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991.
Juan Liu Guo-en Yao Hua-dong Zhou Xiao-jiang Jiang Qiao Chen 《Cell biochemistry and biophysics》2013,65(2):275-279
Hemodynamic instability is a common condition during extra-cranial carotid angioplasty and stenting (CAS). We evaluated the safety and efficacy of prophylactic placement of temporary cardiac pacemaker during extra-cranial CAS for the prevention of hemodynamic instability. For this, forty-seven carotid artery stents were deployed in 41 high-risk patients. Temporary transvenous cardiac pacemakers were inserted before CAS procedure. The pacers were set to capture a heart rate <60 bpm. Clinical symptoms, blood pressure, heart rate, and pacing activation were monitored and data were collected. We found that pacing occurred in 25 carotid lesions during balloon predilatation; pacemakers were activated transiently in 25 patients. The longest pacing continued for 1 day. Among cases with pacemaker activation, 1 patient developed post-procedural symptomatic hypotension that lasted for 4 days. No related complications were observed. It was, therefore, concluded that pacing was technically effective in producing electrical ventricular responses and was hemodynamically effective in 25 carotid lesions which underwent balloon predilatation. The prophylactic use of a temporary transvenous cardiac pacemaker during CAS was rapid and effective in controlling peri-operative hemodynamic instability and preventing stroke and other complications. The prophylactic use of temporary pacemaker is particularly recommended for patients at high risk for developing hemodynamic instability. 相似文献
992.
Yu Dahai Sun Sanyuan Lu Hong Zhao Di Zhou Chong 《Cell biochemistry and biophysics》2013,67(1):175-180
Esophageal carcinoma (EC) is an aggressive and the third most common cancer of the digestive tract with poor prognosis. Replication protein A (RPA) is critically required for DNA replication and its elevated expression has been observed in many malignant tumors. In this study, we investigated the expression of RPA1 and RPA2, subunits of RPA, and assessed their prognostic value in EC patients. We analyzed immunohistochemically the expression of RPA1 and RPA2 proteins in 48 EC resection specimens in relation with clinicopathological parameters and survival. We observed a significant elevated (P < 0.001) RPA1 and RPA2 expressions (labeling index) in the tumor than adjacent non-tumor tissues. In addition, both RPA1 and RPA2 labeling index in lymph node metastasis patients was significantly higher (both P = 0.000) than patients without lymph node metastasis. However, RPA1 and RPA2 labeling index in early stage was significantly lower (P = 0.000 and P = 0.002, respectively) than that of late stage EC patients. Importantly, patient’s survival at early stage was significantly higher (P = 0.016) than late stage EC and lymph node metastasis and RPA1 expression was associated with adverse patient’s outcome in multivariate analysis (P < 0.05 and P < 0.00, respectively). In conclusion, RPA1 could be a useful prognostic indicator in patients with esophageal carcinoma and might be a future attractive therapeutic target for regulation by tumor suppressors. 相似文献
993.
Abstract Enriched nutrient patches within natural soil represent an important source of nutrients for tree growth. In the present study, pot experiments in a heterogeneous nutrient environment were conducted to investigate the influence of light conditions and interspecific competition on the root foraging traits and seedling growth of Pinus massoniana and Schima superba. The root foraging scale and the whole-seedling biomass of both species were decreased by shading. The result of this treatment was a lower sensitivity to nutrient heterogeneity in plants that underwent the shading treatment than in plants that were exposed to full-light conditions. The above-ground biomass and whole-seedling biomass of S. superba were not affected by competition with P. massoniana. In contrast, the above-ground biomass and whole-seedling biomass of P. massoniana were negatively affected by competition with S. superba. The more rapid rate of root extension and the more efficient resource uptake of S.superba appear to explain this effect. The species-specific patterns of the influence of environmental factors on foraging ability and seedling growth should be given thorough consideration and should be applied to afforestation and to the management of tree plantations. 相似文献
994.
The primary culture of mirror carp snout and caudal fin tissues and the isolation of Koi herpesvirus
Jingxiang Zhou Hao Wang Xia Zhu Xingwei Li Wenliang Lv Dongming Zhang 《In vitro cellular & developmental biology. Animal》2013,49(9):734-742
The explosive Koi herpesvirus (KHV) epidemic has caused the deaths of a large number of carp and carp variants and has produced serious economic losses. The mirror carp (Cyprinus carpio var. specularis) exhibits strong environmental adaptability and its primary cells can be used to isolate KHV. This study utilized the tissue explant method to systematically investigate primary cell culture conditions for mirror carp snout and caudal fin tissues. We demonstrated that cells from these two tissue types had strong adaptability, and when cultured in Medium 199 (M199) containing 20% serum at 26 to 30°C, the cells from the snout and caudal fin tissues exhibited the fastest egress and proliferation. Inoculation of these two cell types with KHV-infected fish kidney tissues produced typical cytopathic effects; additionally, identification by electron microscopy, and PCR indicated that KHV could be isolated from both cell types. 相似文献
995.
