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1.
Nat Commun ; 14(1): 6323, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816725

RESUMO

Structural superlubricity, a state of nearly zero friction and no wear between two contact surfaces under relative sliding, holds immense potential for research and application prospects in micro-electro-mechanical systems devices, mechanical engineering, and energy resources. A critical step towards the practical application of structural superlubricity is the mass transfer and high throughput performance evaluation. Limited by the yield rate of material preparation, existing automated systems, such as roll printing or massive stamping, are inadequate for this task. In this paper, a machine learning-assisted system is proposed to realize fully automated selective transfer and tribological performance measurement for structural superlubricity materials. Specifically, the system has a judgment accuracy of over 98% for the selection of micro-scale graphite flakes with structural superlubricity properties and complete the 100 graphite flakes assembly array to form various pre-designed patterns within 100 mins, which is 15 times faster than manual operation. Besides, the system is capable of automatically measuring the tribological performance of over 100 selected flakes on Si3N4, delivering statistical results for new interface which is beyond the reach of traditional methods. With its high accuracy, efficiency, and robustness, this machine learning-assisted system promotes the fundamental research and practical application of structural superlubricity.

2.
Nat Commun ; 14(1): 2931, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37217500

RESUMO

Structural superlubricity is a state of nearly zero friction and no wear between two contacted solid surfaces. However, such state has a certain probability of failure due to the edge defects of graphite flake. Here, we achieve robust structural superlubricity state between microscale graphite flakes and nanostructured silicon surfaces under ambient condition. We find that the friction is always less than 1 µN, the differential friction coefficient is on the order of 10-4, without observable wear. This is attributed to the edge warping of graphite flake on the nanostructured surface under concentrated force, which eliminate the edge interaction between the graphite flake and the substrate. This study not only challenges the traditional understanding in tribology and structural superlubricity that rougher surfaces lead to higher friction and lead to wear, thereby reducing roughness requirements, but also demonstrates that a graphite flake with a single crystal surface that does not come into edge contact with the substrate can consistently achieve robust structural superlubricity state with any non-van der Waals material in atmospheric conditions. Additionally, the study provides a general surface modification method that enables the widespread application of structural superlubricity technology in atmospheric environments.

4.
J Clin Neurosci ; 106: 219-225, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36371301

RESUMO

BACKGROUND: Facial emotion perception and recognition (FEPR) deficits are the sources of disability, impaired social relationship, and reduced quality of life. Studies of unilateral acute ischemic stroke (AIS) remain controversial about FEPR deficits. METHODS: Clinical and neurocognitive data were collected and analyzed among normal controls (NC) and AIS patients with left brain damage (LBD), right brain damage (RBD), and infratentorial brain damage (IBD). To assess FEPR, all participants completed a localization test (the Southeastern China Brief Affect Recognition Test). Correlation analyses were conducted between the FEPR deficits and cognitive functions. RESULTS: Compared with NC, all three groups of AIS patients reported significant FEPR deficits. Although no statistical difference in FEPR deficits were observed among the LBD, RBD and IBD patients, the deficit patterns were markedly different. FEPR deficits were positively correlated with cognitive impairment. CONCLUSIONS: FEPR deficits may occur in AIS patients and are associated with impaired cognitive functions, where the cerebral hemispheres and the infratentorial brain are jointly involved. Early recognition and early intervention of FEPR deficits in AIS patients are critical for post-stroke rehabilitation, reconstruction of social function and improvement in life quality.


Assuntos
Reconhecimento Facial , AVC Isquêmico , Humanos , Qualidade de Vida , Reconhecimento Psicológico , Emoções , Expressão Facial , Testes Neuropsicológicos
5.
J Inflamm Res ; 15: 5075-5088, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091333

