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1.
Front Aging Neurosci ; 13: 755164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721000

RESUMO

Background: Fasudil, a Rho kinase inhibitor, exerts therapeutic effects in a mouse model of Alzheimer's disease (AD), a chronic neurodegenerative disease with progressive loss of memory. However, the mechanisms remain unclear. In addition, the gut microbiota and its metabolites have been implicated in AD. Methods: We examined the effect of fasudil on learning and memory using the Morris water-maze (MWM) test in APPswe/PSEN1dE9 transgenic (APP/PS1) mice (8 months old) treated (i.p.) with fasudil (25 mg/kg/day; ADF) or saline (ADNS) and in age- and gender-matched wild-type (WT) mice. Fecal metagenomics and metabolites were performed to identify novel biomarkers of AD and elucidate the mechanisms of fasudil induced beneficial effects in AD mice. Results: The MWM test showed significant improvement of spatial memory in APP/PS1 mice treated with fasudil as compared to ADNS. The metagenomic analysis revealed the abundance of the dominant phyla in all the three groups, including Bacteroidetes (23.7-44%) and Firmicutes (6.4-26.6%), and the increased relative abundance ratio of Firmicutes/Bacteroidetes in ADNS (59.1%) compared to WT (31.7%). In contrast, the Firmicutes/Bacteroidetes ratio was decreased to the WT level in ADF (32.8%). Lefse analysis of metagenomics identified s_Prevotella_sp_CAG873 as an ADF potential biomarker, while s_Helicobacter_typhlonius and s_Helicobacter_sp_MIT_03-1616 as ADNS potential biomarkers. Metabolite analysis revealed the increment of various metabolites, including glutamate, hypoxanthine, thymine, hexanoyl-CoA, and leukotriene, which were relative to ADNS or ADF microbiota potential biomarkers and mainly involved in the metabolism of nucleotide, lipids and sugars, and the inflammatory pathway. Conclusions: Memory deficit in APP/PS1 mice was correlated with the gut microbiome and metabolite status. Fasudil reversed the abnormal gut microbiota and subsequently regulated the related metabolisms to normal in the AD mice. It is believed that fasudil can be a novel strategy for the treatment of AD via remodeling of the gut microbiota and metabolites. The novel results also provide valuable references for the use of gut microbiota and metabolites as diagnostic biomarkers and/or therapeutic targets in clinical studies of AD.

2.
Mol Neurobiol ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34618332

RESUMO

Macrophage/microglial modulation plays a critical role in the pathogenesis of multiple sclerosis (MS), which is an inflammatory disorder of the central nervous system. Dynamin-related protein 1 is a cytoplasmic molecule that regulates mitochondrial fission. It has been proven that mitochondrial fission inhibitor 1 (Mdivi-1), a small molecule inhibitor of Drp1, can relieve experimental autoimmune encephalomyelitis (EAE), a preclinical animal model of MS. Whether macrophages/microglia are involved in the pathological process of Mdivi-1-treated EAE remains to be determined. Here, we studied the anti-inflammatory effect of Mdivi-1 on mice with oligodendrocyte glycoprotein peptide35-55 (MOG35-55)-induced EAE. We found that Drp1 phosphorylation at serine 616 in macrophages/microglia was decreased with Mdivi-1 treatment, which was accompanied by decreased antigen presentation capacity of the macrophages/microglia in the EAE mouse spinal cord. The Mdivi-1 treatment caused macrophage/microglia to produce low levels of proinflammatory molecules, such as CD16/32, iNOS, and TNF-α, and high levels of anti-inflammatory molecules, such as CD206, IL-10, and Arginase-1, suggesting that Mdivi-1 promoted the macrophage/microglia shift from the inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. Moreover, Mdivi-1 was able to downregulate the expression of TRL2, TRL4, GSK-3ß, and phosphorylated NF-κB-p65 and prevent NF-κB-mediated IL-1ß and IL-6 production. In conclusion, these results indicate that Mdivi-1 significantly alleviates inflammation in mice with EAE by promoting M2 polarization by inhibiting TLR2/4- and GSK3ß-mediated NF-κB activation.

