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1.
Cell Prolif ; : e12759, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31922310

RESUMO

OBJECTIVE: Low levels of adiponectin (APN), a biomarker of diabetes mellitus, have been implicated in the poor outcome of intracerebral haemorrhage (ICH). Herein, we aimed to demonstrate the neuroprotective effects of a blood-brain barrier-permeable APN peptide (APNp) on ICH injury in diabetic mice and explore the underlying mechanisms. MATERIALS AND METHODS: Recombinant APNp was administrated intraperitoneally to mice with collagenase-induced ICH. Neurological deficits, brain water content and neural apoptosis were assessed. Western blotting, immunofluorescence staining, quantitative RT-PCR and transmission electron microscopy were used to determine the signalling pathways affected by APNp. RESULTS: Adiponectin peptide significantly alleviated neural apoptosis, neurological deficits and brain oedema following ICH in diabetic mice. Mechanistically, APNp promoted the restoration of peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α related mitochondrial function and suppressed activating transcription factor 4 (ATF4)-CCAAT-enhancer-binding protein homologous protein (CHOP)-induced neural apoptosis. Furthermore, Smad3 signalling was found to play a regulatory role in this process by transcriptionally regulating the expression of PGC-1α and ATF4. APNp significantly suppressed the elevated phosphorylation and nuclear translocation of Smad3 after ICH in diabetic mice, while the protective effects of APNp on mitochondrial and ATF4-CHOP apoptosis pathways were counteracted when Smad3 was activated by exogenous transforming growth factor (TGF)-ß1 treatment. CONCLUSIONS: Our study provided the first evidence that APNp promoted neural survival following ICH injury in the diabetic setting and revealed a novel mechanism by which APNp suppressed mitochondrial and ATF4-CHOP apoptosis pathways in a Smad3 dependent manner.

2.
Biotechnol Prog ; : e2957, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31912987

RESUMO

We propose an integrated structural approach to search potential aptamer molecules for targeting cancer receptor proteins. We used the outer cellular domain of the B-lymphocyte antigen, CD19, as the target for this study. First, using available protein-aptamer structures deposited in the protein data bank as resources, structural annotation was performed to seek the most probable binding aptamer and its potential initial configuration to the CD19 structure. Using this initial structure, molecular dynamics (MD) simulations were performed for adjustment of the aptamer-binding. During this process, we observed an "aptamer walking" mechanism of the binding of the single-stranded RNA-aptamer to CD19: the aptamer molecule gradually adjusts its configurations and shifts toward favorable binding positions. However, the target molecule CD19 maintained a relatively stable conformation during this process. The interface area between the RNA-aptamer and CD19 increased from less than 8 nm2 to over 12 nm2 during a 2-µs MD simulation. Using a stable binding pose as the starting structure, we manually mutated the RNA-aptamer to a DNA-aptamer and found that the interface area was further increased to over 16 nm2 , indicating a stronger affinity compared to the RNA-aptamer. The RNA- and DNA-aptamers and their stable binding-poses to the CD19 molecule may be used as templates in designing potential aptamer molecules that target the B-cell marker molecule CD19 with enhanced specificity and stability.

