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Photocatalytic overall water splitting with two-dimensional materials is a promising strategy to solve the problems of environmental pollution and energy shortage. However, conventional photocatalysts are often limited to a narrow visible photo-absorption range, low catalytic activity, and poor charge separation. Herein, given the intrinsic polarization facilitating the improvement of photogenerated carrier separation, we adopt a polarized g-C3N5 material combining the doping strategy to alleviate the abovementioned problems. Boron (B), as a Lewis acid, has a great chance to improve the capture and catalytic activity of water. By doping B into g-C3N5, the overpotential for the complicated four-electron process of the oxygen reduction reaction is only 0.50 V. Simultaneously, the B doping-induced impurity state effectively reduces the band gap and broadens the photo-absorption range. Moreover, with the increase of B doping concentration, the photo-absorption range and catalytic activity can be gradually improved. Whereas when the concentration exceeds 33.3%, the reduction potential of the conduction band edge will not meet the demand for hydrogen evolution. Therefore, excessive doping is not recommended in experiments. Our work affords not only a promising photocatalyst but also a practical design scheme by combining polarizing materials and the doping strategy for overall water splitting.
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Titanium and titanium alloy with low density, high specific strength, good biological, excellent mechanical compatibility and easy to process have been widely used in the medical materials, but their application in orthopedics and dentistry often face bacterial infection, corrosion failure and stress shielding. In this paper, Ti-15Mo-7Cu (TM-7Cu) alloy was prepared by high vacuum non-consumable electric arc melting furnace and then treated by solution and aging treatment. The microstructure, mechanical properties, antibacterial properties and cytocompatibility were studied by X-ray diffraction, microhardness tester, electrochemical working station, antibacterial test and Live/Dead staining technology. The results have shown that the heat treatment significantly influenced the phase transformation, the precipitation of Ti2Cu phase, the elastic modulus and the antibacterial ability. With the extension of the aging time, the elastic modulus slightly increased and the antibacterial rate obviously increased. TM-7Cu alloy with a low elastic modulus of 83GPa and a high antibacterial rate of > 93% was obtained. TM-7Cu alloy showed no cytotoxicity to MC3T3. It was suggested that TM-7Cu might be a highly competitive medical material.
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Ligas , Titânio , Módulo de Elasticidade , Estudos de Viabilidade , Titânio/farmacologia , Ligas/farmacologia , Antibacterianos/farmacologiaRESUMO
Glycerol is seen in biological systems as an intermediate in lipid metabolism. In recent years, glycerol has been reported to act as a chemical chaperone to correct the conformation of proteins. Here, we investigate the role of glycerol in galectin-7 (Gal-7). The thermal shift and CD assays showed that the thermal stability of Gal-7 increased with glycerol concentration but with little secondary structure changes induced by glycerol. In addition, glycerol can inhibit Gal-7-mediated erythrocyte agglutination. We also solved the crystal structures of human Gal-7 in complex with glycerol in two different conditions. Glycerol binds at the carbohydrate-recognition binding sites of Gal-7, which indicates glycerol as a small ligand for Gal-7. Surprisingly, glycerol can bind a new pocket near the N-terminus of Gal-7, which can greatly reduce the flexibility and improve the stability of this region. Moreover, overexpression of Gal-7 decreased the intracellular triglyceride levels and increased mRNA expression of aquaporin-3 (AQP-3) when HeLa cells were incubated with glycerol. These findings indicate that Gal-7 might regulate glycerol metabolism. Overall, our results on human Gal-7 raise the perspective to systematically explore this so far unrecognized phenomenon for Gal-7 in glycerol metabolism.
