1.Optical properties and biomedical applications of gold nanorods
Yichen PENG ; Yuqian JIANG ; Chenjie FANG
International Journal of Biomedical Engineering 2021;44(2):151-156
In recent years, the research on gold nanoparticles has made great progress. Gold nanoparticles with different morphologies have good application prospects in drug delivery and tumor treatment. Some gold nanoparticles have entered the stage of clinical trials. Gold nanorods have become important research objects due to their special optical properties and photothermal treatment potential. In this paper, the optical properties and main applications of gold nanorods were reviewed. Gold nanorods have good surface modifiable properties and can be modified through surface ligand exchange to improve their biocompatibility. The photothermal properties of gold nanorods can be improved by adjusting the aspect ratio to adjust the surface plasmon resonance (SPR) peak to achieve near-infrared light excitation. These characteristics make gold nanorods show good application prospects in the detection of biological macromolecules, real-time imaging in vivo, and early diagnosis and treatment of tumors. Using gold nanorods as a carrier and modified with different targeting molecules can improve the targeting of its drug delivery system and reduce damage to normal cells, so as to realize the combined application of chemotherapy and photothermal therapy, and finally achieve a better therapeutic effect. Combining gold nanorods with stem cells or certain specific biomolecules can form a hybrid gold nanorod system which provides new ideas for further improving the efficiency of tumor treatment.
2.Role of LHPP in malignant tumor
Tiantian LI ; Min CHEN ; Yichen LIU ; Jie PENG ; Xiaofeng SHI
Journal of International Oncology 2021;48(7):420-423
Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is a highly conserved histidine phosphatase from worms to humans in evolution. Recent studies have shown that LHPP, as a tumor suppressor, can inhibit the proliferation, growth and migration of the cells and promote apoptosis by participating in the regulation of various cell signaling pathways and protein phosphorylation. Therefore, the deeply study on the mechanism of LHPP is helpful to explore the best diagnostic markers and therapeutic targets for related tumors, which is essential for improving the prognosis of related tumors.
3.Effect of transcutaneous electrical acupoint stimulation at Neiguan on dexmedetomidine-induced bradycardia in patients
Yanqiu LIU ; Xiaokui FU ; Guoping SONG ; Yu PENG ; Yichen MA ; Hao WU ; Hong GAO
Chinese Journal of Anesthesiology 2021;41(6):727-730
Objective:To evaluate the effect of transcutaneous electrical acupoint stimulation (TEAS) at Neiguan on dexmedetomidine-induced bradycardia in patients.Methods:Sixty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients, aged 20-50 yr, weighing 48-60 kg, scheduled for elective gynecological surgery under general anesthesia, were divided into 2 groups ( n=30 each) using a random number table method: control group (group C) and TEAS group (group T). Dexmedetomidine 1 μg/kg was infused intravenously over 10 min followed by intravenous infusion 0.5 μg·kg -1·min -1 in two groups, and the patients in group T simultaneously received TEAS (frequency 2/100 Hz, disperse-dense wave, intensity 5-10 mA according to the current that could be tolerated) at bilateral Neiguan acupoints.The stimulator was only connected, and no current was given in group C. Before the infusion of dexmedetomidine (T 0) and at 10 min of dexmedetomidine infusion (T 1), mean arterial pressure (MAP) and heart rate (HR) was recorded, and electrocardiogram (ECG) was collected to calculate the PR interval, QT interval, QT interval, Tp-e interval and index of cardiac electrophysiological balance (iCEB). The development of arrhythmia was recorded. Results:Compared with the baseline value at T 0, HR was significantly decreased, and QT interval and PR interval were prolonged at T 1 in two groups, and iCEB was increased, and Tp-e interval was prolonged at T 1 in group C ( P<0.05). Compared with group C, HR was significantly increased, PR interval and Tp-e interval were shortened at T 1, and the incidence of bradycardia and atrioventricular block was increased in group T ( P<0.05). Conclusion:TEAS at Neiguan can decrease the risk of bradycardia induced by dexmedetomidine, and the mechanism may be related to shortening atrioventricular conduction time and reducing heterogeneity of ventricular repolarization in patients.
