD). The defining feature of the LGMD neuron is its preference for looming. As a flying insect's visual neuron, LGMD is considered to be an ideal basis for building UAV's collision detecting system. However, existing LGMD models cannot distinguish looming clearly from other visual cues, such as complex background movements caused by UAV agile flights. To address this issue, we proposed a new model implementing distributed spatial-temporal synaptic interactions, which is inspired by recent findings in locusts' synaptic morphology. We first introduced the locally distributed excitation to enhance the excitation caused by visual motion with preferred velocities. Then, radially extending temporal latency for inhibition is incorporated to compete with the distributed excitation and selectively suppress the nonpreferred visual motions. This spatial-temporal competition between excitation and inhibition in our model is, therefore, tuned to preferred image angular velocity representing looming rather than background movements with these distributed synaptic interactions. Systematic experiments have been conducted to verify the performance of the proposed model for UAV agile flights. The results have demonstrated that this new model enhances the looming selectivity in complex flying scenes considerably and has the potential to be implemented on embedded collision detection systems for small or micro-UAVs.

18.
Zhen Ci Yan Jiu ; 46(9): 800-3, 2021 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-34558248

RESUMO

Transcutaneous electrical acupoint stimulation (TEAS) has the characteristics of simple operation, non-invasive, and high patient acceptability, and is widely used in clinical practice. This article summarized the effects of TEAS on analgesia, gastrointestinal tract regulation, circulation regulation, postoperative cognitive function improvement, immune function regulation, anti-inflammatory and anti-stress during the perioperative period. At the same time, this article analyzed the problems of the application of TEAS in the perioperative period, and aimed to promote its clinical application.


Assuntos
Pontos de Acupuntura , Estimulação Elétrica Nervosa Transcutânea , Humanos , Período Perioperatório
19.
J Cancer ; 12(20): 6274-6284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539900

RESUMO

Ophiopogonin B (OP-B), a kind of saponin compound that exists in Radix Ophiopogonis is frequently adopted for the treatment of lung disease as traditional Chinese medicine. The present work aimed to explore the anti-tumor activity of OP-B on non-small cell lung carcinoma (NSCLC) and its possible mechanism. We found that OP-B-treated cells suppressed the viability and proliferation of cells depending on its concentration, as assayed by MTT and Alamar Blue (IC50 were 14.22 ± 1.94, 12.14 ± 2.01, and 16.11 ± 1.83 µM in A549, NCI-H1299, and NCI-H460 cells, respectively). Then, the suppressive effect of OP-B on the invasion and migration of NSCLC was observed through wound healing and Transwell assays, and the epithelial-mesenchymal transition (EMT) markers was detected by immunofluorescence and western blotting. In addition, a dose-dependent reduction of ß-catenin both within cytoplasm and nucleus was observed, and the downstream proteins cyclin D1 and c-Myc of Wnt/ß-catenin pathway were also reduced. We further constructed ß-catenin-overexpression cell models to reveal the underlying mechanism. The results showed that 10 µM of OP-B notably reduced ß-catenin protein levels, as well as cell migration and invasion. In spite of the increasement of ß-catenin, activation of Wnt pathway and EMT progression, knockdown of Axin leaded to de-function of OP-B on cell metastasis. Taken together, OP-B reduced NSCLC migration and invasion by strengthening the Axin/ß-catenin interaction and reducing ß-catenin protein translocation.

20.
Nanoscale ; 13(35): 14628-14635, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533156

RESUMO

Much of the richness and variety of physics today are based on coupling phenomena where multiple interacting systems hybridize into new ones with completely distinct attributes. Recent development in building van der Waals (vdWs) heterostructures from different 2D materials provides exciting possibilities in realizing novel coupling phenomena in a designable manner. Here, with a graphene/hBN/graphene heterostructure, we report near-field infrared nano-imaging of plasmon-plasmon coupling in two vertically separated graphene layers. Emergent symmetric and anti-symmetric coupling modes are directly observed simultaneously. Coupling and decoupling processes are systematically investigated with experiment, simulation and theory. The reported interlayer plasmon-plasmon coupling could serve as an extra degree of freedom to control light propagation at the deep sub-wavelength scale with low loss and provide exciting opportunities for optical chip integration.

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