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1.
Int J Biol Sci ; 18(7): 2867-2881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35541899

RESUMO

Background: There is increasing evidence that tumour-associated macrophages (TAMs) are critical in the formation of lung metastases. However, the molecular mechanisms of tumour interactions with TAMs via EMT are largely unknown. Methods: The mechanism of lung metastasis was studied in patient tissues. The mechanism of SNAIL regulation of the interaction between mesenchymal cells and M2 macrophages was elucidated using coculture of M2 macrophages and Transwell assays in vitro and in vivo in nude mice and NOD-SCID mice. Results: We demonstrated for the first time that SNAIL and CXCL2 were abnormally overexpressed in colorectal cancer, especially lung metastasis, and were associated with poor prognosis in colorectal cancer patients. We demonstrated that SNAIL promoted the secretion of CXCL2 by mesenchymal cells and induced the activation of M2 macrophages. We found that CXCL2 attracted M2-type macrophages to infiltrate and promote tumour metastasis. Conclusion: These findings suggest that SNAIL promotes epithelial tumour transformation, and that transformed mesenchymal cells secrete CXCL2, which promotes M2 macrophage infiltration and tumour cell metastasis. These findings elucidate the tumour-TAM interaction in the metastatic microenvironment, which is mediated by tumour-derived CXCL2 and affects lung metastasis. This study also provides a theoretical basis for the occurrence of secondary lung cancer.

2.
BMC Med Inform Decis Mak ; 22(1): 122, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35509058

RESUMO

Liver cancer is a malignant tumor with high morbidity and mortality, which has a tremendous negative impact on human survival. However, it is a challenging task to recognize tens of thousands of histopathological images of liver cancer by naked eye, which poses numerous challenges to inexperienced clinicians. In addition, factors such as long time-consuming, tedious work and huge number of images impose a great burden on clinical diagnosis. Therefore, our study combines convolutional neural networks with histopathology images and adopts a feature fusion approach to help clinicians efficiently discriminate the differentiation types of primary hepatocellular carcinoma histopathology images, thus improving their diagnostic efficiency and relieving their work pressure. In this study, for the first time, 73 patients with different differentiation types of primary liver cancer tumors were classified. We performed an adequate classification evaluation of liver cancer differentiation types using four pre-trained deep convolutional neural networks and nine different machine learning (ML) classifiers on a dataset of liver cancer histopathology images with multiple differentiation types. And the test set accuracy, validation set accuracy, running time with different strategies, precision, recall and F1 value were used for adequate comparative evaluation. Proved by experimental results, fusion networks (FuNet) structure is a good choice, which covers both channel attention and spatial attention, and suppresses channel interference with less information. Meanwhile, it can clarify the importance of each spatial location by learning the weights of different locations in space, then apply it to the study of classification of multi-differentiated types of liver cancer. In addition, in most cases, the Stacking-based integrated learning classifier outperforms other ML classifiers in the classification task of multi-differentiation types of liver cancer with the FuNet fusion strategy after dimensionality reduction of the fused features by principle component analysis (PCA) features, and a satisfactory result of 72.46% is achieved in the test set, which has certain practicality.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Aprendizado de Máquina , Redes Neurais de Computação
3.
Nat Commun ; 13(1): 2258, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474302

RESUMO

Organic semiconductors with high-spin ground states are fascinating because they could enable fundamental understanding on the spin-related phenomenon in light element and provide opportunities for organic magnetic and quantum materials. Although high-spin ground states have been observed in some quinoidal type small molecules or doped organic semiconductors, semiconducting polymers with high-spin at their neutral ground state are rarely reported. Here we report three high-mobility semiconducting polymers with different spin ground states. We show that polymer building blocks with small singlet-triplet energy gap (ΔES-T) could enable small ΔES-T gap and increase the diradical character in copolymers. We demonstrate that the electronic structure, spin density, and solid-state interchain interactions in the high-spin polymers are crucial for their ground states. Polymers with a triplet ground state (S = 1) could exhibit doublet (S = 1/2) behavior due to different spin distributions and solid-state interchain spin-spin interactions. Besides, these polymers showed outstanding charge transport properties with high hole/electron mobilities and can be both n- and p-doped with superior conductivities. Our results demonstrate a rational approach to obtain high-mobility semiconducting polymers with different spin ground states.

