Search

Superior catalytic activity toward As(iii) for P FeCo2O4−x/GCE with increasing reductive Fe(ii)/Co(ii) sites.

Overgeneralization of fear to harmless situations is a core feature of anxiety disorders resulting from acute stress, yet the mechanisms by which fear becomes generalized are poorly understood. Here we show that generalized fear in mice in response to footshock results from a transmitter switch from glutamate to GABA in serotonergic neurons of the lateral wings of the dorsal raphe. We observe a similar change in transmitter identity in the postmortem brains of PTSD patients. Overriding the transmitter switch in mice using viral tools prevents the acquisition of generalized fear. Corticosterone release and activation of glucocorticoid receptors trigger the switch, and prompt antidepressant treatment blocks the co-transmitter switch and generalized fear. Our results provide new understanding of the plasticity involved in fear generalization.One sentence summaryAcute stress produces generalized fear by causing serotonergic neurons to switch their co-transmitter from glutamate to GABA

Stable matching of neurotransmitters with their receptors is fundamental to synapse function, to achieve reliable and robust communication in neural circuits. Presynaptic neurotransmitters regulate selection of postsynaptic transmitter receptors. However, whether postsynaptic receptors regulate selection of presynaptic transmitters is unknown. Here we show that blockade of postsynaptic acetylcholine receptors at the neuromuscular junction leads to loss of the cholinergic phenotype in motor neurons and stabilization of an earlier, developmentally transient glutamatergic phenotype. Exogenous postsynaptic expression of GABAAreceptors leads to the stabilization of an earlier, developmentally transient GABAergic motor neuron phenotype. Both acetylcholine receptors and GABA receptors are linked to presynaptic neurons through trans-synaptic bridges. Knock-down of different components of these trans-synaptic bridges prevents stabilization of the cholinergic and GABAergic phenotypes. We conclude that this bidirectional communication enforces a match between transmitter and receptor and ensures the fidelity of synaptic transmission. Our findings suggest a role of dysfunctional transmitter receptors in neurological disorders that involve the loss of the presynaptic transmitter.

Neurotransmitter switching is a form of brain plasticity in which an environmental stimulus causes neurons to replace one neurotransmitter with another, often resulting in changes in behavior. This raises the possibility of applying a specific environmental stimulus to induce a switch that can enhance a desirable behavior or ameliorate symptoms of a specific pathology. For example, a stimulus inducing an increase in the number of neurons expressing dopamine could treat Parkinson's disease, or one affecting the number expressing serotonin could alleviate depression. This may already be producing successful treatment outcomes without our knowing that transmitter switching is involved, with improvement of motor function through physical activity and cure of seasonal depression with phototherapy. This review presents prospects for future investigation of neurotransmitter switching, considering opportunities and challenges for future research and describing how the investigation of transmitter switching is likely to evolve with new tools, thus reshaping our understanding of both normal brain function and mental illness.

Decreased cognitive ability is a major consequence of exposure to drugs of abuse, but the underlying neuroplastic changes have been elusive. We show that both phencyclidine and methamphetamine cause a population of prelimbic pyramidal neurons to switch from a glutamatergic to a GABAergic phenotype. Overriding the gain of GABA with RNA-interference prevents drug-induced cognitive deficits and locomotor sensitization, connecting the change in neurotransmitter identity with altered behavior. Chemogenetic suppression of drug-induced hyperactivity also prevents the change in transmitter phenotype or reverses it after it has occurred, preventing or rescuing the associated behavioral changes. These findings may provide therapeutic opportunities to mitigate drug-induced cognitive deficits by manipulating electrical activity in the prelimbic cortex.

