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Polymethyl methacrylate (PMMA) based biomaterials have been widely utilized in clinics. However, currently, PMMA catalyzed by benzoyl peroxide (BPO) exhibits disquieting disadvantages including an exothermic polymerization reaction and a lack of bioactivity. Here, we first designed three industrial-scale synthesis methods for high-purity butoxydibutylborane (BODBB), achieving purity levels greater than 95% (maximum: 97.6%) and ensuring excellent fire safety. By utilizing BODBB as a catalyst, the highest polymerization temperature of PMMA bone cement (PMMA–BODBB) reached only 36.05 °C, ensuring that no thermal damage occurred after implantation. Compared to PMMA catalyzed by BPO and partially oxidized tributylborane (TBBO, catalyst of Super Bond C&B), PMMA–BODBB exhibited superior cell adhesion, proliferation, and osteogenesis, attributed to the reduced release of free radicals and toxic monomer, and moderate bioactive boron release. After injection into a 5 mm defect in the rat cranial bone, PMMA–BODBB demonstrated the highest level of osteointegration. This work not only presents an industrial-scale synthesis of high-purity BODBB, but also offers an innovative PMMA biomaterial system with intrinsic biocompatibility and osseointegration, paving the way for the next generation of PMMA-based biomaterials with broader applications. [ABSTRACT FROM AUTHOR]

Background: This retrospective cohort study explores a practical approach to acquiring pathogenic microorganisms in patients with bone and joint infections. Methods: From Aug 2018 to Mar 2022, 68 consecutive patients (87 cultures) with bone and joint infection were recruited in this study. All cultures followed the Peking University First Hospital Procedure of Culturing Pathogenic microorganisms for bone and joint infection. Tissue samples were obtained through fluoroscopy-guided biopsy or open debridement. Tissue samples were divided into manual homogenization (MH), manual mixture (MM), and pathological examination. The baseline, antibiotic exposure, laboratory, surgical, and microbial data were reviewed. Independent sample T-test, Mann–Whitney U-test, and Chi-square test were used to detect the difference between patients who received different processing measures. Results: The average age was 55.8± 2.4 years old. Thirty-nine patients were male. The total positive culture rate of the manual homogenization group was 80.5% (70/87). Thirty-five patients had mixed infections with more than one microorganism cultured. Staphylococci accounted for 60.23% of all microorganisms. Staphylococcus aureus (18.2%) and Staphylococcus epidermidis (15.9%) were the two most common bacteria cultured in this study. Patients with positive culture in the manual mixture group had significantly higher WBC (p = 0.006), NE% (p = 0.024), ESR (p = 0.003), CRP (p = 0.020) and IL6 (0.050) compared to patients with negative culture. After tissue homogenization, only ESR is still statistically different. Patients without SIRS had a low positive culture rate (59.4%). Tissue homogenization could significantly increase the positive culture rate of patients without SIRS. Pre-culture antibiotic exposure was not an independent risk factor for culture results. Conclusion: Peking University First Hospital Procedure for Culturing Pathogenic microorganisms for Bone and Joint Infections was a practical approach for obtaining pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Objective To explore the possible molecular regulation mechanism of COPB2 on human osteosarcoma cells based on the bioinformatics analysis of ingenuity pathway analysis (IPA). Methods RT-qPCR was used to detect the expression levels of COPB2 in human osteosarcoma cell lines U-2OS, MG-63, HOS and Saos-2. U-2OS was used as the research object and divided into silence group (KD) and control group (NC). U-2OS cells were infected by green fluorescent protein-labeled lentivirus and the KD group contained COPB2 silenced sequence. Human gene expression profiling microarray was used to detect the difference in gene expression profile of U-2OS cells after COPB2 silencing. The detection information was input into the IPA software for bioinformatics analysis, including classical pathway analysis, upstream regulation analysis, disease function analysis, regulatory effect analysis and interaction network analysis. Results COPB2 had a high expressive abundance in four human osteosarcoma cell lines. There were significant differences in the expression of 1393 genes between KD group and NC group; 831 genes were up-regulated and 562 genes were down-regulated. After COPB2 knockdown, the inhibition of angiogenesis by TSP1 pathway and acute phase response pathway were significantly activated, while cyclins and cell cycle regulation pathway were significantly inhibited. COPB2 mainly affected neoplasia, invasion and anoikis of osteosarcoma cells. Conclusion COPB2 is highly expressed in human osteosarcoma cell lines, and might be involved in the development of osteosarcoma through cyclins and cell cycle regulation pathway. In addition, COPB2 is associated with neoplasia, invasion and anoikis of osteosarcoma cells.