4.
Arch Environ Contam Toxicol ; 82(4): 455-466, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35430634

RESUMO

Several classes of pesticides have been shown to impair water quality in California, including organophosphates, pyrethroids and neonicotinoids. Vegetative treatment systems (VTS) can reduce pesticide loads and associated toxicity in agricultural runoff, but many water-soluble pesticides such as neonicotinoids are not effectively treated by VTS, and VTS installation is not always an option for growers required to remove non-crop vegetation for food safety concerns. Recent studies have shown that biochar filtration can be used to remove soluble contaminants, especially when coupled with other VTS components. We evaluated a mobile carbon filter system consisting of a trailer-mounted tank containing approximately 600L (~ 180 kg) of biochar. Input water from a 437-hectare agricultural drainage was pre-filtered and treated with biochar during two multi-week study periods. Laboratory toxicity tests and chemical and nutrient analyses were conducted on input and output water. Pesticide concentrations were initially reduced by greater than 99%. Treatment efficacy declined linearly and was expected to remain at least 50% effective for up to 34 weeks. Toxicity was assessed with Ceriodaphnia dubia, Hyalella azteca and Chironomus dilutus. Significant input toxicity was reduced to non-toxic levels in 6 of 16 samples. Some input concentrations of the neonicotinoid imidacloprid and the pyrethroid cypermethrin exceeded organism-specific toxicity thresholds and benchmarks, but the overall causes of toxicity were complex mixtures of agricultural chemicals. Nutrients were not reduced by the biochar. Results demonstrate the utility of biochar in treating agricultural runoff and provide measures of the longevity of biochar under field conditions.


Assuntos
Anfípodes , Inseticidas , Praguicidas , Poluentes Químicos da Água , Agricultura , Animais , Carbono , Inseticidas/análise , Neonicotinoides/análise , Praguicidas/análise , Praguicidas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-35457385

RESUMO

Disaster preparation can reduce the impact of an earthquake on residents. Residents are more likely to undertake disaster preparedness if they perceive it to be effective. However, few studies have analyzed the influence of trust on this perception. This study surveyed 327 households in areas stricken by the Wenchuan and Lushan earthquakes to explore these issues. Trust was divided into government trust, emotional trust, and social trust, while the efficacy of disaster preparedness was divided into self-efficacy and response efficacy. A partial least squares structural equation model was used to explore the influence of trust on perceptions of the efficacy of disaster preparedness. The results show that: (1) government trust can directly increase perceived efficacy and indirectly increase self-efficacy via emotional trust; (2) emotional trust can directly increase self-efficacy; (3) social trust can directly reduce self-efficacy while indirectly increasing it by increasing emotional trust. This study deepens our understanding of the relationship between trust and perceptions of the efficacy of disaster preparedness. This study can provide inspiration to improve risk communication and construct systems of community-based disaster-prevention.


Assuntos
Desastres , Terremotos , China , Humanos , População Rural , Confiança
6.
J Med Chem ; 65(7): 5850-5865, 2022 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-35380045

RESUMO

Novel enzyme-triggerable cell penetrating peptide (ETCPP) dendrimers with a camptothecin (CPT) warhead were designed and synthesized based on an amphiphilic penetrating peptide (FKKFFRKLL, discovered by us before). Among the newly synthesized ETCPP dendrimer conjugates, BL_Oc-SS-CPT (a high-generation dendrimer) exhibited the highest activity with IC50s in the nanomolar range (31-747 nM) against a panel of cancer cells, which is 3-10 times better than that of CPT. BL_Oc-SS-CPT remained intact during transit to target cells and in normal tissues with a plasma half-life of 4.2 h, 2.3-fold longer than that of the monomer (1.8 h). Once reaching the tumor site, BL_Oc-SS-CPT gradually released CPT in the presence of excessive matrix metalloproteinase-2/9 and GSH in cancer cells. Importantly, BL_Oc-SS-CPT exhibited excellent in vivo tumor targeting capability and antitumor efficacy with benign toxicity profiles. Thus, the novel ETCPP dendrimer-based drug delivery system (e.g., BL_Oc-SS-CPT) represents a safe and effective strategy for targeted cancer therapy.