A method to measure the detailed performance of polycapillary x-ray optics by a pinhole and charge coupled device (CCD) detector was proposed in this study. The pinhole was located between the x-ray source and the polycapillary x-ray optics to determine the illuminating region of the incident x-ray beam on the input side of the optics. The CCD detector placed downstream of the polycapillary x-ray optics ensured that the incident x-ray beam controlled by the pinhole irradiated a specific region of the input surface of the optics. The intensity of the output beam of the polycapillary x-ray optics was obtained from the far-field image of the output beam of the optics captured by CCD detector. As an application example, the focal spot size, gain in power density, transmission efficiency, and beam divergence of different parts of a polycapillary focusing x-ray lenses (PFXRL) were measured by a pinhole and CCD detector. Three pinholes with diameters of 500, 1000, and 2000 μm were used to adjust the diameter of the incident x-ray beam illuminating the PFXRL from 500 μm to the entire surface of the input side of the PFXRL. The focal spot size of the PFXRL, gain in power density, transmission efficiency, and beam divergence ranged from 27.1 μm to 34.6 μm, 400 to 3460, 26.70% to 5.38%, and 16.8 mrad to 84.86 mrad, respectively.

BackgroundA recent genome-wide copy number variations (CNVs) scan identified a 16q12.2 deletion that included the carboxylesterase 1 (CES1) gene, which is important in the metabolism of fatty acids and cholesterol. We aimed to investigate whether CES1 CNVs was associated with susceptibility to non-alcoholic fatty liver disease (NAFLD) in a Chinese Han population.MethodsA case-control study was conducted among 303 patients diagnosed with NAFLD and 303 age (± 5) and sex-matched controls from the Affiliated Nanping First Hospital of Fujian Medical University in China. The copy numbers of CES1 were measured using TaqMan quantitative real-time polymerase chain reaction (qPCR) and serum CES1 was measured using enzyme-linked immunosorbent assays. The Chi-squared test and a logistic regression model were used to evaluate the association between CES1 CNVs and NAFLD susceptibility.ResultsThe distribution of CES1 CNVs showed a higher frequency of CNVs loss (< 2) among patients; however, the difference was not significant (P = 0.05). After controlling for other known or suspected risk factors for NAFLD, CES1 CNVs loss was significantly associated with greater risk of NAFLD (adjusted OR = 2.75, 95% CI: 1.30–5.85, P = 0.01); while CES1 CNVs gain (>2) was not. There was a suggestion of an association between increased CES1 serum protein levels and CNVs losses among cases, although this was not statistically significant (P=0.07).ConclusionsCopy number losses (< 2) of CES1 contribute to susceptibility to NAFLD in the Chinese Han population.

Background The prevalence of Non-alcoholic fatty liver disease (NAFLD) is increasing and emerging as a global health burden. In addition to environmental factors, numerous studies have shown that genetic factors play an important role in the development of NAFLD. Copy number variation (CNV) as a genetic variation plays an important role in the evaluation of disease susceptibility and genetic differences. The aim of the present study was to assess the contribution of CNV to the evaluation of NAFLD in a Chinese population. Methods Genome-wide analysis of CNV was performed using high-density comparative genomic hybridisation microarrays (ACGH). To validate the CNV regions, TaqMan real-time quantitative PCR (qPCR) was utilized. Results A total of 441 CNVs were identified, including 381 autosomal CNVs and 60 sex chromosome CNVs. By merging overlapping CNVs, a genomic CNV map of NAFLD patients was constructed. A total of 338 autosomal CNVRs were identified, including 275 CNVRs with consistent trends (197 losses and 78 gains) and 63 CNVRs with inconsistent trends. The length of the 338 CNVRs ranged from 5.7 kb to 2.23 Mb, with an average size of 117.44 kb. These CNVRs spanned 39.70 Mb of the genome and accounted for ~ 1.32% of the genome sequence. Through Gene Ontology and genetic pathway analysis, we found evidence that CNVs involving nine genes may be associated with the pathogenesis of NAFLD progression. One of the genes (NLRP4 gene) was selected and verified by quantitative PCR (qPCR) method with large sample size. We found the copy number deletion of NLRP4 was related to the risk of NAFLD. Conclusions This study indicate the copy number variation is associated with NAFLD. The copy number deletion of NLRP4 was related to the risk of NAFLD. These results could prove valuable for predicting patients at risk of developing NAFLD.