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Aquaporinas , Glicerol , Humanos , Glicerol/farmacologia , Ligantes , Células HeLa , Galectinas/metabolismo , Carboidratos/química , Triglicerídeos , RNA MensageiroRESUMO
To understand the pathogenesis of specific neuronal circuit dysfunction in Alzheimer's disease (AD), we investigated the fate of three subclasses of "modulatory interneurons" in hippocampal CA1 using the AppNL-F/NL-F knock-in mouse model of AD. Cholecystokinin- and somatostatin-expressing interneurons were aberrantly hyperactive preceding the presence of the typical AD hallmarks: neuroinflammation and amyloid-ß (Aß) accumulation. These interneurons showed an age-dependent vulnerability to Aß penetration and a reduction in density and coexpression of the inhibitory neurotransmitter GABA synthesis enzyme, glutamic acid decarboxylase 67 (GAD67), suggesting a loss in their inhibitory function. However, calretinin (CR) interneurons-specialized to govern only inhibition, showed resilience to Aß accumulation, preservation of structure, and displayed synaptic hyperinhibition, despite the lack of inhibitory control of CA1 excitatory pyramidal cells from midstages of the disease. This aberrant inhibitory homeostasis observed in CA1 CR cells and pyramidal cells was "normalized" by blocking P2Y1 purinoreceptors, which were "upregulated" and strongly expressed in CR cells and astrocytes in AppNL-F/NL-F mice in the later stages of AD. In summary, AD-associated cell-type selective destruction of inhibitory interneurons and disrupted inhibitory homeostasis rectified by modulation of the upregulated purinoreceptor system may serve as a novel therapeutic strategy to normalize selective dysfunctional synaptic homeostasis during pathogenesis of AD.
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Doença de Alzheimer/fisiopatologia , Região CA1 Hipocampal/fisiopatologia , Calbindina 2/fisiologia , Interneurônios/fisiologia , Inibição Neural , Receptores Purinérgicos P2Y1/fisiologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Região CA1 Hipocampal/patologia , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Interneurônios/patologia , Masculino , Camundongos Endogâmicos C57BL , Regulação para CimaRESUMO
Synaptic dysfunction is widely proposed as an initial insult leading to the neurodegeneration observed in Alzheimer's disease (AD). We hypothesize that the initial insult originates in the lateral entorhinal cortex (LEC) due to deficits in key interneuronal functions and synaptic signaling mechanisms, in particular, Wnt (Wingless/integrated). To investigate this hypothesis, we utilized the first knock-in mouse model of AD (AppNL-F/NL-F), expressing a mutant form of human amyloid-ß (Aß) precursor protein. This model shows an age-dependent accumulation of Aß, neuroinflammation, and neurodegeneration. Prior to the typical AD pathology, we showed a decrease in canonical Wnt signaling activity first affecting the LEC in combination with synaptic hyperexcitation and severely disrupted excitatory-inhibitory inputs onto principal cells. This synaptic imbalance was consistent with a reduction in the number of parvalbumin-containing (PV) interneurons, and a reduction in the somatic inhibitory axon terminals in the LEC compared with other cortical regions. However, targeting GABAA receptors on PV cells using allosteric modulators, diazepam, zolpidem, or a nonbenzodiazepine, L-838,417 (modulator of α2/3 subunit-containing GABAA receptors), restored the excitatory-inhibitory imbalance observed at principal cells in the LEC. These data support our hypothesis, providing a rationale for targeting the synaptic imbalance in the LEC for early stage therapeutic intervention to prevent neurodegeneration in AD.
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Doença de Alzheimer/fisiopatologia , Córtex Entorrinal/fisiopatologia , Neurônios/fisiologia , Sinapses/fisiologia , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Córtex Entorrinal/patologia , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural/fisiologia , Neurônios/patologia , Receptores de GABA-A/metabolismo , Sinapses/patologia , Técnicas de Cultura de Tecidos , Via de Sinalização WntRESUMO
Autographa californica multiple nucleopolyhedrovirus (AcMNPV) orf75 (ac75) is a highly conserved gene of unknown function. In this study, we constructed an ac75 knockout AcMNPV bacmid and investigated the role of ac75 in the baculovirus life cycle. The expression and distribution of the Ac75 protein were characterized, and its interaction with another viral protein was analyzed to further understand its function. Our data indicated that ac75 was required for the nuclear egress of nucleocapsids, intranuclear microvesicle formation, and subsequent budded virion (BV) formation, as well as occlusion-derived virion (ODV) envelopment and embedding of ODVs into polyhedra. Western blot analyses showed that two forms, of 18 and 15 kDa, of FLAG-tagged Ac75 protein were detected. Ac75 was associated with both nucleocapsid and envelope fractions of BVs but with only the nucleocapsid fraction of ODVs; the 18-kDa form was associated with only BVs, whereas the 15-kDa form was associated with both types of virion. Ac75 was localized predominantly in the intranuclear ring zone during infection and exhibited a nuclear rim distribution during the early phase of infection. A phase separation assay suggested that Ac75 was not an integral membrane protein. A coimmunoprecipitation assay revealed an interaction between Ac75 and the integral membrane protein Ac76, and bimolecular fluorescence complementation assays identified the sites of the interaction within the cytoplasm and at the nuclear membrane and ring zone in AcMNPV-infected cells. Our results have identified ac75 as a second gene that is required for both the nuclear egress of nucleocapsids and the formation of intranuclear microvesicles.IMPORTANCE During the baculovirus life cycle, the morphogenesis of both budded virions (BVs) and occlusion-derived virions (ODVs) is proposed to involve a budding process at the nuclear membrane, which occurs while nucleocapsids egress from the nucleus or when intranuclear microvesicles are produced. However, the exact mechanism of virion morphogenesis remains unknown. In this study, we identified ac75 as a second gene, in addition to ac93, that is essential for the nuclear egress of nucleocapsids, intranuclear microvesicle formation, and subsequent BV formation, as well as ODV envelopment and embedding of ODVs into polyhedra. Ac75 is not an integral membrane protein. However, it interacts with an integral membrane protein (Ac76) and is associated with the nuclear membrane. These data enhance our understanding of the commonalities between nuclear egress of nucleocapsids and intranuclear microvesicle formation and may help to reveal insights into the mechanism of baculovirus virion morphogenesis.