3.
Transl Stroke Res ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902083

RESUMO

Intracerebral hemorrhage (ICH) is a life-threatening subtype of cerebral stroke with high morbidity and mortality; however, effective treatment for ICH is still lacking. Adiponectin (APN) is a a kind of fat-derived plasma protein with beneficial effects in cerebrovascular disorders. In this study, we aimed to investigate the protective effects of recombinant APN peptide (APNp) on brain injury after ICH in adult male C57BL/6J mice and further explored the underlying molecular mechanisms of these effects. APNp treatment exerted dose-dependent neuroprotective effects including improved neurological function, decreased brain edema, reduced neural apoptosis, and alleviated blood-brain barrier (BBB) disruption in ICH mice. We found the massive accumulation of APNp on reactive astrocytes around brain microvessels under hemorrhage conditions by immunofluorescence analysis. mRNA sequencing (mRNA-seq) and transcriptome analysis indicated that APNp significantly attenuated the inflammatory response and mitochondrial respiratory dysfunction in astrocytes. Further study revealed that this process was, at least in part, reliant on the inhibition of Drp1-mediated excessive mitochondrial fission. More specifically, APNp increased AMP-activated protein kinase (AMPK) activation-dependent Drp1 serine 637 (S637) phosphorylation, which inhibited the translocation of Drp1 to the mitochondrial membrane and reduced mitochondrial fragmentation and the production of mitochondrial superoxide, ultimately attenuating inflammatory brain injury induced by hemorrhage. In conclusion, we propose APNp as a potential therapeutic agent for ICH. We provide the first mechanistic evidence that APNp can modulate Drp1-mediated mitochondrial fission, which then contributes to alleviating astrocyte-derived inflammation.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31940543

RESUMO

OBJECTIVE: Most BCI (brain-computer interface) studies have focused on detecting motion intention from a resting state. However, the dynamic regulation of two motion states, which usually happens in real life, is rarely studied. Besides, popular within-subject methods also require an extensive and time-consuming learning stage when testing on a new subject. This paper proposed a method to discriminate dynamic gait-adjustment intention with strong adaptability for different subjects. METHODS: Cerebral hemoglobin signals obtained from 30 subjects were studied to decode gait-adjustment intention. Cerebral hemoglobin information was recorded by using fNIRS (functional near infrared spectroscopy) technology. Mathematical morphology filtering was applied to remove zero drift and EWM (Entropy Weight Method) was used to calculate the average hemoglobin values over Regions of Interest (ROIs). The gradient boosting decision tree (GBDT) was utilized to detect the onset of self-regulated intention. A 2-layer-GA-SVM (Genetic Algorithm-Support Vector Machine) model based on stacking algorithm was further proposed to identify the four types of self-regulated intention (speed increase, speed reduction, step increase, and step reduction). RESULTS: It was found that GBDT had a good performance to detect the onset intention with an average AUC (Area Under Curve) of 0.894. The 2-layer-GA-SVM model boosted the average ACC (accuracy) of four types of intention from 70.6% to 84.4% (p=0.005) from the single GA-SVM model. Furthermore, the proposed method passed pseudo-online test with the average results as following: AUC = 0.883, TPR (True Positive Rate) = 97.5%, FPR (False Positive Rate) = 0.11%, and LAY (Detection Latency) = -0.52 ± 2.57 seconds for the recognition of gait-adjustment intention; ACC = 80% for the recognition of adjusted gait. CONCLUSION: The results indicate that it is feasible to decode dynamic gait-adjustment intentions from a motion state for different subjects based on fNIRS technology. It has a potential to realize the practical application of fNIRS-based brain-computer interface technology in controlling walking-assistive devices.

7.
Neurosci Lett ; 718: 134745, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923521

RESUMO

BACKGROUND: Most studies assessing brain-personality mechanisms have used Western personality questionnaires. However, Western personality questionnaires may not objectively reflect the personality characteristics of individuals in Eastern cultures such as China. Hence, we adopted the functional magnetic resonance imaging (fMRI) and the Chinese localized scale, FPPI, to explore the brain mechanisms differences of typical yin and typical yang personalities of individuals in China. METHODS: 30 typical yin personality participants (TYI) and 34 typical yang personality participants (TYA) were enrolled according to the FPPI. The group differences of the functional brain networks among 90 specific brain regions were mapped using fMRI data and then analyzed by the conventional network metrics (CNM) and frequency subgraph mining (FSM). RESULTS: The CNM and FSM differences between two typical personality groups were traced to the frontal, temporal, and parietal cortices. The yin group, reflecting the rich emotions and feelings of individuals, showed higher betweenness centrality (BCi) and nodal efficiency (Ei) values in putamen and middle frontal gyrus. The yang group, reflecting active behaviors and tendency to adapting to the changing surroundings, showed higher BCi and Ei values in precuneus, posterior cingulate gyrus, and inferior parietal lobule, brain areas in the default mode network (DMN). CONCLUSION: These results supplied evidence for the neurobiological differences between typical yin and typical yang personality participants based on Chinese culture. These results also provide a new perspective to help researchers understand brain mechanism differences between yin and yang personality groups in the Chinese culture.