RESUMO

Background: Altered lipid metabolism is associated with gastric cancer (GC) progression. Comprehensive analysis to identify critical lipid metabolic drivers for predicting overall survival (OS) is not fully elucidated in GC. Our study aim to explore a novel lipid metabolism-related prognostic marker for GC. Methods: Transcriptional status and clinical features were obtained from the TCGA-STAD database. The differentially expressed lipid metabolic genes and the risk prognostic model were developed by using bioinformatics and Cox regression analyses. ROC and Kaplan-Meier analysis were established to assess the performance of the risk predictive score model. GSE84437 dataset was used for external validation. Immunochemistry (IHC) was used to examine the expression of CYP19A1 in GC patients. Gene Set Enrichment Analysis (GSEA) was conducted to elucidate the underlying enriched mechanisms. TIMER and CIBERSORT analysis were performed to explore the relationship between CYP19A1 and immune microenvironment. Results: A novel lipid metabolic gene signature (including MTTP, CYP19A1, MYB, SERPINE1), and specifically CYP19A1, might be a promising prognostic factor for GC. Using the validation cohort, ROC curves indicate a good showing of our risk model. Based on the signature yielded a significant difference OS time between the low- and high-risk groups. Cox regression indicates that the signature is an independent prognostic variable. ROC curves present better and reliability predictive accuracy. The IHC data validate that high expression of CYP19A1 was found in GC tissues. GSEA analysis reveals that higher expression of CYP19A1 may significantly up-regulate genes involved in fatty acid metabolism and glycerolipid metabolism. CIBERSORT analysis suggests that CYP19A1 is related to the infiltration of multiple immune cells. Conclusion: CYP19A1 could be an independent prognostic factor and a novel metabolic-targeted treatment strategy for gastric cancer.

6.
Technol Health Care ; 30(6): 1489-1502, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599513

RESUMO

BACKGROUND: The injury of the knee joint is found to be directly related to the fatigue caused by excessive exercise. Many previous studies used wearable devices to measure the angle of knee joint during activities, but did not pay enough attention to the load of knee joint related to the fatigue degree of it. OBJECTIVE: A wearable embedded system was designed to sense the motion state and load of knee joint and uses the sensoring data to estimate and predict the fatigue degree of knee joint during exercise in real time, so as to prevent it from being injured. METHODS: An economical wearable system is designed to measure the parameters of the knee joint during exercises. Then the warning message and recommended healthy lasting time are able to be sent to users to avoid excessive exercise. 24 healthy volunteers aged 20-25 years were involved in the experiments. Two famous evaluation scales for knee joint from Department of Orthopedics (Lysholm score and IKDC score) were adopted to evaluate the protective effect. RESULTS: After 14 days of the first stage testing, all the participants with wearable devices reported healthy knee joint state to verify the effectiveness of the system. For the second stage, the testing group equipped with wearable warning devices did not receive obvious change in the two scales. However, Lysholm score of control group dropped by at least 7.4 and IKDC score dropped by at least 11.1 which were significantly reduced. CONCLUSION: Only using human perception to prevent knee joint fatigue had a risk of failure while the designed wearable system could protect the knee successfully from injuries during exercises, such as running, badminton, table tennis and basketball. Moreover, female gender and a high BMI value may be two factors that increase the risk of knee injuries during sports.


Assuntos
Traumatismos do Joelho , Esportes , Dispositivos Eletrônicos Vestíveis , Feminino , Humanos , Articulação do Joelho , Fadiga
7.
PeerJ ; 10: e12871, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35178302

RESUMO

BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) remains one of the most common respiratory tumors worldwide. Baculoviral inhibitor of apoptosis repeat containing 5 (BIRC5) is a member of the inhibitor-of-apoptosis protein family. BIRC5 plays an important role in various types of cell proliferation, differentiation, migration and invasion. However, the specific role of BIRC5 in LSCC remains unclear. METHODS: To provide a prognostic biomarker for LSCC, we screened the prognostic genes of LSCC via bioinformatics. PPI network and KEGG pathways were used to select hub genes. Clinical prognoses were performed using a Kaplan-Meier plotter and Cox proportional-hazard analysis. BIRC5 expression in LSCC tissues and cell lines were detected by RT-PCR, Western blot and Immunohistochemistry (IHC). Cell proliferation, cell cycle and cell apoptosis were detected with Cell Counting Kit-8 (CCK-8) and Flow Cytometry assay, respectively. RESULTS: Here, BIRC5 was strongly correlated with higher tumor grade and differentiation. BIRC5 was highly expressed in LSCC tissues when compared with normal tissues and increased expression of BIRC5 was associated with overall survival in LSCC patients. The suppression of BIRC5 induced cell apoptosis and cell cycle arrest, thereby inhibiting the proliferation of LSCC cells. The survival analysis confirmed that higher level of BIRC5 expression predicted poor prognosis of LSCC patients. BIRC5 may act as an oncogene of LSCC development and was suggested as a promising prognostic biomarker for LSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Laríngeas , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias Laríngeas/genética , Carcinoma de Células Escamosas/genética , Prognóstico , Processos Neoplásicos , Biomarcadores , Survivina/genética
8.
Chin Med J (Engl) ; 135(2): 205-215, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732662

