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871.
Rainbow trout, Oncorhynchus mykiss, were exposed to 48h of environmental hypoxia (water partial pressure of oxygen = 8.0 kPa) at either 5 or 15°C. Blood was sampled during hypoxia via a dorsal aorta cannula to measure arterial blood partial pressure of oxygen and plasma catecholamine concentrations. After 48h, the number (Bmax) and dissociation constant (Kd) of red blood cell surface -adrenoceptors were determined using a radioligand-displacement binding assay. At 5°C, plasma catecholamine levels were elevated at 24h whereas at 15°C, levels were elevated at 48h. At either temperature, following 48h of hypoxia, there was no change in Bmax or Kd of red blood cell surface -adrenoceptors, compared to normoxic control fish. This study demonstrates that chronic exposure to moderate hypoxia does not affect the number or affinity of cell surface -adrenoceptors on trout red blood cells. 相似文献
872.
873.
《中国兽医学报》2014,(6):973-976
为了探讨归参汤(GST)对免疫抑制小鼠血清中IL-2、TNF-α和脾细胞Th1/Th2细胞因子的影响。本试验采用环磷酰胺制造免疫抑制模型,利用双抗夹心ELISA法,观察归参汤对小鼠血清中IL-2、TNF-α的影响;RT-PCR法观察归参汤对小鼠脾细胞中INF-γ、IL-4、T-bet和GATA-3的mRNA表达的影响。结果显示:归参汤高剂量组可以显著增加免疫抑制小鼠血清中IL-2、TNF-α的含量(P<0.01),提高INF-γ的表达(P<0.05),降低IL-4的含量(P<0.05),升高T-bet(P<0.05),降低GATA-3的表达(P<0.05)。归参汤的免疫增强作用与升高血清中IL-2、TNF-α有关,且升高INF-γ/IL-4纠正免疫抑制小鼠Thl/Th2细胞因子的比例紊乱,其机制可能部分归因于对T-bet和GATA-3的mRNA表达的影响。 相似文献
874.
875.
AIM:To investigate the relationship of microRNA-7 (miRNA-7) over-expression and epidermal growth factor receptor (EGFR)/phosphatidylinositol kinase-3 (PI3K)/protein kinase B (PKB, also called Akt) pathway in human nasopharyngeal carcinoma 5-8F cells. METHODS:The 5-8F cells were transfected with miRNA-7 mimics (carrying by Lipofectamine 2000). The expression of miRNA-7 was detected by real-time PCR. The cell proliferation was analyzed by CCK-8 assay. The cell colony-forming capability was determined by cell colony formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was examined by real-time PCR and Western blotting. RESULTS:The expression level of miRNA-7 was significantly increased in 5-8F cells compared with negative control (NC) group and control group (P<0.01). The proliferation of NPC 5-8F cells was decreased extremely after tansfected with the miRNA-7 mimics (P<0.01), so did the result of the cell colony-formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was significantly down-regulated compared with NC group and control group (P<0.01). CONCLUSION: Over-expression of miRNA-7 significantly inhibits the proliferation and colony-forming ability of nasopharyngeal carcinoma 5-8F cells by down-regulation of EGFR/PI3K/Akt pathway. 相似文献
876.
AIM:To investigate the inhibitory effects of resveratrol on chondrosarcoma and the relation with mitochondrial and PI3K/Akt pathways. METHODS:Chondrosarcoma SW1353 cells were treated with resveratrol at concentrations of 25, 50 and 100 μmol/L for the time intervals of 24 h, 48 h and 72 h. The viability and apoptosis of the SW1353 cells in the presence or absence of resveratrol were analyzed by CCK8 assay and Hoechst 33258 staining, respectively. The protein levels of Bcl-2, Bax, activated caspase-3, Akt and p-Akt were detected by Western blotting. The cell migration ability was determined by wound scratch assay. RESULTS:Exposure of the cells to resveratrol resulted in a decrease in the cell viability in a dose- and time-dependent manner (P<0.05). visible nuclei with apoptotic characteristics in resveratrol group were observed. The protein levels of activated caspase-3 and Bax were increased, and Bcl-2 and p-Akt were decreased compared with control group. The total Akt were not significantly changed. Resveratrol also significantly reduced the migration of tumor cells. CONCLUSION:Resveratrol induces apoptosis of chondrosarcoma, which plays a role of part through mitochondrial and PI3K/Akt signaling pathways. 相似文献
877.