8.
Periodontol 2000 ; 82(1): 173-185, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31850634

RESUMO

The effects of probiotic supplementation on systemic health and gastrointestinal diseases have been investigated in numerous studies. The aim of this review is to provide an overview of probiotics and their effects on periodontal health. Probiotics show beneficial effects as adjunctive therapeutics and as stand-alone agents in the treatment and prevention of gingivitis as well as specific clinical parameters of periodontitis. This review focuses on the clinical and microbiological aspects of probiotics in the context of health, gingivitis, and periodontitis. In addition, a special focus on nisin-producing probiotics and nisin itself showcase their significant potential for oral and systemic use.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31815969

RESUMO

The peri-implant soft tissue seal consists of a connective tissue cuff and a junctional epithelium that is different from the arrangement of periodontium around a natural tooth. However, the peri-implant soft tissue complex lacks Sharpey's fibers, thus offering less resistance to clinical probing and biofilm penetration compared to the natural dentition. Therefore, the proper restorative emergence profile design is essential to facilitate favorable esthetic outcomes and maintain peri-implant health. The aim of this article is to review the currently available evidence related to the design of subgingival (critical and subcritical) and supragingival contours of the implant restorative emergence profile (IREP) as well as provide a flowchart for decision-making in clinical practice. Theoretically, the subgingival contours of the crown/abutment complex should mimic the morphology of the root and the cervical third of the anatomic crown as much and as often as possible. However, this is highly dependent upon the three-dimensional spatial position of the implant relative to the hard and soft tissue complex, in addition to the location of the definitive restoration. Frequently, a convex critical contour is required on the facial aspect of a palatally or incisally positioned implant to support an adequate gingival-margin architecture. Conversely, if the implant is placed too far facially, then a flat or concave contour is recommended. In instances where soft tissue support is not needed, the subcritical area may be undercontoured to increase the thickness, height, and stability of the soft tissue cuff.

10.
Cancer Commun (Lond) ; 39(1): 81, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796105

RESUMO

BACKGROUND: High-grade glioma (HGG) is a fatal human cancer. Bortezomib, a proteasome inhibitor, has been approved for the treatment of multiple myeloma but its use in glioma awaits further investigation. This study aimed to explore the chemotherapeutic effect and the underlying mechanism of bortezomib on gliomas. METHODS: U251 and U87 cell viability and proliferation were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, tumor cell spheroid growth, and colony formation assay. Cell apoptosis and cell cycle were detected by flow cytometry. Temozolomide (TMZ)-insensitive cell lines were induced by long-term TMZ treatment, and cells with stem cell characteristics were enriched with stem cell culture medium. The mRNA levels of interested genes were measured via reverse transcription-quantitative polymerase chain reaction, and protein levels were determined via Western blotting/immunofluorescent staining in cell lines and immunohistochemical staining in paraffin-embedded sections. Via inoculating U87 cells subcutaneously, glioma xenograft models in nude mice were established for drug experiments. Patient survival data were analyzed using the Kaplan-Meier method. RESULTS: Bortezomib inhibited the viability and proliferation of U251 and U87 cells in a dose- and time-dependent manner by inducing apoptosis and cell cycle arrest. Bortezomib also significantly inhibited the spheroid growth, colony formation, and stem-like cell proliferation of U251 and U87 cells. When administrated in combination, bortezomib showed synergistic effect with TMZ in vitro and sensitized glioma to TMZ treatment both in vitro and in vivo. Bortezomib reduced both the mRNA and protein levels of Forkhead Box M1 (FOXM1) and its target gene Survivin. The FOXM1-Survivin axis was markedly up-regulated in established TMZ-insensitive glioma cell lines and HGG patients. Expression levels of FOXM1 and Survivin were positively correlated with each other and both related to poor prognosis in glioma patients. CONCLUSIONS: Bortezomib was found to inhibit glioma growth and improved TMZ chemotherapy efficacy, probably via down-regulating the FOXM1-Survivin axis. Bortezomib might be a promising agent for treating malignant glioma, alone or in combination with TMZ.

