Effect of 5-HT1A receptors in the hippocampal DG on active avoidance learning in rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of serotonin (5-HTIA) receptors in the hippocampal dentate gyrus (DG) on active avoidance learning in rats.</p><p><b>METHODS</b>Totally 36 SD rats were randomly divided into control group, antagonist group and agonist group(n = 12). Active avoidance learning ability of rats was assessed by the shuttle box. The extracellular concentrations of 5-HT in the DG during active avoidance conditioned reflex were measured by microdialysis and high performance liquid chromatography (HPLC) techniques. Then the antagonist (WAY-100635) or agonist (8-OH-DPAT) of the 5-HT1A receptors were microinjected into the DG region, and the active avoidance learning was measured.</p><p><b>RESULTS</b>(1) During the active avoidance learning, the concentration of 5-HT in the hippocampal DG was significantly increased in the extinction but not establishment in the conditioned reflex, which reached 164.90% ± 26.07% (P <0.05) of basal level. (2) The microinjection of WAY-100635 (an antagonist of 5-HT1A receptor) into the DG did not significantly affect the active avoidance learning. (3) The microinjection of 8-OH-DPAT(an agonist of 5-HT1A receptor) into the DG significantly facilitated the establishment process and inhibited the extinction process during active avoidance conditioned reflex.</p><p><b>CONCLUSION</b>The data suggest that activation of 5-HT1A receptors in hipocampal DG may facilitate active avoidance learning and memory in rats.</p>

Roles of Rho/Rock signaling pathway in silica-induced epithelial-mesenchymal transition in human bronchial epithelial cells / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the roles of Rho/Rock signaling pathway in silica-induced Epithelial-mesenchymal transition (EMT) in human bronchial epithelial cells (BEC) in vitro.</p><p><b>METHODS</b>Human BEC were incubated with silica with various concentrations for indicated times. Cell viability was assayed by MTT test. Morphologic Changes were observed by microscope. Mesenchymal marker α-smooth muscle actin (α-SMA), vimentin (Vim), and epithelial marker E-cadherin (E-cad) were analyzed by Western Blot. The pull-down assay was used to measure Rho activity. In the prevention experiments, the specific inhibitor for Rho effector ROCK (Y27632) was used to inhibit the activity of Rho.</p><p><b>RESULTS</b>Human BEC stimulated with silica were converted from a "cobblestone" epithelial structure into an elongated fibroblast-like shape structure. Incubation of human BEC with silica induced de novo expression of α-SMA and Vim, and loss of E-cad. Also, silica treatment resulted in Rho activation in human BEC. Y27632 up-regulated the E-cad expression but attenuated α-SMA and Vim expression in silica-stimulated cells.</p><p><b>CONCLUSION</b>The activation of Rho/ROCK signaling pathways is most likely involved in Silica-induced EMT in human bronchial epithelial cells.</p>

The influence of SiO2 on epithelial-mesenchymal transition (EMT) in human bronchial epithelial cells / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate SiO2-induced EMT in human bronchial epithelial cells HBE in vitro.</p><p><b>METHODS</b>HBE cells were cultured and then stimulated with indicated doses of SiO2 (0, 50, 100, 200, 300 µg/ml). The morphological changes were observed by microscope. In addition, Western blot was per-formed to detect the expression of E-cad, α-SMA and Vim. The changes of migration ability were examined by wound-healing assay in vitro.</p><p><b>RESULTS</b>(1) After exposure to SiO2, HBE cells lost contact with their neighbor and displayed a spindle-shape, fibroblast-like morphology. (2) Compared with the control, the E-cad (300 µg/ml group) expression downregulated 2.98 fold (P < 0.05), and the Vim (300 µg/ml group) and α-SMA (200 µg/ml group) expression upregulated 4.46 fold and 3.55 fold (P < 0.05). There were significant differences between 100, 200, 300 µg/ml groups and the control group (P < 0.05). (3) In the test group, the percentage of wound-healing areas/wound areas were larger than those in control group (P < 0.05).</p><p><b>CONCLUSIONS</b>SiO2 could induce EMT in human bronchial epithelial cells.</p>

