Abstract
Aim
NIH3T3 cell line with expression of human receptor for advanced glycation end-products (hRAGE) transduced with lentivirus vectors was used to analyze affinity, biological activity, ...and/or molecular mechanisms of molecules targeting the hRAGE pathway.
Method
The DNA fragment coding for hRAGE gene was integrated into the genome of NIH3T3 cells using lentivirus transduction. Cells expressing hRAGE were selected with puromycin, and the level of hRAGE expression was analyzed by Western blot. To establish a stable cell line, colonies of hRAGE-expressing cells were generated, and the level of RAGE expression in each engineered cell line was analyzed within 20 generations. Flow cytometry assay was used to verify affinity of anti-hRAGE antibody binding to hRAGE on the surface of engineered cells. The engineered NIH3T3 cell line was applied to assess effects of anti-hRAGE blocking antibody on amyloid β-induced cells apoptosis by CCK-8 assay.
Results
The engineered NIH3T3 cell line (hRAGE-NIH3T3) could stably express human RAGE. Commercial anti-RAGE polyclonal antibody could recognize and bind to human RAGE on the surface of hRAGE-NIH3T3 but not original NIH3T3 cells. In addition, hRAGE-NIH3T3 was more sensitive to RAGE pathway-dependent stimulation. Our data show that the hRAGE-NIH3T3 cell line established is an excellent tool in the study of RAGE-targeting molecules based on the cellular level, biological function, and RAGE-mediated molecular mechanisms.
Abstract
Interleukin-1 receptor antagonist is an important acute-phase protein and an immune mediator, and its expression is associated with the development of hepatitis or acute liver failure. The ...aim of this study was to investigate whether recombinant human interleukin-1 receptor antagonist directly targets and improves cell survival in a carbon tetrachloride-induced hepatocyte injury model
in vitro
. A human hepatoma cell line and a mouse hepatocyte cell line were used to establish carbon tetrachloride-induced cell injury models
in vitro
, and cell viability, apoptosis, and reactive oxygen species level were determined to assess the degree of hepatocellular damage. Quantitative real-time polymerase chain reaction was used to analyze the level of interleukin-1β, interleukin-6, and tumor necrosis factor-α mRNA in cells; extracellular regulated protein kinases 1/2 phosphorylation in hepatocytes was analyzed using western blotting. Recombinant human interleukin-1 receptor antagonist could directly target hepatocytes, improve cell survival, and decrease carbon tetrachloride-induced cell apoptosis
in vitro
. In hepatocytes, recombinant human interleukin-1 receptor antagonist remarkably downregulated expression of interleukin-1β, interleukin-6, and tumor necrosis factor-α in hepatocytes exposed to carbon tetrachloride. It also decreased accumulation of reactive oxygen species and abrogated the suppression of extracellular regulated protein kinases 1/2 phosphorylation induced by carbon tetrachloride. However, stimulation of cells with an extracellular regulated protein kinases 1/2 inhibitor blocked the recombinant human interleukin-1 receptor antagonist-induced upregulation of extracellular regulated protein kinase1/2 activation and abrogated the improvement in hepatocyte survival following carbon tetrachloride treatment. Collectively, these findings provide new insights into the hepatocyte-protective mechanism of recombinant human interleukin-1 receptor antagonist.
Superb reliability and biocompatibility equip aggregation‐induced emission (AIE) dots with tremendous potential for fluorescence bioimaging. However, there is still a chronic lack of design ...instructions of excretable and bright AIE emitters. Here, a kind of PEGylated AIE (OTPA‐BBT) dots with strong absorption and extremely high second near‐infrared region (NIR‐II) PLQY of 13.6% is designed, and a long‐aliphatic‐chain design blueprint contributing to their excretion from an animal's body is proposed. Assisted by the OTPA‐BBT dots with bright fluorescence beyond 1100 nm and even 1500 nm (NIR‐IIb), large‐depth cerebral vasculature (beyond 600 µm) as well as real‐time blood flow are monitored through a thinned skull, and noninvasive NIR‐IIb imaging with rich high‐spatial‐frequency information gives a precise presentation of gastrointestinal tract in marmosets. Importantly, after intravenous or oral administration, the definite excretion of OTPA‐BBT dots from the body is demonstrated, which provides influential evidence of biosafety.
The long aliphatic chains of aggregation‐induced emission (AIE)‐gens are conducive to the excretion of AIE dots from an animal's body. The deep micro cerebrovasculature in marmosets is visualized through the thinned skull. Non‐invasive and high‐spatial‐frequency near‐infrared‐IIb imaging is utilized in non‐human primates. It is believed this work provides crucial ideas to advance the development of biosafe AIE dots and future nanomedicine.
