Protective effect of cilostazol on vascular injury in rats with acute ischemic stroke complicated with chronic renal failure

Sun Ru,Gu Qun,Zhang Xufeng,Zeng Ruiqi,Chen Dan,Yao Jingjing,Min Jingjing 한국독성학회 2024 Toxicological Research Vol.40 No.2

Chronic renal failure (CRF) resulting in vascular calcification, which does damage to blood vessels and endothelium, is an independent risk factor for stroke. It has been reported that cilostazol has a protective effect on the focal cerebral ischemic infarct. However, its impact on vascular injury in CRF combined stroke and its molecular protection mechanism have not been investigated. In this study, we carried out the effect of cilostazol on CRF combined stroke rats, and the results confirmed that it improved the neurobehavior, renal function as well as pathologic changes in both the kidney and brain. In addition, the inflammation and oxidative stress factors in the kidney and brain were suppressed. Moreover, the rates of brain edema and infarction were decreased. The injured brain-blood barrier (BBB) was recovered with less Evans blue extravasation and more expressions of zonula occludens-1(ZO-1) and occludin. More cerebral blood flow (CBF) in the ipsilateral hemisphere and more expression of CD31 and vascular endothelial growth factor (VEGF) in brain and kidney were found in the cilostazol group. Furthermore, cell apoptosis and cell autophagy became less, on the contrary, proteins of vascular endothelial growth factor receptor 2 (VEGFR2) after the cilostazol treatment were increased. More importantly, this protective effect is related to the pathway of Janus Kinase (JAK)/signal transducer and activator of transcription 3 (STAT3), mammalian target of rapamycin (mTOR), and the hypoxia inducible factor-1α (HIF-1α). In conclusion, our results confirmed that cilostazol exerted a protective effect on the brain and kidney function, specifically in vascular injury, oxidative stress, cell apoptosis, cell autophagy, and inflammation response in CRF combined with stroke rats which were related to the upregulation of JAK/STAT3/mTOR signal pathway.

Human Leptin Protein Induces Proliferation of A549 Cells via Inhibition of PKR-Like ER Kinase and Activating Transcription Factor-6 Mediated Apoptosis

Qun Lai,Yan Sun 연세대학교의과대학 2013 Yonsei medical journal Vol.54 No.6

Purpose: To investigate the anti-apoptotic mechanism of leptin in non-small cell lung cancer. Materials and Methods: The influences of leptin on apoptosis were investigated,analyzing the mechanism that triggers growth of A549 cells. The effects of leptin on cell proliferation were examined by XTT analysis. Leptin, C/EBP homologous protein (CHOP), phosphorylated-PKR-like ER kinase (p-Perk), inositol requiring proteins-1, spliced X-box transcription factor-1 (XBP1), cleaved activating transcription factor-6 (ATF6), eukaryotic translation initiation factor-2α, caspase-12 and CHOP protein were detected in four groups by western blot, and endoplasmic reticulum (ER) stress related mRNA were detected by reverse transcription PCR. Results: The expression of leptin in A549 and leptin transfected cells inhibited cisplatin activated ER stress-associated mRNA transcription and protein activation. Two ER stress unfolded protein response pathways, PERK and ATF6, were involved, and XBP1 and tumor necrosis factor receptor-associated factor 2 (TRAF2) were increased significantly when treated with cisplatin in A549-siRNA against leptin cells. Furthermore, CHOP expression was inhibited upon leptin expression in A549, LPT-PeP and LPT-EX cells. Conclusion: Leptin serves as an important factor that promotes the growth of A549 cells through blocking ER stress-mediated pathways. This blocking is triggered by p-Perk and ATF6 via inhibition of CHOP expression.

Electrophysiological and alarm behavioral responses of Solenopsis invicta Buren (Hymenoptera: Formicidae) to alkoxypyrazines

Yan Sun,Kai-Min Shao,Yongyue Lu,Qun-Hui Shi,Wen-Kai Wang,Li Chen 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