Xiangxiang Shan Yufeng Miao Rengen Fan Changzhi Song Guangzhou Wu Zhengqiang Wan Jian Zhu Guan Sun Wenzhang Zha Xiangming Mu Guangjun Zhou Yan Chen 《In vitro cellular & developmental biology. Animal》2013,49(8):576-582
In this study, we aimed to study the role of growth factor receptor-bound protein 2 (Grb2) in palmitic acid-induced steatosis and other “fatty liver” symptoms in vitro. HepG2 cells, with or without stably suppressed Grb2 expression, were incubated with palmitic acid for 24 h to induce typical clinical “fatty liver” features, including steatosis, impaired glucose metabolism, oxidative stress, and apoptosis. MTT and Oil Red O assays were applied to test cell viability and fat deposition, respectively. Glucose uptake assay was used to evaluate the glucose utilization of cells. Quantitative polymerase chain reaction and Western blot were used to measure expressional changes of key markers of insulin signaling, lipid/glucose metabolism, oxidative stress, and apoptosis. After 24-h palmitic acid induction, increased fat accumulation, reduced glucose uptake, impaired insulin signaling, enhanced oxidative stress, and increased apoptosis were observed in HepG2 cells. Suppression of Grb2 in HepG2 significantly reduced fat accumulation, improved glucose metabolism, ameliorated oxidative stress, and restored the activity of insulin receptor substrate-1/Akt and MEK/ERK pathways. In addition, Grb2 deficiency attenuated hepatic apoptosis shown by reduced activation of caspase-3 and fluorescent staining. Modulation of Bcl-2 and Bak1 also contributed to reduced apoptosis. In conclusion, suppression of Grb2 expression in HepG2 cells improved hepatic steatosis, glucose metabolism, oxidative stress, and apoptosis induced by palmitic acid incubation partly though modulating the insulin signaling pathway. 相似文献
996.
Xiao Wang Heng-Fu Bu Wei Zhong Akihiro Asai Zhanxiang Zhou Xiao-Di Tan 《Molecular medicine (Cambridge, Mass.)》2013,19(1):170-182
Efferocytosis is a unique phagocytic process for macrophages to remove apoptotic cells in inflammatory loci. This event is maintained by milk fat globule-EGF factor 8 (MFG-E8), but attenuated by high mobility group box 1 (HMGB1). Alcohol abuse causes injury and inflammation in multiple tissues. It alters efferocytosis, but precise molecular mechanisms for this effect remain largely unknown. Here, we showed that acute exposure of macrophages to alcohol (25 mmol/L) inhibited MFG-E8 gene expression and impaired efferocytosis. The effect was mimicked by hydrogen peroxide. Moreover, N-acetylcysteine (NAC), a potent antioxidant, blocked acute alcohol effect on inhibition of macrophage MFG-E8 gene expression and efferocytosis. In addition, recombinant MFG-E8 rescued the activity of alcohol-treated macrophages in efferocytosis. Together, the data suggest that acute alcohol exposure impairs macrophage efferocytosis via inhibition of MFG-E8 gene expression through a reactive oxygen species dependent mechanism. Alcohol has been found to suppress or exacerbate immune cell activities depending on the length of alcohol exposure. Thus, we further examined the role of chronic alcohol exposure on macrophage efferocytosis. Interestingly, treatment of macrophages with alcohol for seven days in vitro enhanced MFG-E8 gene expression and efferocytosis. However, chronic feeding of mice with alcohol caused increase in HMGB1 levels in serum. Furthermore, HMGB1 diminished efferocytosis by macrophages that were treated chronically with alcohol, suggesting that HMGB1 might attenuate the direct effect of chronic alcohol on macrophage efferocytosis in vivo. Therefore, we speculated that the balance between MFG-E8 and HMGB1 levels determines pathophysiological effects of chronic alcohol exposure on macrophage efferocytosis in vivo. 相似文献
997.