11.
Chem Commun (Camb) ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31854403

RESUMO

A new type of supramolecular polymeric material was constructed efficiently via orthogonal pillar[5]arene-based host-guest and hydrogen bond interactions. The supramolecular polymeric materials prove to be a good catalyst for the Fenton reaction in water.

12.
Huan Jing Ke Xue ; 40(10): 4395-4403, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854806

RESUMO

Based on the demand for a volatile organic compounds (VOCs) emissions inventory for Beijing and for the reduction in VOC emissions, the three major solvent-based industries of automobile manufacturing, furniture manufacturing, and publication printing were selected for this study. In each case, emissions link negative pressure sampling was used in combination with laboratory-based GC-MS/FID to obtain the VOC spectra. The results show that there are significant differences in the emission of VOCs from the main stages of automobile manufacturing. Specifically, the paint-coating process was dominated by the emission of oxygenated VOCs and aromatic hydrocarbons, accounting for 71.26% and 27.14% of total VOC emissions, respectively. The proportion of aromatic hydrocarbons emitted during the varnishing process was very large (84.10%), which were mainly composed of the benzene series. The differences in VOC emissions during different stages of the furniture manufacturing process were small, mainly consisting of oxygenated VOCs and aromatic hydrocarbons, which accounted for 55.08% and 18.98% of the total, respectively. Of these, alcohols and esters were the main components. VOCs emitted from different stages of the publication printing process could not be monitored separately. Thus, the VOCs in the mixed exhaust gas from this process were mainly composed of alkanes and oxygenated VOCs, which accounted for 47.29% and 44.57% of the total emissions, respectively.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31861894

RESUMO

Examining the drivers of landscape ecological risk can provide scientific information for planning and landscape optimization. The landscapes of the Amu Darya Delta (ADD) have recently undergone great changes, leading to increases in landscape ecological risks. However, the relationships between landscape ecological risk and its driving factors are poorly understood. In this study, the ADD was selected to construct landscape ecological risk index (ERI) values for 2000 and 2015. Based on a geographically weighted regression (GWR) model, the relationship between each of the normalized difference vegetation index (NDVI), land surface temperature (LST), digital elevation model (DEM), crop yield, population density (POP), and road density and the spatiotemporal variation in ERI were explored. The results showed that the ERI decreased from the periphery of the ADD to the centre and that high-risk areas were distributed in the ADD's downstream region, with the total area of high-risk areas increasing by 86.55% from 2000 to 2015. The ERI was spatially correlated with Moran's I in 2000 and 2015, with correlation of 0.67 and 0.72, respectively. The GWR model indicated that in most ADD areas, the NDVI had a negative impact on the ERI, whereas LST and DEM had positive impacts on the ERI. Crop yield, road density and POP were positively correlated with the ERI in the central region of the ADD, at road nodes and in densely populated urban areas, respectively. Based on the findings of this study, we suggest that the ecological constraints of the aforementioned factors should be considered in the process of delta development and protection.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31845448

