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991.
苦参素对肾间质纤维化大鼠单核巨噬细胞浸润及MCP-1表达的影响 总被引:3,自引:0,他引:3
目的 观察苦参素对肾间质纤维化大鼠单核巨噬细胞(MC/MP)浸润,MCP-1及Ⅰ型胶原表达的影响。方法 大鼠行单侧输尿管结扎(UUO)建立肾小管间质纤维化模型。实验分为3组:假手术组,UUO组,苦参素治疗组。治疗组在UUO的基础上每天以苦参素100mg/Kg腹腔注射。各组于术后第14d分别处死5只大鼠。用PAS及Masson染色法观察肾脏病理改变。用免疫组织化学法观察肾间质ED-1阳性的MC/MP细胞浸润,单核细胞趋化蛋白-1(MCP-1)及Ⅰ型胶原(ColⅠ)的表达。结果 苦参素治疗组肾间质MC/MP细胞浸润数及MCP-1,ColⅠ的表达显著低于UUO组,肾小管变性和肾间质纤维化的程度也明显减轻。结论 苦参素可下调UUO大鼠肾间质MCP-1的表达,减少MC/MP细胞浸润,减轻肾间质纤维化。 相似文献
992.
Transgene flow to hybrid rice and its male-sterile lines 总被引:9,自引:0,他引:9
Gene flow from genetically modified (GM) crops to the same species or wild relatives is a major concern in risk assessment.
Transgenic rice with insect and/or disease resistance, herbicide, salt and/or drought tolerance and improved quality has been
successfully developed. However, data on rice gene flow from environmental risk assessment studies are currently insufficient
for the large-scale commercialization of GM rice. We have provided data on the gene flow frequency at 17 distances between
a GM japonica line containing the bar gene as a pollen donor and two indica hybrid rice varieties and four male-sterile (ms) lines. The GM line was planted in a 640m2 in an isolated experimental plot (2.4 ha), which simulates actual conditions of rice production with pollen competition.
Results showed that: (1) under parallel plantation at the 0-m zone, the transgene flow frequency to the ms lines ranged from
3.145 to 36.116% and was significantly higher than that to hybrid rice cultivars (0.037–0.045%). (2) Gene flow frequency decreased
as the distance increased, with a sharp cutoff point at about 1–2 m; (3) The maximum distance of transgene flow was 30–40 m
to rice cultivars and 40–150 m to ms lines. We believe that these data will be useful for the risk assessment and management
of transgenic rice lines, especially in Asia where 90% of world's rice is produced and hybrid rice varieties are extensively
used.
Shirong Jia, Feng Wang and Lei Shi contributed equally to this investigation. 相似文献
993.
A novel third-generation biosensor for hydrogen peroxide (H2O2) was developed by self-assembling gold nanoparticles to hollow porous thiol-functionalized poly(divinylbenzene-co-acrylic acid) (DVB-co-AA) nanospheres. At first, a cleaned gold electrode was immersed in hollow porous thiol-functionalized poly(DVB-co-AA) nanosphere latex to assemble the nanospheres, then gold nanoparticles were chemisorbed onto the thiol groups of the nanospheres. Finally, horseradish peroxidase (HRP) was immobilized on the surface of the gold nanoparticles. The immobilized horseradish peroxidase exhibited direct electrochemical behavior toward the reduction of hydrogen peroxide. The resulting biosensor showed a wide linear range of 1.0 microM-8.0mM and a detection limit of 0.5 microM estimated at a signal-to-noise ratio of 3. Moreover, the studied biosensor exhibited high sensitivity, good reproducibility, and long-term stability. 相似文献
994.
