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991.
Jing Han Hua Liang Jianhua Yi Wuhong Tan Shulan He Sen Wang Feng Li Xiaofang Wu Jing Ma Xiaowei Shi Xiong Guo Chuanyi Bai 《Biological trace element research》2017,175(2):396-404
The effects of selenium (Se)-deficient diet on the liver were evaluated by using growing rats which were fed with normal and Se-deficient diets, respectively, for 109 days. The results showed that rats fed with Se-deficient diet led to a decrease in Se concentration in the liver, particularly among male rats from the low-Se group. This causes alterations to the ultrastructure of hepatocytes with condensed chromatin and swelling mitochondria observed after low Se intake. Meanwhile, pathological changes and increased fibrosis in hepatic periportal were detected by hematoxylin and eosin and Masson’s trichrome staining in low-Se group. Furthermore, through immunohistochemistry (IHC) staining, higher expressions of metalloproteinases (MMP1/3) and their tissue inhibitors of metalloproteinases (TIMP1/3) were observed in the hepatic periportal of rats from the low-Se group. However, higher expressions of MMP1/3 and lower expressions of TIMP1/3 were detected in hepatic central vein and hepatic sinusoid. In addition, upregulated expressions of MMP1/3 and downregulated expressions of TIMP1/3 at the messenger RNA (mRNA) and protein levels also appeared to be relevant to low Se intake. In conclusion, Se-deficient diet could cause low Se concentration in the liver, alterations of hepatocyte ultrastructure, differential expressions of MMP1/3 and TIMP1/3 as well as fibrosis in the liver hepatic periportal. 相似文献
992.
Wang-Shan Zheng Yao-Xi He Chao-Ying Cui Ouzhuluobu Dejiquzong Yi Peng Cai-Juan Bai Duojizhuoma Gonggalanzi Bianba Baimakangzhuo Yong-Yue Pan Qula Kangmin Cirenyangji Baimayangji Wei Guo Yangla Hui Zhang Xiao-Ming Zhang Yong-Bo Guo Shu-Hua Xu Hua Chen Sheng-Guo Zhao Yuan Cai Shi-Ming Liu Tian-Yi Wu Xue-Bin Qi Bing Su 《动物学研究》2017,38(3)
The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway,as suggested by earlier studies.To test the adaptive role of the previously reported candidate gene EP300 (histone acetyltransferase p300),we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans.The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans,with a group of variants showing allelic divergence between Tibetans and lowland reference populations,including Han Chinese,Europeans,and Africans.Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation.More importantly,genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide (NO) concentration.Collectively,we propose that EP300 harbors adaptive variants in Tibetans,which might contribute to high-altitude adaptation through regulating NO production. 相似文献
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995.
TNF‐α promotes survival and migration of MSCs under oxidative stress via NF‐κB pathway to attenuate intimal hyperplasia in vein grafts 下载免费PDF全文
Xiao Bai Jie Xi Yanwen Bi Xin Zhao Weidong Bing Xiangbin Meng Yimin Liu Zhonglai Zhu Guangmin Song 《Journal of cellular and molecular medicine》2017,21(9):2077-2091
The oxidative stress caused by endothelial injury is involved in intimal hyperplasia (IH) in vein grafts. Mesenchymal stem cells (MSCs) can home to injured intima and promote endothelial repair. However, MSC apoptosis is increased accompanied by decreased functional activity under oxidative stress. Thus, we investigate whether tumour necrosis factor‐α (TNF‐α) can promote the survival and activity of MSCs under oxidative stress to reduce IH more effectively, and establish what role the NF‐κB pathway plays in this. In this study, we preconditioned MSCs with TNF‐α (TNF‐α‐PCMSCs) for 24 hrs and measured the activation of the IKK/NF‐κB pathway. EdU and transwell assays were performed to assess proliferation and migration of TNF‐α‐PCMSCs. Apoptosis and migration of TNF‐α‐PCMSCs were evaluated in conditions of oxidative stress by analysis of the expression of Bcl‐2 and CXCR4 proteins. TNF‐α‐PCMSCs were transplanted into a vein graft model, so that cell homing could be tracked, and endothelial apoptosis and IH of vein grafts were measured. The results demonstrated that TNF‐α promotes proliferation and migration of MSCs. Furthermore, survival and migration of TNF‐α‐PCMSCs under oxidative stress were both enhanced. A greater number of MSCs migrated to the intima of vein grafts after preconditioning with TNF‐α, and the formation of neointima was significantly reduced. These effects could be partially abolished by IKK XII (NF‐κB inhibitor). All these results indicate that preconditioning with TNF‐α can promote survival and migration of MSCs under oxidative stress via the NF‐κB pathway and thus attenuate IH of vein grafts. 相似文献
996.
