Synthesis and biological evaluation of pseudolaric acid B derivatives as potential immunosuppressive agents.

Pseudolaric acid B (PB) derivatives with immunosuppressive activity were found by our group. In order to find potential immunosuppressive agents with high efficacy and low toxicity, a series of novel PB derivatives were synthesized and evaluated on their immunosuppressive activities. Most of the synthesized compounds were tested in vitro on murine T and B proliferation. In particular, compound 11 exhibited excellent inhibitory activity toward murine T cells (up to 19-fold enhancement compared to that of mycophenolatemofetil) and little cytotoxicity toward normal murine spleen cells. These experimental data demonstrated that some of these PB derivatives have great potential for future immunosuppressive studies.

Bibliometric and visualized analysis on hip fracture surgery and venous thromboembolism.

Background: Hip fractures primarily occur in older people and represent a significant public health issue due to their high incidence and mortality rate. The concurrent occurrence of venous thromboembolism (VTE) during the perioperative period exacerbates the threat to patient health. Methods: We retrieved all articles related to hip fracture surgery and venous VTE from the Web of Science core collection database from 2000 to 2023. For bibliometric analysis, we extracted relevant information, including year of publication, country, institution, journal, impact factor, title, author, category, reference, keywords, number of citations, average number of citations, and H-index. Results: A total of 1079 articles were retrieved, with 67 countries, 341 institutions, and 256 journals participating in research on hip fracture surgery and venous thromboembolism. The overall research showed an increasing trend. The United States, Harvard University, Injury-International Journal of The Care of The Injured, and Lassen MR are the leading country, institution, journal, and author respectively, in terms of publication. Research directions in this field mainly include the impact of preoperative anticoagulation on fracture surgery, intraoperative blood protection strategies, and postoperative prevention and treatment of VTE. Hotspots and trends in research include the relationship between direct oral anticoagulants and surgical timing, perioperative blood protection, intertrochanteric fractures, and geriatric traumatic fractures. Conclusions: This study constructed the knowledge structure of hip fracture surgery and VTE and identified research hotspots and trends. Future research should focus on developing a prediction system for VTE in hip fracture surgery to guide individualized prevention and treatment.

Adipogenic and osteogenic effects of OBS and synergistic action with PFOS via PPARγ-RXRα heterodimers.

Sodium p-perfluorous nonenoxybenzenesulfonate (OBS) is a novel alternative to perfluorooctane sulfonate (PFOS), with environmental health risks largely unknown. The present study aims to unravel the adipogenesis effects and underlying molecular initiating events of OBS, which are crucial for understanding and predicting its adverse outcome. In undifferentiated human mesenchymal stem cells (hMSCs), exposure to 1-100 nM of OBS for 7 days stimulated reactive oxygen species production. In the subsequent multipotent differentiation, hMSCs favored adipogenesis and repressed osteogenesis. The point of departure (PoD) for cellular responses of OBS was 38.85 nM, higher than PFOS (0.39 nM). Notably, OBS/PFOS co-exposure inhibited osteogenesis and synergistically promoted adipogenesis. Consistently, the expression of adipogenic marker genes was up-regulated, while that of osteogenic marker genes was down-regulated. The decreased adiponectin and elevated tumor necrosis factor α (TNFα) secretion were observed in differentiated cells exposed to the mixture of OBS and PFOS. The co-treatment of a peroxisome proliferator-activated receptor γ (PPARγ) antagonist alleviated the adipogenic effects of PFOS and its combination with OBS. Moreover, OBS/PFOS co-exposure induced peroxisome PPARγ activation in reporter gene assays, and increased formation of PPARγ - retinoid X receptor α (RXRα) heterodimers measured by co-immunoprecipitation assays. Molecular docking showed interaction energy of OBS (-20.7 kcal/mol) with intact PPARγ-RXRα complex was lower than that of PFOS (-25.9 kcal/mol). Overall, single OBS exhibited lower potency in inducing adipogenesis but is comparable to PFOS in repressing osteogenesis, whereas OBS/PFOS co-exposure increases interaction with PPARγ-RXRα heterodimers, resulting in the synergistic activation of PPARγ, ultimately enhancing adipogenesis at the expense of osteogenic differentiation. The results indicate the potential health risks of increased obesity and decreased bone density caused by OBS and its co-exposure with PFOS, as well as other perfluorinated alkylated substances mixtures.

Automatic identification method of bridge structure damage area based on digital image.