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Núcleo Celular/virologia , Proteínas do Nucleocapsídeo/fisiologia , Nucleopoliedrovírus/fisiologia , Replicação Viral , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/ultraestrutura , Técnicas de Inativação de Genes , Microscopia Eletrônica , Membrana Nuclear/metabolismo , Proteínas do Nucleocapsídeo/genética , Células Sf9 , SpodopteraRESUMO
In this article, a supersandwich-type electrochemical biosensor for sequence-specific DNA detection is described. In design, single-strand DNA labeled with methylene blue (MB) was used as signal probe, and auxiliary probe was designed to hybridize with two different regions of signal probe. The biosensor construction contained three steps: (i) capture DNA labeled with thiol was immobilized on the surface of gold nanoparticles decorated reduced graphene oxide (Au NPs/rGO); (ii) the sandwich structure formation contained "capture-target-signal probe"; and (iii) auxiliary probe was introduced to produce long concatamers containing signal molecule MB. Differential pulse voltammetry (DPV) was used to monitor the DNA hybridization event using peak current changes of MB in phosphate-buffered saline (PBS) containing 1.0M NaClO4. Under optimal conditions, the peak currents of MB were linear with the logarithm of the concentration of target DNA in the range of 0.1µM to 0.1fM with a detection limit of 35aM (signal/noise=3). In addition, this biosensor exhibited good selectivity even for single-base mismatched target DNA detection.
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Técnicas Biossensoriais , DNA/análise , Técnicas Eletroquímicas , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Óxidos/químicaRESUMO
In this study, an ultra-sensitive hairpin DNA-based electrochemical DNA biosensor for K-ras gene detection is described. Gold nanoparticles (Au-NPs) and horseradish peroxidase (HRP)-streptavidin capped Au-NPs (HAS) conjugates are used for signal amplification. Initially, hairpin DNA dually labeled with thiol at its 5' end and with biotin at its 3' end is immobilized on the surface of Au-NPs modified electrode, and the hairpin DNA is in a "closed" state; hence, the HAS conjugates are shielded from being approached by the biotin due to steric hindrance. However, in the presence of target DNA, the target DNA hybridizes with the loop structure of hairpin DNA and causes conformational change, resulting in biotin forced away from the electrode surface, thereby becoming accessible for the HAS conjugates. Thus, the HAS conjugates are linked to the electrode surface via the specific interaction between biotin and streptavidin. Electrochemical detection was performed in phosphate-buffered saline (PBS) containing tetramethylbenzidine (TMB) and H2O2. Under optimal conditions, the peak current differences (ΔI) are linear with the target DNA in the range from 0.1 fM to 1 nM with a detection limit of 0.035 fM. Furthermore, this biosensor also demonstrates its excellent specificity for single-base mismatched DNA.
