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α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid glutamate receptors (AMPARs) enable rapid excitatory synaptic transmission by localizing to the postsynaptic density of glutamatergic spines. AMPARs possess large extracellular N-terminal domains (NTDs), which are crucial for AMPAR clustering at synaptic sites. However, the dynamics of NTDs and the molecular mechanism governing their synaptic clustering remain elusive. Here, we employed high-speed atomic force microscopy (HS-AFM) to directly visualize the conformational dynamics of NTDs in the GluA2 subunit complexed with TARP γ2 in lipid environments. HS-AFM videos of GluA2-γ2 in the resting and activated/open states revealed fluctuations in NTD dimers. Conversely, in the desensitized/closed state, the two NTD dimers adopted a separated conformation with less fluctuation. Notably, we observed individual NTD dimers transitioning into monomers, with extended monomeric states in the activated/open state. Molecular dynamics simulations provided further support, confirming the energetic stability of the monomeric NTD states within lipids. This NTD-dimer splitting resulted in subunit exchange between the receptors and increased the number of interaction sites with synaptic protein neuronal pentraxin 1 (NP1). Moreover, our HS-AFM studies revealed that NP1 forms a ring-shaped octamer through N-terminal disulfide bonds and binds to the tip of the NTD. These findings suggest a molecular mechanism in which NP1, upon forming an octamer, is secreted into the synaptic region and binds to the tip of the GluA2 NTD, thereby bridging and clustering multiple AMPARs. Thus, our findings illuminate the critical role of NTD dynamics in the synaptic clustering of AMPARs and contribute valuable insights into the fundamental processes of synaptic transmission.

Neuroinflammation is a common feature in various neurological disorders. Understanding neuroinflammation and neuro-immune interactions is of significant importance. However, the intercellular interactions in the inflammatory model are intricate. Microfluidic chips, with their complex micrometer-scale structures and real-time observation capabilities, offer unique advantages in tackling these complexities compared to other techniques. In this study, microfluidic chip technology was used to construct a microarray physical barrier structure with 15 μm spacing, providing well-defined cell growth areas and clearly delineated interaction channels. Moreover, an innovative hydrophilic treatment process on the glass surface facilitated long-term co-culture of cells. The developed neuroinflammation model on the chip revealed that SH-SY5Y cytotoxicity was predominantly influenced by co-cultured THP-1 cells. The co-culture model fostered complex interactions that may exacerbate cytotoxicity, including irregular morphological changes of cells, cell viability reduction, THP-1 cell migration, and the release of inflammatory factors. The integration of the combinatorial cell–cell interaction chip not only offers a clear imaging detection platform but also provides diverse data on cell migration distance, migration direction, and migration angle. Furthermore, the designed ample space for cell culture, along with microscale channels with fluid characteristics, allow for the study of inflammatory factor distribution patterns on the chip, offering vital theoretical data on biological relevance that conventional experiments cannot achieve. The fabricated user-friendly, reusable, and durable co-culture chip serves as a valuable in vitrotool, providing an intuitive platform for gaining insights into the complex mechanisms underlying neuroinflammation and other interacting models.

Negative temperature coefficient (NTC) thermistor plays a crucial role in science research and engineering applications for precise temperature monitoring. Although great progress has been achieved in NTC materials, enhancing sensitivity and maintaining this high sensitivity along with linearity across extensive temperature ranges remain a significant challenge. In this study, we introduce a diamond-based thermistor (DT) characterized by its outstanding sensitivity, swift response time, and broad temperature monitoring capabilities. The temperature constant Bfor this DT, measured from 30 to 300°C (B30/300), achieves an exceptional value of 8012 K, which notably exceeds the temperature sensing capabilities of previously reported NTC thermistors within this extensive range. Moreover, diamond’s unique thermal conductivity and stability significantly boost the response speed and durability of the DT, offering substantial advantages over traditional ceramic thermistors. The enhanced temperature-sensitive properties of the DT are attributed to the presence of impurity elements in polycrystalline diamond. Impedance analysis indicates a hopping conduction mechanism, likely involving C-H or C-N dipoles at the diamond grain boundaries. This study marks a significant leap forward in diamond thermistor technology and sheds light on the mechanisms of thermal active conduction in diamond materials.

Avian reovirus (ARV) is the causative agent of avian viral arthritis and causes significant economic losses to the global poultry industry. For clinical diagnosis, detecting ARV-specific antibodies is crucial. We successfully expressed the ARV-σC protein in insect cells using the baculovirus expression vector system, achieving an expression level of approximately 200 mg/L. We developed an indirect enzyme-linked immunosorbent assay (iELISA) using the ARV-σC protein as a coating antigen to detect antibodies against it. The inter-batch and intrabatch coefficients of iELISA variation were less than 10%. Its sensitivity (1:12,800 diluted in serum) was 4 times higher than that of the indirect immunofluorescence assay (IFA; 1:3200 diluted in serum), and it showed no cross-reactivity with antibodies against other common avian viruses (such as Infectious bursal disease virus, Newcastle disease virus). The practicality of the iELISA was further evaluated using clinical samples. 300 clinical sera from chickens vaccinated with the ARV attenuated vaccine and 20 SPF sera were tested using both the iELISA and the IFA, demonstrating a 100% conformity rate. In conclusion, these results suggest that the iELISA developed in this study is a rapid, sensitive, and specific method that could serve as an effective diagnostic tool for monitoring and controlling avian viral arthritis.

[Display omitted] • A family of novel Co-Ta-B-Si bulk metallic glasses (BMGs) was developed. • The BMGs exhibit both high strength above 5.5 GPa and large plasticity up to 6.4 %. • The BMGs show the enhancement of glass-forming ability (GFA: up to 4 mm). • The improvement of plasticity and GFA were explained by calculated analysis. • A self-organization behavior of shear bands is liable for the increase in plastic. Development of advanced metals materials with ultrahigh strength, large plasticity and high thermostability is one of the most attractive aims for materials researchers. Co-based bulk metallic glasses (BMGs) with the highest strength (up to 6 GPa) and special strength (up to 650 Nm/g) among all of metals materials so far we known have received extensive attentions. In this paper, a family of Co-Ta-B-Si BMGs with high glass-transition temperature (above 870 K), large compressive plasticity (up to 6.4 %) and high strength (above 5.5 GPa), and high glass-forming ability (the critical diameter, D c : up to 4 mm) was developed by accurately tuning metalloid element contents of Si and B in the parental alloy of Co 55 Ta 10 B 35. The changes of glass formation and plasticity caused by the adjustment of the constituent metalloid elements were evaluated by the combination of experimental and calculated results. The reason for the significant improvement of plastic deformation is revealed by the analysis of the self-organization behaviors of high-density shear bands. [ABSTRACT FROM AUTHOR]

Peptide mapping with mass spectrometry (MS) detection is a powerful technique routinely used for interrogating physicochemical properties of proteins. Peptide mapping benefits from an efficient front-end separation to increase selectivity and reduce complexity prior to MS detection. The most commonly used method for peptide mapping is based on reverse phase liquid chromatography with mass spectrometry. Capillary zone electrophoresis with mass spectrometry (CZE-MS) is an orthogonal technique with growing attention for peptide mapping of biotherapeutic proteins due to its high efficiency and sensitivity. However, that growth has been slow due to poorer peptide resolution and method robustness compared to RPLC. Here we present results from optimization of CZE-MS peptide mapping separation using mixed aqueous–aprotic dipolar solvent (N,N-dimethylacetamide (DMA) and N,N-dimethylformamide (DMF), as the background electrolyte (BGE) to improve the separation performance. Addition of DMA or DMF to the BGE impacts separation selectivity through differential change in pKaof the peptides. The CZE-MS peptide mapping method with the modified BGE produced significant improvement in resolution over the conventional CZE-MS methods. The method was evaluated with both sheathless and sheathflow CE-MS ion sources.

This study aimed to evaluate the effects of capelin roe phospholipid (CPL) on lipid accumulation, fatty acid profile, oxidative stress, and changes in target macromolecular structure in HepG2 cells using multidimensional hyperspectral technique. The results showed that CPL significantly inhibited oleic acid-induced accumulation of intracellular lipids and increased the activity of intracellular antioxidant enzymes (CAT, GSH-Px, SOD). The control and CPL-treated groups promoted accumulation of unsaturated fatty acids and reduced deposition of saturated fatty acids. The therapeutic effects of CPL positively correlated with its concentration. Fourier transform infrared spectroscopy and two-dimensional correlation infrared analysis indicated that CPL decreased the relative contents of intracellular carbohydrate, nucleic acid, -CH2-, and ν(C=O)/νas(CH2+CH3), and maintained the order of intracellular protein structure. Fourier transform infrared spectroscopy could be used for label-free cell sorting. This work provided a direction for the subsequent development of functional lipids in aquaculture.