It is of great scientific and practical value to use effective technical means to monitor and warn the structural damage of bridges in real time and for a long time. Traditional image recognition network models are often limited by the lack of on-site images. In order to solve the problem of automatic recognition and parameter acquisition in digital images of bridge structures in the absence of data information, this paper proposes an automatic identification method for bridge structure damage areas based on digital images, which effectively achieves contour carving and quantitative characterization of bridge structure damage areas. Firstly, the digital image features of the bridge structure damage area are defined. By making full use of the feature that the pixel value of the damaged area is obviously different from that of the surrounding image, an image pre-processing method of the structure damaged area that can effectively improve the quality of the field shot image is proposed. Then, an improved Ostu method is proposed to organically fuse the global and local threshold features of the image to achieve the damaged area contour carving of the bridge structure surface image. The scale of damage area, the proportion of damage area and the calculation rule of damage area orientation are constructed. The key inspection and characteristic parameter diagnosis of bridge structure damage area are realized. Finally, test and analysis are carried out in combination with an actual project case. The results show that the method proposed in this paper is feasible and stable, which can improve the damage area measurement accuracy of the current bridge structure. The method can provide more data support for the detection and maintenance of the bridge structure.

Efficacy and Safety of a Subanesthetic Dose of Esketamine Combined with Propofol in Patients with Obesity Undergoing Painless Gastroscopy: A Prospective, Double-Blind, Randomized Controlled Trial.

Purpose: Patients with obesity are more susceptible to hypoxemia. Anesthetic management for patients with obesity undergoing painless gastroscopy presents a severe challenge for anesthesiologists. Esketamine is a NMDA antagonist that has been proven to be beneficial for ameliorating respiratory depression owing to its sympathomimetic effect; however, there are no relevant reports on its use in patients with obesity. We designed a randomized controlled trial to evaluate whether esketamine can be the ideal adjuvant to propofol sedation in patients with obesity undergoing painless gastroscopy. Patients and Methods: A total of 104 patients with obesity undergoing painless gastroscopy were randomly divided into group C (propofol+saline) and group S (propofol+esketamine 0.25 mg/kg). Anesthesia was induced by 2 mg/kg propofol with saline or esketamine. The consumption of propofol, hemodynamic parameters, duration of procedure, induction time, postoperative awakening time, and orientation recovery time were recorded. Adverse events and satisfaction scores were also recorded. Results: Propofol consumption was 274.4±22.6 mg and 201.3±16.6 mg in groups C and S, respectively. The induction time of groups C and S were 25.4±2.3 s and 17.8±1.9 s, respectively. The postoperative awakening times of groups C and S were 6.2±1.1 min and 4.8±1.3 min, respectively. Hemodynamic parameters were more stable in group S than in group C. The incidence of adverse events such as injection pain, hypoxemia, hypotension, bradycardia, choking, and body movement were significantly lower in group S. The satisfaction scores of the endoscopist and anesthesiologist were (4.58±0.49 vs 3.71±0.83) and (4.75±0.44 vs 3.33±0.92), respectively. Conclusion: The combination of propofol and esketamine (0.25 mg/kg) improves the safety and reduces the incidence of adverse events in patients with obesity during painless gastroscopy. Thus, this method is worthy of clinical application. Clinical Trials Registration: ChiCTR 2200062547.

Pentraxin 3 inhibits fibroblast growth factor 2 induced osteoclastogenesis in rheumatoid arthritis.

BACKGROUND: Synovial fibroblasts (SFs) act as key effector cells mediating synovial inflammation and joint destruction in rheumatoid arthritis (RA). Fibroblast growth factor 2 (FGF2) and its receptors (FGFRs) play important roles in RASF-mediated osteoclastogenesis. Pentraxin 3 (PTX3) is a soluble pattern recognition receptor with nonredundant roles in inflammation and innate immunity. PTX3 is produced by various cell types, including SFs and is highly expressed in RA. However, the role of PTX3 in FGF2-induced osteoclastogenesis in RA and the underlying mechanism have been poorly elucidated. METHODS: We first determined the expression of FGF2 and RANKL in synovial tissue and synovial fluid of RA patients. We then examined the effect of PTX3 on RASF osteoclastogenesis induced by endogenous and exogenous FGF2 in isolated RASF cells treated with FGF2 and/or recombinant PTX3 (rPTX3). Thirdly, we analyzed the effect of PTX3 on FGF2 binding to FGFR-1 and HSPG receptors on RASFs. Lastly, we evaluated joint morphology after injection of rPTX3 into collagen-induced arthritis (CIA) mice. RESULTS: FGF2 was confirmed to be highly expressed in both synovial tissue and synovial fluid of RA patients. FGF2 promoted cell proliferation and increased the expressions of RANKL and ICAM-1 and RANKL/OPG to induce osteoclastogenesis in RASF, while anti-FGF2 neutralized this effect. PTX3 significantly inhibited FGF2-induced RASF cell growth and osteoclastogenesis by preventing the interaction of 125I-FGF2 and FGFRs on the same cells. In addition, administration of rPTX3 significantly ameliorated cartilage and bone destruction in mice with CIA. CONCLUSIONS: PTX3 exhibited an inhibitory effect on the autocrine and paracrine stimulation of FGF2 on SFs, and ameliorated bone destruction in CIA mice. PTX3 may be implicated in bone destruction in RA, which may provide theoretical evidence and potential therapeutic targets for RA treatment.