Assuntos
Camptotecina , Peptídeos Penetradores de Células , Dendrímeros , Sistemas de Liberação de Medicamentos , Neoplasias , Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/farmacologia , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/farmacologia , Desenho de Fármacos , Humanos , Metaloproteinase 2 da Matriz , Neoplasias/tratamento farmacológico
7.
J Hazard Mater ; 434: 128895, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35429752

RESUMO

Microplastics (MPs) are ubiquitous in aquatic environments, which are important carriers of emerging contaminants (ECs). Biofilms can be attached to the surface of MPs in a natural aquatic environment, which may influence chemical adsorption; however, knowledge of its impact is still limited. This study investigated the effect of biofilms on MPs on the adsorption of ECs through field-laboratory exposure experiments. Three types of MPs were naturally colonized with biofilms in lake. Then, biofilm-absent/biofilm-attached MPs were exposed to nine EC solutions at a concentration of 8 µg/L of each compound in laboratory. Most compounds exhibited 3.8 times lower concentrations on biofilm-attached MPs than on biofilm-absent MPs; only a few compounds showed enhanced adsorption. Pseudo-equilibrium was achieved within 72 h based on adsorption kinetics, implying fast adsorption of ECs on biofilm-attached MPs. The partition coefficients (Kd) for biofilm-attached MPs were 0.14 (diclofenac) to 535 (miconazole) L/kg and were positively correlated with octanol/water partition coefficients (Kow). This indicated that chemical properties (such as Kow) of the compounds determined their final adsorption amounts on MPs, although these were influenced by the presence of the biofilm. Hence, multiple influencing factors should be considered when evaluating the carrier potential of MPs for ECs in aquatic environments.

8.
Food Chem ; 386: 132753, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35367801

RESUMO

The residues of bisphenol A (BPA) in milk packaging may transfer to milk, adversely affecting the human endocrine system. Consequently, to analyse or monitor BPA, it is imperative to develop rapid and effective approaches to BPA extraction from milk and milk packing as BPA is usually present in trace levels. Herein, we developed a rapid, simple, and low-cost dispersive-membrane-solid-phase-extraction (DME) for BPA with MIL-101(Cr) mixed-matrix-membrane (MMM). The MMM had large surface area (1322.09 m2/g) and pore volume (0.65 cm3/g), possessed great extraction efficiency of BPA, and kept more than 90% extraction efficiency after 20 times of reuse. Using the developed MIL-101(Cr)-MMM-based DME coupled with HPLC-fluorescence detector, we received an adequate linearity in the range of 0.1 âˆ¼ 50 µg/L BPA and a limit of detection as low as 16 ng/L under optimized conditions. The recoveries of BPA in milk and milk bottles were from 74.2% to 110.6%, with RSDs less than 9.4%.


Assuntos
Estruturas Metalorgânicas , Leite , Animais , Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão , Humanos , Estruturas Metalorgânicas/química , Leite/química , Fenóis , Extração em Fase Sólida
9.
Artigo em Inglês | MEDLINE | ID: mdl-35443095

RESUMO

The 'solid catalyst with ionic liquid layer' (SCILL) is an extremely successful new concept in heterogeneous catalysis. The idea is to boost the selectivity of a catalyst by its modification with an ionic liquid (IL). Here, we show that it is possible to use the same concept in electrocatalysis for the selective transformation of organic compounds. We scrutinize the electrooxidation of 2,3-butane-diol, a reaction which yields two products, singly oxidized acetoin and doubly oxidized diacetyl. When adding the IL (1-ethyl-3-methyl-imidazolium trifluormethanesulfonate, [C 2 C 1 Im][OTf]), the selectivity for acetoin increases drastically. By in-situ spectros-copy, we analyze the underlying mechanism: Specific adsorption of the IL anions suppresses the activation of water for the second oxidation step and, thus, enhances the selectivity for acetoin. Our study demonstrates the great potential of this approach for selective transformation of organic compounds.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35445303