Effect of chronic iron overload on atherosclerosis lesion in apolipoprotein E knockout mice / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of chronic iron overload on the lesion of atherosclerosis (AS) in apolipoprotein (apo) E knockout mice.@*METHODS@#Twenty-four ApoE knockout mice were randomly divided into ApoE knockout group (0.1 mL saline for 4 weeks) and iron overload group (10 mg iron dextran for 4 weeks). The levels of serum iron (SI), total iron binding capacity, contents of malondialdehyde (MDA), and activity of superoxide dismutase (SOD) in the liver were measured. Iron deposition in the liver and heart was determined, and atherosclerotic plaque areas of the sinus aortae were analyzed.@*RESULTS@#In the iron overload group, the levels of SI increased by 377.86%, the saturation of transferrin increased by 121.98% and the levels of iron in the liver increased by 2,548.15% (P<0.01). The contents of MDA in the liver increased by 32.51% (P<0.01), and the activity of SOD in the liver decreased by 17.2% in the ApoE knockout group (P<0.05). The level of MDA in the liver increased by 411.15%, and the activity of SOD in the liver decreased by 46.84% in the iron overload group (P<0.01). There was a significant deposition of iron in the liver and heart of mice, and the areas of atherosclerotic plaque of sinus aortae increased markedly in the iron overload group.@*CONCLUSION@#Chronic iron overload may promote the development of AS lesion in the ApoE knockout mice, in which the increased oxidative stress and lipid oxidation may involve.

Effect of Twist gene on the migration and invasion of gastric carcinoma cells / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of Twist gene on the migration and invasion of human gastric carcinoma cells.@*METHODS@#MKN28 cells, a human gastric carcinoma cell line, were transfected with PcDNA3.1-Twist plasmid by lipofectamine transfecting technique. The transfected cells were selected with geneticin. Expressions of Twist,ecadherin and vimentin protein were detected by Western blot in cells transfected Twist gene. Matrigel invision chambers were performed to analyse the cell migration and invasion.@*RESULTS@#MKN28 cells transfected with PcDNA3.1-Twist plasmid showed stronger intracellular expression of Twist protein than MKN28 cells transfected with PcDNA3.1 and MKN28 cells without transfection. The expression of ecadherin protein in MKN28 cells transfected with PcDNA3.1-Twist plasmid was significantly decreased compared with that in MKN28 cells transfected with PcDNA3.1 and MKN28 cells without the transfection. However, The expression of vimentin protein in MKN28 cells transfected with PcDNA3.1-Twist plasmid was significantly increased compared with that in MKN28 cells transfected with PcDNA3.1 and MKN28 cells without transfection. The migration and invasion ability of Twist+ - MKN28 cells were stronger than that of MKN28 cells transfected with PcDNA3.1 and MKN28 cells without transfection.@*CONCLUSION@#Twist gene may promote the migration and invasion ability of gastric carcinoma cells through epithelial mesenchymal transition.

Role of activator protein-1 in pathogenesis of silicosis: an in-vitro study / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the role of activator protein-1 (AP-1) in the up-regulation expression of tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1(TGF-beta(1)) in silica-stimulated macrophage cells (RAW264.7).</p><p><b>METHODS</b>RAW264.7 cells were treated with AP-1 inhibitor Curcumin. The expression of c-jun and c-fos in nuclear protein was detected by western blotting. The level of TNF-alpha and TGF-beta(1) protein in the cell supernatant was measured using enzyme-linked immunoadsorbent assay (ELISA). Meanwhile the expression of TNF-alpha and TGF-beta(1) mRNA was also monitored by reverse transcriptase-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The nucleoprotein expression of c-jun and c-fos in 10 and 20 micromol/L Curcumin prevention group (1.150 +/- 0.020, 1.010 +/- 0.108, 80.430 +/- 0.023, 0.256 +/- 0.015) were lower than those in silica-stimulated group (1.550 +/- 0.029, 0.860 +/- 0.036) (P < 0.01). In 20 micromol/L Curcumin prevention group and silica stimulated group, the expression of TNF-alpha protein were 23.58 +/- 45.78 and 32.12 +/- 5.34, and the expression of TGF-beta(1) protein were 1582.18 +/- 437.52 and 55.60 +/- 5.51 (P < 0.05 =; the expression of TNF-alpha, TGF-beta(1) mRNA were 0.74 +/- 0.01, 0.22 +/- 0.04 and 2.27 +/- 0.33, 2.96 +/- 0.15 (P < 0.05 =.</p><p><b>CONCLUSION</b>The expression of TNF-alpha, TGF-beta(1) mRNA and proteins is associated with activation of AP-1 in silica-stimulated macrophage cells.</p>