Oligomeric proanthocyanidins inhibit apoptosis of chondrocytes induced by interleukin-1ß.

Oligomeric proanthocyanidin (OPC) is a water-soluble plant polyphenolic compound known for its cytoprotective effects in various tissue types. However, its effect on chondrocytes has not been well characterized. The present study aimed to investigate the effect of OPC on interleukin­1ß (IL­1ß)­induced apoptosis in chondrocytes, and to determine the mechanisms underlying the protective effects of OPC. Knee articular chondrocytes obtained from 6­week­old SPF Kunming mice were cultured and serially passaged. First­generation chondrocytes were selected for subsequent experiments following toluidine blue staining. Subsequent to IL­1ß and OPC administration, an MTT assay was performed to examine the viability rate of chondrocytes, and the optimal drug concentration was determined. The fluorescence dye 2',7'-dichlorofluorescein diacetate was used to determine the intracellular content of reactive oxygen species (ROS). Mitochondrial membrane potential (MMP) was measured using a 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolylcarbocyanine iodide (JC­1) assay. The apoptosis rate of chondrocytes was assessed using an Annexin V­FITC/PI assay and ultrastructural changes were observed under an electron microscope. The results demonstrated that OPC increased the survival rate of chondrocytes against IL­1ß­induced apoptosis. The most significant protective effect of OPC was observed at the concentration of 0.050 mg/ml. OPC reversed the increased ROS content and MMP levels, and inhibited IL­1ß­induced apoptosis in chondrocytes. In addition, OPC was revealed to protect the ultrastructural integrity of chondrocytes. Taken together, the results of the present study suggest that OPC protects chondrocytes against IL­1ß­induced damage by decreasing ROS content and MMP levels.

Pseudolaric acid B attenuates atopic dermatitis-like skin lesions by inhibiting interleukin-17-induced inflammation.

Pseudolaric acid B (PB), isolated from the extract of the root bark of Pseudolarix kaempferi Gordon, has been used as a traditional remedy for the treatment of skin diseases. However, the information of PB on atopic dermatitis (AD) remains largely unknown. In the present study, oral administration with PB improved the severity scores of AD-like skin lesions dose-dependently in NC/Nga mice through reducing serum IgE, pro-inflammatory cytokines, and the infiltration of inflammatory cells. In addition, PB significantly attenuated the levels of IL-17 and IL-22, and the proportion of Th17 cells in NC/Nga mice, as well as decreased IL-17-induced inflammation in RAW264.7 cells. Moreover, PB inhibited the phosphorylation of IκBα and miR-155 expression both in NC/Nga mice and in IL-17-stimulated RAW264.7 cells, which could be reversed by GW9662, a specific antagonist for PPARγ. The incorporation of GW9662 reversed the inhibitory effect of PB on the RORγ-mediated activation of the Il17 promoter. Transfection with PPARγ luciferase reporter gene further demonstrated the enhancement of PB on PPARγ transactivation. These findings indicate that PB could ameliorate AD-like skin lesions by inhibiting IL-17-induced inflammation in a PPARγ-dependent manner, which would provide experimental evidence of PB for the therapeutic potential on AD and other inflammatory skin diseases.

A novel Pseudolaric acid B derivative, Hexahydropseudolaric acid B, exterts an immunomodulatory effect in vitro/in vivo evaluation.

Identification of immunosuppressants from natural sources has a proven track record in immune mediated disorders. Pseudolaric acid B is a diterpenoid isolated from the roots of Pseudolarix amabilis, possessing potent immunomodulatory effect. However, the cytotoxicity limits its future clinical application. The purpose of this study was to investigate the immunosuppressive activity of Hexahydropseudolaric acid B, a Pseudolaric acid B derivative, on T cell-mediated immune response both in vitro and in vivo, and investigated its immunomodulatory effect to develop a more ascendant immunosuppressive agent. The results showed that Hexahydropseudolaric acid B could exert more preferable immunosuppressive activity and lower cytotoxicity than Pseudolaric acid B. Hexahydropseudolaric acid B significantly inhibited T cell proliferation activated by mitogen and alloantigen without obvious cytotoxicity in vitro. Furthermore, Hexahydropseudolaric acid B could ameliorate ear swelling in a mouse model of 2,4-dinitrofluorobenzene-induced delayed-type hypersensitivity in vivo. Mechanistic study revealed that Hexahydropseudolaric acid B could enhance regulatory T cells via promoting Foxp3 expression and TGF-ß level, accompanied by attenuating Akt activation, blocking p38MAPK/MK2-HSP27 signal cascades, and up-regulating PPAR-γ expression. Taken together, these results suggest that Hexahydropseudolaric acid B exerts more preferable immunosuppressive activity than its precursor Pseudolaric acid B by affecting multiple targets, which support the need for continued efforts to characterize the efficacy of HPAB as a promising and safe candidate to treat immune-related diseases.