Reversed phase liquid chromatography with mass spectrometry (RPLC-MS) peptide mapping is routinely used for interrogating molecular and structural attributes such as amino acid composition, sequence variants, and post-translational modifications (PTMs) in antibody-derived therapeutics. RPLC has some limitations that often impact the analysis of certain peptides including large hydrophobic peptides, hydrophilic di-/tripeptides and glycopeptides. Capillary zone electrophoresis with mass spectrometry (CZE-MS) has great potential for peptide mapping due to high efficiency and outstanding sensitivity. In this report we demonstrate the utility of CZE-MS as an orthogonal and complementary technique to RPLC-MS for peptide mapping analyses of antibody–drug conjugates (ADCs) and their parent antibodies. This work is based on high-resolution CZE-MS separation recently developed in our group, where a mixed aqueous–organic solvent system containing N,N-dimethylacetamide (DMA) or N,N-dimethylformamide (DMF) was used to improve the separation selectivity. The results described here show several advantages of CZE-MS for the analysis of small hydrophilic di-/tripeptides, large hydrophobic peptides, glycopeptides, and hydrophobic drug-linked peptides.

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We used reversed-phase liquid chromatography to separate the yeast proteome into 23 fractions. These fractions were then analyzed using capillary zone electrophoresis (CZE) coupled to a Q-Exactive HF mass spectrometer using an electrokinetically pumped sheath flow interface. The parameters of the mass spectrometer were first optimized for top-down proteomics using a mixture of seven model proteins; we observed that intact protein mode with a trapping pressure of 0.2 and normalized collision energy of 20% produced the highest intact protein signals and most protein identifications. Then, we applied the optimized parameters for analysis of the fractionated yeast proteome. From this, 580 proteoforms and 180 protein groups were identified via database searching of the MS/MS spectra. This number of proteoform identifications is two times larger than that of previous CZE-MS/MS studies. An additional 3,243 protein species were detected based on the parent ion spectra. Post-translational modifications including N-terminal acetylation, signal peptide removal, and oxidation were identified.

Expression of chloride channel 1(CLCN1/ClC-1) in skeletal muscle is driven by alternative splicing, a process regulated in part by RNA-binding protein families MBNL and CELF. Aberrant splicing of CLCN1produces many mRNAs, which were translated into inactive proteins, resulting in myotonia in myotonic dystrophy (DM), a genetic disorder caused by the expansion of a CTG or CCTG repeat. This increase in abnormal splicing variants containing exons 6B, 7A or the insertion of a TAG stop codon just before exon 7 leads to a decrease in expression of the normal splice pattern. The majority of studies examining splicing in CLCN1have been performed using mouse Clcn1, as have investigations into the activation and suppression of normal splicing variant expression by MBNL1-3and CELF3–6, respectively. In contrast, examinations of human CLCN1have been less common due to the greater complexity of splicing patterns. Here, we constructed a minigene containing CLCN1exons 5–7 and established a novel assay system to quantify the expression of the normal splicing variant of CLCN1using real-time RT-PCR. Antisense oligonucleotides could promote normal CLCN1alternative splicing but the effective sequence was different from that of Clcn1. This result differs from previous reports using Clcn1, highlighting the effect of differences in splicing patterns between mice and humans.

The Drosophilatype II neuroblast lineages present an attractive model to investigate the neurogenesis and differentiation process as they adapt to a process similar to that in the human outer subventricular zone. We perform targeted single-cell mRNA sequencing in third instar larval brains to study this process of the type II NB lineage. Combining prior knowledge, in silicoanalyses, and in situvalidation, our multi-informatic investigation describes the molecular landscape from a single developmental snapshot. 17 markers are identified to differentiate distinct maturation stages. 30 markers are identified to specify the stem cell origin and/or cell division numbers of INPs, and at least 12 neuronal subtypes are identified. To foster future discoveries, we provide annotated tables of pairwise gene-gene correlation in single cells and MiCV, a web tool for interactively analyzing scRNA-seq datasets. Taken together, these resources advance our understanding of the neural differentiation process at the molecular level.

Earth‐abundant transition metal oxides are considered one of the most promising oxygen evolution reaction (OER) catalysts. However, their intrinsically low electrical conductivity inhibits the fast kinetics for OER. To overcome this drawback, hollow carbon@NiCo2O4core–shell microspheres (C@NiCo2O4HSs) are synthesized with enhanced electrocatalytic activity and stability toward OER. The prepared C@NiCo2O4/Ni foam delivers a current density of 10 mA cm−2at a small overpotential of 268 mV and exhibits a low Tafel slope of 54 mV dec−1. The enhanced OER performance is attributed to the enlarged specific surface area induced by the combination effect between the 1D nanosheet structure and the 3D hollow microsphere structure, and the improved electrical conductivity is ascribed to the carbon core support. Hollow C@NiCo2O4core–shell microspheres are synthesized with enhanced electrocatalytic activity and stability toward the oxygen evolution reaction. The prepared C@NiCo2O4/Ni foam delivers a current density of 10 mA cm−2at a small overpotential of 268 mV and exhibits a low Tafel slope of 54 mV dec−1.