Locomotion Control of Cyborg Insects by Charge-Balanced Biphasic Electrical Stimulation

The integration of electronic stimulation devices with insects in the context of cyborg insect systems has great application potential, particularly in the fields of environmental monitoring, urban surveillance, and rescue missions. Despite considerable advantages compared to the current robot technology, including flexibility, durability, and low energy consumption, this integration faces certain challenges related to the potential risk of charge accumulation caused by prolonged and repetitive electrical stimulations. To address these challenges, this study proposes a universal system for remote signal output control using infrared signals. The proposed system integrates high-precision digital-to-analog converters capable of generating customized waveform electrical stimulation signals within defined ranges. This enhances the accuracy of locomotion control in cyborg insects while maintaining real-time control and dynamic parameter adjustment. The proposed system is verified by experiments. The experimental results show that the signals generated by the proposed system have a success rate of over 76.25% in controlling the turning locomotion of cyborg insects, which is higher than previously reported results. In addition, the charge-balanced characteristics of these signals can minimize muscle tissue damage, thus substantially enhancing control repeatability. This study provides a comprehensive solution for the remote control and monitoring of cyborg insects, whose flexibility and adaptability can meet various application and experimental requirements. The results presented in this study lay a robust foundation for further advancement of various technologies, particularly those related to cyborg insect locomotion control systems and wireless control mechanisms for cyborg insects

Controllable adhesive mechanisms via the internal fibers in soft footpads of honeybees

The dynamic adhesive systems in nature have served as inspirations for the development of intelligent adhesive surfaces. However, the mechanisms underlying the rapid controllable contact adhesion observed in biological systems have never been adequately explained. Here, the control principle for the unfolding adhesive footpads (alterable contact area) of honeybees is investigated. The footpads can passively unfold, even without neuro-muscular reflexes, in response to specific dragging activity (generating shear force) toward their bodies. This passive unfolding is attributed to the structural features of the soft footpads, which cooperate closely with shear force. Then, the hierarchical structures supported by numerous branching fibers were observed and analyzed. Experimental and theoretical findings demonstrated that shear force can decrease fibril angles with respect to the shear direction, which consequently induces the rotation of the interim contact area of the footpads and achieves their passive unfolding. Furthermore, the decrease in fibril angles can lead to an increase in the liquid pressure within the footpads, and subsequently enhance their unfolding. This study presents a novel approach for passively controlling the contact areas in adhesive systems, which can be applied to develop various bioinspired switchable adhesive surfaces

Yirui Capsules Alleviate Atherosclerosis by Improving the Lipid Profile and Reducing Inflammation in Apolipoprotein E-Deficient Mice

Atherosclerosis (AS) is the main cause of cardiovascular diseases. This study investigated Yirui (YR) capsules, whose ingredients are available in health food stores, against AS and the underlying mechanisms. Male apolipoprotein E-deficient mice fed a high-fat diet for 10 weeks developed severe aortic lesions, but YR significantly decreased the plaque area in the total aorta and aortic root. YR affected the serum lipid profile by significantly reducing total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and oxidative modification of LDL-C (Ox-LDL) levels. In addition, multi-cytokine analysis revealed that higher serum levels of interleukin-1 alpha (IL-1α), interleukin-1 beta (IL-1β), interleukin-3 (IL-3), interleukin-6 (IL-6), interleukin-27 (IL-27), tumor necrosis factor alpha, interferon gamma, and regulated on activation, normal T cell expressed and secreted (RANTES), which were induced by a high-fat diet, declined with YR treatment. These results suggest that YR reduces the atherosclerotic plaque burden, thereby alleviating AS by modulating the lipid profile and inhibiting inflammation

The effect of sequential perioperative intravenous tranexamic acid in reducing postoperative blood loss and hidden blood loss after posterior lumbar interbody fusion: a randomized controlled trial