Effect of antagonism of glutamate receptors in the PVN region on baroreflex in conscious rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the possible involvement of glutamate(Glu) in the paraventricular nucleus (PVN) in the central regulation of baroreflex.</p><p><b>METHODS</b>The baroreflex was induced by intravenous injection of phenylephrine in conscious rats, and the extracellular concentration of Glu in the PVN region was measured by microdialysis and high performance liquid chromatography (HPLC) techniques. To determine whether the observed Glu release was involved in the baroreflex, NMDA and non-NMDA receptor antagonists, MK-801 and CNQX, were perfused in the PVN region during baroreflex.</p><p><b>RESULTS</b>During baroreflex, the Glu concentration in the PVN region immediately increased to 384.82% +/- 91.77% of basal level (P < 0.01). (2) During baroreflex, direct perfusion of MK-801 and CNQX in the PVN were attenuated the increase of blood pressure and enhanced the decrease of HR (P < 0.01),resulting a significant increase in baroreflex sensitivity (P < 0.01).</p><p><b>CONCLUSION</b>Glutamate in PVN is involved in central regulation of baroreflex, which may inhibit baroreflex via ionothopic glutamate receptors.</p>

Development and application of universal and specific diagnostic reagents for human respiratory adenovirus / 中国地方病学杂志

Objective To establish a specific,sensitive,simple human respiratory adenovirus detection method to put a good experimental foundation for developing universal and specific diagnostic reagents of human respiratory adenovirus.Methods The nucleotide sequences of 10 serotype of human respiratory adenovirus were obtained from GenBank.Highly consewed five pairs of universal and specific adenovirus primers were designed on the evaluation of multiple sequence alignment of the 10 full genomic sequences with the software DNAMAN 5.2.2,Gene Runner 3.05,BLAST,and to ensure that the polymerase chain reaction(PCR)products were type-specific.NP-40 sample lytic method was employed to prepare the template.The effectiveness,specificity and sensitivity of primers were evaluated.And PCR was carried out to test 64 samples of throat swabs of acute respiratory infection children.The positive PCR products were sequenced directly to identify the adenovirus serotypes.The positive specimens was inoculated on HeLa cells to observe cytopathie effect(CPE)under light microscope,and virus morphology were observed under electron microscope.Results BLAST results indicated that the five pairs of primers were specific adenovirus primers with low homology to the others.The primers were identified as PCR positive fragments obtained by using five pairs of primers to amplify the human adenovirus type 3 DNA,which did not react to the respiratory syncytial virus and Coxsackie virus.the effectiveness and specificity of the primer were thus indicated.PCR sensitive results showed 10-5 dilutin of adenovirus culture and DNA sample could be deteeted which meant the method was sensitive and stable.Two PCR positive specimens were detected in 64 clinical samples.the positive rate was 3.13%(2/64).Using the two PCR positive specimens to inoculate the HeLa cells,the typical adenovirus CPEs of rounded and aggregated,detatched cells were observed under light microscope.And a large number of adenovirus typical particles with characteristic lattice arrangement were observed in the infected cells under electron microscope.PCR product sequencing results showed that these two isolated adenoviruses were typed in human adenovims group B.Conclusions Universal and specific adenovirus PCR primers with the serotype specificity of the PCR products were designed successfully.The PCR primers was sensitive and specific and could be routinely applied in clinical adenovirus diagnosis for respiratory specimens.