RESUMO

We reported herein a rare artificial system on substrate-induced dimerization assembly of chiral macrocycle catalysts, enabling a highly cooperative hydrogen-bonding activation network for efficient and enantioselective transformation. These macrocycles contain two thiourea and two chiral diamine moieties and were found to dimerize with sulfate to form a sandwich-like assembly. Upon dimerization, the macrocycles adopt an extended conformation and reciprocally complement the hydrogen-bonding interaction sites. Inspired by the guest-induced dynamic assembly, these macrocycles were applied on catalyzing decarboxylative Mannich reaction of cyclic aldimines containing a sulfamate heading group. As anticipated, the imine substrate can be activated toward nucleophilic attack of ß-ketoacid through a highly cooperative hydrogen-bonding network enabled by sulfamate-induced dimerization assembly of the macrocycle catalysts. By this strategy, highly efficient (>95% yield in most cases) and enantioselective (up to 97.5:2.5 er) transformation of a variety of substrates using only 5 mol% macrocycle was achieved, providing a potent means for organocatalytic asymmetric transformation of the titled reactions.

15.
J Hazard Mater ; 386: 121882, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31884369

RESUMO

For decades, pesticides have been widely used for controlling pests and protecting crops around the world, and the food safety issues caused by these compounds have raised widespread concern. However, the different enantioselective behaviors and biological activities of chiral pesticide enantiomers are often ignored. In this work, a novel method was put forward to investigate the enantioselective effects and potential risks of two paclobutrazol enantiomers during cucumber pickling process. The degradation kinetics indicated that when paclobutrazol reside in cucumber and was introduced into the pickling process, the half-time of paclobutrazol isomers were significantly different (9.24 d and 16.6 d), and the conversion phenomenon between the two enantiomers could also be observed. In addition, results from 16S rRNA and ITS sequencing shown that (2R, 3R)-paclobutrazol and (2S, 3S)-paclobutrazol have an obviously enantiomeric effects on microbial community of pickling system and the degradation of paclobutrazol was probably attributed to the presence of Pseudomonas and Serratia. Finally, the microorganisms functions were found to be disrupted under the exposure of (2R, 3R)-paclobutrazol and metabolic function of microorganisms to xenobiotic was inhibited, which might cause potential risks to the quality of preserved foods. In summary, we have devised a method and provided a novel insight into the potential risks of chiral pesticide residues on food safety and human health.

16.
J Periodontol ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670835

RESUMO

BACKGROUND: This systematic review endeavored to investigate the effect of soft tissue phenotype modification therapy (PhMT-s) at sites with a tooth or an implant supported fixed dental prosthesis. METHODS: A comprehensive literature search was conducted by two independent examiners to identify relevant studies reporting differences in clinical, esthetic, or radiographic outcomes of interest between sites underwent PhMT-s and sites that remained untreated. Risk of bias assessment was calculated for all included studies. Meta-analyses involving endpoints of interest were performed when feasible. RESULTS: No controlled studies pertaining to tooth sites were identified. A total of six articles reporting on the outcomes of buccal soft tissue phenotype modification around implants were selected, of which, five were included in the meta-analyses. Quantitative analyses showed a weighted mean difference (WMD) of 0.98 mm (95% CI = 0.25 to 1.72 mm, P = 0.009) for change of tissue thickness; a WMD of -4.87% (95% CI = -34.27 to 24.53%, P = 0.75) for bleeding on probing (BOP); a WMD of 0.36 mm (95% CI = 0.12 to 0.59 mm, P = 0.003) for mucosal recession (MR); a WMD of 0.13 mm (95% CI = -0.11 to 0.36 mm, P = 0.30 for probing depth (PD); a WMD of 1.08 (95% CI = -0.39 to 2.55, P = 0.15) for pink esthetic score (PES), and a WMD of 0.40 mm (95% CI = -0.34 to 1.14 mm, P = 0.28) for marginal bone loss (MBL). CONCLUSIONS: Surgical modification of peri-implant soft tissue phenotype via PhMT-s may decrease the amount of MR. Future clinical trials are needed to warrant the clinical benefits of modifying soft tissue phenotype around tooth-supported restorations.