4.Effect of Median Nerve Electrical Stimulation on Synaptic Plasticity in Ischemic Stroke Rats
Chengcai ZHANG ; Rong NING ; Na CHEN ; Yichen PENG ; Li ZHOU ; Xichen YANG ; Jingyi LU ; Pengyue ZHANG ; Rui LI
Journal of Kunming Medical University 2023;44(12):6-12
Objective To investigate the effects and mechanisms of median nerve electrical stimulation on synaptic plasticity in ischemic stroke rats.Methods 18 healthy male SD rats were randomly divided into Sham group(n = 6),ischemic stroke group(MCAO group,n = 6)and median nerve electrical stimulation group(MNES group,n = 6).The left middle cerebral artery occlusion model of rats was established by thread plug method.Thread plug was not inserted in sham group.The median nerve electrical stimulation group was given median nerve electrical stimulation intervention on the 3rd day after modeling,and intervention on the next day.After intervention for 7 times,behavioral detection,HE staining was used to detect median nerve injury.Nissl staining was used to detect cerebral infarction volume.Western blot was used for detection of the expression level of proteins related to synaptic plasticity,and electron microscopy was performed.Results HE staining showed that median nerve electrical stimulation did not cause damage to the median nerve in stroke rats,and the median nerve membrane was intact without obvious inflammatory cells.Compared with MCAO group,the neural function,motor function and coordination of the injured forelimb in MNES group were significantly improved(P<0.01).Compared with MCAO group,cerebral infarction volume in MNES group was significantly reduced(P<0.05),the pyknosis of Nissl bodies in ischemic penumbra decreased.Compared with MCAO group,the expression levels of synaptic plastication-related proteins PSD95 and synI in the cortex of MNES group were significantly up-regulated after median nerve electrical stimulation(P<0.05),the number of synapses in the ischemic cortex increased significantly(P<0.01).Conclusion Median nerve electrical stimulation is a safe and effective therapeutic measure to improve nerve function after stroke,and its mechanism is related to promoting synaptic plasticity.
5.Prognostic value of serum concentration of human soluble stromelysin-2 combined with left ventricular diastolic function for elderly patients with septic shock
Qianqian WANG ; Lingwei ZHANG ; Yichen GU ; Maoxian YANG ; Jiangang ZHU ; Peng SHEN
Chinese Journal of Geriatrics 2023;42(9):1070-1076
Objective:To explore the prognostic value of the serum concentration of human soluble stromelysin-2(sST2)combined with ultrasonic left ventricular diastolic function parameters for elderly patients with septic shock.Methods:This prospective study involved 150 elderly patients with septic shock admitted to the intensive care unit(ICU)of the First Hospital of Jiaxing between May 2019 and May 2022.Data on the following parameters were recorded on days 1, 3, 5, and 7 in the ICU: sST2 concentration, mitral early-diastolic inflow peak velocity(E), mitral late-diastolic inflow peak velocity(A), E/A ratio, early diastolic mitral annular velocity(e'), and E/e' ratio.According to the 28-day prognostic outcome obtained during follow-up, patients were divided into a survival group and a death group to compare differences in values of the above parameters between the two groups and at different time points.Logistic regression was used to analyze independent risk factors for 28-day mortality.The receiver operating characteristic(ROC)curve was used to analyze the predictive value for 28-day mortality, and further risk stratification was performed according to optimal cut-off values to compare differences in 28-day mortality under different risk stratification methods.The Kaplan-Meier survival curve was used to compare 28-day cumulative survival under different risk stratification methods and analyze the predictive value of the combination of the parameters for 28-day mortality.Results:On day 5 following ICU admission, e' was lower and E/e' and sST2 were higher in the death group than in the survival group.Univariate and multivariate Logistic regression analysis suggested that sST2(odds ratio: 1.010, P<0.001)was an independent risk factor for 28-day mortality in elderly patients with septic shock.sST2 had a sensitivity of 50.2%, a specificity of 79.1%, and an area under the curve of 0.660 for predicting 28-day mortality in patients with septic shock.The sST2 concentration was 89.3 μg/L on day 5 after ICU admission, which was the clinical cutoff point for predicting 28-day mortality.Based on the risk stratification of sST2 levels, the 28-day mortality rate was higher in the sST2>89.3 μg/L group than in the sST2≤89.3 μg/L group.Kaplan-Meier survival analysis showed that the 28-day cumulative survival rate was significantly lower in the sST2>89.3 μg/L group than in the sST2≤89.3 μg/L group(44.0% vs.66.7%, log-rank test: χ2=9.101, P=0.003).The receiver operating characteristic curve showed that the combination of sST2, e', and E/e' significantly improved the prediction efficiency of 28-day mortality in elderly patients with septic shock, with an area under the curve of 0.844, a sensitivity of 89.7%, and a specificity of 66.5%. Conclusions:sST2 is an independent risk factor for 28-day mortality in elderly patients with septic shock.When combined with e' and E/e', sST2 can more accurately evaluate the survival prognosis of these patients.
