This study aimed to investigate the effects of CpG Oligodeoxynucleotide (CpG ODNs)-Coated Chitosan Nanoparticles (CNP) on the phenotype of murine macrophages and their pro-inflammatory cytokine profile in vitro. CNP-CpG ODNs loaded with FITC-scrambled siRNA were prepared using the ionotropic gelation method. Peritoneal macrophages were isolated and exposed to CNP-CpG ODNs. Treated macrophages were assessed for uptake capacity. Flow cytometry was used to evaluate the expression levels of MHC-II, CD40, and CD86 costimulatory molecules in treated macrophages. Furthermore, the secretion levels of proinflammatory cytokines (TNF-α and IL-6) and the release of nitric oxide (NO) were measured in the culture supernatant of treated macrophages using sandwich ELISA and the Griess reaction, respectively. These in vitro studies showed that CNP-CpG ODNs had no cytotoxic effect on macrophages and were efficiently taken up by them. Additionally, CNP-CpG ODNs significantly increased the production of TNF-α, IL-6, and NO in the culture supernatant compared to CNP alone. Moreover, CNP-CpG ODNs enhanced the expression of MHC-II, CD40, and CD86 costimulatory molecules on macrophages. These findings indicate that incorporating CpG ODNs into CNPs promotes macrophage maturation and a proinflammatory phenotype. Therefore, CNP-CpG ODNs may serve as an effective system for targeted gene delivery to macrophages, enhancing immune responses.

Endosomal Toll-like receptors (eTLRs) are essential for the sensing of non-self through RNA and DNA detection. Here, using spatiotemporal analysis of vesicular dynamics, super-resolution microscopy studies, and functional assays, we show that endomembrane defects associated with the deficiency of the small GTPase Rab27a cause delayed eTLR ligand recognition, defective early signaling, and impaired cytokine secretion. Rab27a-deficient neutrophils show retention of eTLRs in amphisomes and impaired ligand internalization. Extracellular signal-regulated kinase (ERK) signaling and β2-integrin upregulation, early responses to TLR7 and TLR9 ligands, are defective in Rab27a deficiency. CpG-stimulated Rab27a-deficient neutrophils present increased tumor necrosis factor alpha (TNF-α) secretion and decreased secretion of a selected group of mediators, including interleukin (IL)-10. In vivo, CpG-challenged Rab27a-null mice show decreased production of type I interferons (IFNs) and IFN-γ, and the IFN-α secretion defect is confirmed in Rab27a-null plasmacytoid dendritic cells. Our findings have significant implications for immunodeficiency, inflammation, and CpG adjuvant vaccination.

暂无摘要。

Fast forward locomotion is critical for animal hunting and escaping behaviors. However, how the underlying neural circuit is wired at synaptic resolution to decide locomotion direction and speed remains poorly understood. Here, we identified in the ventral nerve cord (VNC) a set of ascending cholinergic neurons (AcNs) to be command neurons capable of initiating fast forward peristaltic locomotion in Drosophila larvae. Targeted manipulations revealed that AcNs are necessary and sufficient for fast forward locomotion. AcNs can activate their postsynaptic partners, A01j and A02j; both are interneurons with locomotory rhythmicity. Activated A01j neurons form a posterior-anteriorly descendent gradient in output activity along the VNC to launch forward locomotion from the tail. Activated A02j neurons exhibit quicker intersegmental transmission in activity that enables fast propagation of motor waves. Our work revealed a global neural mechanism that coordinately controls the launch direction and propagation speed of Drosophila locomotion, furthering the understanding of the strategy for locomotion control.

Feeding in pond snails has long been a model system for central pattern generation and its modulation. The pattern is generated by a small set of neurons in the buccal ganglia, which innervate the buccal mass, esophagus, and salivary glands. In this exercise, students observe feeding behavior and then record and quantify rhythmic motor activity and its response to feeding stimulants and neuromodulators. In a standard three-hour class period, students do a dissection, record from several nerves, and perform experimental manipulations such as adding feeding stimulants, serotonin, or dopamine to the preparation. Depending on the course goals, data can be presented qualitatively or cyclic measurements and spike-rate analysis can be done. This exercise leads to discussion of neural circuitry and intrinsic properties that support pattern generation for rhythmic activities such as feeding, locomotion, and respiration.

The search for the molecular markers of osteoporosis (OP), based on the analysis of differential deoxyribonucleic acid (DNA) methylation in bone cells and peripheral blood cells, is promising for developments in the field of the early diagnosis and targeted therapy of the disease. The Runt-related transcription factor 2 (RUNX2) gene is one of the key genes of bone metabolism, which is of interest in the search for epigenetic signatures and aberrations associated with the risk of developing OP. Based on pyrosequencing, the analysis of the RUNX2 methylation profile from a pool of peripheral blood cells in men and women over 50 years of age of Russian ethnicity from the Volga-Ural region of Russia was carried out. The level of DNA methylation in three CpG sites of the RUNX2 gene was assessed and statistically significant hypomethylation was revealed in all three studied CpG sites in men (U = 746.5, p = 0.004; U = 784, p = 0.01; U = 788.5, p = 0.01, respectively) and in one CpG site in women (U = 537, p = 0.03) with primary OP compared with control. In the general sample, associations were preserved for the first CpG site (U = 2561, p = 0.0001766). The results were obtained for the first time and indicate the existence of potentially new epigenetic signatures of RUNX2 in individuals with OP.