RESUMO

Encouraging rural residents to adopt biogas is of great practical significance in tackling environmental degradation in China. Based on the survey data of 540 rural households in Sichuan Province, China, this paper studies the peer effects of biogas adoption in rural households, focusing on the influence of relatives and friends on the biogas adoption behavior of rural households. According to whether there is a Chinese New Year visit, the relatives and friends of rural households are divided into strong ties and weak ties. The peer effects are further discussed from the perspective of strong and weak ties, and the probability score matching (PSM) method is used to correct the estimation errors that may be caused by selection bias. In addition, the study further revealed the internal mechanism of peer effects through heterogeneity analysis. The results found that (1) the adoption of biogas by relatives and friends significantly promotes the adoption of biogas in rural households. (2) Compared with relatives and friends who did not visit during the Chinese New Year (weak ties), relatives and friends who visited (strong ties) had a more significant impact on the biogas adoption behavior of rural families. (3) Farmer groups with lower education levels and farther from the market are more affected by the peer effects and are more likely to adopt biogas. The driving effect of biogas behavior choice of relatives and friends on biogas behavior decision of rural households can provide a reference for decision-makers to make relevant measures.

11.
J Healthc Eng ; 2022: 4190668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299690

RESUMO

In this paper, we are going to analyze the influence of mixed teaching mode on the teaching effect of psychology students' experiment courses in higher vocational colleges. To realize and verify these claims, 80 psychology students of grade 2020 in our school were selected for observation. Class 1 of the psychology major in our school was randomly selected as the observation group (n = 40) and Class 2 as the control group (n = 40). The mixed teaching mode and the traditional teaching mode were adopted, respectively. After intervention, the experimental examination results, experimental report score, general evaluation results of the experiment, and experimental pass rate of the observation group were higher than those before intervention (P < 0.05). The control group had no significant change before and after intervention (P > 0.05). The experimental examination results, experimental report score, general evaluation results of the experiment, and experimental pass rate of the observation group were all higher than those of the control group, with statistical significance (P < 0.05). The results show that in the observation group, 92.50% of the students believed that the mixed teaching mode could arouse the enthusiasm for learning and improve the activity of the experimental class. 97.50% of the students thought that the mixed teaching mode could stimulate students' interest in learning and improve the ability of experimental operation. 100.00% of the students thought the mixed teaching mode could be helpful in understanding the experimental. The evaluation result of the teaching mode was significantly higher than that of the control group, and the comparison result was statistically significant (P < 0.05). After receiving the mixed teaching mode, the observation group had a higher satisfaction with the teaching effect, with a satisfaction rate of 95.00%. The control group had low satisfaction with the teaching effect, with a satisfaction rate of 52.50%, and the difference was statistically significant (P < 0.05). Through the application of the mixed teaching mode combining online and offline, psychology students in higher vocational colleges can achieve better learning results and improve students' evaluation and satisfaction of teaching effect of the mixed teaching mode of psychology experiment teaching mode in higher vocational colleges.


Assuntos
Aprendizagem , Estudantes , Humanos , Universidades
12.
Exp Ther Med ; 23(4): 297, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35340881

