Thymocyte migration and emigration.

Hematopoietic precursors (HPCs) entering into the thymus undergo a sequential process leading to the generation of a variety of T cell subsets. This developmental odyssey unfolds in distinct stages within the thymic cortex and medulla, shaping the landscape of T cell receptor (TCR) expression and guiding thymocytes through positive and negative selection. Initially, early thymic progenitors (ETPs) take residence in the thymic cortex, where thymocytes begin to express their TCR and undergo positive selection. Subsequently, thymocytes transition to the thymic medulla, where they undergo negative selection. Both murine and human thymocyte development can be broadly classified into distinct stages based on the expression of CD4 and CD8 coreceptors, resulting in categorizations as double negative (DN), double positive (DP) or single positive (SP) cells. Thymocyte migration to the appropriate thymic microenvironment at the right differentiation stage is pivotal for the development and the proper functioning of T cells, which is critical for adaptive immune responses. The journey of lymphoid progenitor cells into the T cell developmental pathway hinges on an ongoing dialogue between the differentiating cell and the signals emanating from the thymus niche. Herein, we review the contribution of the key factors mentioned above for the localization, migration and emigration of thymocytes.

Qi-dan-dihuang decoction ameliorates renal fibrosis in diabetic rats via p38MAPK/AKT/mTOR signaling pathway.

CONTEXT: Qi-dan-dihuang decoction (QDD) has been used to treat diabetic kidney disease (DKD), but the underlying mechanisms are poorly understood. OBJECTIVE: This study reveals the mechanism by which QDD ameliorates DKD. MATERIALS AND METHODS: The compounds in QDD were identified by high-performance liquid chromatography and quadrupole-time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS). Key targets and signaling pathways were screened through bioinformatics. Nondiabetic Lepr db/m mice were used as control group, while Lepr db/db mice were divided into model group, dapagliflozin group, 1% QDD-low (QDD-L), and 2% QDD-high (QDD-H) group. After 12 weeks of administration, 24 h urinary protein, serum creatinine, and blood urea nitrogen levels were detected. Kidney tissues damage and fibrosis were evaluated by pathological staining. In addition, 30 mmol/L glucose-treated HK-2 and NRK-52E cells to induce DKD model. Cell activity and migration capacity as well as protein expression levels were evaluated. RESULTS: A total of 46 key target genes were identified. Functional enrichment analyses showed that key target genes were significantly enriched in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) signaling pathways. In addition, in vivo and in vitro experiments confirmed that QDD ameliorated renal fibrosis in diabetic mice by resolving inflammation and inhibiting the epithelial-mesenchymal transition (EMT) via the p38MAPK and AKT-mammalian target of rapamycin (mTOR) pathways. DISCUSSION AND CONCLUSION: QDD inhibits EMT and the inflammatory response through the p38MAPK and AKT/mTOR signaling pathways, thereby playing a protective role in renal fibrosis in DKD.

Identification of Circular RNAs in the Anterior Pituitary in Rats Treated with GnRH.

The pituitary gland, an important endocrine organ, can secrete a variety of reproductive hormones under the action of hypothalamus-secreted gonadotropin-releasing hormone (GnRH) and plays important roles in animal reproduction. Circular RNAs (circRNAs) are a class of RNA molecules with stable covalently closed circular structures. CircRNAs are equipped with miRNA response elements (MREs), which can regulate the expression of target genes by competitively binding miRNAs. However, whether the expression levels of circRNAs in the pituitary gland change under the action of GnRH and whether such changes can further affect the secretion of reproductive hormones are still unclear. In this study, we performed RNA sequencing (RNA-Seq) of GnRH-treated rats to identify differentially expressed circRNAs. The results revealed 1433 related circRNAs, 14 of which were differentially expressed. In addition, we randomly selected five differentially expressed circRNAs and tested their relative expression levels by RT-qPCR, the results of which were consistent with the RNA sequencing results. Finally, we predicted targeted relationships between the differentially expressed circRNAs and FSHb-LHb-associated miRNAs. In all, a total of 14 circRNAs were identified that may act on the secretion and regulation of reproductive hormones in GnRH-treated rats. Our expression profiles of circRNAs in the anterior pituitaries of rats treated with GnRH can provide insights into the roles of circRNAs in mammalian development and reproduction.