Significance The discovery that neurotransmitter identity is regulated by activity in the adult mammalian brain during a stress response raises questions about the extent and function of this plasticity. Specific synapses are associated with the release of a particular neurotransmitter or transmitters on the basis of evidence obtained under a single set of conditions. Transmitter switching endows the connectome with greater plasticity: Activity-dependent revision of signaling provides another dimension of flexibility to regulate normal behavior. Changes in transmitter identity are also positioned to contribute to diseases of the nervous system. Neurotransmitter imbalance has long been implicated in common neurological and psychiatric disorders, provoking interest in transmitter switching as a therapeutic tool for patients., Neurotransmitter switching in the adult mammalian brain occurs following photoperiod-induced stress, but the mechanism of regulation is unknown. Here, we demonstrate that elevated activity of dopaminergic neurons in the paraventricular nucleus of the hypothalamus (PaVN) in the adult rat is required for the loss of dopamine expression after long-day photoperiod exposure. The transmitter switch occurs exclusively in PaVN dopaminergic neurons that coexpress vesicular glutamate transporter 2 (VGLUT2), is accompanied by a loss of dopamine type 2 receptors (D2Rs) on corticotrophin-releasing factor (CRF) neurons, and can lead to increased release of CRF. Suppressing activity of all PaVN glutamatergic neurons decreases the number of inhibitory PaVN dopaminergic neurons, indicating homeostatic regulation of transmitter expression in the PaVN.

The electrochemical method for highly sensitive determination of arsenic(III) in real water samples with noble-metal-free nanomaterials is still a difficult but significant task. Here, an electrochemical sensor driven by noble-metal-free layered porous Fe3O4/Co3S4 nanosheets was successfully employed for As(III) analysis, which was prepared via a facile two-step method involves a hydrothermal treatment and a subsequent sulfurization process. As expected, the electrochemical detection of As(III) in 0.1 M HAc-NaAc (pH 6.0) by square wave anodic stripping voltammetry (SWASV) with a considerable sensitivity of 4.359 μA/μg·L−1 was obtained, which is better than the commonly used noble metals modified electrodes. Experimental and characterization results elucidate the enhancement of As(III) electrochemical performance could be attributed to its nano-porous structure, the presence of oxygen vacancies and strong synergetic coupling effects between Fe3O4 and Co3S4 species. Besides, the Fe3O4/Co3S4 modified screen printed carbon electrode (Fe3O4/Co3S4-SPCE) shows remarkable stability and repeatability, valuable anti-interference ability and could be used for detection in real water samples. Consequently, the results confirm that as-prepared porous Fe3O4/Co3S4 nanosheets is identified as a promising modifier to detect As(III) in real sample analysis.