RESUMO

Endoscopic retrograde cholangiopancreatography (ERCP) is not always successful when difficult biliary cannulation occurs. A second ERCP seems to be a worthwhile option following initial failure cannulation; however, relevant data are limited. Thus, the aim of the present study was to determine the outcomes of repeating ERCP in patients in whom the first biliary cannulation with or without precut sphincterotomy failed. It retrospectively analyzed 4,136 patients who underwent an initial biliary access between June 2016 and September 2020. Data from our databases were analyzed. Efficacy was based on the cannulation rate of the second ERCP and safety was assessed in terms of adverse events. Of 94 patients, 56 (59.6%) underwent a second ERCP and the success rate in biliary cannulation was 83.9% (47 of 56). The median operative time in the second ERCP was shorter than that in the initial procedure (47 vs. 65 min, P<0.001). A total of 5 patients (8.9%) suffered from mild ERCP-associated complications following the second ERCP. Compared with patients that did not undergo a second ERCP, patients that underwent a second ERCP had a lower 30-day mortality rate (13.2 vs. 1.8%, P=0.038). In addition, by univariate and multivariate analysis, it was observed that normal preoperative serum bilirubin levels and an interval time of <3 days were correlated with the cannulation failure of a second ERCP (OR=9.211, P=0.019, OR=6.765, P=0.041, respectively). A second ERCP following failure of an initial biliary cannulation appears to be safe and effective. For most clinically stable patients with an unsuccessful initial ERCP, a second ERCP after 2-4 days may be an optimal strategy. Preoperative normal serum bilirubin levels may be a risk factor that can be used for predicting cannulation failure of a second ERCP procedure.

13.
Disaster Med Public Health Prep ; : 1-11, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35293307

RESUMO

OBJECTIVE: The purpose of this study is to further deepen our understanding of the relationship between community resilience and disaster risk perception of residents, so as to provide beneficial enlightenment for the construction of community resilience disaster prevention system and disaster risk management. METHODS: This study surveyed 327 rural households in four counties of Sichuan Province, China, that were affected by the Wenchuan and Lushan earthquakes. Community disaster resilience was divided into five dimensions: connection and caring, resources, transformative potential, disaster management, and information and communication. Residents' disaster risk perception was divided into three dimensions: possibility, threat, and worry. This study analyzed the characteristics of community disaster resilience and residents' disaster risk perceptions. Ordinary least squares (OLS) methods were used to explore the correlations between these factors. RESULTS: The results show that (1) Residents' overall disaster risk perception was at a moderate level, and the community's overall disaster resilience were above the moderate level. (2) Community connection and caring has a positive significant correlation with the possibility perception of disaster occurrence; transformative potential has a negative significant correlation with the possibility perception of disaster occurrence; the overall community disaster resilience has negative significant correlations with the possibility and the overall residents' perception of disaster risk occurrence. CONCLUSIONS: The implication for the local government is that the government should appropriately increase its contact with external institutions/organizations, especially some Non-Governmental Organization, to strengthen the resilience and disaster prevention capacity of the community. Establish and improve information and communication networks to ensure the timely and effective transmission of effective disaster information, and strengthen the supervision of the dissemination of false information to reduce the losses caused by false information to residents. Attention should be paid to psychological counseling for people in disaster-hit areas to reduce the psychological trauma of the disaster.

14.
Front Cell Neurosci ; 16: 792089, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250483

RESUMO

Functional hair cell regeneration in the adult mammalian inner ear remains challenging. This study aimed to study the function of new hair cells induced by a DNA demethylating agent 5-azacytidine. Adult mice were deafened chemically, followed by injection of 5-azacytidine or vehicle into the inner ear. Functionality of regenerated hair cells was evaluated by expression of hair cell proteins, auditory brainstem response (ABR), and distortion-product otoacoustic emission (DPOAE) tests for 6 weeks. In the vehicle-treated group, no cells expressed the hair cell-specific protein myosin VIIa in the cochlea, whereas numerous myosin VIIa-expressing cells were found in the 5-azacytidine-treated cochlea, suggesting the regeneration of auditory hair cells. Moreover, regenerated hair cells were co-labeled with functional proteins espin and prestin. Expression of ribbon synapse proteins suggested synapse formation between new hair cells and neurons. In hearing tests, progressive improvements in ABR [5-30 dB sound pressure level (SPL)] and DPOAE (5-20 dB) thresholds were observed in 5-azacytidine-treated mice. In vehicle-treated mice, there were <5 dB threshold changes in hearing tests. This study demonstrated the ability of 5-azacytidine to promote the functional regeneration of auditory hair cells in a mature mouse model via DNA demethylation, which may provide insights into hearing regeneration using an epigenetic approach.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35206573