6.Analysis of epidemic characteristics of hand-foot-mouth disease Virus using circular distribution method
Lihua CHEN ; Xia PENG ; Erda ZHENG ; Tian HUANG ; Yichen JIA ; Linhui HAO ; Xiulian SHEN ; Jibo HE
Journal of Public Health and Preventive Medicine 2020;31(3):64-67
Objective To understand the epidemic characteristics of different virus types of hand, foot and mouth disease (HFMD) in Zhaotong City, and provide guidance and recommendations for the prevention and control of HFMD, and to analyze seasonal characteristics of different virus types of HFMD in Zhaotong City. Methods The epidemiological characteristics of different virus types of HFMD in Zhaotong City from 2014 to 2017 were analyzed using the concentration and circular distribution methods. Results The main pathogens detected were EV71, Cox A16 and other enteroviruses, which were 216, 182, and 294, respectively, accounting for 57.45%, 73.44%, and 67.11%. M was 0.86, indicating that EV71 had strong seasonality. The Rayleigh test showed statistically significant differences (Z = 99.53, P <0.001). ā = 157 °, the peak day of onset was May 10, similar to untyped (May 16), the peak period was April 21-June 1, and the epidemic period was April 1-June 21. Conclusion According to the incubation period of hand-foot-mouth disease and the period of time during which the vaccine develops protective effects, vaccination of hand-foot-mouth disease vaccine at the peak period has a good guiding significance for the timeliness and pertinence of vaccination.
7.Acute effects of air pollution on pulmonary function and exhaled nitric oxide in children in Shanghai
Jianhui GAO ; Yuhong WANG ; Yichen DING ; Lisha SHI ; Dong XU ; Limin LING ; Li PENG ; Lijun ZHANG
Shanghai Journal of Preventive Medicine 2024;36(3):241-248
ObjectiveTo investigate the acute effects of compound air pollution on children’s respiratory function. MethodsUsing panel group study design, 223 students in five classes of grade 4 from two primary schools (a, b) in Xuhui and Hongkou districts of Shanghai were randomly selected to measure pulmonary function and exhaled nitric oxide (FeNO). The first three tests were carried out from May to June in 2020, and the fourth test was carried out from September to December in 2021. At the same time, the daily and hourly mean values of PM2.5, PM10, SO2, NO2, O3 and CO was collected from the nearby air quality monitoring points of the two schools during the same period , as well as meteorological monitoring data (temperature, humidity, wind speed and atmospheric pressure). The linear mixed effect model was used to analyze the effects of air pollution on pulmonary function and respiratory inflammation in the summer. ResultsThe results of single pollutant model showed that PM2.5, PM10, SO2 and NO2 were positively correlated with FeNO, and the effect was reflected in lag0, lag1 and lag3 (P<0.05). PM2.5, PM10 and NO2 were negatively correlated with the changes of lung function FEF25%, FEF50%, FEF75%, FeF25%-75%, PEF, FVC, FEV1 and FEV1/FVC, and the effect was reflected in lag0 to lag3 days (P<0.05). The results of the dual pollutant model showed that the concentration changes of SO2 and NO2 were significantly correlated with the decrease of FEV1 when combined with O3 or PM2.5 (P<0.01), and the concentration changes of PM2.5 was significantly correlated with the increase of FeNO when O3, SO2 and NO2 were combined respectively (P<0.01). The effects of the dual pollutant model were greater than the effect of PM2.5 single pollutant model. ConclusionThe health effects of different air pollutants on children’s respiratory tract function indexes in summer are different. The combined effects of two pollutants on the lung function of children increased to different degrees. Although air pollution is light in summer, it still has an impact on children’s respiratory tract function index and inflammation index, and the combined effect of dual pollutants is more significant than that of single pollutant.
8.SARS-CoV-2 impairs the disassembly of stress granules and promotes ALS-associated amyloid aggregation.
Yichen LI ; Shuaiyao LU ; Jinge GU ; Wencheng XIA ; Shengnan ZHANG ; Shenqing ZHANG ; Yan WANG ; Chong ZHANG ; Yunpeng SUN ; Jian LEI ; Cong LIU ; Zhaoming SU ; Juntao YANG ; Xiaozhong PENG ; Dan LI
Protein & Cell 2022;13(8):602-614
The nucleocapsid (N) protein of SARS-CoV-2 has been reported to have a high ability of liquid-liquid phase separation, which enables its incorporation into stress granules (SGs) of host cells. However, whether SG invasion by N protein occurs in the scenario of SARS-CoV-2 infection is unknow, neither do we know its consequence. Here, we used SARS-CoV-2 to infect mammalian cells and observed the incorporation of N protein into SGs, which resulted in markedly impaired self-disassembly but stimulated cell cellular clearance of SGs. NMR experiments further showed that N protein binds to the SG-related amyloid proteins via non-specific transient interactions, which not only expedites the phase transition of these proteins to aberrant amyloid aggregation in vitro, but also promotes the aggregation of FUS with ALS-associated P525L mutation in cells. In addition, we found that ACE2 is not necessary for the infection of SARS-CoV-2 to mammalian cells. Our work indicates that SARS-CoV-2 infection can impair the disassembly of host SGs and promote the aggregation of SG-related amyloid proteins, which may lead to an increased risk of neurodegeneration.
Amyloidogenic Proteins/metabolism*
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Amyotrophic Lateral Sclerosis/genetics*
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Animals
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COVID-19
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Cytoplasmic Granules/metabolism*
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Mammals
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SARS-CoV-2
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Stress Granules