RESUMO

BACKGROUND: Microglia plays an indispensable role in the pathological process of sleep deprivation (SD). Here, the potential role of microglial CX3C-chemokine receptor 1 (CX3CR1) in modulating the cognition decline during SD was evaluated in terms of microglial neuroinflammation and synaptic pruning. In this study, we aimed to investigat whether the interference in the microglial function by the CX3CR1 knockout affects the CNS's response to SD. METHODS: Middle-aged wild-type (WT) C57BL/6 and CX3CR1-/- mice were either subjected to SD or allowed normal sleep (S) for 8 h to mimic the pathophysiological changes of middle-aged people after staying up all night. After which, behavioral and histological tests were used to explore their different changes. RESULTS: CX3CR1 deficiency prevented SD-induced cognitive impairments, unlike WT groups. Compared with the CX3CR1-/- S group, the CX3CR1-/- SD mice reported a markedly decreased microglia and cellular oncogene fos density in the dentate gyrus (DG), decreased expression of pro-inflammatory cytokines, and decreased microglial phagocytosis-related factors, whereas increased levels of anti-inflammatory cytokines in the hippocampus and a significant increase in the density of spines of the DG were also noted. CONCLUSIONS: These findings suggest that CX3CR1 deficiency leads to different cerebral behaviors and responses to SD. The inflammation-attenuating activity and the related modification of synaptic pruning are possible mechanism candidates, which indicate CX3CR1 as a candidate therapeutic target for the prevention of the sleep loss-induced cognitive impairments.


Assuntos
Disfunção Cognitiva , Privação do Sono , Animais , Camundongos , Camundongos Endogâmicos C57BL , Microglia , Doenças Neuroinflamatórias
9.
Biochem Biophys Res Commun ; 567: 63-71, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34144502

RESUMO

Hepatocellular carcinoma (HCC) has received extensive attention from clinical and scientific researchers due to its high incidence and refractory nature. Searching for HCC prognostic markers and gene therapy targets are key research efforts. The FAM83 protein family has been reported to promote tumor growth and metastasis in a variety of tumors, and many of its members are closely related to HCC. Multiple public databases showed that FAM83G is highly expressed in HCC patients and is associated with poor prognosis, but there is currently no relevant research evidence to verify its exact role in HCC. Through clinical data analysis, we found that increased expression of FAM83G is associated with early HCC metastasis and a high recurrence rate and indicates a poor survival rate. Both in vivo and in vitro experiments confirmed that FAM83G overexpression significantly promoted the proliferation, migration, and invasion of HCC cells, while inhibiting its expression reversed the above results. Mechanistic analysis indicated that FAM83G overexpression was accompanied by over-activation of PI3K/AKT pathway signaling, a combined increase of Cyclin D1 protein and decrease of p21 protein, and increased expression of EMT-related signal, which was manifested in the decrease of E-cadherin and the increase of N-cadherin and snail. Finally, we found that FAM83G activated PI3K/AKT signaling by directly binding with the PI3K-p85 subunit to promote its phosphorylation. In conclusion, FAM83G, as a tumor-promoting factor, can predict the poor prognosis of HCC patients and can significantly promote the proliferation, invasion, and migration of HCC cells by stimulating the PI3K/AKT signaling pathway and related downstream signals.


