Mitochondrial NDUFA4L2 attenuates the apoptosis of nucleus pulposus cells induced by oxidative stress via the inhibition of mitophagy

Wen-Ning Xu,Huo-Liang Zheng,Run-Ze Yang,Tao Liu,Wei Yu,Xin-Feng Zheng,Bo Li,Sheng-Dan Jiang,Lei-Sheng Jiang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

The main pathological mechanism of intervertebral disc degeneration (IVDD) is the programmed apoptosis of nucleus pulposus (NP) cells. Oxidative stress is a significant cause of IVDD. Whether mitophagy is induced by strong oxidative stress in IVDD remains to be determined. This study aimed to investigate the relationship between oxidative stress and mitophagy and to better understand the mechanism of IVDD in vivo and in vitro. To this end, we obtained primary NP cells from the human NP and subsequently exposed them to TBHP. We observed that oxidative stress induced mitophagy to cause apoptosis in NP cells, and we suppressed mitophagy and found that NP cells were protected against apoptosis. Interestingly, TBHP resulted in mitophagy through the inhibition of the HIF-1α/NDUFA4L2 pathway. Therefore, the upregulation of mitochondrial NDUFA4L2 restricted mitophagy induced by oxidative stress. Furthermore, the expression levels of HIF-1α and NDUFA4L2 were decreased in human IVDD. In conclusion, these results demonstrated that the upregulation of NDUFA4L2 ameliorated the apoptosis of NP cells by repressing excessive mitophagy, which ultimately alleviated IVDD. These findings show for the first time that NDUFA4L2 and mitophagy may be potential therapeutic targets for IVDD.

Evaluation on Dry Sliding Wear Behavior of (TiB+TiC)/Ti- 6Al-4V Matrix Composite

Zi-Run Yang,Hai-Xiang Huan,Cui-Feng Jiang,Wen-Min Li,Xue-Ran Liu,류성기 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.8

The dry sliding wear tests were performed for 10 vol.% (TiB+TiC)/Ti-6Al-4V matrix composites at various test conditions. The morphology and phases of worn surfaces and cross-sectional surfaces were investigated by using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The wear loss of composites with the increase of load, but the wear behavior got more complex when the sliding speed and ambient temperature got higher. Low wear loss was achieved at lower sliding speed with higher temperature or higher sliding speed with lower temperature. A tribo-layer was always formed on worn surface during testing. It possessed different features and thus presented different effects during sliding wear. Meanwhile, the TiB and TiC particulates strengthened the Ti-6Al- 4V matrix, which increased the thermal stability of composites and postponed the occurrence of severe plastic deformation. In the mild wear region, those particulates could directly resist wear by reducing adhesive wear. In the steady stage, fractured TiB and TiC particulates participated in forming the tribo-layer together with wear debris, which effectively hindered the plastic deformation and thermal softening of the matrix. Experiment results suggest that the existence of different characteristic tribo-layers would result in the variation of wear behavior.

Fabrication of polyacrylic acid-based composite binders with strong binding forces on copper foils for silicon anodes in lithium-ion batteries

Ting-Ting Su,Wen-Feng Ren,Jiang-Meng Yuan,Ke Wang,Bing-Yu Chi,Run-Cang Sun 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.109 No.-

The commercial application of silicon (Si) anodes with high theoretical capacity is hampered by the poorcyclic stability because the huge volume change of Si during discharge/charge processes results in thepulverization of electrode materials and the electric contact loss of electrode materials with copper(Cu) foils. Binders play an important role for adhering active materials and conductive additives togetheronto Cu foils. Herein, we design and develop a three-dimensional networked composite binder (PAA-co-SN) via an amidation reaction between polyacrylic acid (PAA) and thiourea (SN). The granular anchors(CuxS) are constructed at the interface between PAA-co-SN binders and Cu foils, resulting from the reactionof S and Cu during the drying processes of Si electrodes. When used as binders for Si nanoparticles,they exhibit stable cyclic performance (1580 mAh g1 after 500 cycles). The anchoring mechanismbetween composite binders and Cu foils provides a strategy for the improvement of electrochemicalproperties of Si-based anodes for lithium-ion batteries.

Test on the anchoring components of steel shear keys in precast shear walls

Shao-Dong Shen,Peng Pan,Wen-Feng Li,Qi-Song Miao,Run-Hua Gong 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.24 No.6

Prefabricated reinforced-concrete shear walls are used extensively in building structures because they are convenient to construct and environmentally sustainable. To make large walls easier to transport, they are divided into smaller segments and then assembled at the construction site using a variety of connection methods. The present paper proposes a precast shear wall assembled using steel shear keys, wherein the shear keys are fixed on the embedded steel plates of adjacent wall segments by combined plug and fillet welding. The anchoring strength of shear keys is known to affect the mechanical properties of the wall segments. Loading tests were therefore performed to observe the behavior of precast shear wall specimens with different anchoring components for shear keys. The specimen with insufficient strength of anchoring components was found to have reduced stiffness and lateral resistance. Conversely, an extremely high anchoring strength led to a short-column effect at the base of the wall segments and low deformation ability. Finally, for practical engineering purposes, a design approach involving the safety coefficient of anchoring components for steel shear keys is suggested.

Prevalence, Risk Factors, and Psychological Effects of Primary Nocturnal Enuresis in Chinese Young Adults

Hui Jie Hu,Zhen Wei Zhang,Yu Liang,Yan Yan Luo,Qi Feng Dou,Cui Ping Song,Hui Min Zhang,Ying Zhao,Guang Run Tian,Ke Zhang,Qiu Fang Mao,Jing Gui Song,Soren Rittig,Jian Guo Wen 대한배뇨장애요실금학회 2021 International Neurourology Journal Vol.25 No.1

Purpose: This study aimed to investigate the prevalence, risk factors, and effects of primary nocturnal enuresis (PNE) on physical and mental health in young adults in mainland China. Methods: An anonymous questionnaire was used to collect information including the sociodemographic characteristics, history of PNE, family history, daytime voiding symptoms, Pittsburgh Sleep Quality Index (PSQI) scores, Self-Esteem Scale (SES), and Self-Rating Depression Scale (SDS). A total of 22,500 university students from 23 provinces and 368 cities in mainland China were included. Results: In total, 21,082 questionnaires were collected, and 20,345 of them qualified for statistical analysis. The PNE prevalence was 1.17%, and the distribution of monosymptomatic nocturnal enuresis (MNE) and nonmonosymptomatic nocturnal enuresis (NMNE) was 66.1% and 33.9%, respectively. In total, 28% of respondents with PNE reported bedwetting daily, 31.6% between 1 and 7 times weekly, and 40.4% between 1 and 4 times monthly; 80% of PNE cases had no history of treatment. The prevalence of PNE in patients with a family history, frequency, urgency, urinary incontinence, and recurrent urinary tract infections was significantly higher than in those without these conditions (P<0.001). PNE was significantly correlated with the PSQI total score (sleep quality) (P=0.011). The SES score was lower and the SDS was higher (P<0.001) in the PNE group than in those without PNE. Conclusions: In mainland China, the PNE prevalence among young adults was found to be high, and PNE had significant effects on physical and mental health. Risk factors included a family history, daytime voiding symptoms, and lack of treatment.

Effects of graphite additives in electrolytes on the microstructure and corrosion resistance of Alumina PEO coatings

Guo-Hua Lv,Huan Chen,Wei-Chao Gu,Wen-Ran Feng,Li Li,Er-Wu Niu,Xian-Hui Zhang,Si-Ze Yang 한국물리학회 2009 Current Applied Physics Vol.9 No.3

In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved. In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved.