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find Keyword "alpha" 72 results
  • Research of Effective Network of Emotion Electroencephalogram Based on Sparse Bayesian Network

    Exploring the functional network during the interaction between emotion and cognition is an important way to reveal the underlying neural connections in the brain. Sparse Bayesian network (SBN) has been used to analyze causal characteristics of brain regions and has gradually been applied to the research of brain network. In this study, we got theta band and alpha band from emotion electroencephalogram (EEG) of 22 subjects, constructed effective networks of different arousal, and analyzed measurements of complex network including degree, average clustering coefficient and characteristic path length. We found that: ① compared with EEG signal of low arousal, left middle temporal extensively interacted with other regions in high arousal, while right superior frontal interacted less; ② average clustering coefficient was higher in high arousal and characteristic path length was shorter in low arousal.

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  • Measurement and significance of serum interferon-γ, tumor necrosis factor-α and interleukin-6 in patients with uveitis

    Objective To examine the levels of interferon-gamma; (INF-gamma;), tumor necrosis factor-alpha; (TNF-alpha;) and interleukin-6(IL-6) in serum of patients with acute uveitis before and after treatment, and to explore the possible roles of those cytokines in the initiation and progression of the uveitis. Methods A series of 75 patients with acute uveitis,and 30 healthy persons from our hospital were investigated. The levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase and convalescent phase were measured by the enzymelinked immunosorbent assay. Result The serum levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase were significantly higher than that of the convalescent phase and the healthy controls (F=65.805/50.418/155.381, P=0.000). A significant negative correlation was found between the serum levels of INF-gamma;, TNF-alpha; and IL-6 in acute phase with their initial visual acuity(r=-0.656, -0.592 and -0.653, Plt;0.01). There was also a positive correlation among the serum levels of INF-gamma;, TNF-alpha; and IL-6(r=0.340, 0.467 and 0.338, Plt;0.05). Conclusions There are high serum levels of INF-gamma;, TNF-alpha; and IL-6 in patients with acute uveitis, and the cytokines levels were decreased after the treatment. The results suggested that the INF-gamma;, TNF-alpha; and IL-6 involved in initiation and progression of uveitis. 

    Release date:2016-09-02 05:46 Export PDF Favorites Scan
  • An immunohistochemical study of Il-6,TNF-α in epiretinal membreanes.

    Purpose To investigate the expression of the interleukin-6(IL-6)and tumor necrosis factor alpha(TNF-alpha;) in epiretinal membranes(ERM) of eyes with proliferative vitreoretinopathy(PVR). Methods Nineteen epiretinal membranes were obtained form eyes undergoing vitrectomy for retinal detachment complicated with PVR and observed by immunohistochemical methods. Results Expression of IL-6 and TNF-alpha; were observed in 12 and 15 membranes respectively with positive staining mostly in extracellular matrix of epiretinal membranes.Only one membrane showed positive to IL-6 intracellularly,and expression for IL-6 and TNF-alpha; simultaneously in membranes. Conclusion The findings indicate that IL-6、and TNF-alpha;might be involved in the development of PVR. (Chin J Ocul Fundus Dis,1998,14:219-221)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • Inhibition of liposome-mediated recombinant plasmid expressing small interference RNA targeting hypoxia-induced factor-1α on retinal neovascularization in mice

