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Highlights • CRISPR/Cas9 induces random deletions in the target region of GABRR2 gene. • Both big and small indels can lead to unexpected high probability of exon truncation/skipping and exon recruitment. • It is the first observation of exon recruitment by CRISPR/Cas9-mediated GABRR2 gene editing. Abstract CRISPR/Cas9 and its variations provide an efficient tool for targeted genome editing. CRISPR/Cas9-based genome editing can induce mutations in genome that has high probability to cause exon truncation or deletion. However, screening mutations in diploid cells is difficult because of two copies of chromosome. It is an important task for determining genotypes in diploid cells subjected to editing before using these cells in gene function study. In this study, we applied CRISPR/Cas9 to edit the GABRR2 gene in mouse retinal ganglion cells to study what exactly happened in two alleles and what real mRNA isoforms formed in diploid cells. A single sgRNA was employed to generate double-strand DNA breaks. PCR sequencing was used for single clone validation in diploid cells subjected to editing. The indels and the corresponding effects at the target locus were further studied at genomic and RNA levels. We observed that CRISPR/Cas9 induces random deletions in the target region of GABRR2 gene, and both big and small indels can lead to unexpected high probability of exon truncation/skipping. In addition, random deletions in genomic region recruited introns to generate new "exon". It is the first observation of exon recruitment by CRISPR/Cas9-mediated GABRR2 gene editing. The observations may offer a reference for the future gene splicing study. [ABSTRACT FROM AUTHOR]

Arsenic (As) is among the most dangerous metalloids and is harmful to human wellbeing. In this laboratory study, Al(III)-modified kapok fibres (Al-Kapok) were used to remove As(V) from water. The sorbent was characterised using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Batch experiments were performed to observe the performance of Al-Kapok in the removal of As(V) and to examine the effects of pH, temperature, adsorbent dose, and coexisting ions on the adsorption process. The surface of the sorbent changed after aluminium modification, and the results of the batch experiments showed that the adsorption of As(V) occurred mainly via endothermic-spontaneous chemisorption at the solution and solid interface of Al-Kapok. The As(V) removal efficiency was approximately 76%–84%, and it was slightly affected at pH levels below 8.0. Further study showed that the maximum adsorption capacity of Al-Kapok for As(V) was 118 μg/g at 30 °C and pH 6, and notable adverse effects were caused by the presence of SO 4 2 − and PO 4 3 − . It was also found that the boundary layer and film diffusion contributed more to As(V) adsorption. After five adsorption/desorption cycles, regeneration recovered approximately 92% of the adsorption capacity of Al-Kapok used. Overall, Al-Kapok appears to be a suitable adsorbent material for the purification of As-contaminated water. [Display omitted] • The adsorption of As(V) on the Al-Kapok is slightly affected by pH at pHs below 8.0 • As(V) adsorption is mainly a chemical process and inhibited by multi-valent anions. • Boundary layer and film diffusion shows more contribution to the adsorption of As(V). • 92% of the Al-Kapok's adsorption capacity could be recovered through regeneration. [ABSTRACT FROM AUTHOR]

Abstract: Recent discovery of biological function of endothelial cell-specific chemotaxic regulator (ECSCR), previously known as endothelial cell-specific molecule 2 (ECSM2), in modulating endothelial cell migration, apoptosis, and angiogenesis, has made it an attractive molecule in vascular research. Thus, identification of splice variants of ECSCR could provide new strategies for better understanding its roles in health and disease. In this study, we performed a series of blast searches on the human EST database with known ECSCR cDNA sequence (Variant 1), and identified additional three splice variants (Variants 2–4). When examining the ECSCR gene in the human genome assemblies, we found a large unknown region between Exons 9 and 11. By PCR amplification and sequencing, we partially mapped Exon 10 within this previously unknown region of the ECSCR gene. Taken together, in addition to previously reported human ECSCR, we identified three novel full-length splice variants potentially encoding different protein isoforms. We further defined a total of twelve exons and nearly all exon–intron boundaries of the gene, of which only eight are annotated in current public databases. Our work provides new information on gene structure and alternative splicing of the human ECSCR, which may imply its functional complexity. This undoubtedly opens new opportunities for future investigation of the biological and pathological significance of these ECSCR splice variants. [Copyright &y& Elsevier]

Food waste and waste paper are the two largest components of municipal solid waste, and many previous studies found that their co-digestion improved methane yield. This study investigated the anaerobic co-digestion of 0–100% food waste with paper food packages on lab-scale with feedstock-to-inoculum (F/I) ratios from 0.5 to 6 (based on volatile solids, VS) and total solids contents from 8% to 28%. In addition to methane yield, volumetric productivity and process economics were also used to evaluate the operating parameters. Results showed that the highest cumulative methane yield of around 530 L/kg-VS feed was obtained from 100% food waste at F/I ratios of 0.5, 1, and 2; the highest volumetric methane productivity of 44.2 L/L work was achieved with 25% food waste at an F/I ratio of 6; and the highest annual net profit was obtained from 75% food waste at an F/I ratio of 2, which also achieved the highest internal rate of return (20.7%) and the shortest payback period (5 years). Addition of waste paper packages to food waste could enhance the digester stability, and it is beneficial to allow certain amount of paper packages and tissues to be collected together with food waste during the initial source separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Mood disorders are a group of psychiatric conditions that represent leading global disease burdens. Increasing evidence from clinical and preclinical studies supports that innate immune system dysfunction plays an important part in the pathophysiology of mood disorders. P2X7 receptor, belonging to the ligand-gated ion channel P2X subfamily of purinergic P2 receptors for extracellular ATP, is highly expressed in immune cells including microglia in the central nervous system (CNS) and has a vital role in mediating innate immune response. The P2X7 receptor is also important in neuron-glia signalling in the CNS. The gene encoding human P2X7 receptor is located in a locus of susceptibility to mood disorders. In this review, we will discuss the recent progress in understanding the role of the P2X7 receptor in the pathogenesis and development of mood disorders and in discovering CNS-penetrable P2X7 antagonists for potential uses in in vivo imaging to monitor brain inflammation and antidepressant therapeutics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal polymeric composites based on pyrimidine-functionalized COFs (covalent organic frameworks) were fabricated. • Fe@COF-Pyr composite possesses good catalytic performance for oxygen evolution reaction. • Au-Pd@COF-Pyr can promote methane oxidation. Functionalized covalent organic frameworks (COFs) materials are used in various fields due to their unique properties. Herein, the reported pyrimidine-functionalized COFs sample named COF-Pyr is selected as the matrix to provide two COFs-based metal composites Fe@COF-Pyr and Au-Pd@COF-Pyr, which are respectively synthesized through metal coordination and in situ reduction reaction. On the one hand, Fe@COF-Pyr used as the electrocatalyst exhibits a good oxygen evolution reaction activity with the overpotential of only 430 mV at a current density of 10 mA cm−2 in the KOH solution (1 M) electrolyte. It is attributed to the large specific surface area (427 m2/g) and abundant catalytic sites of Fe@COF-Pyr, which help to improve the electrochemical performance. On the other hand, Au-Pd@COF-Pyr is an excellent catalyst for methane conversion that the products of the methane oxidation reaction can be obtained under mild reaction conditions. This work not only provides a newfangled notion for the design and preparation of COFs-based metal composites but also broadens the practical application of COFs materials in the domain of catalysis. [ABSTRACT FROM AUTHOR]

Ligand-gated ion channels play a role in mediating fast synaptic transmission for communication between neurons. However, the structural basis for the functional coupling of the binding and pore domains, resulting in channel opening, remains a topic of intense investigation. Here, a series of α7 nicotinic receptor mutants were constructed for expression in cultured mammalian cells, and their single-channel properties were examined using the patch-clamp technique combined with radio ligand binding and the fluorescence staining technique. We demonstrated that the replacement of the four pore-lining residues in the channel domain of the α7 nicotinic receptor with the hydrophilic residue serine prolongs the open-channel lifetime, although the conductance of these mutants decreases. At the coupling interface between the extracellular and transmembrane domains, when the VRW residues in the Cys-loop were substituted with the corresponding residues (i.e., IYN) in the 5-HT 3A receptor, the single-channel activity elicited by acetylcholine is impaired. This effect occurred despite the expression of the mutant receptors on the cell surface and despite the fact that the apparent K d values were much lower than those of the wild-type α7 receptor. When we further lowered the channel-gating barrier of this chimera to enhance the open-channel probability, the loss of function was rescued. Overall, we explored the microscopic mechanisms underlying the interplay between the channel domains and the coupling interface that affect the channel activity, and we generated an allosteric gating model for the α7 receptor. This model shows that the gating machinery and coupling assembly codetermine the single-channel gating kinetics. These results likely apply to all channels in the Cys-loop receptor family. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new fluorescent covalent organic frameworks was synthesized. • N , O -bidentate ligation was be used to combine difluoroboron. • 50% B-COF exhibited red fluorescence under ultraviolet excitation. The multi-dentate chelate ligands containing N and O atoms have good chelating ability to boron trifluoride and their complexes show good fluorescence properties. In this work, a fluorescent covalent organic framework (COF) with good crystallinity and porosity, 50% B-COF, was successfully synthesized by coordination of starting COFs 50% COF-OH with boron trifluoride diethyl etherate via N, O-bidentate ligation. Imine bonds are highly polarized. The coordination of nitrogen and boron changes the electron cloud distribution of imine bonds, causing the non-fluorescent 50% COF-OH to be transformed into fluorescent 50% B-COF. 50% B-COF exhibited red fluorescence under ultraviolet excitation. This work provides a new strategy for the design of fluorescent COFs. [ABSTRACT FROM AUTHOR]

Abstract: Estrogen has great potential as a therapeutic agent in focal ischemic brain injury. Amino acids as energy resources and neurotransmitters in the central nervous system are crucial for proper neuronal function and excitability. The proton-coupled amino acid transporter PAT1 has clear potential in drug absorption. In this paper, human brain PAT1 was cloned and expressed in Xenopus oocytes. The effects of estradiol on the activity of PAT1 were investigated. Glycine-induced membrane currents mediated by PAT1 were measured using the two-electrode voltage clamp technique. The amplitude of the glycine-elicited current was decreased progressively with increasing concentrations of β-estradiol. A concentration-dependent outwards current of PAT1 was also detected by the presence of β-estradiol. We conclude that estrogen attenuates the activity of PAT1 by directly closing PAT1 channel. Our results may provide an additional mechanism for estrogen on neurotransmission and neuronal metabolism during ischemic injury. [Copyright &y& Elsevier]