RESUMO

For residents living in earthquake-threatened areas, choosing suitable risk coping behaviors can effectively reduce the loss of family life and property. However, some residents still choose to continue to live within areas at risk of earthquake disaster. Place attachment may play an important role. Based on place attachment theory and the Protective Action Decision Model (PADM), this study explores the possible relationships among place attachment, efficacy beliefs, and evacuation/relocation intention. Furthermore, it examines the mediating role of efficacy beliefs. The study also used the partial least squares method (PLS-SEM) to test samples of 327 rural households in Wenchuan and Lushan earthquake-hit areas. The results show that: (1) Place attachment has a significant effect on response efficacy (RE), but not on self-efficacy (SE); (2) Place dependence (PD) has a negative and significant effect on relocation intention (RI) but has no significant effect on evacuation intention (EI). However, place identity (PI) can indirectly affect EI by influencing RE; (3) Efficacy beliefs have a significant positive effect on EI and RI. These results help us understand the complex relationships among place attachment, efficacy beliefs, and residents' risk coping behavior, thus providing decision-making references for the formulation and improvement of regional disaster risk management policies.


Assuntos
Desastres , Terremotos , Adaptação Psicológica , Características da Família , Humanos , População Rural
16.
Elife ; 112022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35199645

RESUMO

Atmospheric Particulate Matter (PM) is one of the leading environmental risk factors for the global burden of disease. Increasing epidemiological studies demonstrated that PM plays a significant role in CNS demyelinating disorders; however, there is no direct testimony of this, and yet the molecular mechanism by which the occurrence remains unclear. Using multiple in vivo and in vitro strategies, in the present study we demonstrate that PM exposure aggravates neuroinflammation, myelin injury, and dysfunction of movement coordination ability via boosting microglial pro-inflammatory activities, in both the pathological demyelination and physiological myelinogenesis animal models. Indeed, pharmacological disturbance combined with RNA-seq and ChIP-seq suggests that TLR-4/NF-kB signaling mediated a core network of genes that control PM-triggered microglia pathogenicity. In summary, our study defines a novel atmospheric environmental mechanism that mediates PM-aggravated microglia pathogenic activities, and establishes a systematic approach for the investigation of the effects of environmental exposure in neurologic disorders.


Assuntos
Doenças Desmielinizantes , NF-kappa B , Animais , Doenças Desmielinizantes/patologia , Microglia/patologia , Material Particulado/toxicidade , Receptor 4 Toll-Like/genética
17.
Int J Ophthalmol ; 15(2): 255-260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186685

RESUMO

AIM: To investigate the feasibility of teaching minimally invasive vitreoretinal surgery with a robot-assisted surgical system and a three-dimensional (3D) visualization system. METHODS: Enucleated porcine eyes were established as an animal model for removing foreign bodies. Forty medical students were recruited to remove foreign bodies to compare the traditional microscope and the 3D system. One junior resident performed the surgical task with manual and robot-assisted operations on 20 porcine eyes for each group. One senior surgeon evaluated the retinal invasion by a graded injury degree. The learning curve for minimally invasive vitreoretinal surgery was described. RESULTS: Compared with the robot-assisted group, the injury degree was higher in the manual group. For the first ten surgeries, the manual and robot-assisted groups had injuries of 2.60±1.35 (4 to 0) and 1.80±1.62 (4 to 0), respectively. For the last ten surgeries, the injury degrees were 1.90±1.20 (3 to 0) and 0.80±0.42 (1 to 0). Considering the manual and robot-assisted groups together, 95%, 75% and 60% of the students considered surgical manipulation with the 3D visualization system to be more comfortable, easier and clearer, respectively. CONCLUSION: The robot-assisted surgical system and 3D visualization system may have value in teaching minimally invasive vitreoretinal surgery.