AIM:To investigate the influence of high-mobility group box 1 (HMGB1) on the proliferation of neural stem cells in peri-infarction cortex of focal cerebral ischemia/reperfusion model rats. METHODS:Male SD rats (n=48) were randomly divided into sham group, ischemia/reperfusion (I/R) group, RNA interference group and negative interference group. The rat middle cerebral artery was blocked to establish focal cerebral I/R model (ischemia for 1 h and reperfusion for 7 d). Lentivirus vector of HMGB1 shRNA was used to suppress the HMGB1 protein expression in the rat brain. The effect of RNA interference was evaluated by the methods of double-immunofluorescence labeling of HMGB1/GFAP and Western blotting. The proliferation of neural stem cells in the peri-infarction cortex was assessed by double labeling of BrdU/nestin. RESULTS:The protein expression of HMGB1 in I/R group was much higher than those in sham group (P<0.05). RNA interference effectively inhibited the HMGB1 expression (P<0.05). Double labeled BrdU/nestin positive cells in I/R group were more than that in sham group (P<0.05). The double labeled BrdU/nestin positive cells were significantly decreased in RNA interference group (P<0.05). CONCLUSION:Focal cerebral ischemia/reperfusion injury promotes the proliferation of neural stem cells in peri-infarction cortex by increasing HMGB1 protein level. 相似文献
878.
Hong-tao Chang Xiu-yuan He Yu-Feng Liu Lu Chen Quan-hai Guo Qiu-ying Yu Jun Zhao Xin-wei Wang Xia Yang Chuan-qing Wang 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):399-407
A recombinant replication-defective adenovirus expressing the major epitopes of porcine circovirus-2 (PCV-2) capsid protein (rAd/Cap/518) was previously constructed and shown to induce mucosal immunity in mice following intranasal delivery. In the present study, immune responses induced by intranasal immunization with a combination of rAd/Cap/518 and cytosine-phosphate-guanosine oligodeoxynucleotides (CpG ODN) were evaluated in mice. The levels of PCV-2-specific IgG in serum and IgA in saliva, lung, and intestinal fluids were significantly higher in the group immunized with rAd/Cap/518 and CpG ODN than animals immunized with rAd/Cap/518 alone. The frequencies of IL-2-secreting CD4+ T cells and IFN-γ-producing CD8+ T cells were significantly higher in the combined immunization group than mice immunized with rAd/Cap/518 alone. The frequencies of CD3+, CD3+CD4+CD8-, and CD3+CD4-CD8+ T cells in the combined immunization group were similar to that treated with CpG ODN alone, but significantly higher than mice that did not receive CpG ODN. PCV-2 load after challenge in the combined immunization group was significantly lower than that in the phosphate-buffered saline placebo group and approximately 7-fold lower in the group treated with CpG ODN alone. These results indicate that rAd/Cap/518 combined with CpG ODN can enhance systemic and local mucosal immunity in mice, and represent a promising synergetic mucosal vaccine against PCV-2. 相似文献
879.
Zhiqiang Huang Meng Yu Shuang Tong Kun Jia Rongchang Liu Heng Wang Shoujun Li Zhangyong Ning 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(2):173-177
Activation of the innate immune system requires recognition of pathogen-associated molecular patterns, such as NOD-like receptors. The NOD-like receptor protein 3 (NLRP3) inflammasome is involved in induction of the pro-inflammatory cytokine, IL-1β, and subsequent inflammatory responses. NLRP3 inflammasome plays important roles in the inflammatory and innate immune responses associated with autoimmune/inflammatory syndrome. However, analysis of the tissue distribution and expression profiles in BALB/c mice is still incomplete. In this study, we investigated the tissue distribution and expression pattern of NLRP3 in BALB/c mice to further elucidate its function in innate immunity in this commonly used laboratory animal model. NLRP3 mRNA expression levels and tissue distribution of the protein were investigated by real-time quantitative PCR and immunohistochemical analyses, respectively. NLRP3 mRNA expression was higher in the kidney and inguinal lymph nodes than in other tissues. Cytoplasmic expression of NLRP3 was detected in the epithelial reticular cells of the spleen and thymus, lymphocytes in the inguinal lymph nodes, cardiac muscle cells, cerebral cortex neurons, alveolar macrophages, renal tubule cells and liver sinusoidal endothelial cells. The results of this study will assist investigators in interpreting site-specific functions and roles of NLRP3 in inflammatory responses. 相似文献
880.
《Journal of Veterinary Cardiology》2014,16(1):45-50
Difficulty was encountered with the insertion of a right atrial pacing lead via the left jugular vein during lead and pacemaker implantation in a clinically normal goat as part of an ongoing rapid atrial pacing – induced atrial fibrillation research project. Fluoroscopic visualization of an abnormal lead advancement path prompted angiographic assessment which revealed a persistent left cranial vena cava (PLCVC) and prominent coronary sinus communicating with the right atrium. Angiography facilitated successful advancement and securing of the pacing lead into the right side of the interatrial septum. Cardiac magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) allowed further characterization of this rare venous anomaly. Even though PLCVC has been reported once in a goat, to the authors' knowledge this is the first report to include MRI/MRA characterization of PLCVC and prominent coronary sinus with successful cardiac pacemaker implantation using the PLCVC. 相似文献