Corrugated rolling is one of the metal forming processes using corrugated rolls to machine hard-to-deform metals, which leads to problems of high friction and severe wear. Lubricants are essential to ...reduce rolling forces, extend the life of corrugated rolls, and improve efficiency. In this work, a comparison of the surface quality of copper plates after corrugated rolling adopting different lubrication conditions (dry condition, O/W lubricant, TiO
2
water-based nanolubricants) was made to explore the tribological behavior and lubricant mechanism of water-based nanolubricant during the corrugated rolling of copper plates. The results show that the 3.0 wt.% water-based nanolubricant exhibits excellent lubrication performance, and the maximum rolling force is reduced by 21.49% compared with the dry condition. Additionally, the effect of reduction on the surface quality of corrugated rolled copper plates was explored. The surface roughness at the peak position of the copper plate increased gradually with increasing reduction, and the surface roughness at the trough position showed little change, which was mainly caused by the synergistic effect of the roughness transfer and the high-strain hardening at the trough position of the copper plate. Overall, an optimal concentration of 3.0 wt.% water-based nanolubricant exhibits the best properties in terms of reducing the rolling forces and improving the surface quality of the rolled copper plates during corrugated rolling processes.
During past decades, water-based and oil-in-water (O/W) based nanolubricants with nanoparticles (NPs) as additives have been developed to replace conventional oil-based lubricants for solving ...contamination problems during rolling processes. The formulations of nanolubricants for rolling need to be continuously improved to provide better lubrication performance. This article reviews the formulation, physicochemical properties, and lubrication mechanisms during rolling with water-based and O/W based nanolubricants, and the effects of nanolubricants on rolling force, surface roughness and oxide skin formation during rolling are discussed. This review aims to facilitate the fundamental understanding of nanolubrication and the development of rolling lubrication technology.
An Ir(iii)-catalyzed relay aryl C-H bond carbenoid insertion cascade of N-aryl-2-pyridinamines with diazo Meldrum's acid has been developed. This method provides an efficient approach to ...multifunctionalized 1,3-dihydroindol-2-ones with a broad range of functional group tolerance. Furthermore, this protocol could be applied for the concise synthesis of bioactive hematopoietic growth factor analogues.
Abstract
Temporal processing is crucial for auditory perception and cognition, especially for communication sounds. Previous studies have shown that the auditory cortex and the thalamus use temporal ...and rate representations to encode slowly and rapidly changing time-varying sounds. However, how the primate inferior colliculus (IC) encodes time-varying sounds at the millisecond scale remains unclear. In this study, we investigated the temporal processing by IC neurons in awake marmosets to Gaussian click trains with varying interclick intervals (2–100 ms). Strikingly, we found that 28% of IC neurons exhibited rate representation with nonsynchronized responses, which is in sharp contrast to the current view that the IC only uses a temporal representation to encode time-varying signals. Moreover, IC neurons with rate representation exhibited response properties distinct from those with temporal representation. We further demonstrated that reversible inactivation of the primary auditory cortex modulated 17% of the stimulus-synchronized responses and 21% of the nonsynchronized responses of IC neurons, revealing that cortico-colliculus projections play a role, but not a crucial one, in temporal processing in the IC. This study has significantly advanced our understanding of temporal processing in the IC of awake animals and provides new insights into temporal processing from the midbrain to the cortex.
Abstract
Cortical feedback has long been considered crucial for the modulation of sensory perception and recognition. However, previous studies have shown varying modulatory effects of the primary ...auditory cortex (A1) on the auditory response of subcortical neurons, which complicate interpretations regarding the function of A1 in sound perception and recognition. This has been further complicated by studies conducted under different brain states. In the current study, we used cryo-inactivation in A1 to examine the role of corticothalamic feedback on medial geniculate body (MGB) neurons in awake marmosets. The primary effects of A1 inactivation were a frequency-specific decrease in the auditory response of most MGB neurons coupled with an increased spontaneous firing rate, which together resulted in a decrease in the signal-to-noise ratio. In addition, we report for the first time that A1 robustly modulated the long-lasting sustained response of MGB neurons, which changed the frequency tuning after A1 inactivation, e.g. some neurons are sharper with corticofugal feedback and some get broader. Taken together, our results demonstrate that corticothalamic modulation in awake marmosets serves to enhance sensory processing in a manner similar to center-surround models proposed in visual and somatosensory systems, a finding which supports common principles of corticothalamic processing across sensory systems.
ABSTRACT
Human speech and animal vocalizations are important for social communication and animal survival. Neurons in the auditory pathway are responsive to a range of sounds, from elementary sound ...features to complex acoustic sounds. For social communication, responses to distinct patterns of vocalization are usually highly specific to an individual conspecific call, in some species. This includes the specificity of sound patterns and embedded biological information. We conducted single-unit recordings in the amygdala of awake marmosets and presented calls used in marmoset communication, calls of other species and calls from specific marmoset individuals. We found that some neurons (47/262) in the amygdala distinguished ‘Phee’ calls from vocalizations of other animals and other types of marmoset vocalizations. Interestingly, a subset of Phee-responsive neurons (22/47) also exhibited selectivity to one out of the three Phees from two different ‘caller’ marmosets. Our findings suggest that, while it has traditionally been considered the key structure in the limbic system, the amygdala also represents a critical stage of socially relevant auditory perceptual processing.
This study reveals a crucial role of the amygdala in processing the conspecific vocalization.
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