18.
Nanomaterials (Basel) ; 12(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35159840

RESUMO

Due to their broadband optical absorption ability and fast response times, carbon nanotube (CNT)-based materials are considered promising alternatives to the toxic compounds used in commercial infrared sensors. However, the direct use of pure CNT networks as infrared sensors for simple resistance read-outs results in low sensitivity values. In this work, MoS2 nanoflowers are composited with CNT networks via a facile hydrothermal process to increase the bolometric performance. The thermal diffusivity (α) against temperature (T) is measured using the transient electro-thermal (TET) technique in the range of 320 K to 296 K. The α-T curve demonstrates that the composite containing MoS2 nanoflowers provides significant phonon scattering and affects the intertube interfaces, decreasing the α value by 51%. As the temperature increases from 296 K to 320 K, the relative temperature coefficient of resistance (TCR) increases from 0.04%/K to 0.25%/K. Combined with the enhanced light absorption and strong anisotropic structure, this CNT-MoS2 composite network exhibits a more than 5-fold greater surface temperature increase under the same laser irradiation. It shows up to 18-fold enhancements in resistive responsivity ((Ron - Roff)/Roff) compared with the pure CNT network for a 1550 nm laser at room temperature (RT).

19.
Artigo em Inglês | MEDLINE | ID: mdl-35162139

RESUMO

At present, the world's countryside needs to be revitalized urgently, and cultivated land is the critical factor in promoting the countryside's revitalization. The reduction of uncultivated land contributes to the efficient use of rural land resources, contributing to global rural revitalization. This study uses data from 3938 Chinese peasant households conducted in 2014 and the OLS method to investigate the quantitative impact of institutional social insurance on cultivated land abandonment. The empirical results point to the following conclusions: (1) Institutional social insurance will weaken the social insurance function of land, which will lead to the generation of peasant households' cultivated land abandonment. More specifically, for every 1% increase in the level of institutional social insurance of peasant households, the area of cultivated land abandoned increased by 0.002 mu; (2) The influence of institutional social insurance on peasant households' cultivated land abandonment is heterogeneous, that is, endowment insurance can weaken the social insurance function of land more than medical insurance, and households with a higher proportion of pensioners are more likely to abandon cultivated land. This study's conclusions may help understand the relationship between institutional and non-institutional social insurance and provide a reference for the effective use of cultivated land resources in the global rural revitalization.


Assuntos
População Rural , Previdência Social , Agricultura/métodos , China , Meio Ambiente , Características da Família , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-35105686

RESUMO

BACKGROUND AND OBJECTIVES: Demyelinating diseases in the CNS are characterized by myelin sheath destruction or formation disorder that leads to severe neurologic dysfunction. Remission of such diseases is largely dependent on the differentiation of oligodendrocytes precursor cells (OPCs) into mature myelin-forming OLGs at the demyelinated lesions, which is defined as remyelination. We discover that baicalin (BA), a natural flavonoid, in addition to its well-known antiinflammatory effects, directly stimulates OLG maturation and CNS myelin repair. METHODS: To investigate the function of BA on CNS remyelination, we develop the complementary in vivo and in vitro models, including physiologic neonatal mouse CNS myelinogenesis model, pathologic cuprizone-induced (CPZ-induced) toxic demyelination model, and postnatal OLG maturation assay. Furthermore, molecular docking, pharmacologic regulation, and transgenic heterozygous mice were used to clarify the target and action of the mechanism of BA on myelin repair promotion. RESULTS: Administration of BA was not only merely effectively enhanced CNS myelinogenesis during postnatal development but also promoted remyelination and reversed the coordination movement disorder in the CPZ-induced toxic demyelination model. Of note, myelin-promoting effects of BA on myelination or regeneration is peroxisome proliferator-activated receptor γ (PPARγ) signaling-dependent. DISCUSSION: Our work demonstrated that BA promotes myelin production and regeneration by activating the PPARγ signal pathway and also confirmed that BA is an effective natural product for the treatment of demyelinating diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Doenças Desmielinizantes/tratamento farmacológico , Flavonoides/farmacologia , Transtornos das Habilidades Motoras/tratamento farmacológico , PPAR gama/efeitos dos fármacos , Remielinização/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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