Background: Non-alcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease. Diet and lifestyle changes have dramatically increased its prevalence worldwide. This meta-analysis was performed to investigate the efficacy of physical activity intervention on liver-specific endpoints in the NAFLD population, namely hepatic enzyme levels, serum lipid levels, and glucose metabolism. Methods: PubMed and China National Knowledge Infrastructure (CNKI) databases were searched for randomized clinical trials of physical activity intervention on patients with NAFLD through to April 20, 2019. Effect sizes were reported as the standardized mean differences (SMD) and 95% confidence intervals (CI). The quality of the included studies was assessed using the Cochrane risk of bias tool. Meta-analyses were conducted using random-effect or fixed-effect models depending on the significance of heterogeneity. Clinical variability was investigated using subgroup analyses according to physical activity type and duration. Results: Eleven studies with a cumulative total of 1000 participants met the selection criteria. Physical activity was associated with small reductions in three hepatic enzyme parameters: alanine aminotransferase, (SMD: -0.17, 95% CI: -0.29 to -0.05), aspartate aminotransferase, (SMD: -0.25, 95% CI: -0.37, -0.13), and γ-glutamyl transferase (SMD: -0.21, 95% CI: -0.35, -0.08). Significant small improvements were also found for total cholesterol (SMD: -0.22, 95% CI: -0.34, -0.09), triglycerides (SMD: -0.20, 95% CI: -0.32 to -0.07), and low-density lipoprotein cholesterol (SMD: -0.26, 95% CI: -0.39 to -0.13). Physical activity also slightly improved two glucose metabolism parameters: fasting glucose (SMD: -0.25, 95% CI: -0.37 to -0.12) and homeostasis model assessment of insulin resistance (SMD: -0.38, 95% CI: -0.52, -0.24). High-density lipoprotein cholesterol and fasting insulin between the physical intervention group and control group were not significantly different. Subgroup analysis suggested that both aerobic exercise alone and resistance exercise alone could improve most liver function and glucose metabolism outcomes and that longer exercise duration generally had better improvement effects. The difference between all subgroups was not significant, except for the TG subgroups categorized by physical activity type. Conclusions: Our findings suggest that physical activity alone can only slightly improve hepatic enzyme levels, serum lipid levels, and glucose metabolism in patients with NAFLD.

Background Non-alcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease nowadays. Changes in diet and lifestyle have led to a dramatic increase in the prevalence of NAFLD around the world. This meta-analysis is to investigate the efficacy of physical activity intervention on liver-specific endpoints in the population with NAFLD, including hepatic enzyme, serum lipid, glucose metabolism and intra-hepatic lipid. Methods PubMed and China National Knowledge Infrastructure (CNKI) databases were searched for randomized clinical trials of physical activity intervention on NAFLD patients through April 20th, 2019. Effect sizes were reported as standardized mean difference (SMD) and 95% confidence intervals (CI). Quality of included studies was assessed according to the Cochrane risk of bias tool. Meta-analyses were conducted using random-effect or fixed-effect models depending on the significance of heterogeneity. Subgroup analyses according to types and duration of physical activity were conducted to investigate clinical variability. Results Nine studies with a cumulative total of 951 participants met selection criteria. Physical activity was found associated with small reductions in hepatic enzyme parameters: ALT (SMD -0.17, 95% CI:-0.30 to − 0.05), AST (SMD -0.25, 95% CI: − 0.38, − 0.13) and GGT (SMD -0.22, 95% CI: − 0.36, − 0.08). Significant small improvements were also found in serum lipid parameters including TC (SMD = − 0.22, 95% CI: − 0.34, − 0.09), TG (SMD = − 0.18, 95% CI: − 0.31 to − 0.06) and LDL-C (SMD = − 0.26, 95% CI: − 0.39 to − 0.13). Significant improvement was also found in intra-hepatic lipid content (SMD = − 0.21, 95% CI: − 0.36 to − 0.06) There was no difference between physical intervention group and control group in HDL and three glucose metabolism parameters. Subgroup analysis suggested both aerobic exercise alone and resistance exercise alone can improve most liver function and longer period of exercise generally had better improvement effect. Conclusions Our findings suggest that physical activity alone can only slightly improve hepatic enzyme levels, most serum lipid levels and intra-hepatic lipid content in non-diabetic patients with NAFLD.

Physical exercise promotes motor skill learning in normal individuals and those with neurological disorders but its mechanism of action is unclear. We find that one week of voluntary wheel running enhances the acquisition of motor skills in normal adult mice. One week of running also induces switching from ACh to GABA expression in neurons in the caudal pedunculopontine nucleus (cPPN). Consistent with regulation of motor skills, we show that the switching neurons make projections to the substantia nigra (SN), ventral tegmental area (VTA) and ventrolateral-ventromedial nuclei of the thalamus (VL-VM). Use of viral vectors to override transmitter switching blocks the beneficial effect of running on motor skill learning. We suggest that neurotransmitter switching provides the basis by which sustained running benefits motor skill learning, presenting a target for clinical treatment of movement disorders., Exercise promotes motor skill learning via unclear mechanisms. Here, the authors show that running wheel training results in neurotransmitter switching in caudal pedunculopontine nucleus neurons of mice. These neurons project to several brain regions, regulating the acquisition of motor skills.