The red imported fire ant, Solenopsis invicta produces an alarm pheromone component, 2-ethyl-3,6- dimethylpyrazine, and responds to its pyrazine analogs in a similar manner but at varied detection thresholds. Herein, the responses of fire ant workers by electroantennogram (EAG) and behavior were tested with twelve structurally-related oxygen-containing pyrazines (alkoxypyrazines) and the synthetic alarm pheromone. All tested compounds elicited a dose-dependent EAG response, with S. invicta responding greatest to the synthetic alarmpheromone. Chemical structure of pyrazines influenced the EAG response but not always alarmbehavioral response. Among the 13 tested compounds, 7 compounds displayed significantly greater EAG response than 2- isopropyl-3-methoxypyrazine and 2-ethoxy-3-isopropylpyrazine at the dose of 1000 μg. Four of these 7 compounds, 2-ethyl-3,6-dimethylpyrazine, 2-methoxy-3-methylpyrazine, 2-ethoxy-3(5 or 6)-methylpyrazine, and 2-chloro-3-methoxypyrazinewith characteristic substituents on pyrazine ringwere further subjected to bait discovery bioassay.Hotdog bait containing pyrazines attracted significantlymore fire antworkers in the first 15-min period, resulting in quicker recruitment to food block than hexane control. The potential of using alkoxypyrazines in fire ant control is discussed.

Adaptive Dynamic Surface Control for Spacecraft Terminal Safe Approach with Input Saturation Based on Tracking Differentiator

Guan-Qun Wu,Shen-Min Song,Jing-Guang Sun 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.3

This thesis studies the spacecraft terminal safe approach control problem considering input saturation. Based on the spacecraft relative motion model and sphere collision avoidance potential function, an anti-saturation controller and an adaptive finite-time anti-saturation controller using dynamic surface control(DSC) are presented for the situations of known and unknown upper bound of external disturbances respectively, which can guarantee that no collisions happen in the tracking process. The second-order tracking differentiator is introduced to design the controllers, which avoids the differential of the virtual control signal and ensures the tracking performance of system output signals. Meanwhile, the auxiliary system is introduced to handle input saturation. Lyapunov stability theory is adopted to prove that the states of system under the designed controllers are uniformly ultimately bounded and practical finite-time stable respectively, and the chaser spacecraft can approach to the desired position without collision. The numerical simulation results demonstrate that the chaser spacecraft using the designed controllers can realize terminal safe approach to target spacecraft, which further illustrate the effectiveness of the proposed controllers.

High-yield production of few-layer boron nanosheets for efficient electrocatalytic N₂ reduction

Fan, Qun,Choi, Changhyeok,Yan, Chao,Liu, Yongchao,Qiu, Jieshan,Hong, Song,Jung, Yousung,Sun, Zhenyu The Royal Society of Chemistry 2019 Chemical communications Vol.55 No.29

<P>We report ambient electrochemical N2 fixation at low overpotentials by using two-dimensional (2D) β-boron. The metal-free catalyst afforded both an excellent NH3 yield rate and faradaic efficiency, approximately two times higher than those of bulk boron. We found that several binding sites, especially those involving icosahedral boron in the 2D material, can indeed catalyze N2 reduction efficiently with strong N2 adsorption, thus benefiting initial activation.</P>

산란계에 있어서 Stilbestrol 과 Vitamin D 급여효과에 대한 시험

오선균 한국축산학회 1960 한국축산학회지 Vol.2 No.1

The first egg laying day of White Leghorn hen which was hatched is the long-day season, May, June, and July, is over than 180 days(general standard) and it's egg production rate is low, although the hen is fully motored. This experiment was conducted to gee the increase of phosphoprotein, vitellin, by feeding diethylstilbestrol on layer and the increase of calcium and phosphorus absorption from feeds through mucous membrane of small intestine by feeding vitamin D₂. Owing to the short-daylight, cloud, fog, and rain, winter has less ultraviolet ray. Because of the above reason, this experiment was practiced 30days in winter. Results : There were no significant differences between the number of laid eggs, total weight of laid eggs, body weight, and the amount of feed take of the experiment group and that of the control group. Although the aim of this experiment was to increase the egg production, there were no effect. We found three difficulties in this experiment: experiment term was too short, ability of used hen was too low, and the number of used hen was too few to get the definite result.