Effect of the interaction between MiR‐200b‐3p and DNMT3A on cartilage cells of osteoarthritis patients 下载免费PDF全文
Weiwei Wang Yujie Zhang Liqing Hu Jun Wang Yuan Wang Naizhou Guo 《Journal of cellular and molecular medicine》2017,21(10):2308-2316
The aim of this research is to explore the effect of miR‐200b‐3p targeting DNMT3A on the proliferation and apoptosis of osteoarthritis (OA) cartilage cells. Quantitative RT‐PCR was performed to analyse the expression of miR‐200b‐3p, DNMT3A, MMP1, MMP3, MMP9, MMP13 and COL II in normal and OA cartilage tissues. The dual‐luciferase reporter assay and Western blot assay were conducted to confirm the targeting relationship between miR‐200b‐3p and DNMT3A. We also constructed eukaryotic expression vector to overexpress miR‐200b‐3p and DNMT3A. We detected the expression level of MMPs and COL II in stable transfected cartilage cells using RT‐PCR and Western blot. Cell proliferation and apoptosis were evaluated using the MTS, pellet culture and Hoechst 33342 staining method. Finally, we explored the effect of miR‐200b‐3p targeting DNMT3A on the proliferation and apoptosis of OA cartilage cells. The results of RT‐PCR indicated that both miR‐200b‐3p and COL II were down‐regulated in OA cartilage tissues, while the expression of DNMT3A and MMPs was up‐regulated in OA cartilage tissues. The expressions of DNMT3A, MMPs and COL II detected by Western blot showed the same trend of the results of RT‐PCR. The dual‐luciferase reporter assay and Western blot assay confirmed the targeting relationship between miR‐200b‐3p and DNMT3A. In overexpressed miR‐200b‐3p cartilage cells, DNMT3A and MMPs were significantly down‐regulated, COL II was significantly up‐regulated, cell viability was enhanced and apoptosis rate was decreased (P < 0.05). In overexpressed DNM3T cartilage cells, MMPs were significantly up‐regulated, COL II was significantly down‐regulated, cell viability was weakened and apoptosis rate was increased (P < 0.05). MiR‐200b‐3p inhibited the secretion of MMPs, promoted the synthesis of COL II and enhanced the growth and proliferation of OA cartilage cells through inhibiting the expression of DNMT3A. 相似文献
997.
Chunyu?ChenEmail author Ni?Bai Yan?Zhang Lina?Jiao Mingzhu?Xia Gang?Chen 《Journal of molecular modeling》2017,23(1):32
In this work, the molecular modeling method was performed to study adsorption interaction between PAMAM molecules of different generations and silicic acid molecules, and the inhibition effect on silica scale were discussed. The results show that adsorption energies of PAMAM molecule of generation 1.0 with amine-terminated groups are stronger than those of generation 1.5 with terminated carboxyl group. The composition of adsorption interactions are the dominating electrostatic interactions and van de Waals interactions as well as H-bond interactions. It is qualitatively discussed that the inhibition effect of generation 1.0 on silica scale is stronger than that of generation 1.5 in the neutral solution. 相似文献
998.