Jianxin Wan Xueli Zhou Jiong Cui Zhenhuan Zou Yanfang Xu Danyu You 《Molecular biotechnology》2013,54(1):92-100
Injured renal tubular epithelial cells (RTECs) have been recently thought to directly contribute to the accumulation of myofibroblasts in renal tubulointerstitial fibrosis through a process of epithelial to mesenchymal transition (EMT). However, the factors inducing RTECs to undergo EMT and the underlying mechanisms need to be further elucidated. This study aimed to determine the EMT-inducing activity of proinflammatory cytokine TNF-α and the role for complement 3 (C3) in this activity in an in vitro model of human RTECs (HK-2 cells). Wild type HK-2 cells were treated with TNF-α, IFN-γ or C3a; C3 siRNA- or control siRNA-carrying HK-2 cells were treated with TNF-α. Changes in the cell morphology and phenotype were assessed by microscopy, RT-PCR, western blotting, and immunostaining. TNF-α effectively induced HK-2 cells to express C3 and to transform into morphologically myofibroblast-like cells that lost E-cadherin (a classical epithelial cell marker) expression but acquired alpha-smooth muscle actin (α-SMA, a classical myofibroblast differentiation marker) expression. C3 siRNA robustly attenuated all the morphologic and phenotypic changes induced by TNF-α but the control siRNA showed no effect. Our preliminary observations suggest that TNF-α may induce EMT in RTECs through inducing C3 expression. 相似文献
998.
Zhiyu Dai Yifei Chen Weiwei Qi Lijun Huang Yang Zhang Ti Zhou 《Preparative biochemistry & biotechnology》2013,43(1):123-136
A unique serpin, kallistatin, displays vasodilatory, antiangiogenic, anti-inflammatory, and antioxidant activity. Difficulty and low efficacy of obtaining recombinant kallistatin limit the wide investigation of its biological and pathological function. The present study employed a codon optimization algorithm to redesign the kallistatin gene and achieved a high yield of recombinant kallistatin protein. The kallistatin codons were redesigned for a more suitable Escherichia coli host without altering amino acids. Base composition and GC% content were compared between synthetic optimized kallistatin (opti-kallistatin) and wild-type kallistatin (wt-kallistatin). Both opti-kallistatin and wt-kallistatin were purified using Ni-NTA His-binding resins through fast protein liquid chromatography (FPLC). The identity and purity of kallistatin were confirmed by Coomassie blue staining, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and Western blot analysis. The output of opti-kallistatin protein was ~2-fold increase (2.09 ± 0.23 mg/L) compared to wt-kallistatin (1.05 ± 0.2 mg/L). These results suggest that more common codon optimization in the E. coli host significantly increases the yield of heterologous human protein yields. This approach will remarkably facilitate the further investigation of kallistatin in vitro and in vivo. 相似文献
999.
Xuanwei Zhou Qizhang Li Jingya Zhao Juan Lin Yizhou Yin 《Preparative biochemistry & biotechnology》2013,43(4):369-380
Abstract Four different DNA extraction methods were used to extract genomic DNA of the medicinal mushroom Lingzhi from its developing stage materials, such as mycelium, dry fruiting body, or sliced and spore powder or sporoderm‐broken spore powder. The DNA samples were analyzed using agarose gel electrophoresis, UV spectrophotometer, and PCR amplification. According to the average yields and purity of DNA, high salt concentrations and low pH methods were the best for DNA extraction. The mycelia and sporoderm‐broken spore powder yielded higher and purer DNA. The method developed could effectively eliminate the influence of the secondary metabolites to DNA extraction. The DNA samples extracted from the developed method could be successfully used for PCR applications. 相似文献
1000.
Yahui Shen Guixian Song Yaoqiu Liu Lijuan Zhou Hailang Liu Xiangqing Kong Yanhui Sheng Kejiang Cao Lingmei Qian 《Cell biochemistry and biophysics》2013,66(1):139-146
Fatty acid–binding protein 3 (FABP3) facilitates the movement of fatty acids in cardiac muscle. Previously, we reported that FABP3 is highly upregulated in the myocardium of ventricular septal defect patients and overexpression of FABP3 inhibited proliferation and promoted apoptosis in embryonic carcinoma cells (P19 cells). In this study, we aimed to investigate the effect of FABP3 gene silencing on P19 cell differentiation, proliferation and apoptosis. We used RNA interference and a lentiviral-based vector system to create a stable FABP3-silenced P19 cell line; knockdown of FABP3 was confirmed by quantitative real-time PCR. Expression analysis of specific differentiation marker genes using quantitative real-time PCR and observation of morphological changes using an inverted microscope revealed that knockdown of FABP3 did not significantly affect the differentiation of P19 cells into cardiomyocytes. CCK-8 proliferation assays and cell cycle analysis demonstrated that FABP3 gene silencing significantly inhibited P19 cell proliferation. Furthermore, Annexin V-FITC/propidium iodide staining and the caspase-3 activity assay revealed that FABP3 gene silencing significantly promoted serum starvation–induced apoptosis in P19 cells. In agreement with our previous research, these results demonstrate that FABP3 may play an important role during embryonic heart development, and that either overexpression or silencing of FABP3 will lead to an imbalance between proliferation and apoptosis, which may result in embryonic cardiac malformations. 相似文献