Objective To evaluate the safety and efficacy of percutaneous vertebroplasty(PVP) in the treatment of spinal metastases with incomplete posterior wall. Methods We retrospectively analyzed 106 spinal metastases patients with incomplete posterior wall treated with PVP. Demographic and pre- and post-operative clinical characteristics were reviewed. Pain relief and functional activities recovery, systemic complications and the local leakage of the bone cement were evaluated before and after operation. Results All patients successfully underwent surgery, VAS score was 3.0(2.0-5.0) after operation and decreased for 5.0(3.0-7.0). Among 70 patients who received the assessment, 10 patients had a better Barthel Index(BI) and 46 patients were with the same activity of daily living. None had systemic complications during the injection of bone cement. Among the 160 vertebrae with incomplete vertebral posterior wall, 39(24.4%) vertebrae showed bone cement leakage and 7(4.4%) vertebrae were intraspinal leakage. None had bone cement leakage-related neurological symptoms after operation. Conclusion Percutaneous vertebroplasty is effective and safe in the treatment of spinal metastases with incomplete posterior wall.

Efficient deep-water offshore wind power installation platforms with a pressurized self-elevating mat are a new type of equipment used for installing offshore wind turbines. However, the unstable internal pressure of the pressurized self-elevating mat can cause serious harm to the platform. This paper studies the pneumatic control system of the self-elevating mat to improve the precision of its pressure control. According to the pneumatic control system structure of the self-elevating mat, the pneumatic model of the self-elevating mat is established, and a conventional PID controller and fuzzy PID controller are designed and established. It can be seen via Simulink simulation that the fuzzy PID controller has a smaller adjustment time and overshoot, but its anti-interference ability is relatively weak. The membership degree and fuzzy rules of the fuzzy PID controller are optimized using a neural network algorithm, and a fuzzy neural network PID controller based on BP neural network optimization is proposed. The simulation results show that the overshoot of the optimized controller is reduced by 9.71% and the stability time is reduced by 68.9% compared with the fuzzy PID. Finally, the experiment verifies that the fuzzy neural network PID controller has a faster response speed and smaller overshoot, which improves the pressure control accuracy and robustness of the self-elevating mat and provides a scientific basis for the engineering applications of the self-elevating mat. [ABSTRACT FROM AUTHOR]

Studies have shown that exosomes can mediate the chemoresistance of drug‐resistant cells by transmitting circular RNAs (circRNAs). However, the role of exosome‐derived hsa_circ_103801 (exosomal hsa_circ_103801) in osteosarcoma (OS) remains unclear. The level of hsa_circ_103801 was upregulated in the serum exosomes from patients with OS, and OS patients with high hsa_circRNA_103801 expression had a shorter survival time relative to patients with low hsa_circ_103801 expression. The expression of hsa_circ_103801 was upregulated in cisplatin‐resistant MG63 (MG63/CDDP) cells compared with that in MG63 cells. In addition, hsa_circ_103801 was highly enriched in exosomes derived from CDDP‐resistant OS cells and could be delivered to MG63 and U2OS cells through exosomes. Exosomes derived from CDDP‐resistant cells were shown to reduce the sensitivity of MG63 and U2OS cells to CDDP, inhibit apoptosis, and increase the expression of multidrug resistance‐associated protein 1 and P‐glycoprotein. Moreover, exosomal hsa_circ_103801 could strengthen the promotive effect of exosomes on the chemoresistance of MG63 and U2OS cells to CDDP. Hence, serum exosomal hsa_circ_103801 may serve as an effective prognostic biomarker for OS, and exosomal hsa_circ_103801 could be a potential target for overcoming OS chemoresistance. [ABSTRACT FROM AUTHOR]

1. Berberine (BBR), an isoquinoline alkaloid, has demonstrated multiple clinical pharmacological actions. As a substrate of multiple transporters in the liver, BBR is rarely excreted into the bile but can be found in the urine. The purpose of the present study was to investigate the role of multidrug and toxin extrusion protein 1 (MATE1) in the transport of BBR in the liver and kidney. 2. Using human MATE1 (hMATE1)-transfected HEK293 cells, BBR was shown to be a substrate of hMATE1 (Km = 4.28 ± 2.18 μM). In primary rat hepatocytes, pH-dependent uptake and efflux studies suggested that the transport of BBR was driven by the exchange of H+and involved Mate1. In rats, we found that pyrimethamine (PYR), an inhibitor of Mate1, increased hepatic and renal distribution of BBR and decreased systematic excretion of BBR. 3. These findings indicated that BBR is a substrate of MATE1 and that hepatic and renal Mate1 promote excretion of BBR into bile and urine, respectively. In conclusion, Mate1 plays a key role in the distribution and excretion of BBR, and we speculate that drug–drug interactions (DDIs) caused by MATE1 may occur between BBR and other co-administered drugs. [ABSTRACT FROM AUTHOR]