Nanosized Pt, PtRu, and Ru particles were prepared by a novel process, the hydrosilylation reaction. The hydrosilylation reaction is an effective method of preparation not only for Pt particles but ...also for other metal colloids, such as Ru. Vulcan XC-72 was selected as catalyst support for Pt, PtRu, and Ru colloids, and TEM investigations showed nanoscale particles and narrow size distribution for both supported and unsupported metals. All Pt and Pt-rich catalysts showed the X-ray diffraction pattern of a face-centered cubic (fcc) crystal structure, whereas the Ru and Ru-rich alloys were more typical of a hexagonal close-packed (hcp) structure. As evidenced by XPS, most Pt and Ru atoms in the nanoparticles were zerovalent, except a trace of oxidation-state metals. The electrooxidation of liquid methanol on these catalysts was investigated at room temperature by cyclic voltammetry and chronoamperometry. The results concluded that some alloy catalysts showed higher catalytic activities and better CO tolerance than the Pt-only catalyst; Pt56Ru44/C have displayed the best electrocatalytic performance among all carbon-supported catalysts.
Liquid Shaping Based on Liquid Pancakes Li, Xiaoguang; Shi, Haixiao; Wang, Yiqi ...
Advanced materials interfaces,
January 23, 2018, Volume:
5, Issue:
2
Journal Article
Peer reviewed
Liquid marbles with quasi‐spherical shapes have great application potential as miniature containers. Recently, their shape modification is investigated, revealing great possibilities in broadening ...the uses for such containers. Current methods have demonstrated shape designability, but fine control of the final shape, important in applications, has remained a problem. Here, a facile method, based on a gravity‐induced liquid pancake coated with a nanoparticle monolayer, is proposed that allows continuous segmentation of the liquid. As a result, well‐shaped liquids, as structured liquid marbles with accurate target profiles, are formed. The density of interfacial particles is found to determine the segmentation feasibility and to affect the shaped liquid profile. Additionally, the maximum bifurcation is positively related to the initial particle density. This work basically achieves fine control of the liquid shape, enhancing the foundation for the development of liquid‐based smart containers.
Water in milliliter order forms a pancake shape on a superhydrophobic surface. Subjecting such a pancake to interfacial jamming of nanoparticles allows a segmenting manipulation of the coated liquid pancake. Based on this mechanism, liquid shaping is realized with the resulting product, as liquid plasticine, characterized with accurate profile, large size, and high transparency.
Aim
Approximately a third of patients with schizophrenia fail to adequately respond to antipsychotic medications, a condition known as treatment resistance (TR). We aimed to assess cognitive and ...cortical thickness deficits and their relationship to TR in schizophrenia.
Method
We recruited patients with schizophrenia (n = 127), including patients at treatment initiation (n = 45), treatment‐responsive patients (n = 40) and TR patients (n = 42), and healthy controls (n = 83). Clinical symptoms, neurocognitive function, and structural images were assessed. We performed group comparisons, and explored association of cortical thickness and cognition with TR.
Results
The TR patients showed significantly more severe clinical symptoms and cognitive impairment relative to the treatment‐responsive group. Compared to healthy controls, 56 of 68 brain regions showed significantly reduced cortical thickness in patients with schizophrenia. Reductions in five regions were significantly associated with TR (reduction in TR relative to treatment‐responsive patients), i.e. in the right caudal middle frontal gyrus, superior frontal cortex, fusiform gyrus, pars opercularis of the inferior frontal cortex, and supramarginal cortex. Cognition deficits were also significantly correlated with cortical thickness in these five regions in patients with schizophrenia. Cortical thickness of the right caudal middle frontal gyrus, superior frontal cortex and pars opercularis of the inferior frontal cortex also significantly mediated effects of cognitive deficits on TR.
Conclusion
Treatment resistance in schizophrenia was associated with reduced thickness in the right caudal middle frontal gyrus, superior frontal cortex, fusiform gyrus, pars opercularis of the inferior frontal cortex, and supramarginal cortex. Cortical abnormalities further mediate cognitive deficits known to be associated with TR.
