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The performance of zeolitic imidazolate framework-8 (ZIF-8) for CO₂ capture under three different conditions (wetted ZIF-8, ZIF-8/water slurry, and ZIF-8/water–glycol slurry) was systemically investigated. This investigation included the study of the pore structure stability of ZIF-8 by using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and Raman detection technologies. Our results show that the CO₂ adsorption ability of ZIF-8 could be substantially increased under the existence of liquid water. However, the structure characterization of the recovered ZIF-8 showed an irreversible change of its framework, which occurs during the CO₂ capture process. It was found that there is an irreversible chemical reaction among ZIF-8, water, and CO₂, which creates both zinc carbonate (or zinc carbonate hydroxides) and single 2-methylimidazole crystals, and therefore the pore structure of ZIF-8 collapses. It is suggested therefore that care must be taken when using ZIF-8 or products containing ZIF-8 for gas capture, gas separation, or other applications where both water and acid gases coexist

Mutations in the Human naked cuticle Homolog NKD1 Found in Colorectal Cancer Alter Wnt/Dvl/β-Catenin Signaling

BACKGROUND:Mutation of Wnt signal antagonists Apc or Axin activates beta-catenin signaling in many cancers including the majority of human colorectal adenocarcinomas. The phenotype of apc or axin mutation in the fruit fly Drosophila melanogaster is strikingly similar to that caused by mutation in the segment-polarity gene, naked cuticle (nkd). Nkd inhibits Wnt signaling by binding to the Dishevelled (Dsh/Dvl) family of scaffold proteins that link Wnt receptor activation to beta-catenin accumulation and TCF-dependent transcription, but human NKD genes have yet to be directly implicated in cancer. METHODOLOGY/PRINCIPAL FINDINGS:We identify for the first time mutations in NKD1--one of two human nkd homologs--in a subset of DNA mismatch repair-deficient colorectal tumors that are not known to harbor mutations in other Wnt-pathway genes. The mutant Nkd1 proteins are defective at inhibiting Wnt signaling; in addition, the mutant Nkd1 proteins stabilize beta-catenin and promote cell proliferation, in part due to a reduced ability of each mutant Nkd1 protein to bind and destabilize Dvl proteins. CONCLUSIONS/SIGNIFICANCE:Our data raise the hypothesis that specific NKD1 mutations promote Wnt-dependent tumorigenesis in a subset of DNA mismatch-repair-deficient colorectal adenocarcinomas and possibly other Wnt-signal driven human cancers

Aberrant Expression and Subcellular Localization of PER2 Promote the Progression of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma, one of the most prevalent cancer types in the world, has been confirmed under the influence of a key circadian gene, PER2, whose role has been identified in the development of some other types of cancers. However, the mechanism through which PER2 regulates the progress of OSCC remains largely unknown. In this study, we showed that besides the abnormal expression and subcellular localization of PER2 observed in OSCC tissues and cells as expected, these anomalous changes also existed in the adjacent noncancerous tissues, which was a novel finding in our research. The phase of PER2 rhythmic expression pattern in OSCC cells was later than that in oral keratinocytes in the protein level. In addition, we demonstrated that PER2 played as a resistant factor in the development of OSCC by upregulating TP53 and inhibiting epithelial-mesenchymal transition in vitro and in vivo. Taken together, our results identified that the development of OSCC is closely associated with PER2, the aberrant expression and subcellular localization of which facilitates the malignant progress

Inter-individual heterogeneity of functional brain networks in children with autism spectrum disorder

Abstract Background Autism spectrum disorder (ASD) is a neurodevelopmental disorder with considerable clinical heterogeneity. This study aimed to explore the heterogeneity of ASD based on inter-individual heterogeneity of functional brain networks. Methods Resting-state functional magnetic resonance imaging data from the Autism Brain Imaging Data Exchange database were used in this study for 105 children with ASD and 102 demographically matched typical controls (TC) children. Functional connectivity (FC) networks were first obtained for ASD and TC groups, and inter-individual deviation of functional connectivity (IDFC) from the TC group was then calculated for each individual with ASD. A k-means clustering algorithm was used to obtain ASD subtypes based on IDFC patterns. The FC patterns were further compared between ASD subtypes and the TC group from the brain region, network, and whole-brain levels. The relationship between IDFC and the severity of clinical symptoms of ASD for ASD subtypes was also analyzed using a support vector regression model. Results Two ASD subtypes were identified based on the IDFC patterns. Compared with the TC group, the ASD subtype 1 group exhibited a hypoconnectivity pattern and the ASD subtype 2 group exhibited a hyperconnectivity pattern. IDFC for ASD subtype 1 and subtype 2 was found to predict the severity of social communication impairments and the severity of restricted and repetitive behaviors in ASD, respectively. Limitations Only male children were selected for this study, which limits the ability to study the effects of gender and development on ASD heterogeneity. Conclusions These results suggest the existence of subtypes with different FC patterns in ASD and provide insight into the complex pathophysiological mechanism of clinical manifestations of ASD

A comparative analysis for the volatile compounds of various Chinese dark teas using combinatory metabolomics and fungal solid-state fermentation