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Técnicas Biossensoriais/métodos , Genes ras , Ouro/química , Peroxidase do Rábano Silvestre/metabolismo , Nanopartículas Metálicas/química , Sondas de DNA/química , Sondas de DNA/genética , Espectroscopia Dielétrica , Humanos , Estreptavidina/metabolismoRESUMO
A simple electrochemical sensor for sensitive and selective DNA detection was constructed based on gold nanorods (Au NRs) decorated graphene oxide (GO) sheets. The high-quality Au NRs-GO nanocomposite was synthesized via the electrostatic self-assembly technique, which is considered a potential sensing platform. Differential pulse voltammetry was used to monitor the DNA hybridization event using methylene blue as an electrochemical indicator. Under optimal conditions, the peak currents of methylene blue were linear with the logarithm of the concentrations of complementary DNA from 1.0 × 10(-9) to 1.0 × 10(-14)M with a detection limit of 3.5 × 10(-15)M (signal/noise=3). Moreover, the prepared electrochemical sensor can effectively distinguish complementary DNA sequences in the presence of a large amount of single-base mismatched DNA (1000:1), indicating that the biosensor has high selectivity.
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Técnicas Biossensoriais/instrumentação , DNA/análise , Técnicas Eletroquímicas/instrumentação , Ouro/química , Grafite/química , Nanotubos/química , Desenho de Equipamento , Limite de Detecção , Nanotubos/ultraestrutura , Hibridização de Ácido Nucleico , Óxidos/químicaRESUMO
Numerous articles have reported the involvement of linker in regulating bioactivity of tandem-repeat galectins. We hypothesize that linker interacts with N/C-CRDs to regulate the bioactivity of tandem-repeat galectins. To further investigate structural molecular mechanism of linker in regulating bioactivity of Gal-8, Gal-8LC was crystallized. Gal-8LC structure revealed formation of ß-strand S1 by Asn174 to Pro176 from linker. S1-strand interacts with C-terminal of C-CRD via hydrogen bond interactions, mutually influencing their spatial structures. Our Gal-8 NL structure have demonstrated that linker region from Ser154 to Gln158 interacts with the N-terminal of Gal-8. Ser154 to Gln158 and Asn174 to Pro176 are likely involved in regulation of Gal-8's biological activity. Our preliminary experiment results revealed different hemagglutination and pro-apoptotic activities between full-length and truncated forms of Gal-8, indicating involvement of linker in regulating these activities. We generated several mutant and truncated forms of Gal-8 (Gal-8 M3, Gal-8 M5, Gal-8TL1, Gal-8TL2, Gal-8LC-M3 and Gal-8_177-317). Ser154 to Gln158 and Asn174 to Pro176 were found to be involved in regulating hemagglutination and pro-apoptotic activities of Gal-8. Ser154 to Gln158 and Asn174 to Pro176 are critical functional regulatory regions within linker. Our study holds significant importance in providing a profound understanding of how linker regulates biological activity of Gal-8.
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Galectinas , Hemaglutinação , Humanos , Galectinas/químicaRESUMO
Purpose: Acupuncture has been recognized as an effective and safe alternative therapy for migraine, but its central mechanism has not yet been adequately explained. Meanwhile, research into the clinical efficacy and central mechanism of true acupuncture (TA) and sham acupuncture (SA) is lacking. It is necessary to investigate whether TA has better efficacy than SA, and how they achieve different effects. This study aims to evaluate the efficacy of TA and SA, observe the brain response caused by TA and SA, and further investigate the central nervous mechanism of TA and SA treatment for patients with migraine. Patients and Methods: This is a randomized controlled neuroimaging trial combining acupuncture treatment with functional magnetic resonance imaging, with patients and outcome assessors blinded. A total of 60 patients with migraine will be randomly allocated to receive 12 sessions of either TA or SA treatments (three sessions per week for 4 weeks), and 30 healthy participants will be recruited as the healthy control (HC) group. Outcome assessment and neuroimaging will be conducted before and after the entire intervention. A headache diary and questionnaires of life quality and psychological properties will be used to evaluate clinical efficacy. Multimodal magnetic resonance imagining data analysis will be used to investigate the central mechanism of TA or SA in treating migraine. Pearson's correlation analysis will be used to reveal the relationship between the brain response and clinical improvements. Conclusion: The results of this study will reveal the brain response to TA and SA in patients with migraine and contribute to further expanding the knowledge of their central mechanism. Study Registration: This trial has been approved by the ethics committee of Dongzhimen Hospital affiliated to Beijing University of Chinese Medicine (DZMEC-KY-2020-38) and registered in the Chinese Clinical Trial Registry (registration number ChiCTR2000033995).