Assuntos
Carcinoma Hepatocelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/patologia
11.
Front Neurol ; 12: 658266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868158

RESUMO

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy in which most patients have cranial nerve involvement, with facial nerve involvement being the most common. However, delayed facial palsy (DFP) with asymmetric facial palsy is a rare manifestation of GBS, and the mechanism is unclear. We report a case of GBS combined with delayed unilateral facial palsy and review previously reported cases of GBS combined with DFP. A total of 28 cases of GBS with DFP, including the case in this report, were included in this study. The occurrence of DFP may be related to early subclinical demyelination of the facial nerve, the blood-nerve barrier of the facial nerve, facial movement, and descending reversible paralysis. The occurrence of unilateral facial palsy may be related to Campylobacter jejuni, specific anti-ganglioside antibodies, and the site of central nervous system anatomical involvement. There is no evidence that immunotherapy is related to the shortening of DFP course and improving patients' prognosis.

12.
Nat Commun ; 12(1): 2268, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859180

RESUMO

Miniaturized or microscale generators that can effectively convert weak and random mechanical energy into electricity have significant potential to provide solutions for the power supply problem of distributed devices. However, owing to the common occurrence of friction and wear, all such generators developed so far have failed to simultaneously achieve sufficiently high current density and sufficiently long lifetime, which are crucial for real-world applications. To address this issue, we invent a microscale Schottky superlubric generator (S-SLG), such that the sliding contact between microsized graphite flakes and n-type silicon is in a structural superlubric state (an ultra-low friction and wearless state). The S-SLG not only generates high current (~210 Am-2) and power (~7 Wm-2) densities, but also achieves a long lifetime of at least 5,000 cycles, while maintaining stable high electrical current density (~119 Am-2). No current decay and wear are observed during the experiment, indicating that the actual persistence of the S-SLG is enduring or virtually unlimited. By excluding the mechanism of friction-induced excitation in the S-SLG, we further demonstrate an electronic drift process during relative sliding using a quasi-static semiconductor finite element simulation. Our work may guide and accelerate the future use of S-SLGs in real-world applications.

13.
BMC Health Serv Res ; 21(1): 288, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789627

RESUMO

BACKGROUND: Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, the stroke care systems have been seriously affected because of social restrictions and other reasons. As the pandemic continues to spread globally, it is of great significance to understand how COVID-19 affects the stroke care systems in mainland China. METHODS: We retrospectively studied the real-world data of one comprehensive stroke center in mainland China from January to February 2020 and compared it with the data collected during the same period in 2019. We analyzed DTN time, onset-to-door time, severity, effects after treatment, the hospital length of stays, costs of hospitalization, etc., and the correlation between medical burden and prognosis of acute ischemic stroke (AIS) patients. RESULTS: The COVID-19 pandemic was most severe in mainland China in January and February 2020. During the pandemic, there were no differences in pre-hospital or in-hospital workflow metrics (all p>0.05), while the degree of neurological deficit on admission and at discharge, the effects after treatment, and the long-term prognosis were all worse (all p<0.05). The severity and prognosis of AIS patients were positively correlated with the hospital length of stays and total costs of hospitalization (all p<0.05). CONCLUSIONS: COVID-19 pandemic is threatening the stroke care systems. Measures must be taken to minimize the collateral damage caused by COVID-19.


Assuntos
Isquemia Encefálica , COVID-19 , Atenção à Saúde/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Acidente Vascular Cerebral , Tempo para o Tratamento , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/terapia , COVID-19/epidemiologia , China/epidemiologia , Serviços Médicos de Emergência , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia
14.
Front Aging Neurosci ; 12: 594701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240078

