Beneficial Effects of Coculturing Synovial Derived Mesenchymal Stem Cells with Meniscus Fibrochondrocytes Are Mediated by Fibroblast Growth Factor 1: Increased Proliferation and Collagen Synthesis

Meniscus reconstruction is in great need for orthopedic surgeons. Meniscal fibrochondrocytes transplantation was proposed to regenerate functional meniscus, with limited donor supply. We hypothesized that coculture of synovial mesenchymal stem cells (SSC) with meniscal fibrochondrocytes (me-CH) can support matrix production of me-CH, thus reducing the number of me-CH needed for meniscus reconstruction. A pellet coculture system of human SSC and me-CH was used in this study. Enhanced glycosaminoglycans (GAG) in coculture pellets were demonstrated by Alcian blue staining and GAG quantification, when compared to monoculture. More collagen synthesis was shown in coculture pellets by hydroxyproline assay. Increased proliferation of me-CH was observed in coculture. Data from BrdU staining and ELISA demonstrated that conditioned medium of SSCs enhanced the proliferation and collagen synthesis of me-CH, and this effect was blocked by neutralizing antibody against fibroblast growth factor 1 (FGF1). Western blot showed that conditioned medium of SSCs can activate mitogen-activated protein kinase (MAPK) signaling pathways by increasing the phosphorylation of mitogen-activated regulated protein kinase 1/2 (MEK) and extracellular-signal-regulated kinases 1/2 (ERK). Overall, this study provided evidence that synovial MSCs can support proliferation and collagen synthesis of fibrochondrocytes, by secreting FGF1. Coimplantation of SSC and me-CH could be a useful strategy for reconstructing meniscus

New prefabricated support structure for TBM tunneling in complex strata of coal mines: engineering practice

Tunnel Boring Machines (TBMs) have been successfully applied in the excavation of deep shaft roadways in coal mines, yielding substantial socio-economic benefits. However, technical bottlenecks remain that hinder their further promotion and application. In response to the challenge of current support structures and techniques failing to simultaneously meet the requirements of support efficiency, strength, and construction costs, which impedes the full utilization of TBM speed advantages, a research team has developed a novel steel pipe segment assembly support structure. Large-scale model tests of the new prefabricated support structure were conducted to ascertain the deformation and failure patterns under loaded conditions, and the support structure was optimized based on the test results. Numerical simulations were performed to evaluate the reliability of the new support structure under TBM tunneling conditions. Industrial trials were subsequently conducted to field-test the feasibility of the new steel pipe segment support structure for TBM-excavated roadways in coal mines. The test results indicate that the maximum tensile strain of the surrounding rock is 803 με, and the deformation of the steel pipe support structure is less than 1 mm. The new support structure can be installed quickly, with the installation of one ring of segments (1.5 m) completed within 90 minutes, significantly enhancing the support strength in TBM-excavated roadways and the adaptability to strata conditions. This research provides a technical reference for further increasing the tunneling speed of coal mine roadways and ensuring the continuity of coal mining operations

Research Progress on Mechanism of Action of DHODH in Progression of Malignant Tumors

Dihydroorotate dehydrogenase (DHODH) is a flavin-dependent metabolic enzyme that oxidizes dihydroorotate acid to orotic acid in the de novo synthesis pathway of pyrimidine metabolism. DHODH is located in mitochondria, closely related to cellular oxidative phosphorylation, and an important suppressor of the ferroptosis pathway. This study investigates the influence of DHODH on the progression of malignant tumors, including its important role in the de novo synthesis of pyrimidine, oxidative phosphorylation, and ferroptosis. The objective is to present evidence that DHODH is a potential target for the clinical treatment of tumors

Towards EEG-Based Haptic Interaction within Virtual Environments

Current virtual environments (VE) enable perceiving haptic stimuli to facilitate 3D user interaction, but lack brain-interfacial contents. Using electroencephalography (EEG), we undertook a feasibility study on exploring event-related potential (ERP) patterns of the user's brain responses during haptic interaction within a VE. The interaction was flying a virtual drone along a curved transmission line to detect defects under the stimuli (e.g., force increase and/or vibrotactile cues). We found that there were variations in the peak amplitudes and latencies (as ERP patterns) of the responses at about 200 ms post the onset of the stimuli. The largest negative peak occurred during 200~400 ms after the onset in all vibration-related blocks. Moreover, the amplitudes and latencies of the peak were differentiable among the vibration-related blocks. These findings imply feasible decoding of the brain responses during haptic interaction within VEs

Comparative study of CT-guided radiofrequency and alcohol ablation in the treatment of primary hyperhidrosis