Expression and significance of Notch1, Jagged1 and VEGF in human non-small cell lung cancer / 中南大学学报(医学版)

OBJECTIVE@#To determine the expressions of Notch1, Jagged1 and vascular endothelial growth factor (VEGF) in human non-small cell lung cancer (NSCLC) and to explore its clinical pathological significance.@*METHODS@#Immunohistochemical SP method was used to detect the expressions of Notch1, Jagged1 and VEGF in 65 patients with NSCLC and 15 normal epithelial tissues of the lung, and the relationship between them and clinic-pathological parameters were analyzed.@*RESULTS@#The positive rates of Notch1, Jagged1 and VEGF in NSCLC were 81.5%, 83.1% and 93.8%, respectively, higher than those in normal epithelial tissues of the lung (P<0.05). The positive expression levels of Notch1 and VEGF were closely associated with the tumor stage and the lymph node metastasis (P<0.05). The positive expression levels of Jagged1 was positively correlated with the pathological type and lymph node metastasis. There was a positive correlation between Notch1, Jagged1 and VEGF.@*CONCLUSION@#Notch1, Jagged1 and VEGF protein may play an important role in the pathway of carcinogenesis and progression of NSCLC. The up-regulation of Notch1, Jagged1 and VEGF protein expression probably predict NSCLC carrying relatively strong permeation and metastasis.

Changes of amino acid concentrations in the rat medial vestibular nucleus following unilateral labyrinthectomy / 生理学报

To understand the neurochemical mechanisms underlying the vestibular compensation, we determined the levels of amino acids such as aspartate, glutamate, glutamine, glycine, taurine, alanine in the medial vestibular nucleus (MVN) following unilateral labyrinthectomy (UL), by using in vivo brain microdialysis and high-performance liquid chromatography technique. Rats were pretreated by infusing 2% lidocaine 1.2 mL or 10 mg arsanilic acid into the tympanic cavity to obstruct uni-periphery vestibular organ, and then the levels of amino acids were determined in MVN of normal control and ipsilateral or contralateral lesional (ipsi-/contra-lesional) rats. In the control experiment, the levels of aspartate, glutamate, glutamine, glycine, taurine, and alanine were (6.15 +/- 0.59), (18.13 +/- 1.21), (33.73 +/- 1.67), (9.26 +/- 0.65), (9.56 +/- 0.77) and (10.07 +/- 0.83) pmol/8 muL sample, respectively. The concentrations of aspartate and glutamate decreased, while the concentration of taurine increased in the ipsi-lesional MVN of rats 10 min after infusing 2% lidocaine into middle ear to obstruct uni-periphery vestibular organ. Whereas the concentration of glutamate increased, the concentrations of glycine and alanine decreased in the contra-lesional MVN, accompanied by imbalances of glutamate, glycine and alanine in the bilateral nuclei. In contrast, the levels of glutamate and alanine decreased, the level of glutamine increased in the ipsi-lesional MVN, and the level of glutamate decreased in the contra-lesional MVN of rats 2 weeks after infusing 10 mg arsanilic acid into the tympanic cavity to obstruct uni-periphery vestibular organ. Furthermore, the level of glutamine in the ipsi-lesional MVN was obviously higher than that in the contra-lesional MVN. These results demonstrate that an imbalance of different amino acids appeared in bilateral MVN after UL, and this imbalance decreased after the development of vestibular compensation. Whereas the imbalance of glutamine release in bilateral nuclei appeared after vestibular compensation.

