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Objective Bench test is a primary technical means for studying the performance of high-speed EMU (electric multiple units) axle box bearings. Accurately simulating the practical operational load conditions of axle box bearings is essential for obtaining authentic and reliable performance data. A test bench for axle box bearings is reasonably designed to simulate the high-speed, heavy-load operational conditions. Control strategies for radial and axial loading mechanisms are developed to meet the requirements for control precision and response speed of the loading system. Method A dynamic loading system with electro-hydraulic servo is designed for the high-speed EMU axle box bearing reliability test bench. The structural composition and working principles of the axial and radial loading systems within this setup are introduced and a fuzzy-PID (proportional-integral-derivative) control algorithm is proposed. The axle box bearing reliability analysis test bench is constructed to conduct loading performance tests and axle box bearing reliability testing, thereby validating the rationality of the dynamic loading system. Result & Conclusion Test results indicate that the designed electro-hydraulic servo dynamic loading system meets the loading requirements for axle box bearing reliability test. The axial loading response time is 0.276 s, the axial loading steady-state error is 0.339 kN, and the radial loading steady-state error is 1.742 kN, all of which satisfy requirements specified in the EN 12082:2017 standards.

Granulomatous polyangiitis (GPA) is a rare systemic autoimmune vasculitis disease that is highly correlated with anti-neutrophil cytoplasmic antibodies (ANCAs). It was formerly called as “Wegener’s granulomatosis.” The clinical manifestations are diverse, mainly involving the upper respiratory tract, lungs, and kidneys, and this disease can involve the brain parenchyma as an isolated solid mass. Only one case has been reported thus far. To provide further information on this rare case, we report a case of GPA involving the fourth ventricle and review the relevant literature. A 32-year-old Chinese female developed fever, cough, and shortness of breath for 20 days. An 80 mm × 80 mm skin ulcer was seen on the right lower limb. CT showed multiple large patches of increased density in both lungs. The patient’s serological ANCA was positive. Later, the patient developed dizziness and headache. Magnetic resonance imaging of the head showed a mass of approximately 21 mm × 24 mm in the fourth ventricle. The patient had a craniotomy for mass resection, and macroscopically, the mass was gray–red and measured 25 mm × 20 mm × 20 mm, was soft, had local hemorrhage and necrosis, and had no capsule. The main microscopic features included necrotizing granulomatous vasculitis, the patient’s immunohistochemistry was positive for CD68 and negative for glial fibrillary acidic protein, and the acid-fast staining and hexaamine silver staining were negative. Combined with the clinical history, serology, and imaging, the pathological diagnosis was GPA in the fourth ventricle. The patient was switched to rituximab combined with steroid therapy because she did not tolerate cyclophosphamide. After 5 months of follow-up, the patient’s lung lesions and skin ulcers had completely improved, but the brain lesions had further progressed. When a patient has multiple system diseases, abnormal clinical manifestations, and positive serological ANCAs, a diagnosis of GPA should be carefully considered, and biopsies of easy-to-access sites should be performed. If the patient’s histopathological manifestations include vasculitis, granuloma, and necrosis, a diagnosis of GPA is more likely. If a patient subsequently develops an intraventricular mass, the clinicians should consider a diagnosis of GPA, which can rarely involve the cerebral ventricle to avoid an unnecessary biopsy or surgical treatment of intracranial lesions. When a patient is intolerant to the traditional treatment drug cyclophosphamide and needs to be switched to rituximab, the treatment effect of intracerebral lesions is not ideal; therefore, the treatment of lesions involving GPA in the ventricle is worthy of further exploration.