A total of 98 compounds including 20 aldehydes, eight arenes, six acids, 17 alcohols, 13 ketones, nine esters, nine methoxyphenolics, three alkenes, seven alkanes, and six other components were tentatively identified in six Chinese dark teas (CDTs) using gas chromatography–mass spectrometry. Multivariate statistical analysis revealed that dark teas from Yunnan and Guangxi provinces could be classified into one group, and other CDTs belonged to the other cluster. The diagnostic volatile compounds being responsible for CDTs' discrimination were observed as (E,E)-2,4-decadienal, methoxyphenolics, geraniol, α-terpineol, 2,4-heptadienal, cis-jasmone, linalool oxides, and 2-nonenal. Furthermore, mature tea leaves were separately fermented using Eurotium cristatum and Aspergillus niger. The results showed that E. cristatum increased the contents of cis-jasmone, α-terpineol, ß-ionone, nonanal, and 2-pentylfuran, whereas A. niger advanced the levels of geraniol, linalool oxides, 9,12-octadecadienoic acid, and ß-ionone after short-term fermentation. Fungus species may contribute to forming the flavor of Chinese dark teas by affecting the volatile compounds during postfermentation

luxS contributes to intramacrophage survival of Streptococcus agalactiae by positively affecting the expression of fruRKI operon

Abstract The LuxS quorum sensing system is a widespread system employed by many bacteria for cell-to-cell communication. The luxS gene has been demonstrated to play a crucial role in intramacrophage survival of piscine Streptococcus agalactiae, but the underlying mechanism remains largely unknown. In this study, transcriptome analysis, followed by the luxS gene deletion and subsequent functional studies, confirmed that impaired bacterial survival inside macrophages due to the inactivation of luxS was associated with reduced transcription of the fruRKI operon, encoding the fructose-specific phosphotransferase system. Further, luxS was determined not to enhance the transcription of fruRKI operon by binding its promoter, but to upregulate the expression of this operon via affecting the binding ability of catabolite control protein A (CcpA) to the catabolite responsive element (cre) in the promoter of fruRKI. Collectively, our study identifies a novel and previously unappreciated role for luxS in bacterial intracellular survival, which may give a more thorough understanding of the immune evasion mechanism in S. agalactiae

Effects of Combined Sorbitan Monolaurate Anti-Agglomerants on Viscosity of Water-in-Oil Emulsion and Natural Gas Hydrate Slurry

Hydrate plugging is the major challenge in the flow assurance of deep-sea pipelines. For water-in-oil emulsions, this risk could be significantly reduced with the addition of anti-agglomerants (AAs). Hydrates often form from water-in-oil emulsions and the measurement of emulsion and slurry viscosity constitutes the basis for the application of hydrate slurry flow technology. In this work, using a novel high-pressure viscometer, emulsion and slurry viscosity with different AAs for water content ranging from 5% to 30% was obtained. The viscosity-temperature curves of emulsions were determined and correlated. The variation of system viscosity during hydrate formation from water-in-oil emulsions was examined, the sensitivity of stable slurry viscosity to water cut and the effects of temperature on annealed slurry viscosity were investigated. The results indicated that the variation of viscosity during hydrate formation relies on the conversion ratio. It also implied that the sensitivity of slurry viscosity to change in its water cut or temperature was reduced with AA addition

Polyoxometalate-Based Radiosensitization Platform for Treating Hypoxic Tumors by Attenuating Radioresistance and Enhancing Radiation Response

Radioresistance is one of the undesirable impediments in hypoxic tumors, which sharply diminishes the therapeutic effectiveness of radiotherapy and eventually results in the failure of their treatments. An attractive strategy for attenuating radioresistance is developing an ideal radiosensitization system with appreciable radiosensitization capacity to attenuate tumor hypoxia and reinforce radiotherapy response in hypoxic tumors. Therefore, we describe the development of Gd-containing polyoxometalates-conjugated chitosan (GdW10@CS nanosphere) as a radio sensitization system for simultaneous extrinsic and intrinsic radiosensitization, by generating an overabundance of cytotoxic reactive oxygen species (ROS) using high-energy X-ray stimulation and mediating the hypoxia-inducible factor-la (HIF-la) siRNA to down-regulate HIF-la expression and suppress broken double-stranded DNA self-healing. Most importantly, the GdW10@CS nanospheres have the capacity to promote the exhaustion of intracellular glutathione (reduced GSH) by synergy W6+-triggered GSH oxidation for sufficient ROS generation, thereby facilitating the therapeutic efficiency of radiotherapy. As a result, the as-synthesized GdW10@CS nanosphere can overcome radioresistance of hypoxic tumors through a simultaneous extrinsic and intrinsic strategy to improve radiosensitivity. We have demonstrated GdW10@CS nanospheres with special radiosensitization behavior, which provides a versatile approach to solve the critical radioresistance issue of hypoxic tumors.</p

Genesis of electron deficient Pt1(0) in PDMS-PEG aggregates

While numerous single atoms stabilized by support surfaces have been reported, the synthesis of in-situ reduced discrete metal atoms weakly coordinated and stabilized in liquid media is a more challenging goal. We report the genesis of mononuclear electron deficient Pt-1(0) by reducing H2PtCl6 in liquid polydimethylsiloxane-polyethylene glycol (PDMS-PEG) (Pt-1@PDMS-PEG). UV-Vis, far-IR, and X-ray photoelectron spectroscopies evidence the reduction of H2PtCl6. CO infrared, and Pt-195 and C-13 NMR spectroscopies provide strong evidence of Pt-1(0), existing as a pseudo-octahedral structure of ((ROR2)-O-1)(2)Pt(0)Cl2H2 (R-1 and R-2 are H, C, or Si groups accordingly). The weakly coordinated ((ROR2)-O-1)(2)Pt(0)Cl2H2 structure and electron deficient Pt-1(0) have been validated by comparing experimental and DFT calculated Pt-195 NMR spectra. The H+ in protic state and the Cl- together resemble HCl as the weak coordination. Neutralization by a base causes the formation of Pt nanoparticles. The Pt-1@PDMS-PEG shows ultrahigh activity in olefin hydrosilylation with excellent terminal adducts selectivity