The green alga Chlorella zofingiensis can accumulate high level of oleic acid (OA, C18:1∆⁹) rich oils in response to stress conditions. To understand the regulation of biosynthesis of fatty acid in ...particular OA at the molecular level, we cloned and characterized the stearoyl acyl carrier protein (ACP) desaturase (SAD) responsible for OA formation through desaturation of stearic acid (C18:0) from C. zofingiensis. Southern blot indicated that the C. zofingiensis genome contained a single copy of SAD, from which the deduced amino acid sequence shared high identity to the corresponding homologs from other microalgae and higher plants. The desaturation activity of SAD was demonstrated in vitro using C18:0-ACP as a substrate. Stress conditions such as high light (HL), nitrogen deficiency (N⁻), or combination of HL and N⁻ (HL + N⁻) drastically up-regulated the transcripts of biotin carboxylase (BC, a subunit of ACCase) and SAD, and therefore induced considerably the cellular accumulation of total fatty acids including OA. Glucose (50 mM) gave rise to the similar upregulation of the two genes and induction of fatty acid accumulation. The accumulation of intracellular reactive oxygen species was found to be associated with the upregulation of genes. This is the first report of characterization of Chlorella-derived SAD and the results may contribute to understanding of the mechanisms involved in fatty acid/lipid biosynthesis in microalgae.
Heterotopic ossification (HO) occurs when bone forms within non-ossifying tissues, such as in muscle. Palovarotene, an activator of retinoic acid receptor γ (RAR-γ), has been shown to inhibit the ...formation of ectopic bone in HO model mice, but its specific mechanism of action remains unclear. This study will explore the target and molecular mechanism of Palovarotene's action on HO by network pharmacology study. We collected the relevant targets of Palovarotene and HO from the database, obtained the potential targets of Palovarotene acting on HO through Venn analysis, and constructed the protein-protein interaction (PPI) network. Then, Gene Ontology (GO) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment Analysis and Module-based Network Analysis were performed for potential targets, and in addition, PPI Network Topology Analysis and Gene-Phenotype Correlation Analysis were performed. The results suggested that MAPK1, MDM2, and other targets as well as P53 signaling pathway and PI3K-Akt signaling pathway may be closely related to Palovarotene treatment of HO. We carried out verification experiments to confirm our finding, alkaline phosphatase and alizarin red staining
and Micro-CT as well as hematoxylin-eosin staining
were performed to verify treatment for HO of Palovarotene, reverse transcription polymerase chain reaction was also used to explore the transcription changes of MAPK1, MDM2, and osteogenic genes. This study systematically elucidated the possible mechanism of Palovarotene in the treatment of HO through network pharmacology study, revealing a new direction for the further application of Palovarotene in the treatment of HO.
β-Carotene ketolase (BKT) catalyzes the ratelimiting steps for the biosynthesis of astaxanthin. Several bkt genes have been isolated and explored to modify plant carotenoids to astaxanthin with ...limited success. In this study, five algal BKT cDNAs were isolated and characterized for the engineering of high-yield astaxanthin in plants. The products of the cDNAs showed high similarity in sequence and enzymatic activity of converting β-carotene into canthaxanthin. However, the enzymes exhibited extremely different activities in converting zeaxanthin into astaxanthin. Chlamydomonas reinhardtii BKT showed the highest conversion rate (ca 85 %), whereas, Neochloris wimmeri BKT exhibited very poor activity of ketolating zeaxanthin. Expression of reinhardtii BKT in tobacco led to a twofold increase of total carotenoids in the leaves with astaxanthin being the predominant. The bkt genes described here provide a valuable resource for metabolic engineering of plants as cell factories for astaxanthin production.
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► Microbore-scale (1mm i.d.) anion-exchange monolithic column. ► Potentially preparative applications. ► Separation of oligodeoxythymidylic acids and DNA fragments.
In this paper, we ...report on the preparation of a microbore-scale (1mm i.d.) anion-exchange monolithic column suitable not only for analytical purposes but also for potentially preparative applications. In order to meet the conflicting requirements of high permeability and good mechanical strength, the following two-step procedure was applied. First, an epoxy-containing monolith was synthesized by in situ copolymerization of glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) within the confines of a silicosteel tubing of 1.02mm i.d. and 1/16″ o.d. in the presence of a ternary porogenic mixture of 1-propanol, 1,4-butanediol, and water. The monolithic matrix was subsequently converted into weak anion-exchanger via the ring-opening reaction of epoxy group with diethyl amine. The dynamic binding capacity was 21.4mgmL−1 for bovine serum albumin (BSA) at 10% breakthrough. The morphology and porous structure of this monolith were assessed by scanning electron microscope (SEM) and inverse size exclusion chromatography (ISEC). To optimize the separation efficiency, the effects of various chromatographic parameters upon the separation of DNA fragments were investigated. The resulting monolithic anion exchanger demonstrated good potential for the separation of both single- and double-stranded DNA molecules using a gradient elution with NaCl in Tris–HCl buffer (20mM). Oligodeoxythymidylic acids (dT12–dT18) were successfully resolved at pH 8, while the fragments of 20bp DNA ladder, 100bp DNA ladder, and pBR322-HaeIII digest were efficiently separated at pH 9.