3.
J Neurophysiol ; 126(5): 1756-1771, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34669500

RESUMO

Multiple sclerosis (MS) is an inflammatory, demyelinating, and neurodegenerative disease of the central nervous system (CNS). Here we report the temporal and spatial evolution of various functional neurons during demyelination in a cuprizone (CPZ)-induced mouse model. CPZ did not significantly induce the damage of axons and neurons after 2 wk of feeding. However, after 4-6 wk of CPZ feeding, axons and neurons were markedly reduced in the cortex, posterior thalamic nuclear group, and hippocampus. Simultaneously, the expression of TPH+ tryptophan neurons and VGLUT1+ glutamate neurons was obviously decreased, and the expression of TH+ dopaminergic neurons was slightly decreased in the tail part of the substantia nigra striatum, whereas the number of ChAT+ cholinergic neurons was not significantly different in the brain. In the second week of feeding, CPZ caused a higher level of glutamate secretion and upregulated the expression of EAAT2 on astrocytes, which should contribute to rapid and sufficient glutamate uptake and removal. This finding reveals that astrocyte-driven glutamate reuptake protected the CNS from excitotoxicity by rapid reuptake of glutamate in 4-6 wk of CPZ feeding. At this stage, although NG2+ oligodendroglia progenitor cells (OPCs) were enhanced in the demyelination foci, the myelin sheath was still absent. In conclusion, we comprehensively observed the temporal and spatial evolution of various functional neurons. Our results will assist with understanding how demyelination affects neurons during CPZ-induced demyelination and provide novel information for neuroprotection in myelin regeneration and demyelinating diseases.NEW & NOTEWORTHY Our results further indicate temporal and spatial evolution of various functional neurons during the demyelination in a cuprizone (CPZ)-induced mouse model, which mainly occur 4-6 wk after CPZ feeding. At the same time, the axonal compartment is damaged and, consequently, neuronal death occurs, while glutamate neurons are lost obviously. The astrocyte-mediated glutamate reuptake could protect the neurons from the excitatory effects of glutamate.

4.
Neurochem Res ; 46(12): 3149-3158, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34415495

RESUMO

Hyperoside has a variety of pharmacological activities, including anti-liver injury, anti-depression, anti-inflammatory, and anti-cancer activities. However, the effect of hyperoside on Parkinson's disease (PD) is still unclear. Therefore, we tried to study the therapeutic effect and mechanism of hyperoside on PD in vivo and in vitro models. Rotenone was used to induce PD rat model and SH-SY5Y cell injury model, and hyperoside was used for intervention. Immunohistochemistry, animal behavior assays, TUNEL and Western blot were constructed to observe the protective effect and related mechanisms of hyperoside in vivo. Cell counting kit-8 (CCK-8), flow cytometry, Rh123 staining and Western blot were used for in vitro assays. Rapamycin (RAP) pretreatment was used in rescue experiments to verify the relationship between hyperoside and autophagy in rotenone-induced SH-SY5Y cells. Hyperoside promoted the number of tyrosine hydroxylase (TH)-positive cells, improved the behavioral defects of rats, and inhibited cell apoptosis in vivo. Different concentrations of hyperoside had no significant effect on SH-SY5Y cell viability, but dramatically reversed the rotenone-induced decrease in cell viability, increased apoptosis and loss of cell mitochondrial membrane potential in vitro. Additionally, hyperoside reversed the regulation of rotenone on the Beclin1, LC3II, Bax, cleaved caspase 3, Cyc and Bcl-2 expressions in rat SNpc tissues and SH-SY5Y cells, while promoted the regulation of rotenone on the P62 and α-synuclcin. Furthermore, RAP reversed the effect of hyperoside on rotenone-induced SH-SY5Y cells. Hyperoside may play a neuroprotective effect in rotenone-induced PD rat model and SH-SY5Y cell model by affecting autophagy.

5.
Biol Proced Online ; 23(1): 16, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34433426

RESUMO

BACKGROUND: The Interaction between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein with Angiotensin converting enzyme 2 (ACE2) on the host cells is a crucial step for the viral entry and infection. Therefore, investigating the molecular mechanism underlying the interaction is of great importance for the prevention of the infection of SARS-CoV-2. In this study, we aimed to establish a virus-free in vitro system to study the interaction between the spike protein and host cells of SARS-CoV-2. RESULTS: Our results show that ACE2-overexpressing HEK293T cells are captured by immobilized spike S1 protein, and the cell capturing process can be inhibited by the receptor binding domain of the spike protein or antibodies against S protein. Furthermore, spike S1 protein variant with D614G mutant show a higher cell capturing ability than wild type spike S1 protein and stronger binding capacity of its receptor ACE2. In addition, the captured cells can be eluted as living cells for further investigation. CONCLUSIONS: This study provides a new in vitro system for investigating the interaction between SARS-CoV-2 and host cells and purifying ACE2-expressing cells.

