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.The update of the relationship between nonalcoholic fatty liver disease and atherosclerosis
Chinese Journal of Endocrinology and Metabolism 2011;27(9):784-786
Nonalcoholic fatty liver disease (NAFLD) is associated with obesity, type 2 diabetes,dyslipidemia, hypertension, and metabolic syndrome.It likely represents hepatic manifestation of metabolic syndrome. The prevalence of NAFLD has been estimated to be 20%-30% in the general population. However, it is much higher in type 2 diabetic patients. Several epidemiological studies indicate that NAFLD is linked to an increased risk of cardiovascular disease( CVD), which is independent of underlying cardiometabolic risk factors. This suggests that NAFLD may also be actively involved in the pathogenesis. The possible molecular mediators linking NAFLD and atherosclerosis(AS) include the release of pro-atherogenic factors by oxidative stress and inflammation as well as atherogenic dyslipidemia, abnormal adipose factors, and insulin resistance, finally aggravating progression of CVD. In this article, the relationship and possible mechanisms between NAFLD and AS are reviewed.
3.The serum level of leptin before and after rosiglitazone administration in type 2 diabetes
Ye GAO ; Lan HE ; Xiaoming WANG
Journal of Xi'an Jiaotong University(Medical Sciences) 1982;0(01):-
Objective To observe leptin level before and after rosiglitazone administration and to explore the possible mechanism of rosiglitazone's improving insulin sensitivity.Methods A total of 30 patients newly diagnosed with type 2 diabetes were separated into three groups at random,and treated with rosiglitazone(4mg/d),metform(750mg/d) and gliclazide(160mg/d),respectively.Serum leptin,insulin and GHbA1c were measured after 12 weeks.Results After 12 weeks' treatment,the fasting glucose and GHbA1c in each group declined sharply,while free insulin did not change.The leptin level in rosiglitazone group decreased and insulin sensitivity was improved after administration,but there was no change in metformin and sulfonylureas groups.Conclusion Leptin may play a role in rosiglitazone's mediating the insulin-sensitizing effects.
4.Clinical significance of Qmax and residual urine in benign prostatic hyperplasia
Hongfei GAO ; Dongwen WANG ; Xiaoming CAO
Chinese Journal of Urology 2013;34(8):579-581
Objective To investigate the significance of Qmax and residual urine in evaluation of bladder function in the patients with benign prostatic hyperplasia (BPH).Methods The clinical data of 61 patients with BPH and 20 healthy persons in control group were evaluated.Bladder function,uroflowmetry and ultrasonic residual urine measurement were performed in the 2 groups.The correlation between Q max and residual urine in BPH group was investigated.Results There was significant difference in Qmax between the BPH group and control group (8 vs.21 ml/s,u=-6.090,P=0.007).There was significant difference in residual urine between the 2 groups (60 vs.9 ml,u =-6.718,P=0.005).And there was a negtive correlation between residual urine and Qmax in BPH group (r=-0.366,P=0.009).Conclusion It is useful to measure the Qmax and residual urine in evaluation of bladder function affected by bladder outlet obstruction caused by BPH.
5.Research Progress of Automatic Sleep Staging Based on Electroencephalogram Signals.
Qunxia GAO ; Jing ZHOU ; Xiaoming WU
Journal of Biomedical Engineering 2015;32(5):1155-1159
The research of sleep staging is not only a basis of diagnosing sleep related diseases but also the precondition of evaluating sleep quality, and has important clinical significance. In recent years, the research of automatic sleep staging based on computer has become a hot spot and got some achievements. The basic knowledge of sleep staging and electroencephalogram (EEG) is introduced in this paper. Then, feature extraction and pattern recognition, two key technologies for automatic sleep staging, are discussed in detail. Wavelet transform and Hilbert-Huang transform, two methods for feature extraction, are compared. Artificial neural network and support vector machine (SVM), two methods for pattern recognition are discussed. In the end, the research status of this field is summarized, and development trends of next phase are pointed out.