Gastric carcinoma is a frequent malignant tumor worldwide. NM23 plays an important role in pathological processes, including in the occurrence and development of tumors. The purpose of this study is to examine the effect of NM23 transfection of human gastric carcinoma cells (BGC-823) on growth and metastases of BGC-823 abdominal cancer xenografts in nude mice. BGC-823 cells were transfected with an adenovirus vector for NM23 (NM23-OE), transfected with an empty vector (NC), or were not transfected (Ctrl). Eighteen female BALB/c-nu mice were randomly divided into three groups (six per group) according to the type of BGC-823 cells administered by intraperitoneal injection. After 2 weeks, necropsies of mice were performed, abdominal circumferences were measured, and abdominal cavities were searched by ultrasound. In order to observe the xenografts in nude mice, there were gross macroscopic observations and microscopic observations. In addition, immunohistochemical analysis and western blot of NM23 were also performed. Green fluorescence in the NM23-OE and NC cells indicated successful transfection. The multiplicity of infection is 80%. A comparison of the three groups of mice indicated the NM23-OE group had positive conditions (abdominal circumferences: 81.83 ± 2.40 mm), but the other groups had negative conditions and enlarged abdomens (NC: 90.83 ± 2.32 mm; Ctrl: 92.67 ± 2.07 mm). Ultrasound observations confirmed large tumors in the NC and Ctrl groups, but did not find in the NM23-OE group. There were no obvious ascites in the NM23-OE group, but the cytological examination of ascites exfoliation in NC and Ctrl groups indicated that there were large and deep-stained gastric carcinoma cells. Tumor expression of NM23 was greater in the NM23-OE group than in the NC and Ctrl groups (both p < 0.05). In conclusion, transfection of BCG-823 cells with NM23 rather than an empty vector (NC) or no vector (Ctrl) led to reduced growth and metastases of abdominal cancer xenografts in nude mice.

Abstract Background Cyrtomium fortumei (J.) Smith is an important Chinese herbal medicine because of its biological functions. However, systematic and comprehensive studies on the phytochemicals from Cyrtomium fortumei (J.) Smith and their bioactivity are limited. Results Using the bioassay-guided technique, the ethyl acetate and n-BuOH extracts of the rhizomes of Cyrtomium fortumei (J.) Smith were shown to exhibit good antitumor activities, consequently leading to the isolation of 23 compounds. All compounds were isolated from the plant for the first time. The inhibitory activities of these compounds were investigated on tumor cells MGC-803, PC3, and A375 in vitro by MTT (thiazolyl blue tetrazolium bromide) assay, and the results showed that pimpinellin (3) had potent cytotoxic activities against the three cell lines, with the IC50 values of 14.4 ± 0.3 μM, 20.4 ± 0.5 μM, and 29.2 ± 0.6 μM, respectively. The mechanism of the antitumor action indicated that pimpinellin inhibited the growth of MGC-803 cells via the induction of tumor cell apoptosis, with apoptosis ratio of 27.44% after 72 h of treatment at 20 μM. Conclusions This study suggests that most of the compounds from the roots of Cyrtomium fortumei (J.) Smith could inhibit the growth of human carcinoma cells. Moreover, pimpinellin inhibited the growth of tumor cells via the induction of tumor cell apoptosis.

Abstract Background Tumor, is one of the major reason for human death, due to its widespread occurrence. Betulinic acid derivatives have attracted considerable attention as cancer chemopreventive agents and also as cancer therapeutics. Many of its derivatives inhibit the growth of human cancer cell lines by triggering apoptosis. With this background, we planned to synthesize a series of betulinic acid derivatives to assess their antiproliferation efficacy on human cancer cell lines. Results A series of novel betulinic acid derivatives were designed and synthesized as highlighted by the preliminary antitumor evaluation against MGC-803, PC3, A375, Bcap-37 and A431 human cancer cell lines in vitro. The pharmacological results showed that some of the compounds displayed moderate to high levels of antitumor activities with most of new exhibiting higher inhibitory activities compared to BA. The IC50 values of compound 3c on the five cancer cell lines were 2.3, 4.6, 3.3, 3.6, and 4.3 μM, respectively. Subsequent fluorescence staining and flow cytometry analysis (FCM) indicated that compound 3c could induce apoptosis in MGC-803 and PC3 cell lines, and the apoptosis ratios reached the peak (37.38% and 33.74%) after 36 h of treatment at 10 μM. Conclusions This study suggests that most of betulinic acid derivatives could inhibit the growth of human cancer cell lines. Furthermore, compound 3c could induce apoptosis of cancer cells.