ObjectiveThis study compared the efficacy and complications of percutaneous radiofrequency ablation with anhydrous alcohol ablation of sympathetic nerves in treating hyperhidrosis of the head and palms.MethodsA retrospective analysis was conducted on 54 patients with primary hyperhidrosis in our department from June 2018 to June 2021, divided into a radiofrequency ablation group (30 cases) and an anhydrous alcohol ablation group (24 cases). Treatment outcomes were compared by analyzing the number of CT scans, effectiveness, and complications.ResultsIn the radiofrequency group, symptoms of bilateral hyperhidrosis significantly improved in 24 patients, with an 80% postoperative satisfaction rate. In the alcohol ablation group, symptoms significantly improved in 19 patients postoperatively, with a 79.2% satisfaction rate. There was no statistically significant difference in effectiveness or complications between the two groups (all P > 0.05). The number of CT scans in the radiofrequency group was 4.60 ± 0.56 and 6.08 ± 0.28 in the alcohol group, showing a statistically significant difference (P < 0.05).ConclusionThis study concluded that both percutaneous radiofrequency ablation and alcohol ablation are effective methods for hyperhidrosis treatment, with similar effectiveness and complication rates, but the radiofrequency ablation group required fewer CT scans

Comparison of the feasibility and validity of a one-level and a two-level erector spinae plane block combined with general anesthesia for patients undergoing lumbar surgery

BackgroundSpinal surgery causes severe postoperative pain. An erector spinae plane (ESP) block can relieve postoperative pain, but the optimal blocking method has not been defined. The aim of this study is to compare the feasibility of a one-level and a two-level lumbar ESP block and their effect on intraoperative and postoperative analgesia in lumbar spinal surgery.MethodsA total of 83 adult patients who were scheduled for posterior lumbar interbody fusion were randomly divided into two groups. Patients in Group I (n = 42) received an ultrasound-guided bilateral one-level ESP block with 0.3% ropivacaine, while patients in Group II (n = 41) received a bilateral two-level ESP block. Blocking effectiveness was evaluated, including whether a sensory block covered the surgical incision, sensory decrease in anterior thigh, and quadriceps strength decrease. Intraoperative anesthetic dosage, postoperative visual analogue scale scores of pain, opioid consumption, rescue analgesia, and opioid-related side effects were analyzed.ResultsOf the total number, 80 patients completed the clinical trial and were included in the analysis, with 40 in each group. The time to complete the ESP block was significantly longer in Group II than in Group I (16.0 [14.3, 17.0] min vs. 9.0 [8.3, 9.0] min, P = 0.000). The rate of the sensory block covering the surgical incision at 30 min was significantly higher in Group II than in Group I (100% [40/40] vs. 85.0% [34/40], P = 0.026). The rate of the sensory block in the anterior thigh was higher in Group II (43.8% [35/80] vs. 27.5% [22/80], P = 0.032), but the rate of quadriceps strength decrease did not differ significantly between the groups. The mean effect–site remifentanil concentration during intervertebral decompression was lower in Group II than in Group I (2.9 ± 0.3 ng/ml vs. 3.3 ± 0.5 ng/ml, P = 0.007).There were no significant differences between the groups in terms of intraoperative analgesic consumption, postoperative analgesic consumption, and postoperative VAS pain scores at rest and with movement within 24 h. There were no block failures, block-related complications, and postoperative infection.ConclusionsAmong patients undergoing posterior lumbar interbody fusion, the two-level ESP block provided a higher rate of coverage of the surgical incision by the sensory block when compared with the one-level method, without increasing the incidence of procedure-related complications. Clinical Trial Registrationwww.chictr.org.cn, identifier: ChiCTR210004359

Highly controllable and reliable ultra-thin Parylene deposition

Thanks to the excellent barrier property and fabrication accessibility, Parylene has been actively used in the microelectromechanical system. An ultra-thin Parylene film with thickness smaller than 100 nm is usually required to precisely tune the surface property of substrate or protect the functional unit. The commercially available regular Parylene deposition is a dimer mass determined chemical vapor deposition process with a high output (i.e. a low deposition precision in term of thickness control), around 1.6 μm/g (the ratio of film thickness to the loaded dimer mass) for the machine in the author’s lab. Therefore, it is hard to controllably and reliably prepare a Parylene film with thickness smaller than 100 nm, which requires a dimer mass less than 62.5 mg. This paper reported a method to prepare ultra-thin Parylene films with the nominal thickness down to 1 nm. A home-made deposition chamber was put inside and connected with the regular machine chamber through a microfabricated orifice with feature size smaller than 1 mm. According to the free molecular flow theory, the pressure inside the deposition chamber can be predictably and controllably reduced, thereby an ultra-low output of Parylene deposition, as low as 0.08 nm/g, was successfully obtained. The deposition precision was increased by 4 orders of magnitude compared to that of a direct Parylene deposition. This highly controllable and reliable ultra-thin Parylene deposition technique will find promising applications in flexible electronics and biomedical microdevices