BackgroundTranexamic acid (TXA) has previously been shown to be effective in reducing intraoperative blood loss (IBL) and transfusion requirements in spine surgery. A conventional TXA regimen is a simple preoperative or intraoperative administration. However, the hyperfibrinolysis caused by surgical trauma lasts at least 24 h, and a single dose of TXA cannot cover the whole process of hyperfibrinolysis. Moreover, its ability to control postoperative blood loss (PBL) may be insufficient. Therefore, this study aimed to explore the effects and safety of sequential perioperative intravenous TXA for reducing bleeding after posterior lumbar interbody fusion (PLIF).MethodsPatients requiring PLIF were randomly divided into two groups. All patients were intravenously injected with 1 g of TXA 15 min before skin resection. Every day after the surgery, 200 ml saline was intravenously injected for 1–3 days in Group A, while Group B received 1 g of TXA instead of saline. The total blood loss (TBL), IBL, PBL, HCT, Hb, blood transfusion volume, inflammation-related indicators, and complications were recorded.ResultsTBL, PBL, and hidden blood loss (HBL) in Group B were significantly lower than those in Group A (P < 0.05). The maximum decreases in HCT and Hb in Group B were also significantly lower than those in Group A (P < 0.05), and the drainage removal time (DRT) was sooner in Group B than in Group A (P = 0.003). On the 3rd and 5th days after surgery, the level of CRP in Group B was significantly lower than that in Group A (P < 0.05). Similarly, IL-6 levels were significantly lower in Group B for the first 5 days postoperatively (P < 0.001). Sex, operation time, level of decompression, length of incision, and change in HCT were significant predictors of both TBL and HBL. TBL was also significantly associated with BMI and preoperative fibrinogen, while postoperative TXA was a significant predictor of HBL only.ConclusionIntravenous injection of 1 g of TXA 15 min before skin resection combined with continuous intravenous injection of 1 g of TXA 1 to 3 days after PLIF can reduce postoperative bleeding and shorten the time to drainage tube removal. In addition, it can also inhibit the postoperative inflammatory response.Clinical trial registrationChiCTR2200056210

Comparative analysis of immune activation markers of CD8+ T cells in lymph nodes of different origins in SIV-infected Chinese rhesus macaques

Altered T-cell homeostasis, such as expansion of CD8+ T cells to the secondary lymphatic compartments has been suggested as a mechanism of HIV/SIV-pathogenesis. However, the role of immune activation of CD8+ T cells in the CD4/CD8 turnover and viral replication in these tissues is not completely understood. In the present study, we compared the expression of immune activation markers (CD69 and HLA-DR) on CD8+ T cells in the peripheral blood and lymph nodes (LNs) of SIV-infected/uninfected Chinese rhesus macaques. SIV-infected macaques had significantly higher percentages of CD8+CD69+ and CD8+HLA-DR+ T cells in all these anatomical compartments than uninfected macaques except for CD8+HLA-DR+ T cells in peripheral blood. LNs that located close to the gastrointestinal (GI) tract (colon, mesenteric and iliac LNs) of SIV-infected macaques had profoundly lower numbers of CD4+ T cells, but no significantly difference in expression of activation marker (CD8+CD69+ and CD8+HLA-DR+) as compared with the peripheral lymphatic tissues (axillary and inguinal LNs). The CD4/CD8 ratios were negatively correlated with the activation of CD8 T cells in the overall LNs, with further associations with CD8+HLA-DR+ in GI LNs while CD8+CD69+ in peripheral LNs. These observations demonstrate that the increase of CD8+ T cell activation is a contributing factor for the decline of CD4/CD8 ratios in GI system

Modulation of monocyte activity by hepatocellular MicroRNA delivery through HBsAg particles:Implications for pathobiology of chronic hepatitis B