6.
Sleep Med ; 84: 317-323, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34217922

RESUMO

Snoring is the most direct symptom of obstructive sleep apnea hypopnea syndrome (OSAHS) and implies a lot of information about OSAHS symptoms. This paper aimed to identify OSAHS patients by analyzing acoustic features derived from overnight snoring sounds. Mel-frequency cepstral coefficients, 800 Hz power ratio, spectral entropy and other 10 acoustic features were extracted from snores, and Top-6 features were selected from the extracted 10 acoustic features by a feature selection algorithm based on random forest, then 5 kinds of machine learning models were applied to validate the effectiveness of Top-6 features on identifying OSAHS patients. The results showed that when the classification performance and computing efficiency were taken into account, the combination of logistic regression model and Top-6 features performed best and could successfully distinguish OSAHS patients from simple snorers. The proposed method provides a higher accuracy for evaluating OSAHS with lower computational complexity. The method has great potential prospect for the development of a portable sleep snore monitoring device.


Assuntos
Apneia Obstrutiva do Sono , Ronco , Acústica , Humanos , Sono , Apneia Obstrutiva do Sono/diagnóstico , Ronco/diagnóstico , Síndrome
7.
Cancer Cell Int ; 21(1): 329, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193149

RESUMO

BACKGROUND: Patients with nasopharyngeal cancer (NPC) differ in prognosis, even at the same stage; therefore, new biomarkers are urgently required to identify early-stage NPC patients at high risk of poor prognosis. Although Epstein-Barr virus (EBV) DNA has been used for prognosis, the value of many other biomarkers expressed during the infection cycle of EBV remains unclarified. This study aimed to evaluate the prognostic potential of EA-IgA, VCA-IgA and D-dimer in patients with NPC. METHODS: Electronic databases, including PubMed, Embase and Web of Science, were searched up to February 1, 2021. Pooled data were extracted from studies that evaluated the relationship between NPC and overall survival (OS), distant metastasis-free survival (DMFS) or disease-free survival (DFS) and then were subjected to a meta-analysis. RESULTS: Nine studies with 5729 patients were included in this meta-analysis. In patients with NPC, EA-IgA levels significantly predicted OS (HR = 1.63, 95% CI 1.07-2.48). D-Dimer levels significantly predicted OS (HR = 1.75, 95% CI 1.24-2.47) and DMFS (HR = 1.91, 95% CI 1.31-2.79). However, high levels of VCA-IgA were not associated with OS (HR = 1.24, 95% CI 0.95-1.60), DMFS (HR = 1.41, 95% CI 0.92-2.17) or DFS (HR = 2.39, 95% CI 0.78-7.26). CONCLUSIONS: The present findings reveal that EA-IgA and D-dimer, but not VCA-IgA, can be used as prognostic biomarkers in NPC.

8.
Eur Arch Otorhinolaryngol ; 278(12): 4901-4908, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34291347

RESUMO

OBJECTIVE: This study aims to investigate the detection rates, common symptoms and risk factors of gastroesophageal reflux disease (GERD), and laryngopharyngeal reflux disease (LPRD) at the digestive endoscopy center. METHODS: A multicenter cross-sectional survey conducted at three hospitals and a total of 565 eligible participants were enrolled. All the patients completed routine ENT examination, gastroscopy, gastroesophageal reflux questionnaire (GerdQ), reflux symptom index (RSI) and a self-designed 25-item symptoms table survey. RESULTS: Among the 565 eligible participants, the detection rates of GERD and LPRD were 18.41% (104/565) and 9.91% (56/565), respectively. The detection rate of GERD combined with LPRD was 3.19% (18/565). Among GERD and LPRD patients, males (vs. females), middle-aged and elderly patients (vs. young people), BMI ≥ 24.0 kg/m2 (vs. BMI < 24.0 kg/m2), with current smoking history (vs. no smoking), and current drinking history (vs. no drinking), lying down immediately after meal (vs. no lying down immediately after meal) were significantly higher (all p < 0.05). The most common extraesophageal symptoms in patients with GERD were dry mouth (66.35%), globus sensation (56.73%), dry throat and pharyngeal itching (55.77%). The most common extraesophageal symptoms in patients with LPRD were globus sensation (91.07%), dry throat and pharyngeal itching (83.93%), and dry mouth (82.14%). CONCLUSION: GERD and LPRD had a high detection rate at the digestive endoscopy center in Guangzhou, China. Older age, BMI ≥ 24.0 kg/m2, smoking and drinking history were risk factors for both GERD and LPRD. Neither GerdQ nor RSI scores included common extraesophageal symptoms.