Qing Liu Gezhi Shen Keqin Peng Zhigang Huang Jianhua Tong Mohammed Humayun Kabir Jianhui Wang Jingzhe Zhang Genji Qin Langtao Xiao 《植物学报(英文版)》2015,57(10):819-829
Plant architecture is an important factor for crop production. Some members of microRNA156 (miR156) and their target genes SQUAMOSA Promoter‐Binding Protein‐Like (SPL) were identified to play essential roles in the establishment of plant architecture. However, the roles and regulation of miR156 is not well understood yet. Here, we identified a T‐DNA insertion mutant Osmtd1 (Oryza sativa multi‐tillering and dwarf mutant). Osmtd1 produced more tillers and displayed short stature phenotype. We determined that the dramatic morphological changes were caused by a single T‐DNA insertion in Osmtd1. Further analysis revealed that the T‐DNA insertion was located in the gene Os08g34258 encoding a putative inhibitor I family protein. Os08g34258 was knocked out and OsmiR156f was significantly upregulated in Osmtd1. Overexpression of Os08g34258 in Osmtd1 complemented the defects of the mutant architecture, while overexpression of OsmiR156f in wild‐type rice phenocopied Osmtd1. We showed that the expression of OsSPL3, OsSPL12, and OsSPL14 were significantly downregulated in Osmtd1 or OsmiR156f overexpressed lines, indicating that OsSPL3, OsSPL12, and OsSPL14 were possibly direct target genes of OsmiR156f. Our results suggested that OsmiR156f controlled plant architecture by mediating plant stature and tiller outgrowth and may be regulated by an unknown protease inhibitor I family protein. 相似文献
995.
Ultrastructural observation of mesophyll cells and temporal expression profiles of the genes involved in transitory starch metabolism in flag leaves of wheat after anthesis 下载免费PDF全文
996.
997.
Chunyan Liu Wenjuan Mei Juan Tang Qiongjing Yuan Ling Huang Miaomiao Lu Lin Wu Zhangzhe Peng Jie Meng Huixiang Yang Hong Shen Ben Lv Gaoyun Hu Lijian Tao 《PloS one》2015,10(6)
Background
Inflammation has a crucial role in renal interstitial fibrosis, which is the common pathway of chronic kidney diseases. Mefunidone (MFD) is a new compound which could effectively inhibit the proliferation of renal fibroblasts in vitro. However, the overall effect of Mefunidone in renal fibrosis remains unknown.Methods
Sprague-Dawley rats were randomly divided intro 6 groups: sham operation, unilateral ureteral obstruction (UUO), UUO/Mefunidone (25, 50, 100mg/kg/day) and UUO/PFD (500mg/kg/day). The rats were sacrificed respectively on days 3, 7, and 14 after the operation. Tubulointerstitial injury index, interstitial collagen deposition, expression of fibronectin (FN), α-smooth muscle actin (α-SMA), type I and III collagen and the number of CD3+ and CD68+ cells were determined. The expressions of proinflammatory cytokines, p-ERK, p-IκB, and p-STAT3 were measured in human renal proximal tubular epithelial cells of HK-2 or macrophages.Results
Mefunidone treatment significantly attenuated tubulointerstitial injury, interstitial collagen deposition, expression of FN, α-SMA, type I and III collagen in the obstructive kidneys, which correlated with significantly reduced the number of T cells and macrophages in the obstructive kidneys. Mechanistically, Mefunidone significantly inhibited tumor necrosis factor-α (TNF-α-) or lipopolysaccharide (LPS)-induced production of proinflammatory cytokines. This effect is possibly due to the inhibition of phosphorylation of ERK, IκB, and STAT3.Conclusion
Mefunidone treatment attenuated tubulointerstitial fibrosis in a rat model of UUO, at least in part, through inhibition of inflammation. 相似文献998.