RESUMO

The effective management and therapies for Parkinson's disease (PD) require appropriate clinical evaluation. The Parkinson's KinetiGraph (PKG) is a wearable sensor system that can monitor the motion characteristics of PD objectively and continuously. This study was aimed to assess the correlations between PKG data and clinical scores of bradykinesia, rigidity, tremor, and fluctuation. It also aims to explore the application value of identifying early motor symptoms. An observational study of 100 PD patients wearing the PKG for ≥ 6 days was performed. It provides a series of data, such as the bradykinesia score (BKS), percent time tremor (PTT), dyskinesia score (DKS), and fluctuation and dyskinesia score (FDS). PKG data and UPDRS scores were analyzed, including UPDRS III total scores, UPDRS III-bradykinesia scores (UPDRS III-B: items 23-26, 31), UPDRS III-rigidity scores (UPDRS III-R: item 22), and scores from the Wearing-off Questionnaire (WOQ-9). This study shows that there was significant correlation between BKS and UPDRS III scores, including UPDRS III total scores, UPDRS III-B, and UPDRS III-R scores (r = 0.479-0.588, p ≤ 0.001), especially in the early-stage group (r = 0.682, p < 0.001). Furthermore, we found that BKS in patients with left-sided onset (33.57 ± 5.14, n = 37) is more serious than in patients with right-sided onset (29.87 ± 6.86, n = 26). Our findings support the feasibility of using the PKG to detect abnormal movements, especially bradykinesia in PD. It is suitable for the early detection, remote monitoring, and timely treatment of PD symptoms.

15.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31840737

RESUMO

The overall survival rate of patients with hepatocellular carcinoma (HCC) has remained unchanged over the last several decades. Therefore, novel drugs and therapies are required for HCC treatment. Isoliquiritigenin (ISL), a natural flavonoid predominantly isolated from the traditional Chinese medicine Glycyrrhizae Radix (Licorice), has a high anticancer potential and broad application value in various cancers. Here, we aimed to investigate the anticancer role of ISL in the HCC cell line Hep3B. Functional analysis revealed that ISL inhibited the proliferation of Hep3B cells by causing G1/S cell cycle arrest in vitro. Meanwhile, the inhibitory effect of ISL on proliferation was also observed in vivo. Further analysis revealed that ISL could suppress the migration and metastasis of Hep3B cells in vitro and in vivo. Mechanistic analysis revealed that ISL inhibited cyclin D1 and up-regulated the proteins P21, P27 that negatively regulate the cell cycle. Furthermore, ISL induced apoptosis while inhibiting cell cycle transition. In addition, phosphatidylinositol 3'-kinase/protein kinase B (PI3K/AKT) signal pathway was suppressed by ISL treatment, and the epithelial marker E-cadherin was up-regulated when the mesenchymal markers Vimentin and N-cadherin were down-regulated. In brief, our findings suggest that ISL could be a promising agent for preventing HCC tumorigenesis and metastasis.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Chalconas/farmacologia , Ciclina D1/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
16.
Curr Neurovasc Res ; 16(2): 107-114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30827240

RESUMO

BACKGROUND: Lacunes and white matter hyperintensities (WMH) are two common findings seen on neuroimaging in patients with cerebral small vessel disease (cSVD). Clinically we observed that some patients with cSVD have aphasia through the language assessment scale. Our study aimed to explore the underlying risk factors for aphasia in cSVD patients. METHODS: This study retrospectively analyzed 38 patients, with and without aphasia, aged 50 or over, Chinese Han population, diagnosed as cSVD with lacunes and/or WMH. We collected demographic characteristics and vascular risk factors. The severity of WMH was assessed by the age related white matter changes (ARWMC) rating scale. RESULTS: Risk factors associated with aphasia were: lower education (p = 0.029), higher total cholesterol (TC) levels (p = 0.023), and higher low-density lipoprotein cholesterol (LDL-C) levels (p = 0.027). After controlling for age and sex, levels of TC (odds ratios, 1.96; 95% confidence interval, 1.06-3.62; p = 0.032) remained associated with aphasia independently. CONCLUSION: High level of TC was significantly associated with a higher risk of aphasia in clinically silent cSVD patients. Early interventions including lipid-lowering treatment, cranial magnetic resonance imaging (MRI) and ARWMC rating scale should be performed. Further studies are needed to explore proper methods of prevention and treatment for aphasia in clinically silent cSVD patients, in addition to understanding the pathophysiological mechanism.


Assuntos
Afasia/etiologia , Encéfalo/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/complicações , Colesterol/sangue , Substância Branca/diagnóstico por imagem , Afasia/sangue , Afasia/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/sangue , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Escolaridade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Estudos Retrospectivos , Fatores de Risco
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