The heterojunction was formed between two kinds of coupling semiconductors , which improved the charge separation efficiency of system, widened the spectral response range of catalysts and improved photocatalytic propertirs of catalysts. The process of preparation of semiconductors coupling was easily affected by preparation methods and reaction temperature and so on, which would cause the changes in crystal structure and surface properties of coupling semiconductors, thus photocatalytic quantum efficiency of coupling semiconductors was increased. In this article, the following three aspects were mainly discussed. (1) About the coupled system of halogen bismuth oxide and oxide, because generaling BiOX with the semiconductor material compound, the efficient heterojunction structure could be formed, photocatalytic performances of the photocatalytic degradation of pollutants were improved. (2) About the coupled system of AgX and BiOX, compared with the pure AgI or BiOI, composite photocatalytic materials of AgI/BiOI had higher photocatalytic reactivity in visible light. (3) About the coupled system of halogen bismuth oxide and other compounds, after Bi2S3 coupled with BiOX, photoproduction electronic migrated in the two kinds of catalysts, the separation efficiency of electrons and holes was improved, and photocatalytic performances of coupling compound were improved. In addition, in recent years, the latest research progress of the preparation method, the influencing factors of the photocatalytic performance and improving the utilization efficiency of visible light of semiconductors coupling at home and abroad was reviewed in this paper. Finally, the main problems and the future striving direction in semiconductors coupling were presented.

Two ligand substitution reactions on aqueous complexes of Al, Ga and In, water-exchange and aqua/fluoride substitution reactions, were investigated using density functional theory (DFT), and the preferred substituted mechanisms were estimated based on the activated energy barriers. A series of mechanistic changeovers were found and interpreted at the molecular level. Four factors influencing substitution mechanisms were summarized, i.e. the size of central metal ions, the volume of entering ligands, the charge of clusters, and structural rigidity. The present study provides an approach to probe the ligand substitution mechanism of some reactions inaccessible experimentally.

Microglia are the resident immune cells in the CNS and play diverse roles in the maintenance of CNS homeostasis. Recent studies have shown that microglia continually survey the CNS microenvironment and scavenge cell debris and aberrant proteins by phagocytosis and pinocytosis, and that reactive microglia are capable to present antigens to T cells and initiate immune responses. However, how microglia process the endocytosed contents and evoke an immune response remain unclear. Here we report that a size-dependent selective transport of small soluble contents from the pinosomal lumen into lysosomes is critical for the antigen processing in microglia. Using fluorescent probes and water-soluble magnetic nanobeads of defined sizes, we showed in cultured rodent microglia, and in a cell-free reconstructed system that pinocytosed proteins become degraded immediately following pinocytosis and the resulting peptides are selectively delivered to major histocompatibility complex class II (MHC-II) containing lysosomes, whereas undegraded proteins are retained in the pinosomal lumen. This early size-based sorting of pinosomal contents relied on the formation of transient tunnel between pinosomes and lysosomes in a Rab7- and dynamin II-dependent manner, which allowed the small contents to pass through but restricted large ones. Inhibition of the size-based sorting markedly reduced proliferation and cytokine release of cocultured CD4+T cells, indicating that the size-based sorting is required for efficient antigen presentation by microglial cells. Together, these findings reveal a novel early sorting mechanism for pinosomal luminal contents in microglial cells, which may explain how microglia efficiently process protein antigens and evoke an immune response.

Quantum electrodynamics (QED) effects may be included in physical processes of magnetar and pulsar magnetospheres with strong magnetic fields. Involving the quantum corrections, the Maxwell electrodynamics is modified to non-linear electrodynamics. In this work, we study the force-free magnetosphere in non-linear electrodynamics in a general framework. The pulsar equation describing a steady and axisymmetric magnetosphere is derived, which now admits solutions with corrections. We derive the first-order non-linear corrections to the near-zone dipole magnetosphere in some popular non-linear effective theories. The field lines of the corrected dipole tend to converge on the rotational axis so that the fields in the polar region are stronger compared to the pure dipole case., Comment: 12 pages, 1 figure

The mixed-phase TiO 2 photocatalysts with different anatase/rutile/brookite ratios and high specific surface area (157–218 m 2 /g) were prepared by hydrothermal method at 100 °C and the effect of rutile content in TiO 2 on the BET surface area, light absorption and separation efficiency of photogenerated charge carriers was studied and correlated to the photocatalytic activity of TiO 2 . Rutile content increased from 0% to 100% by increasing the amount of TiCl 4 in aqueous phase and the initial pH value of reaction solution played an important role in the phase composition of TiO 2 . The photocatalytic mechanism of mixed-phase TiO 2 was discussed.

With the development of electric vehicle industry, it is necessary to construct more electric vehicle charging stations to promote the popularization of electric vehicles. As photovoltaic generation owns flexible installing, convenient power supplying, and environmental protecting characteristics, it is suitable for providing power for electric vehicle charging stations and reducing a network loads. After analyzed electric vehicle charging demand, this paper proposed the designing concept of the electric system for the photovoltaic generation mix charging station, which was based on the battery charging and discharging characteristics as well as its usage. Then, the paper provided a selection of electric equipments for the charging station and an electric wiring diagram after designing the electric system. This study and design may help for promoting construction of electric vehicle charging stations, and development and popularization of electric vehicles.

Thermal distribution in catalyst bed was investigated for the fixed-bed tri-reforming of methane over Pt modified Ni/MgO catalysts under atmospheric pressure, 850 °C, and space velocity of 2000−20000 h−1. The effects of the W/F on the thermal distribution of different catalysts were examined. The results indicated that for Pt modified Ni/MgO catalysts, the temperature profile depended on catalysts preparation method. According to the thermal distribution, for Pt modified Ni/MgO catalysts prepared by sequence method, the catalyst bed can be divided into tow zones: auto-thermo reforming zone and oxygen absent zone. Methane reforming proceeds in both zones together.

Eu2O3nanoparticles were fabricated by thermal decomposition of europium propionate crystals, which can be facilely obtained via crystallization. The decomposition and morphlogy of the crystallized product were characterized by X-ray diffractionmetry (XRD), simultaneous differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) as well as scanning electron microscopy (SEM). The effects of the calcination temperature on the resultant microstructures such as crystallinity, particle size and particle dispersibility were investigated by XRD and transmission electron microscopy (TEM). The results indicated the morphology of the as-calcined products shows transmissibility compared with the precursor and that the calcination temperature of europium propionate is crucial to evolution of the resultant morphology from three-dimensional network of agglomerated nanoparticles to dispersed nanoparticles.

Using Bi2O3 and MnC2 x 4H2O as raw materials, with HCl as solvent, photocatalysts of Mn-BiOCl with different molar ratio of Mn and Bi were prepared by a hydrolysis method. The obtained samples were characterized by XRD, HRTEM, TEM, UV-Vis DRS and SPS. The UV light photocatalytic activity of Mn-BiOCl was evaluated by using methyl orange as model compounds of photocatalytic reaction. The active species in the degradation process of methyl orange were studied. The results show that the Mn content of Mn-BiOCl photocatalysts has an important effect on the catalytic activity. When the molar ratio of Mn and Bi is 0.25%, the as-prepared Mn-BiOCl photocatalyst has the highest catalytic activity toward the degradation of methyl orange. Photocatalytic degradation rate of methyl orange can reach 95.1%.

