1.Molecular mechanisms and biology significance of polysaccharide recognition by the immune system
Chinese Journal of Immunology 1985;0(01):-
As monosaccharide polymers,polysaccharides are widely distributed in nature,they are found in microorganisms,plants and animal cells and tissues.Glycosylation is of importance to maintain the structural stability and biological activity of protein molecules in eukaryotic cells.Polysaccharides represent the most important antigens recognized by immune system.The innate immune system senses invading microbes via their pathogen-associated molecular patterns,using pattern-recognition receptors on the surface of innate immune cells,many of which are polysaccharides uniquely expressed in certain microorganisms.Polysaccharides can also be processed intracellularly and presented to ??-T cells by MHC molecules.Polysaccharides can activate B lymphocytes,with or without T cell help,and induce production of specific antibodies.Amongst the polysaccharide-specific antibodies in human sera,some are products of adaptive humoral responses against microbial infection and others autoantibodies to glycan epitopes of host cells.Patients with autoimmune disorders tend to have higher titers of antibodies against various glycans.Immune clearance of senescence cells depends on the recognition of altered glycan epitopes on cell surface.Modification of glycan epitopes on tumour cell surface is at least partially responsible for activating antitumor immunity.Specific recognition of polysaccharides by the immune system is of importance to immunological defence,autoimmunity,anti-tumour immunity and immunological homeostasis,it will be the new focus of immunology research in the near future.
2.Optimizing the Ground Substance of Antipyretic Suppositories for Children
Long DAI ; Guofei LIU ; Xiaoming ZHOU
Traditional Chinese Drug Research & Clinical Pharmacology 2000;0(06):-
Half-synthetic oil ester (of fruit of a cubeb litsea tree) Suppositories. The speed of medicine release was 85% within 20min in S-40 Suppositories and nearly 100% within 30 min. Conclusion: S-40 can be used as the ground substance for the antipyretic Suppositories for children.
3.Study on the effects of air disinfection by three methods
Dachun FANG ; Guixing DAI ; Xiaoming WU
Chinese Journal of Disease Control & Prevention 2001;5(1):18-20
Objective To study the effects of air disinfect ion by three methods. Methods Air was disinfected by ultraviol et rays, pentadialdchyde and ozone, efficiency of disinfection was eval uated b y three different disinfection methods using synchronous sampling after and b efo re disinfected. Results The peak of the bacteria background by precussion method was 10 o'clock, by the ballistic method was 9 o'clock and by the petri dish method was 10 o'clock before disinfected. Three disinfect ion methods were significantly different, efficiency of disi nfection of pentadialdchyde was the highest when it was evaluated by the precuss io n method, and recovery of bacteria was 43.4%~55.8% after disinfected 3 h our s; effect of pentadialdchyde was better than that of the ballistic method, and r ecovery of bacte ria was 21.8%~35.7% after disinfected 3 hours; effect of ultra violet ra ys was better than that of the petri dish method, and recovery of bacteria was 4 2.1%~60.6% after disinfected 3 hours. But their differences were not significan t. In t he course of experiment, temperature and relative humidity have a negative impac t on the ultraviolet ray's efficiency and almost have no impact on others. Conclusions Disinfection method of the ultraviolet rays could be rep laced by disinfection method of pentadialdchyde and ozone.
4.A preliminary study on the proliferation of endothelial cells of human hemangioma
Xiaoming DAI ; Longjiang LI ; Yuming WEN
Journal of Practical Stomatology 2001;0(03):-
Objective: To study the role of simian virus 40 large T antigen(SV40LTag) and telomeras in the proliferation of endothelial cells in hemangioma. Methods: The expression of SV40LTag was examined in 100 cases of hemangioma with immunohistochemistry, telomerase activity and telomeric length were measured by RT-PCR based telomeric repeat amplification protocol(TRAP) assay, telomeric restriction fragment (TRF) analysis and chemiluminescence in situ hybridization in 50 cases of hemangioma and 10 of squamous cell carcinoma. A sample of embryonic kidney endothelia was used as the contrdol. Results: SV40LTag expression was observed in 45 out off the 100 cases of hemangioma. Telomerase expression was found in 27 out off the 50 cases of hemangioma and all the 10 of squamous cell carcinoma. The telomeric length in hemangioma varied from 6.8 to 13.2 kb, 10.5-13.5 kb in squamous cell carcinoma and 12.4 kb in embryonic kidney endothelia. Conclusion: Transformation of endothelia by simian virus 40 may contribute to the occurring of hemangioma, telomerase may play a role in the proliferation of the endothelial cells in hemangioma.