Utility of VEGF and sVEGFR-1 in Bronchoalveolar Lavage Fluid for Differential Diagnosis of Primary Lung Cancer

Cao, Chao,Sun, Shi-Fang,Lv, Dan,Chen, Zhong-Bo,Ding, Qun-Li,Deng, Zai-Chun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Published data have shown that the levels of vascular endothelial growth factor (VEGF) and soluble VEGF receptor-1 (sVEGFR-1) in plasma and pleural effusion might be usefulness for lung cancer diagnosis. Here, we performed a prospective study to investigate the utility of VEGF and sVEGFR-1 in bronchoalveolar lavage fluid (BALF) for differential diagnosis of primary lung cancer. A total of 56 patients with solitary pulmonary massed by chest radiograph or CT screening were enrolled in this study. BALF and plasma samples were obtained from all patients and analyzed for VEGF and sVEGFR-1 using a commercially available sandwich ELISA kit. The results showed that the levels of VEGF in BALF were significantly higher in patients with a malignant pulmonary mass compared with patients with a benign mass (P < 0.001). However, no significant difference of sVEGFR-1 in BALF was found between malignant and non-malignant groups (P = 0.43). With a cut-off value of 214 pg/ml, VEGF showed a sensitivity and specificity of 81.8% and 84.2%, respectively, in predicting the malignant nature of a solitary pulmonary mass. Our study suggests that VEGF is significantly increased in BALF among patients with lung cancer than in benign diseases. Measurement of VEGF in BALF might be helpful for differential diagnosis of primary lung cancer.

Microscopic Mechanisms and Acoustic Emission Characteristics of Sandy Mudstone under Different Water Saturations

Xiao-ming Sun,Fu-kun Shi,Ming-qun Zhu,Jia-xu Ding,Lin-sen He,Zhi-hu Li,Tong Zhang,Cheng-yu Miao 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

In order to study the damage mechanism of surrounding rocks under water-rock coupling, an experimental study on the microscopic law of water absorption and mechanics of sandy mudstone was carried out in the sandy mudstone stratum of Wanfu coal mine in Shandong, China. The results indicate that the strength of sandy mudstone exhibits three stages of relative softening, rapid softening, and decelerated softening. The speed of water molecules entering the microscopic pore structure was analyzed based on the percentage of water molecules in the pore structure. The acoustic emission energy release process is divided into energy accumulation stage, stable release stage and intense release stage. With the increase of water content saturation,  (Spectral width of the multifractal spectrum) tends to decrease and the distribution of events is gradually uniform. The action of water gradually expands and penetrates the cracks and pores inside the sandy mudstone, which makes f (Frequency of occurrence of the signal) change from negative to positive values.

Fast terminal sliding mode tracking control of hypersonic vehicles based on non-homogeneous disturbance observer

Jing-Guang Sun,Shen-Min Song,Hai-Tao Chen,Guan-Qun Wu 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.6

The tracking control problem of hypersonic vehicles is studied and analyzed in this paper using terminalsliding mode control method (TSMC) and non-homogeneous disturbance observer(NHDO) considering parametricuncertainty and external disturbances. Non-singular terminal sliding mode controller is provided based on NHDO. The key idea is that the NHDO is adopted to estimate the aerodynamic uncertainties and external disturbancessimultaneously, which can enhance the robustness of the system and lower the gain of the switch controller. Rigorousstability analysis for the closed-loop system is given via Lyapunov stability theory, which proves that thesystem states are always bounded even during the estimation process when the estimation error is not zero. Thesliding manifold can be reached in finite time and the tracking errors can converge to zero asymptotically. Numericalsimulations are conducted with the longitudinal nonlinear dynamic model of hypersonic vehicles to verify theeffectiveness and robustness of the designed controller.

Exact and approximate solutions for free vibrations of continuous partialinteraction composite beams

Kai Q. Sun,Nan Zhang,Qun X. Zhu,Xiao Liu 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.44 No.4

An exact dynamic analytical method for free vibrations of continuous partial-interaction composite beams is proposed based on the Timoshenko beam theory. The main advantage of this method is that the independent shear deformations and rotary inertia of sub-beams are considered, which is more in line with the reality. Therefore, the accuracy of eigenfrequencies obtained by this method is significantly improved, especially for higher order modes, compared to the existing methods where the rotary angles of both sub-beams are assumed to be equal irrespective of the differences in the shear stiffness of each sub-beam. Furthermore, the solutions obtained by the proposed method are exact owing to no introduction of approximated displacement and force fields in the derivation. In addition, an exact analytical solution for the case of simply supported is obtained. Based on this, an approximate expression for the fundamental frequency of continuous partial-interaction composite beams is also proposed, which is useful for practical engineering applications. Finally, the practicability and effectiveness of the proposed method and the approximate expression are explored using numerical and experimental examples; The influence factors including the interfacial interaction, shear modulus ratio, span-to-depth ratio, and side-to-main span length ratio on the eigenfrequencies are presented and discussed in detail.