Thermal distribution in catalyst bed was investigated for the fixed-bed tri-reforming of methane over Ni/Al 2 O 3 under atmospheric pressure, 750 – 950°C, and space velocity ( S V ) of 2000 – 20000 h −1 . The effects of the furnace temperature ( t f ), the space velocity, and the feed stock composition on the thermal distribution were examined. The results indicated that the temperature gradient of the catalyst bed in methane tri-reforming is smaller than that in methane partial oxidation. The temperature near the inlet of the catalyst bed ( t max ) is 80°C higher than t f when the feed composition n(CH 4 )/n(CO 2 )/n(H 2 O)/n(O 2 ) = 50/12.5/12.5/25 (by mol) and the space velocity S V = 20000 h −1 , whereas the temperature near the outlet of the catalyst bed is close to t f . The temperature difference between the inlet and the furnace Δ t max = t max – t f ) increases with the space velocity Δ t max = 30°C at 2000 h −1 , Δ t max = 80°C at 20000 h −1 ). No distinct hot spot is observed near the catalyst bed inlet when there is no oxygen in feed. Under specific condition, the lowest temperature in the catalyst bed ( t min ) is about 30 – 40°C lower than t f . According to the thermal distribution, the catalyst bed can then be divided into three zones: oxygen adequate zone, oxygen inadequate zone, and oxygen absent zone. Methane reforming proceeds in the first and second zones, while methane combustion proceeds only in the first zone and partial oxidation of methane proceeds only in the second zone.

Phosphogypsum, which contains more than 90% of the calcium sulfate dehydrate (CaSO4 · 2H2O), is a kind of important renewable gypsum resources. Unlike the natural gypsum, however, phosphorus, fluorine, organic matter and other harmful impurities in phosphogypsum limit its practical use. To ascertain the existence form, content and phase distribution of trace fluoride in phosphogypsum has important theoretical values in removing trace fluoride effectively. In this present paper, the main existence form and phase distribution of trace fluoride in phosphogypsum was investigated by the combination of X-ray photoelectron spectroscopy (XPS) and Electron microprobe analysis (EMPA). The results show that trace fluoride phase mainly includes NaF, KF, CaF2, K2SiF6, Na2SiF6, Na3AlF6, K3AlF6, AlF3 · 3H2O, AlF2.3(OH)0.7 · H2O, Ca5(PO4)3F, Ca10(PO4)6F2. Among them, 4.83% of fluorine exists in the form of fluoride (NaF, KF, CaF2); Accordingly, 8.43% in the form of fluoride phosphate (Ca5(PO4)3F, Ca10(PO4)6F2); 12.21% in the form of fluorine aluminate (Na3AlF6, K3AlF6); 41.52% in the form of fluorosilicate (K2SiF6, Na2SiF6); 33.02% in the form of aluminum fluoride with crystal water (AlF3 · 3H2O, AlF2.3(OH)0.7 · H2O). In the analysis of phase constitution for trace elements in solid samples, the method of combining XPS and EMPA has more advantages. This study also provides theoretical basis for the removal of trace fluorine impurity and the effective recovery of fluorine resources.

UV-Vis absorption spectra and electrochemical properties of 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-phenyl)porphyrin (TPPOH) and 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-methoxyphenyl) porphyrin [(p-OCH3)TPPOH] with different electron groups were investigated by experiments and density functional theory (DFT). Due to the introduction of para-methoxyl group (-OCH3), obvious red shift of 3 nm in the maximum absorbance of the UV-Vis spectra, negative shift in redox potential of (p-OCH3)TPPOH, and the decrease (0.06 eV) in the energy gap (DE) of the frontier highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) (of (p-OCH3)TPPOH occurred as compared to those of TPPOH. The results are due to that electron donating groups of -OCH3 increase the electron density of porphyrin ring in (p-OCH3)TPPOH. Electron distributions of the frontier orbital calculated by DFT showed that the increase in the energy levels of HOMO and LUMO, while the decrease of 0.05 eV in the energy gap. The agreement between experimental result and theoretical value and the further illustration of the mechanism for the spectral change and electrochemical properties provide important bases for the design and application of the porphyrin derivatives with different electron groups.

