1.Excitatory toxicity of glutamate on meningothelial cells of optic nerve sheaths and its oxidative stress mechanism
Xiaorong, XIN ; Tianxiang, GONG ; Ying, HONG ; Hong, DANG
Chinese Journal of Experimental Ophthalmology 2017;35(5):432-437
Background Meningothelial cells (MECs) occupy the predominant cell component of barrier between optic nerve and the cerebral spinal fluid,and any change of cerebral fluid components probably affects the MECs function and further impairs the optic nerve.Objective This study was designed to investigate the influence of glutamate,a potentially excitotoxic amino acid,to the functional changes of MECs and provide a theoretical evidence for clarifying the mechanism of optic nerve disorders.Methods Human MECs strains were cultured in vitro and prepared into cell suspension.The cells were inoculated to 96-well plates with the densities of 1 × 104/we11.The glutamate of 100,200,400,600,800 and 1 000 μmol/L was added into medium for 12,24,36,48 and 72 hours,respectively,and the cultured cells without glutamate were used as normal control group.MTS assay was employed to measure the proliferative rate (absorbency) of the cells.The regularly cultured MECs were divided into 600 μmol/L glutamate-treated group and normal control group and the cells were treated for 12 and 24 hours respectively,and the expression of superoxide dismutase (SOD) mRNA and heat shock protein 90 (HSP90) mRNA in the cells was detected by real-time PCR;the level of total anti-oxidative capacity (T-AOC) of the cells was processed by enzyme linked immunosorbent assay (ELISA),and the reactive oxygen species (ROS) production was determined by DCFH-DA probe.Results Cultured MECs grew well and formed 80% confluence after 72 hours culture.The proliferative rate of the cells were gradually decreased with the increase of glutamate dose and the lapse of affected time,with significant differences among different concentrations of glutamate and various time points (F tration =52.501,P<0.001;Ftime =8.505,P<0.001).The relative expression level of SOD mRNA was significantly reduced in the glutamate-treated group compared with the normal control group in both 24 hours and 48 hours after culture (t =20.278,t =16.724,both at P<0.001),and the expression of HSP90 mRNA in the cells was significantly lower in the glutamate-treated group than that in the normal control group in 24 hours after culture (t =5.065,P =0.002).No significant difference was found in T-AOC activity between glutamate-treated group and normal control group in 24 hours after culture ([30.835±2.094] nmol/(min · L) vs.[32.873±2.317] nmol/(min · L)) (t=1.599,P =1.414).In 48 hours after culture,T-AOC activity was (29.561 ± 1.831) nmol/(min · L) in the glutamate-treated group,which was significantly lower in comparison with normal control group (33.680±2.039) nmol/(min · L)(t =3.682,P =0.004).Fluorescence staining showed that the intensity of green fluorescence of ROS in MECs in the normal control group was weaker than that in the glutamate-treated group under the immunofluorescense microscope.The ROS level was 48.110± 1.712 and 40.982± 1.853 at 24 hours and 48 hours in the glutamate-treated cells,and which was significantly elevated in comparison with 36.608± 1.009 and 37.153 ± 1.424 in the normal control group (t=14.178,P<0.001;t=4.012,P=0.002).Conclusions Glutamate inhibits the proliferation of MECs in vitro,and excitatory toxicity of glutamate on MECs probably is associated with oxidative stress response.
