The mitochondrial unfolded protein response (UPRmt) protects against osteoarthritis

Zhou Zhibin,Lu Jiajia,Yang Mei,Cai Jiao,Fu Qiang,Ma Jun,Zhu Lei 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

The mitochondrial unfolded protein response (UPRmt) is a mitochondrial-to-nuclear signaling pathway that is activated to maintain mitochondrial function when there is an accumulation of misfolded proteins within mitochondria. Mitochondrial function is essential for chondrocyte homeostasis, and mitochondrial dysfunction is a characteristic of osteoarthritis (OA). However, the role of the UPRmt in OA remains unclear. In the present study, the level of the UPRmt was examined in primary mouse chondrocytes subjected to different stresses and in the articular cartilage of OA model mice and OA patients. The relationship between UPRmt activation and OA progression was studied. The UPRmt was induced in primary mouse chondrocytes subjected to diverse stresses and in the cartilage of OA mice. Enhancement of the UPRmt with nicotinamide riboside (NR) significantly improved mitochondrial function, reduced chondrocyte death, attenuated OA pain, and ameliorated OA progression, and the protective effects decreased significantly in chondrocyte-specific Atf5 knockout (ATF5f/fCol2a1-CreERT2) mice. UPRmt induction was also identified in the articular cartilage of OA patients and was associated with reduced chondrocyte death, less severe hip pain, and lower levels of inflammation in synovial fluid. These findings identify the induction of the UPRmt in primary mouse chondrocytes exposed to pathological stresses and in the articular cartilage of OA model mice and OA patients. Enhancement of the UPRmt ameliorates OA progression, suggesting that the UPRmt exerts a protective effect against OA and may be a potential diagnostic and therapeutic strategy for OA.

Preparation of Modified Nano-SiO₂ Oil Dispersion System and the Stability of Its O/W Emulsion

Zhibin Zhou,Jiexiang Wang 한국고분자학회 2016 폴리머 Vol.40 No.2

Nano-SiO₂ was organically modified with silane coupling agent-KH570 to prepare the modified Nano-SiO2 oil dispersion system. By increasing the dosage of KH570, the ζ-potential (absolute value) and the char yield values decreased gradually. When KH570 was 5%, the maximum contact angle with water reached 79.8°. Then, the modified Nano-SiO₂ was composed with petroleum sulfonate (PS) and its ability of reducing the O/W interfacial tension was measured. The results showed that, O/W interfacial tension reduced to about 5.86×10<SUP>-3</SUP> mN/m when the Nano-SiO₂ and petroleum sulfonate composite was mixed with the mass fraction of 0.2:0.3%. The emulsion stability coefficient was 2.15 after 120 min which was the minimum. It indicated that this compounded system had the best emulsifying ability because Nano-SiO₂ particles were dragged onto the O/W interface by the PS molecules to improve the intensity of O/W interface.

The association of urinary uric acid excretion with ambulatory blood pressure values in patients with chronic kidney disease

Ying Xu,Xun Zhou,Yuqi Zheng,Haochen Guan,Chensheng Fu,Jing Xiao,Zhibin Ye 대한고혈압학회 2020 Clinical Hypertension Vol.26 No.2

Background: To analyze the association between hypertension and urinary uric acid excretion in patients with chronic kidney disease (CKD). Methods: We screened 87 patients who had been admitted at the Dept of Nephrology, Huadong hospital between April 2017 to April 2019 who had completed 24-h ambulatory blood pressure monitoring and retained 24-h urine biochemical test specimens, thirty adult patients (age ≤ 65 years) with CKD 1–2 stages were recruited in the study. Pearson’s correlation analysis and multiple linear regression analysis were used to study the correlation of urinary uric acid excretion with ambulatory blood pressure values and the association of morning mean diastolic pressure (mMDP), night mean diastolic pressure (nMDP) and CV of dMSP (coefficient of variation of day mean systolic pressure) with fractional excretion of uric acid (FEua) and uric acid clearance rate (Cur). Independent T test was used to compare the differences of blood pressure values in FEua1 (FEua< 6.0%) and FEua2 (FEua≥6.0%) or Cur1 (Cur < 6.2 ml/min/1.73 m2 ) and Cur2 (Cur ≥ 6.2 ml/min/1.73m2 ) groups according to the median of FEua or Cur, respectively. Results: After adjusting for confounding factors, multiple linear regression analysis showed that FEua was positively associated with the mMDP and nMDP, Cur was positively associated with CV of dMSP. Levels of mMDP and nMDP in FEua1 group was lower than that in FEua2 group (both P < 0.05), level of CV of dMSP in Cur2 group were higher than that in Cur1 group (P < 0.01). Conclusions: We demonstrated that there is a positive correlation of FEua with morning and night mean diastolic pressure separately and Cur is positively related to CV of dMSP in CKD population. Monitoring the trend of urinary uric acid, may have a role in the early detection for hypertension or relative risks in the population of CKD.

Analytical and Numerical Investigation of Overstrength Factors for Very Short Shear Links in EBFs

Shujun Hu,Jingang Xiong,Qiang Zhou,Zhibin Lin 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.11

Shear links are key components in the Eccentrically Braced Frames (EBFs) that act as a structural fuse by dissipating seismic energy during severe earthquakes. Specification AISC 341, which is frequently used in the seismic design of steel structures, prescribes a constant overstrength factor of 1.50 for shear links. However, a few existing experimental results indicated that the overstrength of very short shear links with length ratio lower than 1.0 are much greater than required. In this paper, five basic factors influencing the overstrength of very short shear links are summarized as follows: web-ultimate-to-yield-shear-strength ratio, lengthto- stiffener-spacing ratio, flange-to-web-area ratio, flange-to-web-strength ratio, length-to-depth ratio. A numerical investigation with a detailed Finite Element (FE) model, verified by a comparison with existing experimental results, is conducted to investigate the combined effects of these five basic factors on the overstrength of very short shear links. Then, a new numerical model for predicting the overstrength value is proposed based on the FE analysis results and existing available experimental data by using the numerical fitting method, and it shows good agreement.

Does National Distance Affect Different Industries in Different Ways? A Test of the Ghemawat CAGE Model

Hak Cho Kim,Jong-Wook Kwon,Zhibin Zhou,Ji Hyun Heo 한국무역학회 2019 Journal of Korea trade Vol.23 No.7

Purpose - This study empirically investigated whether national distances (Cultural, Administrative, Geographic and Economic distance) have different effects on industries in different ways. Design/methodology - The empirical model utilized industry level export trade data to examine the differentiated effects of each national distance. By using direct measurement and covering 75 countries, this paper analyzes the effect of distances in different industries. More specifically, this study classified the industries into a more-sensitive/less-sensitive scale. Findings - The empirical results showed the complicated impacts of national distances on trade. Trade in industries that are more sensitive to cultural and administrative distances was not decreased as greatly as trade in industries that are less sensitive to cultural and administrative distances. Also, industries that are more sensitive to geographic distance showed a stronger negative impact on trade than less sensitive industries. Lastly, economic distance decreased trade for industries that are more sensitive to economic distance, while economic distance did not significantly increase trade for industries that are less sensitive to economic distance. Originality/value - As the first study to empirically find out whether national distance has different effects on industries, this study updated the measurements of national distance.