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Photocatalytic overall water splitting is a promising approach to overcome the environmental and energy crisis. However, developing effective photocatalysts with well activity, light absorption, and photogenerated carrier lifetime is still a challenge. Herein, combining extensive first-principles and nonadiabatic molecular dynamics calculations, we find that microporous carbon-nitride nanosheets with a pyridinic nitrogen, such as C2N and C6N6, possess the pentacoordinated silicon intermediates' bonding environment. The pentacoordinated silicon as intermediates exhibits good photocatalytic performance for the difficult four-electronic oxygen evolution reaction. The overpotential is only 0.55 V for C2N, which is significantly lower than that of the tetracoordinated silicon intermediates (2.00 V). Simultaneously, the decoration of the silicon group not only widens the absorption range of visible light but also maintains the lifetime of photogenerated carriers on the nanosecond scale, which enhances the application efficiency of solar energy. Our work paves a new route for advancing photocatalytic overall water splitting.
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Compared with single-atom catalysts, clusters not only possess more metal-loadings and stability but also provide flexible active sites to break the linear scaling relationship of multistep reactions. However, exploring precise structure-activity relationships and the synergistic effect between clusters and nanosheets is still in its infancy. Here, based on first-principles and nonequilibrium Green's function simulation, the C2N-supported Fe and Co tetrahedral clusters exhibit remarkable bifunctional catalytic performance with a very low overpotential of hydrogen (0.12 and 0.07 V) /oxygen (0.20 and 0.55 V) evolution reactions (HER/OER), respectively. The C2N-regulated Fe and Co clusters have suitable d-band centers around the Fermi surface for HER. In turn, the Fe and Co clusters activate the subadjacent dual-carbon sites for OER. Simultaneously, the cluster enhances the electronic conductivity of C2N, and the initial current only needs ultralow bias voltage around 0.1-0.4 V. The desired metal cluster regulation strategy offers cost-effective potential for advancing clean energy technology.
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While the GII.4 norovirus was the predominant genotype, non-GII.4 genotype was increasingly focused since the non-GII.4 genotype caused regional epidemics. In this study, the detection rate was16.51% (183/1108) in Ningxia from January to December 2020. Among identified genotypes, GII.4[P31] and GII.4[P16] were the dominant genotypes (nâ¯=â¯20 and 18, respectively) while GII.6[P7] was the main type (nâ¯=â¯6) in non-GII.4 strains which was mainly detected in from May to July. The whole genome sequences of the norovirus diarrhea samples identified as GII.6 [P7] with Ctâ¯≤â¯30 collected in 2020 were determined. In this study, the complete genome sequences of norovirus strains PL20-044 and QTX20-071 were identified and analyzed phylogenetically. Phylogenetic analysis of the ORF1and ORF2 regions showed that these strains evolved from the GII·P7-GII.6 strains detected in recent years from different country. The results showed that PL20-044 had intra-type recombination with GII·P7-GII.6c and GII·P7-GII.6a, while QTX20-071 had intre-type recombination within GII·P7-GII.6a. The evolutionary rates of the RdRp gene region of the GII·P7 genotype and the VP1 gene region of the GII.6 genotype were 2.91â¯×â¯10-3 (95%HPDs2.32-3.51â¯×â¯10-3) and 2.61â¯×â¯10-3 (95%HPDs2.14-3.11â¯×â¯10-3) substitutions/site/year, respectively. Comparative analysis of the amino acid mutation sites in VP1 with the GII·P7-GII.6a strains before 1997, the later detected strains have changed in aa131 and aa354. Moreover, PL20-044 strains showed special mutations at aa316 and aa395. These results help to understand the norovirus genotype circulating in the human population in Ningxia, and discover the evolutionary characteristics of the GII·P7-GII.6 strain.
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Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Gastroenterite/epidemiologia , Filogenia , Norovirus/genética , Infecções por Caliciviridae/epidemiologia , Genótipo , China/epidemiologiaRESUMO
Photocatalytic overall water splitting is a potential strategy to address energy crisis and environmental issues. However, it remains a great challenge to design an efficient photocatalyst, which not only possesses large spatial separation of photogenerated electrons and holes (PEH) to suppress recombination, but also can preserve the redox capability to drive the reaction. Herein, we design a new type of sandwich-polarized heterojunction by inserting a polarized semiconductor into the interlayer of the conventional photocatalyst. The inserted sublayer with out-of-plane polarization can induce a large electrostatic potential difference between the top and bottom photocatalytic sublayers. Then, the band edges of the top and bottom sublayers can be shifted to form the type II band alignment. Also, the valence band maximum and conduction band minimum will be located on different photocatalytic sublayers to facilitate the spatial separation of PEH. Simultaneously, different from the conventional type II heterojunction that reduces the redox capability, the electrostatic potential difference also acts as an auxiliary booster to offset the reduced redox potential of PEH. Taking the C2N/In2Se3/C2N heterojunction as an example, the polarized In2Se3 effectively promotes the interface transfer of PEH in 1-5 ps and extends the lifetime of PEH to â¼186 ns, which is about six times that of bilayer C2N. Simultaneously, the redox power of C2N is well preserved. Our work offers a promising scheme to advance the photocatalytic overall water splitting.
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INTRODUCTION: Migraine is a common headache disorder. Many studies have used magnetic resonance imaging (MRI) to explore the possible pathogenesis of migraine, but they have not reached consistent conclusions and lack rigorous multiple comparison correction. Thus, this study investigates the mechanisms of migraine development from the perspective of altered functional connectivity (FC) in brain regions by using data-driven and regions of interest (ROI)-based approaches. METHODS: Resting-state functional MRI data were collected from 30 patients with migraine and 40 healthy controls (HCs) matched for age, gender, and years of education. For the data-driven method, we used a voxel-mirrored homotopic connectivity (VMHC) approach to compare the FC between the patients and HCs. For the ROI-based method, significant differences in VMHC maps between the patients and HCs were defined as ROI. The seed-based approach further revealed significant differences in FC between the seeds and the other brain regions. Furthermore, the correlations between abnormal FC and clinical characteristics of patients were investigated. A rigorous multiple comparison correction was used with false discovery rate and permutation test (5000 times). RESULTS: In comparison with the controls group, patients showed enhanced VMHC in the bilateral thalamus. We also observed enhanced FC between the left thalamus and the left superior frontal gyrus, and increased FC between the right thalamus and the left middle frontal gyrus (Brodmann area 45 and Brodmann area 8) in patients. Further analysis showed that the FC values in the left superior frontal gyrus and left middle frontal gyrus were negatively corrected with visual analogue scale scores or attack times for headaches. CONCLUSIONS: Patients with migraine showed altered VMHC in the bilateral thalamus, and abnormal FC of bilateral thalamus and other brain regions. The abnormalities in thalamic FC are a likely mechanism for the development of migraine. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000033995. Registered on 20 June 2020.
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In order to prepare a titanium with a low elastic modulus and good antibacterial property to meet the requirements as a biomedical material, Ti-13Nb-13Zr-5Cu (TNZ-5Cu) alloy was prepared by high vacuum consume electric arc melting furnace and then subjected to a solution treatment at 950 °C followed by a short-term aging treatment at 600 °C, for 15 min, 30 min, 1 h and 2 h, respectively. The microstructure, mechanical property, antibacterial property and biocompatibility of TNZ-5Cu were investigated in detail. The research results have shown that the solid solution treated alloy was mainly composed of ß-phase and αâ³-phase, while the aged alloys of ß-phase, αâ³-phase, α-phase and Ti2Cu. Compared with Ti-13Nb-13Zr alloy (65 GPa) and Ti-6Al-4 V alloy (111 GPa), the elastic modulus of TNZ-5Cu alloy after solution treatment was about 72 GPa and increased with the aging treatment up to 85 GPa, and the hardness was maintained at a higher level than that of Ti-13Nb-13Zr alloys (288 HV). The bacteria plate count results showed that the antibacterial ability of TNZ-5Cu alloy increased with the extension of the aging duration from <60% at 15-30 min to >90% at 1-2 h. Cell experiments showed that all TNZ-5Cu alloy had good cell compatibility. The low modulus and the antibacterial property could provide potential to avoid stress shield and device-related inflection in the clinical application.