Influence of Lab Adapted Natural Diet and Microbiota on Life History and Metabolic Phenotype of Drosophila melanogaster.

Symbiotic microbiota can help its host to overcome nutritional challenges, which is consistent with a holobiont theory of evolution. Our project investigated the effects produced by the microbiota community, acquired from the environment and horizontal transfer, on metabolic traits related to obesity. The study applied a novel approach of raising Drosophila melanogaster, from ten wild-derived genetic lines on naturally fermented peaches, preserving genuine microbial conditions. Larvae raised on the natural and standard lab diets were significantly different in every tested phenotype. Frozen peach food provided nutritional conditions similar to the natural ones and preserved key microbial taxa necessary for survival and development. On the peach diet, the presence of parental microbiota increased the weight and development rate. Larvae raised on each tested diet formed microbial communities distinct from each other. The effect that individual microbial taxa produced on the host varied significantly with changing environmental and genetic conditions, occasionally to the degree of opposite correlations.

Synthesis of Active Graphene with Para-Ester on Cotton Fabrics for Antistatic Properties.

The excellent electrical properties of graphene provide a new functional finishing idea for fabricating conductive cotton fabrics with antistatic properties. This work develops a novel method for synthesizing active graphene to make cotton fabrics conductive and to have antistatic properties. The graphite was oxidized to graphene oxide (GO) by the Hummers method, and was further acid chlorinated and reacted with the para-ester to form the active graphene (JZGO). JZGO was then applied to cotton fabrics and was bonded to the fiber surface under alkaline conditions. Characterizations were done using FT-IR, XRD and Raman spectroscopy, which indicated that the para-ester group was successfully introduced onto JZGO, which also effectively improved the water dispersibility and reactivity of the JZGO. Furthermore, this study found that the antistatic properties of the fabric were increased by more than 50% when JZGO was 3% by weight under low-humidity conditions. The washing durability of the fabrics was also evaluated.

A Novel Fault Location Method for a Cross-Bonded HV Cable System Based on Sheath Current Monitoring.

In order to improve the practice in the operation and maintenance of high voltage (HV) cables, this paper proposes a fault location method based on the monitoring of cable sheath currents for use in cross-bonded HV cable systems. This method first analyzes the power⁻frequency component of the sheath current, which can be acquired at cable terminals and cable link boxes, using a Fast Fourier Transform (FFT). The cable segment where a fault occurs can be localized by the phase difference between the sheath currents at the two ends of the cable segment, because current would flow in the opposite direction towards the two ends of the cable segment with fault. Conversely, in other healthy cable segments of the same circuit, sheath currents would flow in the same direction. The exact fault position can then be located via electromagnetic time reversal (EMTR) analysis of the fault transients of the sheath current. The sheath currents have been simulated and analyzed by assuming a single-phase short-circuit fault to occur in every cable segment of a selected cross-bonded high voltage cable circuit. The sheath current monitoring system has been implemented in a 110 kV cable circuit in China. Results indicate that the proposed method is feasible and effective in location of HV cable short circuit faults.

Preparation of antibacterial silk fibroin membranes via tyrosinase-catalyzed coupling of ε-polylysine.

Silk fibroins have good biocompatibility and could be used to form a variety of regenerated functional biomaterials. In this study, enzymatic oxidization of silk fibroins with tyrosinase (TYR) was carried out, followed by coupling of ε-polylysine (ε-PLL) for improving antibacterial ability of the fibroin-based biomaterial. Trinitrobenzene sulfonic acid (TNBS) was selectively used to incubate with silk fibroins prior to TYR treatment, aiming at preventing the self-crosslinking of silk fibroins during enzymatic oxidation. The results indicated that tyrosine residues in silk fibroins could be converted to reactive dioxyphenylalanine and o-quinone residues TYR successively. TNBS pretreatment inhibited the self-crosslinks of silk fibroins and promoted the successive coupling of ε-PLL to fibroin proteins with high graft yield. The combined use of TNBS, TYR, and ε-PLL treatments endowed fibroin membrane with satisfactory antibacterial ability against Staphylococcus aureus, and the obtained durability was also acceptable. The changes in surface potential and amine acid composition for the fibroin membranes verified the favorable actions of the combined treatment. The present method could be potentially utilized for enzymatic functionalization of various fibroin-based biomaterials.