17.
Front Immunol ; 10: 2408, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681297

RESUMO

Astrocyte-mediated inflammation and oxidative stress elicit cerebral ischemia-reperfusion (IR) injury after stroke. Nuclear factor (NF)-κB activates astrocytes and generates pro-inflammatory factors. The purpose of the present study is to elucidate the effect of pterostilbene (PTE, a natural stilbene) on astrocytic inflammation and neuronal oxidative injury following cerebral ischemia-reperfusion injury. A middle cerebral artery occlusion-reperfusion (MCAO/R) mouse model and HT22/U251 co-culture model subjected to oxygen-glucose deprivation and re-introduction (OGD/R) were employed, with or without PTE treatment. The data showed that PTE delivery immediately after reperfusion, at 1 h after occlusion, decreased infarct volume, brain edema, and neuronal apoptosis and improved long-term neurological function. PTE decreased oxidation (i.e., production of reactive oxygen species, malondialdehyde) and inflammatory mediators (tumor necrosis factor-α, interleukin-1ß, and interleukin-6) and increased anti-oxidative enzyme activities (i.e., of superoxide dismutase, glutathione peroxidase), by inhibiting phosphorylation and nuclear translocation of NF-κB. In conclusion, PTE attenuated astrocyte-mediated inflammation and oxidative injury following IR via NF-κB inhibition. Overall, PTE is a promising neuroprotective agent.

18.
Front Chem ; 7: 689, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681734

RESUMO

In this paper, we report a facile one-step hydrothermal method to synthesize tetragonal Na3V2(PO4)2F3@C particles which are connected by carbon nanotubes (CNTs) networks, using water as hydrothermal solvents. In this strategy, the reduction and crystallization of materials are carried out in the hydrothermal process (180°C, 12 h), no additional heat treatment is required. The well-crystallized Na3V2(PO4)2F3 tetragonal grains (5-10 µm) are coated with amorphous nano-carbon and connected by highly conductive CNTs. The addition of CNTs can not only improve the conductivity of materials but also effectively inhibit the Na3V2(PO4)2F3 grains over growth. The Na3V2(PO4)2F3@C/CNTs composite possesses very flat charge/discharge platforms of 3.6 and 4.1 V. The sample exhibits an initial discharge specific capacity of 120.2 and 74.3 mAh g-1 at 0.1 and 10 C rate, respectively, and shows excellent cyclical stability. The composite owns excellent electrochemical performances owing to the three-dimensional highly conductive network which is co-constructed by the CNTs and nano-carbon coating layer.

19.
Chaos ; 29(11): 113114, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31779363

RESUMO

Cooperation is an effective manner to enable different elements of complex networks to work well. In this work, we propose a coevolution mechanism of learning willingness in the network population: an agent will be more likely to imitate a given neighbor's strategy if her payoff is not less than the average performance of all her neighbors. Interestingly, increase of learning willingness will greatly promote cooperation even under the environment of extremely beneficial temptation to defectors. Through a microscopic analysis, it is unveiled that cooperators are protected due to the appearance of large-size clusters. Pair approximation theory also validates all these findings. Such an adaptive mechanism thus provides a feasible solution to relieve social dilemmas and will inspire further studies.

20.
Rev Sci Instrum ; 90(11): 114712, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779373

RESUMO

A flexible mechanical deformation test system, which is a combination of the microwave and the flexible film, is proposed. The system consists of a U-shaped microwave resonator, coaxial transmission line, and PDMS flexible substrate. Microwave signals are generated from the vector network analyzer and loaded to the coaxial transmission line and then coupled to the U-shaped resonator through the coupling loop. The resonator works at the gigahertz band with the test range from 3 GHz to 40 GHz. The resonant frequency of the resonator can be adjusted by changing the shape of PDMS, and the related signals can be detected by using the S11 parameter of the microwave. The response time of the U-shaped resonator is less than 20 ms, and the sensitivity on the curved surface is 12.5 Hz/nm.

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