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Ligas , Titânio , Ligas/farmacologia , Antibacterianos/farmacologia , Materiais Biocompatíveis , Módulo de Elasticidade , Teste de Materiais , Titânio/farmacologiaRESUMO
Background: Long non-coding RNAs (lncRNAs) can remarkably regulate human malignancies in terms of the development and the progression. Previously, lncRNA LINC00847 (LINC00847) has been reported to present dysregulation in several tumors. However, the expression and function of LINC00847 in non-small cell lung cancer (NSCLC) have not been investigated. Methods: RT-qPCR was performed to determine the expressions of LINC00847 in collected tissue samples and cell lines. The clinical significance of LINC00847 was statistically analyzed. CCK-8 test, cell scratch test and trans-well test were used to evaluate the proliferation, invasion and migration abilities of NSCLC cells, respectively. The xenograft tumor model was constructed to confirm the effects of LINC00847 knockdown on NSCLC in vivo. Further, luciferase reporter assays and Western blot were performed to explore molecular mechanisms underlying the functions of LINC00847. Results: Increased expressions of LINC00847 were observed in NSCLC samples as well as cell lines. Additionally, E2F1 could be capable of directly binding to the LINC00847 promoter region, followed by promoting its expression. Clinically, LINC00847 high-expression could lead to poor prognosis of NSCLC patients. Functionally, LINC00847 knockdown noticeably repressed NSCLC cell growth and metastasis. Mechanically, miR-147a/IFITM1 axis was a downstream target of LINC00847, and silencing of miR-147a could rescue the anti-cancer effects of LINC00847 knockdown on NSCLC cell behaviors. Conclusion: Overall, up regulation of LINC00847 induced by E2F1 promoted the progression of NSCLC by modulating miR-147a/IFITM1 axis, representing a novel regulatory mechanism for NSCLC progression.
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OBJECTIVE: To investigate the effect of acupuncture on default mode network (DMN) in migraine patients without aura based on functional Magnetic Resonance Imaging (fMRI). METHODS: Fifteen patients with migraine were included and treated with acupuncture based on "root-knot" theory (Zuqiaoyin [GB 44] for shaoyang headache, Lidui [ST 45] for yangming headache, Zhiyin [BL 67] for taiyang headache, and ashi point), once every other day, three times a week for 4 weeks. The patients received fMRI scanning before and after acupuncture treatment, the effect of acupuncture on DMN in patients with migraine was observed; the frequency of migraine attack, visual analogue scale (VAS) score and the using of analgesic medication before and after treatment were recorded to evaluate the curative effect of acupuncture; the migraine-specific quality of life questionnaire (MSQ), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to evaluate the improvements of quality of life and emotional state. RESULTS: Compared before acupuncture, the functional connections of left parahippocampal cortex (PHC) and anterior medial prefrontal cortex (aMPFC), dorsal medial prefrontal cortex (dMPFC) and lateral temporal cortex (LTC) in DMN after acupuncture were weakened (P<0.05), and the functional connections of bilateral posterior cingulate cortex (PCC) and dMPFC were weakened (P<0.05). Compared before treatment, the frequency of migraine attack, VAS, SAS and SDS scores after treatment were decreased (P<0.05), and MSQ score was increased (P<0.05). CONCLUSION: Acupuncture shows good clinical efficacy for migraine without aura, and could adjust the functional connection of DMN.
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Terapia por Acupuntura , Transtornos de Enxaqueca , Mapeamento Encefálico , Rede de Modo Padrão , Humanos , Espectroscopia de Ressonância Magnética , Transtornos de Enxaqueca/diagnóstico por imagem , Transtornos de Enxaqueca/terapia , Qualidade de VidaRESUMO
In atomically thin two-dimensional van der Waals (2D vdW) heterostructures, spatially separated interlayer excitons play an important role in the optoelectronic performance and show great potential for the exploration of many-body quantum phenomena. A commonly accepted formation mode for interlayer excitons is via a two-step intralayer exciton transfer mechanism, namely, photo-excited intralayer excitons are initially generated in individual sublayers, and photogenerated electrons and holes are then separated into opposite sublayers based on the type-II band alignment. Herein, we expand the concept of interlayer exciton formation and reveal that bright interlayer excitons can be generated in one step by direct interlayer photoexcitation in 2D vdW heterostructures that have strong interlayer coupling and a short photoexcitation channel. First-principles and many-body perturbation theory calculations demonstrate that indium selenide/antimonene and indium selenide/black phosphorus heterostructures are two promising systems that show an exceptionally large interlayer transition probability (>500 Debye2). This study enriches the understanding of interlayer exciton formation and provides a new avenue to acquiring strong interlayer excitons in artificial 2D vdW heterostructures.