Microglial cells have important roles in maintaining brain homeostasis, and they are implicated in multiple brain diseases. There is currently interest in investigating microglial migration that results in cell accumulation at focal sites of injury. Here we describe a protocol for rapidly triggering and monitoring microglial migration by using a micropipette assay. This protocol is an adaptation of the axon turning assay using microglial cells. Chemoattractants released from the micropipette tip produce a chemotactic gradient that induces robust microglial migration. In combination with microscopic imaging, this assay allows simultaneous recording of cell movement and subcellular compartment trafficking, along with quantitative analysis. The actual handling time for the assay takes ∼2-3 h in total. The protocol is simple, inexpensive and convenient to set up, and it can be adopted to examine cell migration in multiple cell types, including cancer cells with a wide range of chemical signals.

Brain disturbances, like injuries or aberrant protein deposits, evoke nucleotide release or leakage from cells, leading to microglial chemotaxis and ingestion. Recent studies have identified P2Y12 purinergic receptors as triggers for microglial chemotaxis and P2Y6 receptors as mediators for phagocytosis. However, pinocytosis, known as the internalization of fluid-phase materials, has received much less attention. We found that ATP efficiently triggered pinocytosis in microglia. Pharmacological analysis and knockdown experiments demonstrated the involvement of P2Y4 receptors and the phosphatidylinositol 3-kinase/Akt cascade in the nucleotide-induced pinocytosis. Further evidence indicated that soluble amyloid beta peptide 1-42 induced self-uptake in microglia through pinocytosis, a process involving activation of P2Y4 receptors by autocrine ATP signaling. Our results demonstrate a previously unknown function of ATP as a "drink me" signal for microglia and P2Y4 receptors as a potential therapeutic target for the treatment of Alzheimer's disease.

Nano-rutile TiO2 photocatalysts with bigger specific surface area were prepared by a hydrolysis method at 323 K, and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), ultraviolet-visible diffuse reflection spectroscopy (UV-Vis DRS), infrared spectroscopy (IR) and photoelectrochemical (PEC). The ultraviolet (UV) and visible light photocatalytic activities of as-prepared rutile and anatase TiO2 nano-photocatalysts with almost same specific surface areas were evaluated by methyl orange (MO) as mode compound to photocatalytic reaction. The results of the photocatalytic experiment shows that when rutile and anatase have the similar specific surface area of approximately 95 m2.g-1, the UV light photocatalytic activity of rutile is comparable to that of anatase, while rutile shows significantly higher visible light photocatalytic activities than anatase. The photoelectrochemical experiment shows that the order of photocurrent densities of the catalysts from weak to strong is in accordance with the order of UV light photocatalytic activities of the catalysts from low to high under UV light irradiation.

Microglia are highly motile cells that act as the main form of active immune defense in the central nervous system. Attracted by factors released from damaged cells, microglia are recruited towards the damaged or infected site, where they are involved in degenerative and regenerative responses and phagocytotic clearance of cell debris. ATP release from damaged neural tissues has been suggested to mediate the rapid extension of microglial process towards the site of injury. However, the mechanisms of the long-range migration of microglia remain to be clarified. Here, we found that lysosomes in microglia contain abundant ATP and exhibit Ca(2+)-dependent exocytosis in response to various stimuli. By establishing an efficient in vitro chemotaxis assay, we demonstrated that endogenously-released ATP from microglia triggered by local microinjection of ATPγS is critical for the long-range chemotaxis of microglia, a response that was significantly inhibited in microglia treated with an agent inducing lysosome osmodialysis or in cells derived from mice deficient in Rab 27a (ashen mice), a small GTPase required for the trafficking and exocytosis of secretory lysosomes. These results suggest that microglia respond to extracellular ATP by releasing ATP themselves through lysosomal exocytosis, thereby providing a positive feedback mechanism to generate a long-range extracellular signal for attracting distant microglia to migrate towards and accumulate at the site of injury.