p38/ERK signal pathways regulating the expression of type I collagen and activity of MMP-2 in TGF-beta1-stimulated HLF-02 cells / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the role of TGF-beta(1)/MAPK signaling pathways in the expression of type I collagen and activity of MMP-2, 9 in human lung fibroblasts.</p><p><b>METHODS</b>Human lung fibroblasts cell line (HLF-02) was cultured and and then stimulated with 10 ng/ml TGF-beta(1) for different time; SB203580 or PD98059 was added into culture medium to block p38 or ERK kinase pathway before incubated with TGF-beta(1); the expression of type I collagen was detected by Western blotting and RT-PCR; zymogram analysis was used to analyze the activity of MMP-2 and MMP-9.</p><p><b>RESULTS</b>(1) In the process of stimulation by TGF-beta(1), the type I collagen mRNA level of 24 h, 48 h and 72 h group was: 1.33 +/- 0.07, 2.46 +/- 0.09 and 2.39 +/- 0.08 respectively; and the type I collagen protein level of 24 h, 48 h and 72 h group was: 114.89 +/- 8.95, 208.16 +/- 6.75 and 211.46 +/- 8.05 respectively; and the activity of MMP-2 of 24 h, 48 h and 72 h group was: 190.33 +/- 5.86, 214.33 +/- 8.39 and 212.67 +/- 11.59 respectively. (2) SB203580 significantly inhibited the TGF-beta(1)-induced expression of type I collagen mRNA, protein and MMP-2 activity (inhibition ratio: 51%, 24% and 20%); (3) PD98059 also significantly attenuated the TGF-beta(1)-induced expression of type I collagen mRNA, protein and MMP-2 activity (inhibition ratio: 42%, 13% and 16%).</p><p><b>CONCLUSION</b>TGF-beta(1) is capable of inducing the expression of type I collagen mRNA and protein and up-regulating MMP-2 activity in HLF-02 cells. p38 and ERK kinase signaling pathways play important role in regulation and control for this process.</p>

Effects of silicon dioxide on expression of alpha-smooth muscle actin in human lung fibroblasts / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of SiO(2) on the expression of alpha-smooth muscle actin (alpha-SMA) in human lung fibroblasts in vitro and vivo.</p><p><b>METHODS</b>The experimental group comprised 32 rats while 32 rats were included in the control. In vivo, the expression of alpha-SMA in lung tissues of rats exposed to SiO(2), the supernate of RAW264.7 cells, SiO(2) and the growth factor beta(1) (TGF-beta(1)) were investigated, respectively.</p><p><b>RESULTS</b>(1) alpha-SMA positive myofibroblasts appeared in the lung tissues of the 28th day groups exposed to SiO(2). (2) The expression of alpha-SMA in HLF-02 cells was unregulated by TGF-beta(1) and supernate of RAW264.7 cells exposed to SiO(2). (3) The expression of alpha-SMA in HLF-02 cells was not induced by SiO(2).</p><p><b>CONCLUSION</b>Myofibroblasts related to silicosis, and the appearance of myofibroblasts (in vitro) are independent on direct stimulation by SiO(2), but related to the mediator (TGF-beta(1)) secreted by SiO(2) stimulated macrophages.</p>

Expression of survivin and proliferating cell nuclear antigen in human non-small cell lung cancer / 中南大学学报(医学版)

OBJECTIVE@#To determine the expressions of survivin and proliferating cell nuclear antigen (PCNA)in non-small cell lung cancer (NSCLC) and to explore its clinical pathological significance.@*METHODS@#Immunohistochemical SP method was used to detect the expressions of survivin and PCNA in 43 patients with NSCLC and 15 normal epithelial tissues of the lung. PCNA labeling proliferative index was assessed. Forty-three patients with NSCLC were followed up for more than 5 years.@*RESULTS@#The positive expression of survivin in NSCLC (79.1%) was significantly higher than that in normal epithelial tissues of the lung (P 0.05). The mean proliferative index of PCNA in NSCLC was much higher than that in normal epithelial tissues of the lung (P < 0.01). A positive correlation was present between the proliferative index and the tumor size, lymph node metastase, and clinical stage (P <0.01), while a negative correlation between the proliferative index and survival time (P <0.01). There was no correlation between proliferative index and age, sex, site, histological type and grade. The proliferative index was larger in patients with moderate or strong positive survivin expression than that in patients with negative or weak survivin expression (P < 0.05).@*CONCLUSION@#Over expression of survivin and PCNA is closely correlated to the progression and prognosis of patients with NSCLC, which is helpful to evaluate the progression of cancer and to predict the prognosis of NSCLC. The up-regulation of survivin expression and its close relationship with the cell proliferation in NSCLC suggest that survivin may play an important role in the carcinogenesis and development of lung cancer.