Electroencephalography
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Humans
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Neural Networks (Computer)
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Sleep Stages
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Support Vector Machine
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Wavelet Analysis
6.Advances on interventional molecular imaging
Jun GAO ; Feng ZHANG ; Xiaoming YANG
Chinese Journal of Clinical Oncology 2016;43(11):457-463
Recent advancements on interventional molecular imaging aimed to further complement the advantages of two imaging fields, namely, interventional radiology and molecular imaging. Interventional molecular imaging significantly improved the early diag-nosis of cancer, local treatment, and monitoring of tumor treatments. Interventional radiology has continuously extended the capabili-ties of the currently available molecular imaging techniques to (i) obtain deep-seated targets;(ii) thoroughly examine small targets;(iii) precisely guide the delivery of non-targeted imaging tracers or therapeutics;and (iv) selectively enhance the effectiveness of targeted imaging and treatment with high accuracy. Molecular imaging has been used to guide interventional therapies and assess the thera-peutic efficacies of medical interventions. The continuous efforts on interventional molecular imaging extend molecular imaging from benches or small animal laboratories to large animal suites and ultimately to certain clinical applications in humans and enhance the diagnosis and treatment of cancer.
7.Influence of L-arginine on hypoxia-ischemia brain injury in dogs after circulatory arrest and resuscitation
Yong GAO ; Gang WU ; Xiaoming ZOU
Medical Journal of Chinese People's Liberation Army 2001;0(11):-
Objective To study the effects of deep hypothermia and L-arginine(NO precursor) pretreatment on cerebral protection after circulatory arrest and resuscitation in a canine model. Methods Ten healthy adult dogs of both sexes, weighing 14.45?2.3kg, were randomly divided into two groups(n=5): sham treatment group and L-arginine pretreatment group. Extracorporeal circulation was established routinely,circulatory arrest was induced when the nasopharyngeal temperature was reduced to 18℃, then the animals were resuscitated 90min later with extracorporeal circulation. SjvO2 was measured at 30min before circulatory arrest, 0min, 45min, 90min after circulatory arrest and at 60minutes after resuscitation. The ultrastructure changes in cerabral cortex were observed with transmission electron microscope (HITACHI 7500). The brain water content was also determined after the dogs were sacrificed. Results SjvO2 had decreased obviously after circulatory arrest, attaining the lowest level in CA 90min.After resuscitation it increased again in both groups. The levels of SjvO2 in dogs of L-arginine pretreatment group were markedly higher than that of control group at 45min and 90min after circulatory arrest (P
8.Determination of zofenopril and its active metabolite zofenoprilat by a new derivative LC-MS method and their pharmacokinetics in healthy Chinese volunteers
Fei WU ; Fang GAO ; Li DING ; Xiaoming MAO ; Pengcheng MA
Journal of China Pharmaceutical University 2009;40(4):353-358
Aim: A new derivative LC-MS method was developed for the simultaneous determination of zofenopril and its active metabolite zofenoprilat to investigate the pharmacokinetic characteristics of zofenopril and zofenopri-lat in healthy Chinese volunteers after single and multiple oral doses of zofenopril calcium tablets. Methods: Ten Chinese healthy volunteers were given three single oral doses of 15,30, and 60 mg, respectively, and consecutively the multiple doses of 30 mg. The concentration and pharmacokinetic parameters of both the parent drug and the active metabolite were simultaneously determined by derivative LC-MS method using p-bromophenacyl bromide (p-BPB) as the derivative reagent. Results: After the single oral administrations of 15, 30, and 60 mg of zofeno-pril calcium, there was no significant difference in the t_(1/2) of both zofenopril and zofenoprilat among the three do-ses. The values of AUC_(0-24h) and c_(max) for both zofenopril and zofenoprilat showed the good linearities to the dosage over the dose range from 15 mg to 60 mg. There were no significant differences in AUC_(0-24h) and c_(max) for both com-pounds between female and male volunteers. After multiple oral administration( 30 mg once daily for 6 days ), the average steady state plasma concentration( c_(av)) for zofenopril was (5. 07 ±1. 06) ng/mL with the degree of fluctu-ation (DF) of 14. 26 ± 2. 94. The c_(av) for zofenoprilat was (6. 28 ± 1. 87) ng/mL with the DF of 11. 61 ±4. 68. The accumulation index values for zofenopril and zofenoprilat were 0. 94 ± 0. 31 and 0. 83±0. 13, respec-tively. Conclusion: Both zofenopril and zofenoprilat were demonstrated of linear kinetics after single administra-tion and showed no accumulation after multiple administration of the test zofenopril calcium tablets. There was significant difference in the pharmacokinetic characteristics for zofenopril calcium between healthy Chinese and European volunteers.