5.A study on the relationship between reactive hyperplasia of the draining lymph nodes and oral cancer micrometastasis
Hua LIU ; Longjiang LI ; Xiaoming DAI
Journal of Practical Stomatology 2001;0(03):-
Objective:To investigate the relationship between reactive hyperplasia of the draining lymph nodes and oral cancer micrometastasis.Methods:The specimens was taken from 12 patients suffered from oral squamous cell carcinoma,who accepted inpatient care in West China College of Stomatology,Sichuan University.There were totally 233 lymph nodes,and all the specimens were divided into normal,reactive hyperplasia and metastasis groups by pathological diagnosis.Immunohistochemistry method was used to inspect micrometastasis in the two prior groups,and the data were analyzed with SPSS 10.0.Results:25 lymph nodes were detected metastasis,79 were reactive hyperplasia,and 129 were normal.Normal mucosa,squamous cell carcinoma and metastatic lymph nodes were positive to keratin,and there were 29 and 12 specimens with micrometastasis in reactive hyperplasia and normal lymph nodes separately.Conclusion:Micrometastasis occured on the reactive hyperplasia lymph node in the oral cancer draining area is easier than that on the normal one.
6.Protective effect of estrogen on rat′s retina injured by transient ischemia-reperfusion
Yan DAI ; Xiaoming CHEN ; Xiaohu CHEN
Chinese Journal of Ocular Fundus Diseases 2001;0(03):-
Objective To evaluate the protective effect of estrogen on survival of retinal ganglion cells (RGCs) after transient retinal ischemia-reperfusion (RIR) in rats. Methods RIR was induced in 60 ovariectomized adult rats (OVX) by increasing intraocular pressure via an intracameral catheter. All of the rats were divided into two groups randomly: in experimental group, the rats underwent a subcutaneous injection with 17?-estrodiol(100 ?g/kg) 2 hours before retinal ischemia; and in the control group, saline water was injected correspondingly. The number of RGCs and the thickness of the inner retinal layers were mesured by HE staining method before and 12, 24, 48, and 72 hours after reperfusion. TdT-mediated biotin-dUTP nick end labelling (TUNEL) staining technique was used to examine the apoptosis of RGCs. Results Twenty-four and 48 hours after reperfusion, the number of apoptotic cells in experimental group was obvious lower than that in the control group( P
7.Intenational breakthroughs in critical care medicine 2020
Chenxi LIU ; Xiaoming DAI ; Wei HUANG
Chinese Critical Care Medicine 2021;33(1):5-9
The main progress in international critical care medicine in 2020 are: the reflections on the mandatory of implementation of the 1-hour cluster treatment strategy for sepsis are still continuing; the "metabolic resuscitation" therapy, represented by large dose of vitamin C, failed to yield positive results; the global epidemic of coronavirus disease 2019 (COVID-19) continues to spread, with evidences indicating Dexamethasone, Remdesivir or interferon β-1b (IFNβ-1b), Lopinavir/Ritonavir and ribavirin as promising therapy; conservative oxygen therapy did not exert positive effects neither for mechanical ventilated patients nor for acute respiratory distress syndrome (ARDS) patient; the concept of lung- and diaphragm-protective mechanical ventilation illuminates a new opportunity to potentially improve clinical outcomes for critically ill patients; there was no positive evidence for stress ulcer prophylaxis and timing of endoscopy for severe acute upper gastrointestinal bleeding; early initiation of renal-replacement therapy (RRT) for critically ill patients with acute kidney injury (AKI) has not shown positive effect. At last, artificial intelligence (AI) has shown good potential in identifying ARDS phenotypes and early predicting sepsis.
8.Effect of Tongsaimai Tablet on experimental atherosclerosis in rats
Yuwei YANG ; Chen HU ; Huimin BIAN ; Xiaoming DAI
Chinese Traditional Patent Medicine 1992;0(03):-
AIM:To investigate the effect of TSM tablet on rat's atherosclerotic model's endothelial cell and explore the mechanism of it.METHODS:Fifty Wistar rats were randomly assigned into five groups:control group,model group,Simvastatin group,TSM high group,TSM low group.All groups were fed with high fat diet and vitamin D3 except for control group to set up atherosclerosis model.After 12 weeks we detected circle endothelial cell,angiotensinⅡ and electron microscopy morphology of arteries.RESULTS:Level of circulating enthelia cell(CEC) and AngⅡin model rats were significantly higher.TSM can reduce level of the CEC and AngⅡ.Model group rat's artery endothelial cells were severely damaged under electron microscopy;rat's artery endothelial cellsin TSM group were basically intact and its internal elastic membrane was unbroken on it thickness was even,without significant lesion.CONCLUSION:TSM by reducing the number of CEC,the level of AngⅡ used for experimental atherosclerotic endothelial cell in rats has the protective effect.