Assuntos
Refluxo Laringofaríngeo , Adolescente , Idoso , Estudos Transversais , Feminino , Gastroscopia , Humanos , Hipofaringe , Refluxo Laringofaríngeo/diagnóstico , Refluxo Laringofaríngeo/epidemiologia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
9.
Chem Sci ; 12(22): 7953-7957, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34168849

RESUMO

Aurone-derived azadienes are well-known four-atom synthons for direct [4 + n] cycloadditions owing to their s-cis conformation as well as the thermodynamically favored aromatization nature of these processes. However, distinct from this common reactivity, herein we report an unusual formal migrative annulation with siloxy alkynes initiated by [2 + 2] cycloaddition. Unexpectedly, this process generates benzofuran-fused nitrogen heterocyclic products with formal substituent migration. This observation is rationalized by less common [2 + 2] cycloaddition followed by 4π and 6π electrocyclic events. DFT calculations provided support to the proposed mechanism.

10.
Folia Neuropathol ; 59(1): 32-49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33969676

RESUMO

Alzheimer's disease (AD) is a severe neurodegenerative disorder of the central nervous system (CNS) characterized by neuron loss and dementia. Previous abundant evidence demonstrates that the first critical step in the course of AD is the state of oxidative stress and the neuronal loss is closely related to the interaction of several signalling pathways. The neuroprotective efficacy of Rho-associated protein kinase (ROCK) inhibitor in the treatment of AD has been reported, but its exact mechanism has not been well elucidated. The purpose of this study is to investigate the therapeutic effects of Fasudil on amyloid precursor protein/presenilin-1 (APP/PS1) mice and to discover the potential underlying mechanism. Sixteen 8-month-old APP/PS1 mice were divided into model and Fasudil treatment groups and 8 wild-type mice were used as a normal control group. After the behavioural test, all mice were sacrificed for immunofluorescence and other biochemical tests. The results showed that the administration of Fasudil improved learning and memory ability, elevated the concentration of antioxidative substances and decreased lipid peroxides, as well as inhibited neuronal apoptosis by increasing the expression of B-cell lymphoma-2 (Bcl-2) (p < 0.05), reducing Bcl-2 Associated X (Bax) (p < 0.05) and cleaved caspase-3 (p < 0.05) of APP/PS1 mice. Moreover, Fasudil treatment also ameliorated the phosphorylation of p38 (p < 0.01), c-Jun N-terminal kinase (JNK) (p < 0.001) and extracellular regulated protein kinases (ERK) (p < 0.001), and accelerated the nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) (p < 0.01) expression and its antioxidative downstream molecules (p < 0.05, p < 0.05, and p < 0.05, respectively). Data from the present study demonstrate that Fasudil significantly restored cognitive function, restrained oxidative stress and reduced neuronal apoptosis in the hippocampus, probably by inhibiting ROCK/MAPK and activating Nrf2 signalling pathways in APP/PS1 mice.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Apoptose/efeitos dos fármacos , Cognição/efeitos dos fármacos , Subunidade p45 do Fator de Transcrição NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Quinases Associadas a rho/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide , Animais , Modelos Animais de Doenças , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1
11.
Artigo em Inglês | MEDLINE | ID: mdl-34027599