Anna C. Peterson Bruno M. Ghersi Fernando Alda Cadhla Firth Matthew J. Frye Ying Bai Lynn M. Osikowicz Claudia Riegel W. Ian Lipkin Michael Y. Kosoy Michael J. Blum 《EcoHealth》2017,14(4):771-782
It is becoming increasingly likely that rodents will drive future disease epidemics with the continued expansion of cities worldwide. Though transmission risk is a growing concern, relatively little is known about pathogens carried by urban rats. Here, we assess whether the diversity and prevalence of Bartonella bacteria differ according to the (co)occurrence of rat hosts across New Orleans, LA (NO), where both Norway (Rattus norvegicus) and roof rats (Rattus rattus) are found, relative to New York City (NYC) which only harbors Norway rats. We detected human pathogenic Bartonella species in both NYC and New Orleans rodents. We found that Norway rats in New Orleans harbored a more diverse assemblage of Bartonella than Norway rats in NYC and that Norway rats harbored a more diverse and distinct assemblage of Bartonella compared to roof rats in New Orleans. Additionally, Norway rats were more likely to be infected with Bartonella than roof rats in New Orleans. Flea infestation appears to be an important predictor of Bartonella infection in Norway rats across both cities. These findings illustrate that pathogen infections can be heterogeneous in urban rodents and indicate that further study of host species interactions could clarify variation in spillover risk across cities. 相似文献
999.
Role of Microstructure in Oxygen Induced Photodegradation of Methylammonium Lead Triiodide Perovskite Films 下载免费PDF全文
Qing Sun Paul Fassl David Becker‐Koch Alexandra Bausch Boris Rivkin Sai Bai Paul E. Hopkinson Henry J. Snaith Yana Vaynzof 《Liver Transplantation》2017,7(20)
This paper investigates the impact of microstructure on the degradation rate of methylammonium lead triiodide (MAPbI3) perovskite films upon exposure to light and oxygen. By comparing the oxygen induced degradation of perovskite films of different microstructure–fabricated using either a lead acetate trihydrate precursor or a solvent engineering technique–it is demonstrated that films with larger and more uniform grains and better electronic quality show a significantly reduced degradation compared to films with smaller, more irregular grains. The effect of degradation on the optical, compositional, and microstructural properties of the perovskite layers is characterized and it is demonstrated that oxygen induced degradation is initiated at the layer surface and grain boundaries. It is found that under illumination, irreversible degradation can occur at oxygen levels as low as 1%, suggesting that degradation can commence already during the device fabrication stage. Finally, this work establishes that improved thin‐film microstructure, with large uniform grains and a low density of defects, is a prerequisite for enhanced stability necessary in order to make MAPbI3 a promising long lived and low cost alternative for future photovoltaic applications. 相似文献
1000.
Open‐Structured V2O5·nH2O Nanoflakes as Highly Reversible Cathode Material for Monovalent and Multivalent Intercalation Batteries 下载免费PDF全文
Huali Wang Xuanxuan Bi Ying Bai Chuan Wu Sichen Gu Shi Chen Feng Wu Khalil Amine Jun Lu 《Liver Transplantation》2017,7(14)
The high‐capacity cathode material V2O5·n H2O has attracted considerable attention for metal ion batteries due to the multielectron redox reaction during electrochemical processes. It has an expanded layer structure, which can host large ions or multivalent ions. However, structural instability and poor electronic and ionic conductivities greatly handicap its application. Here, in cell tests, self‐assembly V2O5·n H2O nanoflakes shows excellent electrochemical performance with either monovalent or multivalent cation intercalation. They are directly grown on a 3D conductive stainless steel mesh substrate via a simple and green hydrothermal method. Well‐layered nanoflakes are obtained after heat treatment at 300 °C (V2O5·0.3H2O). Nanoflakes with ultrathin flower petals deliver a stable capacity of 250 mA h g?1 in a Li‐ion cell, 110 mA h g?1 in a Na‐ion cell, and 80 mA h g?1 in an Al‐ion cell in their respective potential ranges (2.0–4.0 V for Li and Na‐ion batteries and 0.1–2.5 V for Al‐ion battery) after 100 cycles. 相似文献