Abstract Background Increasing evidence suggested that immune abnormalities involved in the pathophysiology of schizophrenia. However, the relationship between immunity and clinical features has not ...been clarified. The aim of this study was to measure the plasma levels of tumor necrosis factor alpha (TNF-α) and soluble TNF-α receptor 1 (sTNF-α R1) and to investigate their association with agitation in first episode patients with schizophrenia (FEPS). Methods The plasma TNF-α and sTNF-α R1 levels were measured using sandwich enzyme-linked immunosorbent assay (ELISA) in the FEPS with ( n = 36) and without agitation ( n = 49) symptoms, and healthy controls (HCs, n = 54). The psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS), and the agitation symptoms were evaluated by the PANSS excitatory component (PANSS-EC). Results The plasma TNF-α levels in patients with and without agitation symptoms were significantly higher than those in HCs. The patients with agitation had significantly higher plasma TNF-α levels compared to the patients without agitation. There were no significant differences in the sTNF-α R1 levels among the three groups. Furthermore, the plasma TNF-α levels were positively correlated with the PANSS total score, Positive and General psychopathological subscores, and PANSS-EC score in the FEPS, but the relationships were not found for the plasma sTNF-α R1 levels. Conclusions These results suggested that TNF-α might play an important role in the onset and development of agitation symptoms of schizophrenia.
A number of tryptophan metabolites known to be neuroactive have been examined for their potential associations with cognitive deficits in schizophrenia. Among these metabolites, kynurenic acid ...(KYNA), 5-hydroxyindole (5-HI), and quinolinic acid (QUIN) are documented in their diverse effects on α-7 nicotinic acetylcholine receptor (α7nAChR) and/or N-methyl-D-aspartate receptor (NMDAR), two of the receptor types thought to contribute to cognitive impairment in schizophrenia. In this study, serum levels of KYNA, 5-HI, and QUIN were measured in 195 patients with schizophrenia and in 70 healthy controls using liquid chromatography-tandem mass spectrometry; cognitive performance in MATRICS Consensus Cognitive Battery and cortical thickness measured by magnetic resonance imaging were obtained. Patients with schizophrenia had significantly lower serum KYNA (p < 0.001) and QUIN (p = 0.02) levels, and increased 5-HI/KYNA (p < 0.001) and QUIN/KYNA ratios (p < 0.001) compared with healthy controls. Multiple linear regression showed that working memory was positively correlated with serum 5-HI levels (t = 2.10, p = 0.04), but inversely correlated with KYNA concentrations (t = -2.01, p = 0.05) in patients. Patients with high 5-HI and low KYNA had better working memory than other subgroups (p = 0.01). Higher 5-HI levels were associated with thicker left lateral orbitofrontal cortex (t = 3.71, p = 2.94 × 10
) in patients. The different effects of 5-HI and KYNA on working memory may appear consistent with their opposite receptor level mechanisms. Our findings appear to provide a new insight into the dynamic roles of tryptophan pathway metabolites on cognition, which may benefit novel therapeutic development that targets cognitive impairment in schizophrenia.
The biosynthesis of the ketocarotenoid astaxanthin is a subject of scientific and industrial interest. The unicellular green alga Chlorella zofingiensis Dönz is able to grow and accumulate ...astaxanthin in the dark with exogenous glucose as sole carbon and energy source. In this study, the transcription of β-carotenoid ketolase (BKT) and β-carotenoid hydroxylase (CHYb) genes were surveyed to reveal the regulation of astaxanthin biosynthesis in dark-grown Chlorella zofingiensis. Coupled with glucose analogs and the hexokinase inhibitor glucosamine, we found that phosphorylation of glucose (glucose sensing) was essential to the increased transcription of BKT and CHYb genes and the accumulation of astaxanthin in the dark-grown cells. However, phosphorylation of glucose per se only up-regulated the transcription of CHYb and stimulated the synthesis of zeaxanthin. Blockage of the mitochondrial alternative pathway eliminated the glucose effects on the increased transcription of BKT and astaxanthin accumulation, suggesting that signals from alternative pathway was involved in the up-regulation of BKT transcription. In addition, citrate was shown to up-regulate the transcription of BKT independent of reactive oxygen species formation. Taken altogether, we conclude that in dark-grown Chlorella zofingiensis, the transcription of BKT and CHYb genes are differently regulated by the metabolism of glucose, through which the biosynthesis of astaxanthin is regulated.
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