RESUMO

PURPOSE: Many studies have investigated the prognostic value of tumor-infiltrating lymphocytes (TILs) and tumor-infiltrating macrophages (TIMs) in patients with nasopharyngeal carcinoma (NPC), but the results remain controversial. Here, we performed a meta-analysis to evaluate the prognostic significance of TILs/TIMs in patients with NPC METHODS: The study was registered with PROSPERO (CRD42021234078). PubMed, Embase, and Web of Science databases were searched up to Dec 30, 2020. We reviewed studies that evaluated the relationship between TILs/TIMs and overall survival (OS), disease-free survival (DFS), or progression-free survival (PFS) in NPC. For TILs, CD3, CD4, CD8, and FOXP3 were searched as T-cell markers, CD19 and CD20 as B-cell markers, and CD56 as a natural killer cell marker. For TIMs, CD68 and CD163 were searched as total and M2 macrophage markers, respectively. RESULTS: In total, 19 studies with 3708 NPC were included in this meta-analysis. We found that high total numbers of TILs were significantly associated with favorable OS [hazard ratio (HR) 0.46, 95% confidence interval (CI) 0.38-0.57 and PFS (HR 0.48, 95% CI 0.38-0.62)]. In contrast, tumor infiltration by CD3+ T cells (HR 0.55, 95% CI 0.39-0.76), CD4+ T cells (HR 0.40, 95% CI 0.18-0.85), and CD8+ T cells (HR 0.56, 95% CI 0.34-0.93) correlated positively with OS. No significant relationship was found between survival and tumor infiltration by FOXP3+ T cells, CD68+ macrophages, or CD163+ macrophages. CONCLUSION: Our findings revealed that tumor infiltration by CD3+ , CD4+ , and CD8+ T cells could be prognostic biomarkers in NPC.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34019975

RESUMO

CONTEXT: To provide effective end-of-life care education for health professions students, it is important to understand students' views of death in addition to their perceptions of educational needs and preferences. However, there is a lack of studies addressing interindividual variability in perceptions of end-of-life care educational needs among health professions students. OBJECTIVES: This study aimed to identify latent profiles of perceptions of end-of-life care educational needs among health professions students and examine whether the demographic characteristics, death-related events, death attitude, and death anxiety differed by need subgroup. METHODS: Through convenience sampling, health professions students from three universities in China were recruited between March 2020 and June 2020. Data were collected using a demographic information and death-related experience questionnaire, the End-of-Life Care Curriculum Needs Questionnaire, the End-of-Life Care Educational Needs Questionnaire, the Death Attitudes Profile-Revised, and the Templer's Death Anxiety Scale. RESULTS: A total of 1048 students completed the survey. Two classes of perceptions of end-of-life care educational needs were identified: approximately 29.80% of students belonged to a medium-need group class (1), and 70.20% belonged to a high-need group class (2). Being female and having knowledge of end-of-life care significantly increased the probability of membership in class 2. Students with the two latent profiles reported having varied curriculum needs. In addition, a positive attitude toward death and low death anxiety increased the probability of membership in class 1. CONCLUSION: Two classes of perceptions of end-of-life care educational needs were identified, and these classes were significantly associated with sex and death-related knowledge (P < 0.05). Interindividual variability should be considered in the future development of end-of-care curricula.

13.
Neurosci Lett ; 753: 135880, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33838256

RESUMO

Multiple sclerosis (MS) is mainly associated with the neuroinflammation and demyelination in the central nervous system (CNS), in which the failure of remyelination results in persistent neurological dysfunction. Fasudil, a typical Rho kinase inhibitor, has been exhibited beneficial effects on several models of neurodegenerative disorders. In this study, we showed that Fasudil promoted the uptake of myelin debris by microglia via cell experiments and through a cuprizone (CPZ)-induced demyelinating model. In vitro, microglia with phagocytic debris exhibited enhanced expression of brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF), and the conditioned medium promoted the maturation of oligodendrocyte precursor cells (OPCs). Meanwhile, Fasudil upregulated TREM2/DAP12 pathway, which positively regulated the phagocytosis of myelin debris by microglia. Similarly, in vivo, Fasudil intervention enhanced the clearance of myelin debris, upregulated the expression of BDNF and GDNF on microglia, and promoted the formation of Oligo2+/PDGFRα+ OPCs and the maturation of MBP + oligodendrocytes in the brain. Our results showed that Fasudil targeted the phagocytic function of microglia, effectively clearing myelin debris produced during pathological process possibly by upregulating TREM2/DAP12 pathway, accompanied by increased expression of BDNF and GDNF. However, the precise mechanism underlying the effects of Fasudil in promoting phagocytic effects and neurotrophic factors remains to be elucidated.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Doenças Desmielinizantes/tratamento farmacológico , Bainha de Mielina/efeitos dos fármacos , Remielinização/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Humanos , Masculino , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/patologia , Bainha de Mielina/patologia , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/fisiologia , Fagocitose/efeitos dos fármacos
14.
Science ; 372(6537): 76-80, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33795454

RESUMO

Oxidative dehydrogenation of propane (ODHP) is a key technology for producing propene from shale gas, but conventional metal oxide catalysts are prone to overoxidation to form valueless CO x Boron-based catalysts were recently found to be selective for this reaction, and B-O-B oligomers are generally regarded as active centers. We show here that the isolated boron in a zeolite framework without such oligomers exhibits high activity and selectivity for ODHP, which also hinders full hydrolysis for boron leaching in a humid atmosphere because of the B-O-SiO x linkage, achieving superior durability in a long-period test. Furthermore, we demonstrate an isolated boron with a -B[OH…O(H)-Si]2 structure in borosilicate zeolite as the active center, which enables the activation of oxygen and a carbon-hydrogen bond to catalyze the ODHP.