    Objective To observe the inhibition of LipofectamineTM2000 (LF2000)mediated pSUPER recombinant plasmid expressing small interference RNA targeting hypoxia-induced factor (HIF)-1alpha;(pSUPERsiHIF-1alpha;) on retinal neovascularization in mice. Methods pSUPERsiHIF-1alpha; recombinant plasmid was created. Forty-eight (seven-day-old) C57BL/6J mice were randomly divided into a normal group, the control group, empty vector group and gene therapy group with 12 mice in each group. Mice in the normal group were kept in normal room air, while the other three groups retinal neovascularization was induced by hypoxia. The mice in control group were not treated. The mice in the vector group received intravitreous injection of pSUPER and LF2000 (1 mu;l), and the gene therapy group received pSUPERsiHIF-1alpha; and LF2000 (1 mu;l)one day before being returned to normal room air.Fluorescent angiography was used to assess the vascular pattern. The proliferative neovascular response was quantified by counting the nuclei of new vessels extending from the retina into the vitreous in cross-sections.HIF-lalpha;and vascular endothelial growth factor (VEGF) levels in retinas were measured by immune histochemical staining method and reverse transeriptase-polymerase chain reaction (RT-PCR). Results Fluorescent angiography showed radial branching pattern vessels in the normal group and distorted large vessels, obstructed capillaries, many neovascular tuffs, fluorescence leakage in the peripheral retina in the control group and vector group. The gene therapy group demonstrated a significant reduction in neovascular tufts and fluorescence leakage compared with the control group and the vector group. The number of vascular cell nuclei extending breaking through the internal limiting membrane(ILM) of control group and vector group increased significantly compared with normal group (F=5850.016,P<0.05), while obviously decreasing in the gene therapy group compared with control group (F=3012.469,P<0.05). Immunohistochemical staining showed the expression of HIF-1alpha; protein in nucleus and VEGF protein in cytoplasm. The expression of HIF-1alpha; protein in retina was negative, while VEGF protein was weakly positive in normal group. The expression of HIF-1alpha; and VEGF protein were both positive in control group and vector group, while weakly positive in gene therapy group. The Results of RT-PCR showed that the expression of HIF-1alpha; mRNA in retina was increased significantly in control group and vector group as compared with normal group (F=3102.326,P<0.05), while decreasing significantly in gene therapy group as compared with control group (F=3336.425,P<0.05). Conclusion Retinal neovascularization in the mice is significantly inhibited by intravitreal injection of LF2000-mediated recombinant plasmid pSUPERsiHIF-1alpha;.

    Release date:2016-09-02 05:22 Export PDF Favorites Scan
  • Influence of hypoxia-inducible factor-1α on the expression of neutrophil CD18 and leukocyte adhesion in diabetic rats

    Objective To observe the influence of the expression of CD18 on the neutrophile and the leukocyte adhesion to retinal vascular endothelium by hypoxia-inducible factor-1 alpha (HIF-1alpha;) in early diabetic retinopathy rats. Methods Male Sprague-Dawley rats received intraperitoneal injection of streptozotocin to induce diabetes model. 18 diabetic rats were divided into 3 groups randomly after 2 months of diabetes induction, including diabetic group (group B), HIF-1alpha; anti-sense oligonucleotides (ASODN) injection group (group C) and HIF-1alpha; sense oligonucleotides (SODN) injection group (group D), the age and weigh matched health rats were chosen as control group (group A), with 6 rats in each group. Then group A and B rats received 5% glucose solution caudalis veins injection, group C and group D rats received HIF-1alpha; ASODN and HIF-1alpha; SODN caudalis veins injection, respectively(025 mg/kg).The level of CD18 on the neutrophil isolated from the peripheral blood was measured by flow cytometry. Retinal leukostasis was quantified with acridine orange leukocyte fluorography. Results The percentage of CD18 positive neutrophil cell was(44.93plusmn;3.60)% in group B,(18.66plusmn;1.52)% in group A,(31.66plusmn;4.72)% in group C,(51.00plusmn;5.66)% in group D. Compared with each other groups,the differences are statistically significant (F=42.46, Plt;0.001). The number of positive staining cells of retinal leukocyte was (46.16plusmn;10.68)in group A,(133.83plusmn;20.43)in group B,(99.83plusmn;9.28)in group C,(121.33plusmn;10.23) in group C. Compared group B with group C,the number of positive staining cells raised about 2.89 times;compared group B with group C and D,the differences are statistically significant (P=0.12,95% confidence interval -3.69~28.69). Conclusions In vivo, HIF-1alpha; can decreased the expression of CD18 on neutrophils from diabetic ratsprime; peripheral blood and the collection of retinal leukostasis in the diabetic animals. HIF-1alpha; may serve as a therapeutic target for the treatment and/or prevention of early diabetic retinopathy.  (Chin J Ocul Fundus Dis,2008,24:268-271)

    Release date:2016-09-02 05:46 Export PDF Favorites Scan
  • Effect of Crocin on structure and the expression of tumor necrosis factor-α and interleukin-1β in rat retina after injury by ischemia-reperfusion

