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1.
Sci Rep ; 14(1): 6471, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38499624

ABSTRACT

Solar power is a renewable energy source, and its efficient development and utilization are important for achieving global carbon neutrality. However, partial shading conditions cause the output of PV systems to exhibit nonlinear and multipeak characteristics, resulting in a loss of output power. In this paper, we propose a novel Maximum Power Point Tracking (MPPT) technique for PV systems based on the Dung Beetle Optimization Algorithm (DBO) to maximize the output power of PV systems under various weather conditions. We performed a performance comparison analysis of the DBO technique with existing renowned MPPT techniques such as Squirrel Search Algorithm, Cuckoo search Optimization, Horse Herd Optimization Algorithm, Particle Swarm Optimization, Adaptive Factorized Particle Swarm Algorithm and Gray Wolf Optimization Hybrid Nelder-mead. The experimental validation is carried out on the HIL + RCP physical platform, which fully demonstrates the advantages of the DBO technique in terms of tracking speed and accuracy. The results show that the proposed DBO achieves 99.99% global maximum power point (GMPP) tracking efficiency, as well as a maximum improvement of 80% in convergence rate stabilization rate, and a maximum improvement of 8% in average power. A faster, more efficient and robust GMPP tracking performance is a significant contribution of the DBO controller.

2.
J Nanobiotechnology ; 19(1): 274, 2021 Sep 08.
Article in English | MEDLINE | ID: mdl-34496892

ABSTRACT

BACKGROUND: Spinal cord injury (SCI) is an inflammatory condition, and excessive adenosine triphosphate (ATP) is released into the extracellular space, which can be catabolized into adenosine by CD73. Extracellular vesicles have been designed as nano drug carriers in many diseases. However, their impacts on delivery of CD73 after SCI are not yet known. We aimed to construct CD73 modified extracellular vesicles and explore the anti-inflammatory effects after SCI. METHODS: CD73 engineered extracellular vesicles (CD73+ hucMSC-EVs) were firstly established, which were derived from human umbilical cord mesenchymal stem cells (hucMSCs) transduced by lentiviral vectors to upregulate the expression of CD73. Effects of CD73+ hucMSC-EVs on hydrolyzing ATP into adenosine were detected. The polarization of M2/M1 was verified by immunofluorescence. Furthermore, A2aR and A2bR inhibitors and A2bR knockdown cells were used to investigate the activated adenosine receptor. Biomarkers of microglia and levels of cAMP/PKA were also detected. Repetitively in vivo study, morphology staining, flow cytometry, cytokine analysis, and ELISA assay, were also applied for verifications. RESULTS: CD73+ hucMSC-EVs reduced concentration of ATP and promoted the level of adenosine. In vitro experiments, CD73+ hucMSC-EVs increased macrophages/microglia M2:M1 polarization, activated adenosine 2b receptor (A2bR), and then promoted cAMP/PKA signaling pathway. In mice using model of thoracic spinal cord contusion injury, CD73+ hucMSC-EVs improved the functional recovery after SCI through decreasing the content of ATP in cerebrospinal fluid and improving the polarization from M1 to M2 phenotype. Thus, the cascaded pro-inflammatory cytokines were downregulated, such as TNF-α, IL-1ß, and IL-6, while the anti-inflammatory cytokines were upregulated, such as IL-10 and IL-4. CONCLUSIONS: CD73+ hucMSC-EVs ameliorated inflammation after spinal cord injury by reducing extracellular ATP, promoting A2bR/cAMP/PKA pathway and M2/M1 polarization. CD73+ hucMSC-EVs might be promising nano drugs for clinical application in SCI therapy.