9.Effects of acteoside on expression of caspase-3 in cerebral cortex of mouse models of Alzheimer’s disease
Xiaoming PENG ; Li GAO ; Shixia HUO ; Ming YAN
Chinese Pharmacological Bulletin 2014;(12):1763-1768
Aim To investigate the effect of acteoside (AS)on the expression of caspase-3 in cerebral cortex of mouse models of Alzheimer’s disease(AD).Meth-ods Kunming (KM)strain mice were assigned into control group,model group,positive control group (VitE)and acteoside group.Every group was induced by a combination of D-galactose(i.p.60mg·kg -1 · d -1 )and AlCl3 (i.g.5mg·kg -1 ·d -1 )for 60ds ex-cept for control group,then mice were treated by dif-ferent concentrations(30,60,1 20 mg·kg -1 ·d -1 )of acteoside for 30ds.During the time,mice were in-duced continuously by a combination of D-galactose and AlCl3 .The learning and memory of mice were de-tected by step-down test,the activity of AChE in serum and brain of mice was measured by chemical colorime-try,the structure changes in cerebral cortex were ob-served by HE staining,and the expression of caspase-3 in cerebral cortex was analyzed through the immunohis-tochemical staining.Results Compared with model group,acteoside could improve the learning and mem-ory abilities(P <0.05 or P <0.01 ),decrease the ac-tivity of AChE in serum and brain(P <0.05 or P <0.01 ),and improve the morphology and number of neuron in cerebral cortex(P <0.01 ).Moreover,acte-oside could significantly inhibit the expression of caspase-3 in cerebral cortex (P <0.05,P <0.01 ). Conclusion Acteoside has significantly protective effects on brain damage of mice induced by a combina-tion of D-galactose and AlCl3 , and it′s protective mechanism probably relate to inhibiting the expression of caspase-3 and maintainings the normal morphology and number of neuron in cerebral cortex.
10.Protective Effects of Acteoside on PC12 Cell Injury Induced by Glutamate
Xiaoming PENG ; Shixia HUO ; Li GAO ; Yan HE ; Ming YAN
Herald of Medicine 2015;(3):302-305
Objective To investigate the effect of acteoside on injury PC12 cells induced by glutamate. Methods PC12 cells were assigned into normal control group, model control group, positive drug group and acteoside(AS) treated group. Every group was treated by 1. 5 mmol·L-1 glutamate for 24 hours except for the control group, and the injury was antagonized by 10 μmol·L-1 Vit E and acteoside at different concentration(15. 625, 31. 25, 62. 5, 125 and 250 μmol·L-1 ). Cell morphology was observed by inverted microscope, cell survival was determined with MTT, LDH activity was measured by enzyme label kit, the MDA content and SOD activity were measured by TBA kit and WST kit, and the ROS was measured by Elisa kit. Results Compared with the model control group, all doses of acteoside could significantly improve the PC12 cell morphology and survival (P<0. 05), inhibit LDH activity and production of MDA and ROS (P<0. 05), increase the activity of SOD (P<0. 05), except for the lowest dose group. Conclusion Acteoside has protective effects on PC12 cells injured by glutamate.