This study presents the design, simulation, and prototype creation of a quadruped robot inspired by the Acinonyx jubatus (cheetah), specifically designed to replicate its distinctive walking, trotting, and galloping locomotion patterns. Following a detailed examination of the cheetah\'s skeletal muscle anatomy and biomechanics, a simplified model of the robot with 12 degrees of freedom was conducted. The mathematical transformation hierarchy model was established, and direct kinematics were simulated. A bio-inspired control approach was introduced, employing a Central Pattern Generator model based on Wilson-Cowan neural oscillators for each limb, interconnected by synaptic weights. This approach assisted in the simulation of oscillatory signals for relative phases corresponding to four distinct gaits in a system-level simulation platform. The design phase was conducted using CAD software (SolidWorks 2018), resulting in a 1:3-scale robot mirroring the cheetah\'s actual proportions. Movement simulations were performed in a virtual mechanics software environment, leading to the construction of a prototype measuring 35.5 cm in length, 21 cm in width, 27 cm in height (when standing), and weighing approximately 2.1 kg. The experimental validation of the prototype\'s limb angular positions and trajectories was achieved through the image processing of video-recorded movements, demonstrating a high correlation (0.9025 to 0.9560) in joint angular positions, except for the knee joint, where a correlation of 0.7071 was noted. This comprehensive approach from theoretical analysis to practical implementation showcases the potential of bio-inspired robotics in emulating complex biological locomotion.

BACKGROUND: Genetic and environmental factors are implicated in many developmental processes. Recent evidence, however, has suggested that epigenetic changes may also influence the onset of puberty or the susceptibility to a wide range of diseases later in life. The present study aims to investigate changes in genomic DNA methylation profiles associated with pubertal onset analyzing human peripheral blood leukocytes from three different groups of subjects: 19 girls with central precocious puberty (CPP), 14 healthy prepubertal girls matched by age and 13 healthy pubertal girls matched by pubertal stage. For this purpose, the comparisons were performed between pre- and pubertal controls to identify changes in normal pubertal transition and CPP versus pre- and pubertal controls.
RESULTS: Analysis of methylation changes associated with normal pubertal transition identified 1006 differentially methylated CpG sites, 86% of them were found to be hypermethylated in prepubertal controls. Some of these CpG sites reside in genes associated with the age of menarche or transcription factors involved in the process of pubertal development. Analysis of methylome profiles in CPP patients showed 65% and 55% hypomethylated CpG sites compared with prepubertal and pubertal controls, respectively. In addition, interestingly, our results revealed the presence of 43 differentially methylated genes coding for zinc finger (ZNF) proteins. Gene ontology and IPA analysis performed in the three groups studied revealed significant enrichment of them in some pathways related to neuronal communication (semaphorin and gustation pathways), estrogens action, some cancers (particularly breast and ovarian) or metabolism (particularly sirtuin).
CONCLUSIONS: The different methylation profiles of girls with normal and precocious puberty indicate that regulation of the pubertal process in humans is associated with specific epigenetic changes. Differentially methylated genes include ZNF genes that may play a role in developmental control. In addition, our data highlight changes in the methylation status of genes involved in signaling pathways that determine the migration and function of GnRH neurons and the onset of metabolic and neoplastic diseases that may be associated with CPP in later life.

We present a novel set of quantitative measures for \"likeness\" (error function) designed to alleviate the time-consuming and subjective nature of manually comparing biological recordings from electrophysiological experiments with the outcomes of their mathematical models. Our innovative \"blended\" system approach offers an objective, high-throughput, and computationally efficient method for comparing biological and mathematical models. This approach involves using voltage recordings of biological neurons to drive and train mathematical models, facilitating the derivation of the error function for further parameter optimization. Our calibration process incorporates measurements such as action potential (AP) frequency, voltage moving average, voltage envelopes, and the probability of post-synaptic channels. To assess the effectiveness of our method, we utilized the sea slug Melibe leonina swim central pattern generator (CPG) as our model circuit and conducted electrophysiological experiments with TTX to isolate CPG interneurons. During the comparison of biological recordings and mathematically simulated neurons, we performed a grid search of inhibitory and excitatory synapse conductance. Our findings indicate that a weighted sum of simple functions is essential for comprehensively capturing a neuron\'s rhythmic activity. Overall, our study suggests that our blended system approach holds promise for enabling objective and high-throughput comparisons between biological and mathematical models, offering significant potential for advancing research in neural circuitry and related fields.

Due to their advantages of good stability, adaptability, and flexibility, multi-legged robots are increasingly important in fields such as rescue, military, and healthcare. This study focuses on the millipede, a multi-segmented organism, and designs a novel multi-segment biomimetic robot based on an in-depth investigation of the millipede\'s biological characteristics and locomotion mechanisms. Key leg joints of millipede locomotion are targeted, and a mathematical model of the biomimetic robot\'s leg joint structure is established for kinematic analysis. Furthermore, a central pattern generator (CPG) control strategy is studied for multi-jointed biomimetic millipede robots. Inspired by the millipede\'s neural system, a simplified single-loop CPG network model is constructed, reducing the number of oscillators from 48 to 16. Experimental trials are conducted using a prototype to test walking in a wave-like gait, walking with a leg removed, and walking on complex terrain. The results demonstrate that under CPG waveform input conditions, the robot can walk stably, and the impact of a leg failure on overall locomotion is acceptable, with minimal speed loss observed when walking on complex terrain. The research on the structure and motion control algorithms of multi-jointed biomimetic robots lays a technical foundation, expanding their potential applications in exploring unknown environments, rescue missions, agriculture, and other fields.