XiYou Wang CuiLong Liu ShaoDan Li Yong Xu Ping Chen Yi Liu Qiang Ding Wasilijiang Wahafu BaoFa Hong MingHui Yang 《PloS one》2015,10(3)
The aim of the present study was to examine whether hypoxia preconditioning could improve therapeutic effects of adipose derived mesenchymal stem cells (AMSCs) for diabetes induced erectile dysfunction (DED). AMSCs were pretreated with normoxia (20% O2, N-AMSCs) or sub-lethal hypoxia (1% O2, H-AMSCs). The hypoxia exposure up-regulated the expression of several angiogenesis and neuroprotection related cytokines in AMSCs, including vascular endothelial growth factor (VEGF) and its receptor FIK-1, angiotensin (Ang-1), basic fibroblast growth factor (bFGF), brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), stromal derived factor-1 (SDF-1) and its CXC chemokine receptor 4 (CXCR4). DED rats were induced via intraperitoneal injection of streptozotocin (60 mg/kg) and were randomly divided into three groups—Saline group: intracavernous injection with phosphate buffer saline; N-AMSCs group: N-AMSCs injection; H-AMSCs group: H-AMSCs injection. Ten rats without any treatment were used as normal control. Four weeks after injection, the mean arterial pressure (MAP) and intracavernosal pressure (ICP) were measured. The contents of endothelial, smooth muscle, dorsal nerve in cavernoursal tissue were assessed. Compared with N-AMSCs and saline, intracavernosum injection of H-AMSCs significantly raised ICP and ICP/MAP (p<0.05). Immunofluorescent staining analysis demonstrated that improved erectile function by MSCs was significantly associated with increased expression of endothelial markers (CD31 and vWF) (p<0.01) and smooth muscle markers (α-SMA) (p<0.01). Meanwhile, the expression of nNOS was also significantly higher in rats receiving H-AMSCs injection than those receiving N-AMSCs or saline injection. The results suggested that hypoxic preconditioning of MSCs was an effective approach to enhance their therapeutic effect for DED, which may be due to their augmented angiogenesis and neuroprotection. 相似文献
999.
Daihui Peng Feng Shi Gang Li Drew Fralick Ting Shen Meihui Qiu Jun Liu Kaida Jiang Dinggang Shen Yiru Fang 《PloS one》2015,10(3)
Major depressive disorder (MDD) is accompanied by atypical brain structure. This study first presents the alterations in the cortical surface of patients with MDD using multidimensional structural patterns that reflect different neurodevelopment. Sixteen first-episode, untreated patients with MDD and 16 matched healthy controls underwent a magnetic resonance imaging (MRI) scan. The cortical maps of thickness, surface area, and gyrification were examined using the surface-based morphometry (SBM) approach. Increase of cortical thickness was observed in the right posterior cingulate region and the parietal cortex involving the bilateral inferior, left superior parietal and right paracentral regions, while decreased thickness was noted in the parietal cortex including bilateral pars opercularis and left precentral region, as well as the left rostral-middle frontal regions in patients with MDD. Likewise, increased or decreased surface area was found in five sub-regions of the cingulate gyrus, parietal and frontal cortices (e.g., bilateral inferior parietal and superior frontal regions). In addition, MDD patients exhibited a significant hypergyrification in the right precentral and supramarginal region. This integrated structural assessment of cortical surface suggests that MDD patients have cortical alterations of the frontal, parietal and cingulate regions, indicating a vulnerability to MDD during earlier neurodevelopmental process. 相似文献
1000.
随着城市发展面临的生态问题日益显著,部分研究者试图通过对自然生态系统进行类比来寻求解决途径,城市代谢理论应运而生。当以系统科学来研究城市生态系统时,哲学思想的引入为探索和城市及城市代谢的内涵提供了最原始的桥梁。因此,在介绍城市代谢内涵与研究进展的基础上,融合产业、家庭、社会等多尺度代谢理论,对城市代谢的边界进行扩展,将其分为狭义与广义两类,结合亚里士多德的"四因说"对其质料因(组分)、形式因(结构)、动力因(驱动力)和目的因(功能)进行识别分析,据此将城市代谢研究方法归纳为质料、形式和混合研究方法三类,并提出未来研究的主要动向和解决手段。城市代谢"四因图"可为相关研究者提供参考。 相似文献