9.Construction and evaluation of intracerebral capsular hemorrhage models in rats
Rufei DAI ; Jun CAI ; Ning LIU ; Fengyi ZHU ; Xiaoming LI
Chinese Journal of Tissue Engineering Research 2006;10(42):211-213
BACKGROUND: A stable and exact animal model is the necessary tool and basis for studying hemorrhagic cerebrovascular diseases.OBJECTIVE: To establish and evaluate the intracerebral capsular hemorrhage models in rats.DESIGN: A randomized and controlled animal experiment.SETTING: Second Hospital Affiliated to Xuzhou Medical College; First Hospital Affiliated to Nanjing Medical University.MATERIALS: This experiment was carried out in the animal experimental center of Nanjing Medical University during May to November 2002.Totally 35 SD rats were randomized into two groups: experimental group (n=30) and sham-operation group (n=5).METHODS: ① Autoblood was injected into the intracerebral capsule of rats to create intracerebral capsule hemorrhage models with stereotaxy in the experiment group. ②Scoring was conducted according to 5-point neurological scoring criteria from ZeaLonga, somatic sensation and motor function of rats were observed. ③Somatosensory evoked potential(SEP) of rats was detected pre- and post-operation under anesthetic state. ④ After determination of SEP, the rats were sacrificed under anesthetic state. Brains were taken out to made slices, then sections were stained with haematoxylin and eosin. Changes in haematoma and histomorphology were observed at the largest focus under optical microscope.MAIN OUTCOME MEASURES: ①Nerve function scoring; ②Latent period of various waves of SEP; ③ Observation of brain tissue morphology.RESULTS: Totally 35 rats entered the stage of result analysis. ①Appearance of obvious paralysis of the rats suggested the modeling was successful. The successful rate of this experiment was 93.3%(28/30). Significant difference existed in neurological scoring between experimental group [(2.74±0.46)points] and sham-operation group (0 point)(P<0.05). ②SEP showed that the latent periods of various waves of experimental group after operation were significantly delayed than those before operation and those of sham-operation group [P1: (15.72±0.78) ms, (10.69±0.52) ms, (10.73±0.48) ms;Nl: (17.95±1.27) ms,(13.21±1.31) ms, (13.34±1.27) ms;N2:(21.16±1.62) ms, (15.42±1.46) ms,(15.58±1.44) ms;N3:(24.86±1.58) ms, (18.72±1.76) ms, (18.99±1.67) ms,P<0.05]. ③In the shamoperation group, a few red blood cells were scattered in the peripheral area of needle channel were found, but hemorrhagic focus was not; In the experimental group, irregular or oval blood clots presented in the left internal capsule area. In about a low-fold visual field, brain tissue in the surrounding of hemorrhagic focus was loosened and swelled, and pathological changes were obviously severer than those in the sham-operation group.CONCLUSION: Intracerebral capsular hemorrhage induced by injection of autoblood with stereotaxy is more close to clinical situation, and it is easy to operate and has good reproducibility.
10.Calcium caused calcium release causes a vascular smooth muscle cell line A10 cells apoptosis
Yulin WU ; Bingliang MA ; Xiaoming DAI ; Linlin CHEN
Chinese Journal of Clinical Pharmacology and Therapeutics 2006;11(7):789-796
AIM: To investigate the apoptosis of a vascular smooth muscle cell line A10 caused by mild K+ depolarization. METHODS: Apoptosis was evaluated by nuclear staining, DNA fragmentation gel electrophoresis and propidium iodide-stained flow cytometry. Mitochondrial transmembrane potential (Δψm) was measured by flow cytometry. RESULTS: K+ depolarization caused dose correlated A10 cells apoptosis; nifedipine, BAPTA/AM, ryanodine inhibited the cytotoxic effect of K+ completely.The combination use of nifedipine and cyclosporin A made it clear that mitochondria was involved in the apoptosis of A10 cells,and Δψm measurement further confirmed this speculation; A10 apoptosis caused by K+ depolarization was not influenced by heparin or Zn2+,a effective capacitative calcium entry(CCE) blocker. CONCLUSION: Ca2+ entry through voltage-dependent ca channels increases intracytoplasm Ca2+, then triggers further Ca2+ release from endoplasmic reticulum via ryanodine receptor, and the microdomains of elevated intracytoplasm Ca2+ are sensed by adjacent mitochondria, which ultimately lead to cell apoptosis.