Background and Aims: HBsAg serves as an important immune-modulatory factor in chronic hepatitis B. One aspect of such modulation may act through monocytes, which are the major Ag-presenting cells taking up HBsAg. There is evidence for the encapsulation of hepatocellular microRNAs (miRNAs) by HBsAg particles, while its pathobiological significance is unclear. Here, we characterized the miRNA profile in patients with chronic hepatitis B and probed their association with liver inflammation. Approaches and Results: We collected plasma from patients that are treatment-naive with chronic hepatitis B (n = 110) and quantified total/HBsAg-enveloped miRNAs by qRT-PCR and plasma cytokines by ELISA. The biological effects of HBsAg-delivered miRNAs in monocytes were evaluated using multiple approaches. The clinical significance of candidate miRNAs and cytokines was corroborated in patients with HBV-associated advanced liver diseases. The plasma miRNA profile showed 2 major clusters, one significantly associated with HBsAg titer and the other correlated with liver inflammation. Among HBsAg-carried miRNAs, miR-939 displayed the most significant correlation with IL-8. Mechanistically, miR-939 in subviral particles enters monocytes and significantly augments IL-8 production through the mitogen-activated protein kinase (MAPK) p38 signaling pathway. Finally, the findings that miR-939 positively correlated with IL-8 level and inflammation/fibrosis stage in the cohort of HBV-associated advanced liver diseases support its causative role in the progression of liver diseases. Conclusions: HBsAg particles carry hepatocellular miRNAs, including miR-939, which enter monocytes and alter their functional status, such as IL-8 secretion. Our findings demonstrate that the HBsAg-miR-939-IL-8 axis may play a crucial role in HBV-induced hepatic necro-inflammation and the progression of advanced liver diseases.</p

Quantitative mapping of the cellular small RNA landscape with AQRNA-seq

Current next-generation RNA-sequencing (RNA-seq) methods do not provide accurate quantification of small RNAs within a sample, due to sequence-dependent biases in capture, ligation and amplification during library preparation. We present a method, absolute quantification RNA-sequencing (AQRNA-seq), that minimizes biases and provides a direct, linear correlation between sequencing read count and copy number for all small RNAs in a sample. Library preparation and data processing were optimized and validated using a 963-member microRNA reference library, oligonucleotide standards of varying length, and RNA blots. Application of AQRNA-seq to a panel of human cancer cells revealed >800 detectable miRNAs that varied during cancer progression, while application to bacterial transfer RNA pools, with the challenges of secondary structure and abundant modifications, revealed 80-fold variation in tRNA isoacceptor levels, stress-induced site-specific tRNA fragmentation, quantitative modification maps, and evidence for stress-induced, tRNA-driven, codon-biased translation. AQRNA-seq thus provides a versatile means to quantitatively map the small RNA landscape in cells

Integrated Analysis of DNA Methylation and RNA Transcriptome during <i>In Vitro</i> Differentiation of Human Pluripotent Stem Cells into Retinal Pigment Epithelial Cells

<div><p>Using the paradigm of <i>in vitro</i> differentiation of hESCs/iPSCs into retinal pigment epithelial (RPE) cells, we have recently profiled mRNA and miRNA transcriptomes to define a set of RPE mRNA and miRNA signature genes implicated in directed RPE differentiation. In this study, in order to understand the role of DNA methylation in RPE differentiation, we profiled genome-scale DNA methylation patterns using the method of reduced representation bisulfite sequencing (RRBS). We found dynamic waves of <i>de novo</i> methylation and demethylation in four stages of RPE differentiation. Integrated analysis of DNA methylation and RPE transcriptomes revealed a reverse-correlation between levels of DNA methylation and expression of a subset of miRNA and mRNA genes that are important for RPE differentiation and function. Gene Ontology (GO) analysis suggested that genes undergoing dynamic methylation changes were related to RPE differentiation and maturation. We further compared methylation patterns among human ESC- and iPSC-derived RPE as well as primary fetal RPE (fRPE) cells, and discovered that specific DNA methylation pattern is useful to classify each of the three types of RPE cells. Our results demonstrate that DNA methylation may serve as biomarkers to characterize the cell differentiation process during the conversion of human pluripotent stem cells into functional RPE cells.</p></div