Effect of microinjection of atrial natriuretic peptide into the paraventricular nucleus on baroreflex sensitivity in conscious rats / 生理学报

The role of atrial natriuretic peptide (ANP) in the central regulation of the circulation is known to be a neurotransmitter or a neuromodulator, but its actions on baroreceptor reflex function are not fully resolved. The present study examined the role of ANP (6, 60 ng/0.2 microl) by direct microinjection into the hypothalamic paraventricular nucleus (PVN) in conscious rats. OPC-21268 (0.45 microg/3 microl), an antagonist of the V(1) receptor, was microinjected into the lateral ventricle to examine whether the effect of ANP on baroreflex sensitivity is mediated by vasopressin (VP). ANP significantly increased the baroreflex sensitivity, and OPC-21268 attenuated the increase of baroreflex sensitivity induced by ANP. Intravenous injections of ANP (60 ng/0.04 ml) did not affect baroreflex sensitivity. These results suggest that ANP in the PVN may produce a facilitative effect on baroreflex, and the effect may be via, at least in part, the central vasopressin.

Sudy on the activation of early growth response factor-1 by silica dioxide and its signal pathway / 中华病理学杂志

<p><b>OBJECTIVE</b>To discuss the role of early growth response factor (Egr)-1 and it's upstream signaling pathway in the development of silicosis.</p><p><b>METHODS</b>The expression and localization of Egr-1 were analyzed by immunofluorescence and in-situ hybridization. The activity of Egr-1 was observed in treated cells by using a reporter plasmid and EMSA, the activity of ERK1/2 in RAW264.7 incubated with SiO(2) by using a kinase assay, and further by using a kinase inhibitor assay to investigate the role of upstream kinase in the signal pathway of the activation of Egr-1.</p><p><b>RESULTS</b>The obvious increase of expression and transcription of Egr-1 was observed shortly after being treated by silica and its activity increased abruptly. There was an increase of the activity of ERK1/2 in RAW264.7 cells treated, which reached a peak at 30 minutes. The expression and transcription of Egr-1 decreased maniferstly after using kinase inhibitors.</p><p><b>CONCLUSION</b>Egr-1 expression can be induced by silica dioxide in RAW264.7 cells, and the ERK1/2, p38 kinases may take part in this process which suggest the pathway of SiO(2), ERK1/2, p38 and Egr-1 may play an important role in the development of silicosis.</p>

Expression of early growth response gene-1 in macrophages stimulated by silicon dioxide / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the expression and localization of early growth response gene-1 (Egr-1) in macrophages after stimulation by silicon dioxide in vivo and in vitro and to discuss the role of Egr-1 in the development of silicosis.</p><p><b>METHODS</b>The expression of Egr-1 in animal model of silicosis was analyzed by using immunohistochemistry. Western-blot, immunofluorescence and RT-PCR analysis were used to detect the expression and localization of Egr-1 protein and the dynamic changes of Egr-1 mRNA in cultured macrophages RAW264.7, after stimulation by silicon dioxide.</p><p><b>RESULTS</b>In animal model with induced silicosis, there was an increased expression of Egr-1 in pulmonary macrophages. The expression levels peaked at the 14th day. In vitro, the transcription of Egr-1 increased in RAW264.7 macrophages during 15 to 240 minutes after the administration of silicon dioxide. The response peaked at 15 minutes and diminished to a minimal level at 480 minutes. Nuclear translocation was most apparent at 60 minutes, lasted till 120 minutes and diminished gradually. During the period from 60 to 120 minutes, the expression of Egr-1 protein also reached a peak.</p><p><b>CONCLUSIONS</b>Silicon dioxide can activate the nuclear transcription factor Egr-1 in vivo and in vitro in macrophages. Egr-1 may thus play an important pathogenetic role in the development of silicosis.</p>