    ObjectiveTo observe the effect of Crocin on structure and the expression of tumor necrosis factor-alpha; (TNF-alpha;) and interleukin-1beta; (IL-1beta;) in rat retina after injury by ischemia-reperfusion. Methods A total of 80 Sprague-Dawley male rats at the age of 8 -10 weeks were divided into control group, model group, low-dose Crocin group and high-dose Crocin group, with 20 rats in each group. The rats of control group were not treated. The rats in model, low-dose Crocin and high-dose Crocin group were induced with normal saline by anterior chamber perfusion creating a retinal ischemia-reperfusion (RIR) model. The rats of the low-dose Crocin and highdose Crocin group received intraperitoneal injection with different doses of Crocin solution (5 mg/kg, or 50 mg/kg) 30 minutes prior to ischemic injury and one time per day after successful RIR. Optical microscopy was used to observe the retinal structure. Enzymelinked immunosorbent assay (ELISA) was used to measure the expression of TNF-alpha; and IL-1beta; 6, 12, 24 and 48 hours after RIR. ResultsThe retinal structure of control group was normal. Pathological changes were found in the RIR model and low-dose Crocin group, such as retinal edema, disorganized structure and loosely packed cells. The degree of pathological changes in lowdose Crocin group was less than the RIR model group. The retinal structure of high-dose Crocin group was similar to the control group. The expression of TNF-alpha; was the highest at 24 hours after modeling, while the expression of IL-1beta; was the highest at 12 and 48 hours after RIR modeling. Six, 12, 24 and 48 hours after RIR modeling, compared with the control group, the TNF-alpha; expression of model (t=5.42, 7.94, 9.32, 9.18;P<0.05 ), low-dose Crocin (t=3.94, 4.12, 4.98, 3.84;P<0.05) and high-dose Crocin group (t=2.13, 2.34, 2.96, 2.78;P>0.05) were increased. Compared with the RIR model group, the TNF-alpha; expression of low-dose Crocin (t=3.95, 4.56, 4.01, 5.12) and high-dose Crocin group (t=5.23, 7.65, 7.74, 7.63) was decreased. Compared with the control group, the IL-1beta; expression of model (t=7.23, 7.87, 7.15, 15.60), low-dose Crocin (t=5.65, 5.10, 5.54, 6.87;P<0.05) and high-dose Crocin group (t=4.38, 5.21, 4.56, 4.75) was increased (P<0.05). Compared with the model group, the IL-1beta; expression of low.dose Crocin group was decreased significantly 48 hours after RIR modeling (t=7.56,P<0.05); but it decreased significantly at each time point in high-dose Crocin group (t=6.94, 5.36, 6.05, 10.50;P<0.05). Conclusion Crocin can improve the retinal pathologic changes, while down-regulating TNF-alpha; and IL-1beta; expression in RIR rats.

    Release date:2016-09-02 05:22 Export PDF Favorites Scan
  • The expression of hypoxia inducible factor -1αin embryonic and postnatal rats′retinae

    Objective To investigate the expression of hypoxia inducible factor 1(HIF1alpha;) in ratsprime; retinae during the embryonic and earlier postnatal period. Methods The retinal expression patterns of HIF-1alpha; protein and mRNA of embryonic day 12 (E12), E16, E20, and postnatal day 1(P1) and P5 rats were determined by immunohistochemical staining and reverse transcriptionpolymerase chain reaction (RT-PCR). Results HIF-1alpha; protein was detected in the neural epithelial layer and the pigment epithelial layer at all those 5 timepoints, with higher expression in the ganglion cell layer and the inner plexiform layer, and seems limited to the ganglion cell layer when re tina became more mature. Embryonic rat retina had higher expression of HIF-1alpha; protein and mRNA than postnatal retina, the difference was significant (P<0.01). Conclusion The expression of HIF1alpha; in ratsprime;retina e differs from embryonic to earlier postnatal stages. 

    Release date:2016-09-02 05:42 Export PDF Favorites Scan
  • Study on Brain Functional Connectivity Using Resting State Electroencephalogram Based on Synchronization Likelihood in Alzheimer's Disease

    Alzheimer's disease (AD) is the most common type of dementia and a neurodegenerative disease with progressive cognitive dysfunction as the main feature. How to identify the early changes of cognitive dysfunction and give appropriate treatments is of great significance to delay the onset of dementia. Some other researches have shown that AD is associated with abnormal changes of brain networks. To study human brain functional connectivity characteristics in AD, 16 channels electroencephalogram (EEG) were recorded under resting and eyes-closed condition in 15 AD patients and 15 subjects in the control group. The synchronization likelihood of the full-band and alpha-band (8-13 Hz) data were evaluated, which resulted in the synchronization likelihood coefficient matrices. Considering a threshold T, the matrices were converted into binary graphs. Then the graphs of two groups were measured by topological parameters including the clustering coefficient and global efficiency. The results showed that the global efficiency of the network in full-band EEG was significantly smaller in AD group for the values of T=0.06 and T=0.07, but there was no statistically significant difference in the clustering coefficients between the two groups for the values of T (0.05-0.07). However, the clustering coefficient and global efficiency were significantly lower in AD patients at alpha-band for the same threshold range than those of subjects in the control group. It suggests that there may be decreases of the brain connectivity strength in AD patients at alpha-band of the resting-state EEG. This study provides a support for quantifying functional brain state of AD from the brain network perspective.