2.Effects of hypoxia on production of ATP and expression of mitochrome C in human meningothelial cells as the cerebral fluid-optic nerve barrier
Xiaorong, XIN ; Tianxiang, GONG ; Li, ZHAO ; Xinzhang, LI
Chinese Journal of Experimental Ophthalmology 2014;32(1):28-31
Background BackgroundMeningothelial cells (MECs) are major cell type in the meningeal sheath around optic nerve,which form a fluid barrier between optic nerve and the cerebral spinal fluid.The impairment of the cerebral fluid-optic nerve barrier probably affects the balance of cerebral fluid components.Currently,the investigation on the role of MECs in neuropathy is less performed.Objective This study attempted to explore hypoxia-induced function changes of MECs,and to shed a new clus for the future research of optic nerve disorders.Methods Human MECs strains were cultured in vitro and cell suspension was prepared with the cell densities of 2.5 ×103/hole,5.0× 103/hole and 1 x 104 /hole,respectively.The suspensions of 100 μl were separately collected to incubate in 96-well plates and cultivated for 2 days in 21% O2(normoxia group) or 1% O2(hypoxia group).MTS was used to detect and compare the proliferative value (A490) of MECs between the normoxia group and the hypoxia group.The changes of MECs diameter and volume were measured by CASY1 assay.ATP product in the cells after MECs exposed to different oxygen environments with or without substrate (100 mmol/L pyruvate and 100 mmol/L malate) for 1,2 days were assayed by Luminometer method.The expression and distribution of cytochrome C in the cells of the normoxia group and the hypoxia group were determined by immunofluorescence.Results A490 of MECs in the 2.5× 103/hole,5.0× 103/hole and 1 × 104/hole were 0.399±0.009,0.393±0.009 and 0.496±0.026 in the hypoxia group,which were lower than 0.424±0.131,0.413±0.111 and 0.537±0.021 in the normoxia group (t =3.777,P =0.004 ; t =3.251,P =0.009 ; t =3.037,P =0.013).Compared with the normoxia group,the diameter and volume were significantly increased in the hypoxia group ([20.970 ±0.127] μm vs.[21.198 ±0.048] μm,t =-3.762,P=0.006; [5805±73] fl vs.[6026±106] fl,t=-4.124,P=0.002).ATP products were (0.900±0.225)mmol/(L· g) and (0.952± 0.075) mmol/(L · g) in the hypoxia group and the hypoxia+substrate group,which were significantly lower than (1.389±0.145) mmol/(L · g) and (1.401±0.122) mmol/(L · g) in the normoxia group and the normoxia +substrate group (P =0.001,0.002,0.001).Immunofluorescense staining showed that the green fluorescence of cytochrome C located at mitochondria of MECs in the normoxia group,but in the hypoxia group,cytochrome C distributed in the cytoplasm extensively.Conclusions Hypoxia induces malfunction of MECs,which might impact the intact of the cerebral spinal fluid-optic nerve barrier and therefore influence the microenvironment of the subarachnoid space and neuronal function.
3.Preoperative ascending aorta diameter and prognosis analysis of patients with acute type A aortic dissection
Yuduo WU ; Ming GONG ; Lizhong SUN ; Lianjun HUANG ; Yongmin LIU ; Junming ZHU ; Tianxiang GU ; Ruixin FAN ; Ximing QIAN ; Yihua HE ; Hongjia ZHANG
Chinese Journal of Thoracic and Cardiovascular Surgery 2022;38(4):235-240
Objective:To investigate the preoperative ascending aorta diameter in patients with acute type A aortic dissection in the Chinese population, compares and analyze the differences in preoperative blood biomarkers, and evaluate the impact of the preoperative ascending aorta diameter in this part of patients on the short-term prognosis of patients.Methods:A collection of 641 patients with acute type A aortic dissection who were enrolled in the " Acute Aortic Syndrome High-Risk Early Warning and Intervention Study" project from January 2018 to January 2020 were collected. Divide the patients into two groups (group Ⅰ<55 mm, group Ⅱ≥55 mm) according to the preventive intervention value of ascending aorta diameter recommended by the guideline for studying preoperative ascending aorta diameter difference in blood biomarkers and the influence of ascending aorta diameter on the short-term prognosis of patients. All patients had CT scans to assess the diameter of the ascending aorta before operation.Results:In this study, all patients with acute type A aortic dissection had a mean preoperative ascending aorta diameter of (46.9±9.7)mm. The preoperative ascending aorta diameter of all patients was less than 55 mm, accounted for 84.1%. Male patients were more likely to have aortic dissection than females; most patients' age was less than 60 years old. The preoperative blood inflammatory index counts were higher in the ascending aorta diameter ≥55 mm group. However, the long-term prognosis of patients with different ascending aorta diameters before surgery was not apparent in this study. The preoperative survival rate and short-term survival rate of patients with ascending aorta diameter <55 mm were higher than those of other groups, but the difference was not statistically significant.Conclusion:In patients with acute type A aortic dissection, the diameter of the ascending aorta is usually less than 55 mm. Moreover, the blood inflammatory index counts are high in the preoperative ascending aorta diameter ≥55 mm group. Meanwhile, patients with smaller ascending aorta diameter have better survival rate and short-term prognosis.