15.
Research (Wash D C) ; 2021: 9801832, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33693434

RESUMO

Electronic skin (e-skin) with skin-like flexibility and tactile sensation will promote the great advancements in the fields of wearable equipment. Thus, the multifunction and high robustness are two important requirements for sensing capability of the e-skin. Here, a fully organic self-powered e-skin (FOSE-skin) based on the triboelectric nanogenerator (TENG) is developed. FOSE-skin based on TENG can be fully self-healed within 10 hours after being sheared by employing the self-healing polymer as a triboelectric layer and ionic liquid with the temperature sensitivity as an electrode. FOSE-skin based on TENG has the multifunctional and highly robust sensing capability and can sense the pressure and temperature simultaneously. The sensing capability of the FOSE-skin based on TENG can be highly robust with no changes after self-healing. FOSE-skin based on TENG can be employed to detect the arm swing, the temperature change of flowing water, and the motion trajectory. This work provides a new idea for solving the issues of monofunctional and low robust sensing capability for FOSE-skin based on TENG, which can further promote the application of wearable electronics in soft robotics and bionic prosthetics.

16.
Cancer Cell Int ; 21(1): 164, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691680

RESUMO

BACKGROUND: Numerous individual studies have investigated the diagnostic value of EBV-DNA, EA-IgA, VCA-IgA, EBNA1-IgA and Rta-IgG detection for nasopharyngeal carcinoma (NPC), but the conclusions remain controversial. This meta-analysis aimed to determine the value of EBV-DNA, EA-IgA, VCA-IgA, EBNA1-IgA and Rta-IgG detection in the diagnosis of NPC. METHODS: PROSPERO registration number: CRD42019145532. PubMed, EMBASE, Cochrane Library, and Chinese data libraries (Wanfang, CNKI, and CBM) were searched up to January 2019. The pooled sensitivity, specificity, and positive likelihood, negative likelihood, and diagnostic odds ratios were conducted in this meta-analysis. Summary receiver operating characteristic curves evaluated the test-performance global summary. Publication bias was examined by Deek's funnel plot asymmetry test. RESULTS: Forty-seven studies with 8382 NPC patients (NPC group) and 15,089 individuals without NPC (Control group) were included in this meta-analysis. The sensitivity, specificity, positive likelihood (+ LR), negative likelihood (-LR), DOR and AUC of EBV-DNA in diagnosis of NPC were: 0.76 (95% CI 0.73-0.77), 0.96 (95% CI 0.95-0.97), 14.66 (95% CI 9.97-21.55), 0.19 (95% CI 0.13-0.28), 84 (95% CI 50.45-139.88), 0.96 (SE: 0.001), and 0.55 (95% CI 0.54-0.57), 0.96 (95% CI 0.96-0.97), 12.91 (95% CI 9.55-17.45), 0.35 (95% CI 0.29-0.43), 39.57 (95% CI 26.44-59.23), 0.94 (SE: 0.002) for the EA-IgA, and 0.85 (95% CI 0.84-0.85), 0.89 (95% CI 0.88-0.89), 6.73 (95% CI5.38-8.43), 0.17 (95% CI 0.12-0.23), 43.03 (95% CI 31.51-58.76), 0.93 (SE: 0.007) for the VCA-IgA, and 0.86 (95% CI 0.85-0.88), 0.87 (95% CI 0.88-0.90), 7.55 (95% CI 5.79-9.87), 0.16 (95% CI 0.13-0.19), 50.95 (95% CI 34.35-75.57), 0.94 (SE: 0.008) for the EBNA1-IgA, and 0.70 (95% CI 0.69-0.71), 0.94 (95% CI 0.94-0.95), 9.84 (95% CI 8.40-11.54), 0.25 (95% CI 0.21-0.31), 40.59 (95% CI 32.09-51.35), 0.95 (SE: 0.005) for the Rta-IgG. The EBV-DNA had larger AUC compared with other EBV-based antibodies (P < 0.05), while the difference between EA-IgA, VCA-IgA, EBNA1-IgA and Rta-IgG was not statistically significant (P > 0.05). CONCLUSIONS: EBV-DNA, VCA-IgA, EBNA1-IgA and Rta-IgG detection have high accuracy in early diagnosis NPC. In addition, EBV-DNA detection has the higher diagnosis accuracy in NPC. On the other hand, EA-IgA is suitable for the diagnosis but not NPC screening.