Subject(s)
5'-Nucleotidase/metabolism , Extracellular Vesicles/transplantation , Inflammation/therapy , Spinal Cord Injuries/pathology , Adenosine Triphosphate/metabolism , Animals , Cyclic AMP/metabolism , Cytokines/metabolism , Down-Regulation , Extracellular Vesicles/metabolism , Humans , Inflammation/etiology , Macrophages/cytology , Macrophages/metabolism , Male , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Mice , Mice, Inbred ICR , Proto-Oncogene Proteins c-akt/metabolism , RNA Interference , Receptor, Adenosine A2B/chemistry , Receptor, Adenosine A2B/genetics , Receptor, Adenosine A2B/metabolism , Signal Transduction , Spinal Cord Injuries/complications , Umbilical Cord/cytology
3.
Front Pharmacol ; 11: 348, 2020.
Article in English | MEDLINE | ID: mdl-32265718

ABSTRACT

Postmenopausal osteoporosis is caused by the deficiency of estrogen, which breaks bone homeostasis and induces levels of pro-inflammatory cytokines. Muscone is a potent anti-inflammatory agent and is used to treat bone fracture in traditional Chinese medicine. However, its anti-osteoclastogenic effects remain unclear. For in vitro study, morphology tests of osteoclastogenesis were firstly performed. And then, factors in RANK-induced NF-κB and MAPK pathways were examined by RT-PCR and Western blot, and the binding of TNF receptor-associated factor (TRAF)6 to RANK was inspected by coimmunoprecipitation and immunofluorescence staining. For in vivo experiments, C57BL/6 ovariectomized (OVX) mice were used for detection, including H&E staining, TRAP staining, and micro CT. As a result, muscone reduced OVX-induced bone loss in mice and osteoclast differentiation in vitro, by inhibiting TRAF6 binding to RANK, and then suppressed NF-κB and MAPK signaling pathways. The expression of the downstream biomarkers was finally inhibited, including NFATc1, CTR, TRAP, cathepsin K, and MMP-9. The inflammatory factors, TNF-a and IL-6, were also reduced by muscone. Taken together, muscone inhibited the binding of TRAF6 to RANK induced by RANKL, thus blocking NF-kB and MAPK pathways, and down-regulating related gene expression. Finally, muscone inhibited osteoclastogenesis and osteoclast function by blocking RANK-TRAF6 binding, as well as downstream signaling pathways in vitro. Muscone also reduced ovariectomy-induced bone loss in vivo.

4.
World Neurosurg ; 135: e43-e49, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31678438

ABSTRACT

OBJECTIVES: The present study introduced an electronic conductivity device (ECD) to reduce time of percutaneous transpedicular puncture and frequency of patient valid radiation exposure in percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP). METHODS: A randomized self-control clinical study was undertaken. Medical records of patients with vertebral compression fractures (VCFs) for bilateral PKP or PVP were collected, and each side was performed randomly with ECD or conventional trocar. RESULTS: We enrolled 61 patients (44 women, 17 men) with 75 vertebras with VCF. Compared with the conventional fluoroscopy group, significant reductions in puncture time (504.33 ± 152.03 vs. 652.68 ± 167.60 seconds; P < 0.001) and fluoroscopy frequency (5.11 ± 1.23 vs. 8.15 ± 1.83; P < 0.001) for each percutaneous puncture were observed in the ECD group. When compared with the VCFs ≤50% group, the 2 indexes in the VCFs >50% group were significantly increased. And in the ECD group, the learning curve in the VCFs >50% group showed a steeper decreasing trend than that in the VCFs ≤50% group. No complications were observed in any patient. CONCLUSIONS: ECD could reduce puncture time of percutaneous transpedicular puncture and exposure of radiation in PVP and PKP. ECD has more benefits in complicated transpedicular puncture in patients with vertebral compression >50%.


Subject(s)
Fractures, Compression/surgery , Osteoporotic Fractures/surgery , Punctures , Radiation Exposure/prevention & control , Spinal Fractures/surgery , Aged , Bone Cements , Electric Conductivity , Female , Humans , Male , Middle Aged , Vertebroplasty/methods
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