4.Platelet antibody screening and crossmatch in Chengdu in 2019
Xixi TAN ; Xiwei WEI ; Tianxiang GONG ; Ying HONG ; Zhiru LI ; Meng LI ; Xuemei FU ; Shuping LI
Chinese Journal of Blood Transfusion 2021;34(4):382-385
【Objective】 To analyze the status of the platelet antibody screening and crossmatch in Chengdu in 2019, so as to further improve the corresponding detection strategy to improve the clinical transfusion efficacy. 【Methods】 The patients underwent platelet antibody crossmatch in Chengdu Blood Center in 2019 were selected as research objects Platelet antibody screening and crossmatch were performed by solid-phase agglutination technique, and the sample size, the incidence of platelet antibod, age, blood group, seasonal chracteristics, hospital levels, ratio of repeated crossmatch and the transfusion efficacy were analyzed. 【Results】 321 treatment doses of matched platelets after 259 occasions of crossmatch relative to 85 patients were provided. The positive rate of platelet antibody was 87.06%. 64.71% of the patients were over 40 years old, the proportion of ABO group in crossmatch samples was O>A>B>AB, and the crossmatch cases increased each quarter gradually. All samples were provided by tertiary hospitals. 52.94% of the patients needed crossmatch at least twice, and the efficacy rate of matched platelets transfusion was 63.64%. 【Conclusion】 The platelet transfusion efficacy could by improved by platelet antibody screening and crossmatch, so as to avoid the waste of platelets, which deserves active promotion in clinical.
5.Preoperative risk factors for the onset of acute Stanford type A aortic dissection in a multicenter study: A retrospective cohort study
Yuduo WU ; Ming GONG ; Lizhong SUN ; Lianjun HUANG ; Yongmin LIU ; Junming ZHU ; Tianxiang GU ; Ruixin FAN ; Ximing QIAN ; Hongjia ZHANG
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2022;29(08):986-991
Objective To evaluate the preoperative risk factors for acute Stanford type A aortic dissection (ASTAAD) patients in our country by collecting multi-center data. Methods We consecutively enrolled 700 patients who underwent surgery for ASTAAD in the multi-center hospital database from January 2018 to January 2020. According to the ascending aorta size (AAS), the patients were divided into two groups: a group AAS≥55 mm and a group AAS< 55 mm. Univariate and multivariate logistic regression analyses were used to investigate the related preoperative risk factors for the onset of ASTAAD. Results According to the exclusion criteria, a total of 621 patients were finally enrolled, including 453 males and 168 females with an average age of 48.24±11.51 years, and 509 (81.94%) patients had AAS< 55 mm. Univariate and multivariate statistical analyses showed that smoking, hypertension, preoperative cardiac troponin I, and left ventricular ejection fraction were related to the occurrence of ASTAAD. The mortality rate of the patient during hospitalization was 13.04% (81 patients). Conclusion In clinical practice, various preoperative risk factors affect ASTAAD patients, which should be paid attention to. Comprehensive evaluation and an individualized analysis of patients and timely prevention and intervention improve patients' survival rate.