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  • Effects of cytokines on early growth response gene-1 in cultured human retinal pigment epithelial cells

    Objective To detect the effects of cytokines on the expression of early growth response gene-1 (Egr-1) in cultured human retinal pigment epithelial (RPE) cells. Methods Immunofluorescence staining, Western blotting and reverse transcription polymerase chain reaction (RT-PCR) were used to detect and quantitatively analyze the expression of Egr-1 protein and mRNA in cultured human RPE cells which were exposed to stimulants, including 20 mu;g/ml lipopolysaccharide (LPS), 40 ng/ml tumor necrosis factor (TNF)-alpha;, 10 U/ml interferon (IFN)gamma;, 30% supernatant of monocyte/macrophage strain (THP1 cells) and the vitreous humor from healthy human eyeballs, for 0, 10, 20, 30, 40 and 60 minutes, respectively. Results The RPE cells stimulated for 0 minute revealed faint green fluorescence of Egr-1 in the cytoplasm. With exposure to the stimulants, the expressionof Egr-1 increased obviously and b green fluorescence was found in cytoplasm in some nuclei of RPE cells. Compared with the untreated RPE cells, after stimulated by 20 mu;g/ml LPS, 40 ng/ml TNFalpha;, 10 U/ml IFNgamma;, 30% supernatant of THP-1 cells and the vitreous humor, the approximate ultimate amplitudes of Egr-1 mRNA enhanced 1.9, 1.3, 14, 1.2, and 1.4 times, respectively; the greatest amplitudes of Egr-1 protein increased 3.4, 1.2, 1.7, 32, and 1.3 times, respectively. Conclusion LPS, TNF-alpha;, IFN-gamma;, supernatant of THP-1 cells and the vitreous humor can upregulate the expression of Egr-1 mRNA and protein in cultured human RPE cells, and induce its nuclear transposition, which suggests the activation of Egr-1.

    Release date:2016-09-02 05:48 Export PDF Favorites Scan
  • Inhibition of expression of vascular endothelial growth factor by interfering RNA targeting hypoxia inducible factor1α and vascular endothelial growth factor in human vascular endothelial cells

    Objective To investigate the effect of small interfering RNA(siRNA) targeting hypoxia inducible factor1alpha; (HIF1alpha;) and vascular endothelial growth factor (VEGF) on expression of VEGF in human vascular endothelial cells. Methods HIF-1alpha; siRNA recombinant plasmid was constructed. Human vascular ndothelial cells were cultured in vitro and divided into normoxia group (20% O2) and hypoxia group (1% O2). Hypoxia group was then divided into control group, vector group, HIF-1alpha; group (HIF-1alpha; siRNA), VEGF group ( VEGF165  siRNA) and cotransfection group (HIF-1alpha; siRNA+VEGF165 siRNA). LipofectamineTM 2000 (LF2000) mediated vector plasmid was transfected to cells in each group except the control group. The expression of HIF-1alpha; siRNA and VEGF165 siRNA recombinant plasmid were identified by reverse transcriptasepolymerase chain reaction (RT-PCR). The expression of VEGF mRNA and protein were detected by RTPCR and immunocytochemical method. Results The expression of HIF-1alpha; siRNA and VEGF165 si RNA recombinant plasmid were detected 24 hours after transfected. The expression of VEGF mRNA and protein was faint in the normoxia group, but increased obviously in hypoxia group. The expression of VEGF mRNA and protein in the HIF1alpha;, VEGF and cotransfection groups were lower than which in the control group. Cotransfection group showed the highest inhibitory effect. Conclusion HIF-1alpha; and VEGF165 siRNA can effectively inhibit the expression of VEGF in human vascular endothelial cells.

    Release date:2016-09-02 05:48 Export PDF Favorites Scan
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