17.
Langmuir ; 37(9): 2954-2962, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33636083

RESUMO

Low molecular weight gelators (LMWG) have been extensively explored in many research fields due to their unique reversible gel-sol transformation. Intermolecular interactions between LMWG are known as the main driving force for self-assembly. During this self-assembly process, individually analyzing the contribution difference between various intermolecular interactions is crucial to understand the gel properties. Herein, we report 2,5-bis(hexadecylcarbamoyl)terephthalic acid (BHTA) as a LMWG, which could efficiently form a stable organogel with n-hexadecane, diesel, liquid paraffin, and base lubricant oil at a relatively low concentration. To investigate the contribution difference of intermolecular interactions, we first finished FT-IR spectroscopy and XRD experiments. On the basis of the d-spacing, a crude simulation model was built and then subjected to molecular dynamics (MD) simulations. Then, we knocked out the energy contribution of the H-bonding interactions and π-π stacking, respectively, to evaluate the intermolecular interactions significantly influencing the stability of the gel system. MD simulations results suggest that the self-assembly of the aggregates was mainly driven by dense H-bonding interactions between carbonyl acid and amide moieties of BHTA, which is consistent with FT-IR data. Moreover, wave function analysis at a quantum level suggested these electrostatic interactions located in the middle of the BHTA molecule were surrounded by strong dispersion attraction originating from a hydrophobic environment. Furthermore, we also confirmed that 2 wt % BHTA was able to form gel lubricant with 150BS. The coefficient of friction (COF) data show that the gel lubricant has a better tribological performance than 150BS base lubricant oil. Finally, XPS was performed and offered valuable information about the lubrication mechanism during the friction.

18.
Neural Regen Res ; 16(9): 1702-1710, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33510058

RESUMO

Astrocytes play multifaceted and vital roles in maintaining neurophysiological function of the central nervous system by regulating homeostasis, increasing synaptic plasticity, and sustaining neuroprotective effects. Astrocytes become activated as a result of inflammatory responses during the progression of pathological changes associated with neurodegenerative disorders. Reactive astrocytes (neurotoxic A1 and neuroprotective A2) are triggered during disease progression and pathogenesis due to neuroinflammation and ischemia. However, only a limited body of literature describes morphological and functional changes of astrocytes during the progression of neurodegenerative diseases. The present review investigated the detrimental and beneficial roles of astrocytes in neurodegenerative diseases reported in recent studies, as these cells have promising therapeutic potential and offer new approaches for treatment of neurodegenerative diseases.

19.
Angew Chem Int Ed Engl ; 60(9): 4823-4832, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33205853

RESUMO

The well-known Corey-Bakshi-Shibata (CBS) reduction is a powerful method for the asymmetric synthesis of alcohols from prochiral ketones, often featuring high yields and excellent selectivities. While steric repulsion has been regarded as the key director of the observed high enantioselectivity for many years, we show that London dispersion (LD) interactions are at least as important for enantiodiscrimination. We exemplify this through a combination of detailed computational and experimental studies for a series of modified CBS catalysts equipped with dispersion energy donors (DEDs) in the catalysts and the substrates. Our results demonstrate that attractive LD interactions between the catalyst and the substrate, rather than steric repulsion, determine the selectivity. As a key outcome of our study, we were able to improve the catalyst design for some challenging CBS reductions.

20.
Org Lett ; 23(2): 554-558, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33382271

RESUMO

We report the first organocatalytic kinetic resolution of unactivated aziridines by sulfur nucleophiles with excellent enantioselectivity. A suitable chiral phosphoric acid was found to catalyze the intermolecular ring opening under mild conditions, furnishing a range of highly enantioenriched ß-amino thioethers and aziridines, both of which are useful synthetic building blocks.


Assuntos
Aziridinas/química , Ácidos Fosfóricos/química , Compostos de Sulfidrila/química , Catálise , Cinética , Estrutura Molecular
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