As the sole producers of insulin under physiological conditions, the normal functioning of pancreatic β cells is crucial for maintaining glucose homeostasis in the body. Due to the high oxygen and energy demands required for insulin secretion, hypoxia has been shown to play a critical role in pancreatic β-cell dysfunction. Lipid metabolism abnormalities, a common metabolic feature in type 2 diabetic patients, are often accompanied by tissue hypoxia caused by metabolic overload and lead to increased free fatty acid (FFA) levels. However, the specific mechanisms underlying FFA-induced β-cell dysfunction remain unclear. Nicotinamide mononucleotide (NMN), a naturally occurring bioactive nucleotide, has garnered significant attention in recent years for its effectiveness in replenishing NAD+ and alleviating various diseases. Nevertheless, studies exploring the mechanisms through which NMN influences β-cell dysfunction remain scarce. In this study, we established an in vitro β-cell dysfunction model by treating INS-1 cells with palmitate (PA), including control, PA-treated, and PA combined with NMN or activator/inhibitor groups. Compared to the control group, cells treated with PA alone showed significantly reduced insulin secretion capacity and decreased expression of proteins related to the NAD+/AMPK/SIRT1/HIF-1α pathway. In contrast, NMN supplementation significantly restored the expression of pathway-related proteins by activating NAD+ and effectively improved insulin secretion. Results obtained using HIF-1α and AMPK inhibitors/activators further supported these findings. In conclusion, our study demonstrates that NMN reversed the PA-induced downregulation of the NAD+/AMPK/SIRT1/HIF-1α pathway, thereby alleviating β-cell dysfunction. Our study investigated the mechanisms underlying PA-induced β-cell dysfunction, examined how NMN mitigates this dysfunction and offered new insights into the therapeutic potential of NMN for treating β-cell dysfunction and T2DM. [ABSTRACT FROM AUTHOR]

Neutrophil extracellular traps (NETs) are three-dimensional reticular structures that release chromatin and cellular contents extracellularly upon neutrophil activation. As a novel effector mechanism of neutrophils, NETs possess the capacity to amplify localized inflammation and have been demonstrated to contribute to the exacerbation of various inflammatory diseases, including cardiovascular diseases and tumors. It is suggested that lysophosphatidylcholine (LPC), as the primary active component of oxidized low-density lipoprotein, represents a significant risk factor for various inflammatory diseases, such as cardiovascular diseases and neurodegenerative diseases. However, the specific mechanism of NETs formation induced by LPC remains unclear. Quercetin has garnered considerable attention due to its anti-inflammatory properties, serving as a prevalent flavonoid in daily diet. However, little is currently known about the underlying mechanisms by which quercetin inhibits NETs formation and alleviates associated diseases. In our study, we utilized LPC-treated primary rat neutrophils to establish an in vitro model of NETs formation, which was subsequently subjected to treatment with a combination of quercetin or relevant inhibitors/activators. Compared to the control group, the markers of NETs and the expression of P2X7R/P38MAPK/NOX2 pathway-associated proteins were significantly increased in cells treated with LPC alone. Quercetin intervention decreased the LPC-induced upregulation of the P2X7R/P38MAPK/NOX2 pathway and effectively reduced the expression of NETs markers. The results obtained using a P2X7R antagonist/activator and P38MAPK inhibitor/activator support these findings. In summary, quercetin reversed the upregulation of the LPC-induced P2X7R/P38MAPK/NOX2 pathway, further mitigating NETs formation. Our study investigated the potential mechanism of LPC-induced NETs formation, elucidated the inhibitory effect of quercetin on NETs formation, and offered new insights into the anti-inflammatory properties of quercetin. [ABSTRACT FROM AUTHOR]