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101.
Min Xia Daxin Chen Valeria Endresz Ildiko Faludi Andrea Szabo Eva Gonczol Vijay Kakkar Xinjie Lu 《PloS one》2013,8(12)
Objective
To investigate the antigenic effect of a peptide containing two epitopes of Chlamydia pneumoniae (Cpn) on atherosclerotic lesion formation in mice infected with Cpn.Materials and Methods
Six-week-old Apobtm2SgyLdlrtm1Her/J mice were immunized using a repetitive immunization multiple-sites strategy with KLH-conjugated peptides derived from the major outer membrane protein and the putative outer membrane protein 5 of Cpn. Mice were fed a high-fat diet and infected with Cpn twice during the 10-week diet period. Lesions were evaluated histologically; local and systemic immune responses were analyzed by immunohistochemistry of aorta samples and cytokine measurements in plasma samples and splenocyte supernatants.Results
Mice immunized with the combined Cpn peptide showed a greater reduction in lesion size compared to mice immunized with either epitope alone [54.7% vs 39.8% or 41.72%] and was also associated with a significant decrease in lesion area in descending aortas compared with those in controls (88.9% for combined Cpn peptide, 81.9% for MOMP peptide and 75.7% for Omp5, respectively). This effect was associated with a shift in the cellular composition of plaques towards decreased inflammatory cell and increased regulatory T-cell content. Additionally, the effect was also connected with decreased secretion of proinflammatory cytokines and increased production of anti-inflammatory cytokines demonstrated in plasma and in supernatant on stimulated spleen cells.Conclusions
Atherosclerotic lesion formation may be promoted by Cpn infection in the presence of a high-fat diet, and reduced by immunization with the combined Cpn peptide. The combined peptide has more potential than either epitope alone in reducing atherosclerotic lesion development through Treg expansion. 相似文献102.
Xin-Xia Feng Mei Liu Wei Yan Zhen-Zhen Zhou Yu-Jia Xia Wei Tu Pei-Yuan Li De-An Tian 《PloS one》2013,8(11)
In addition to being an important mediator of migration and invasion of tumor cells, β3 integrin can also enhance TGF-β1 signaling. However, it is not known whether β3 might influence the induction of metastatic phenotype of tumor cells, especially non-metastatic tumor cells which express low level of β3. Here we report that H2O2 and HOCl, the reactive oxygen species produced by neutrophils, could cooperate with TGF-β1 to induce metastatic phenotype of non-metastatic hepatocellular carcinoma (HCC) cells. TGF-β1/H2O2/HOCl, but not TGF-β1 or H2O2/HOCl, induced β3 expression by triggering the enhanced activation of p38 MAPK. Intriguingly, β3 in turn promoted TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of HCC cells by enhancing TGF-β1 signaling. β3 promoted TGF-β1/H2O2/HOCl-induced expression of itself via positive feed-back effect on p38 MAPK activation, and also promoted TGF-β1/H2O2/HOCl-induced expression of α3 and SNAI2 by enhancing the activation of ERK pathway, thus resulting in higher invasive capacity of HCC cells. By enhancing MAPK activation, β3 enabled TGF-β1 to augment the promoting effect of H2O2/HOCl on anoikis-resistance of HCC cells. TGF-β1/H2O2/HOCl-induced metastatic phenotype was sufficient for HCC cells to extravasate from circulation and form metastatic foci in an experimental metastasis model in nude mice. Inhibiting the function of β3 could suppress or abrogate the promoting effects of TGF-β1/H2O2/HOCl on invasive capacity, anoikis-resistance, and extravasation of HCC cells. These results suggest that β3 could function as a modulator to promote TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of non-metastatic tumor cells, and that targeting β3 might be a potential approach in preventing the induction of metastatic phenotype of non-metastatic tumor cells. 相似文献
103.
Ying Zhang Jing Hu Hong-Jun Lu Jian-Ping Li Ning Wang Wei-Wei Li Yong-Chun Zhou Jun-Yue Liu Sheng-Jun Wang Jing Wang Xia Li Wan-Ling Ma Li-Chun Wei Mei Shi 《PloS one》2013,8(11)
Purpose
To determine the optimal standardized uptake value (SUV) of 18F-fluorodeoxyglucose (18F-FDG) for positron emission tomography (PET) imaging, at which the PET-defined gross tumor volume (GTVPET) best matches with the pathological volume (GTVPATH) in the cervical cancer.Materials and Methods
Ten patients with the cervical cancer who underwent surgery were enrolled in this study. The excised specimens were processed for whole-mount serial sections and H-E staining. The tumor borders were outlined in sections under a microscope, histopathological images were scanned and the GTVPATH calculated. The GTVPET was delineated automatically by using various percentages relative to the maximal SUV and absolute SUV. The optimal threshold SUV was further obtained as the value at which the GTVPET best matched with the GTVPATH.Results
An average of 85±10% shrinkage of tissue was observed after the formalin fixation. The GTVPATH was 13.38±2.80 cm3 on average. The optimal threshold on percentile SUV and absolute SUV were 40.50%±3.16% and 7.45±1.10, respectively. The correlation analysis showed that the optimal percentile SUV threshold was inversely correlated with GTVPATH (p<0.05) and tumor diameter (p<0.05). The absolute SUV was also positively correlated with SUVmax (p<0.05).Conclusion
The pathological volume could provide the more accurate tumor volume. The optimal SUV of FDG for PET imaging by use of GTVPATH as standard for cervical cancer target volume delineation was thus determined in this study, and more cases are being evaluated to substantiate this conclusion. 相似文献104.
105.
Zhi‐Jian Li Guy S. S. Njateng Wen‐Jia He Hong‐Xia Zhang Jian‐Long Gu Shan‐Na Chen Zhi‐Zhi Du 《化学与生物多样性》2013,10(11):2032-2041
The essential oil obtained by hydrodistillation from the aerial parts of Aristolochia delavayi Franch. (Aristolochiaceae), a unique edible aromatic plant consumed by the Nakhi (Naxi) people in Yunnan, China, was investigated using GC/MS analysis. In total, 95 components, representing more than 95% of the oil composition, were identified, and the main constituents found were (E)‐dec‐2‐enal (52.0%), (E)‐dodec‐2‐enal (6.8%), dodecanal (3.35%), heptanal (2.88%), and decanal (2.63%). The essential oil showed strong inhibitory activity (96% reduction) of the production of bacterial volatile sulfide compounds (VSC) by Klebsiella pneumoniae, an effect that was comparable with that of the reference compound citral (91% reduction). Moreover, the antimicrobial activity of the essential oil and the isolated major compound against eight bacterial and six fungal strains were evaluated. The essential oil showed significant antibacterial activity against Providencia stuartii and Escherichia coli, with minimal inhibitory concentrations (MIC) ranging from 3.9 to 62.5 μg/ml. The oil also showed strong inhibitory activity against the fungal strains Trichophyton ajelloi, Trichophyton terrestre, Candida glabrata, Candida guilliermondii, and Cryptococcus neoformans, with MIC values ranging from 3.9 to 31.25 μg/ml, while (E)‐dec‐2‐enal presented a lower antifungal activity than the essential oil. 相似文献
106.
Lanlan Li Jianbin Shi Jing Wang Yimin Gao Linbo Wang Jieqing Wang Xia Ying 《European Journal of Wildlife Research》2013,59(2):179-184
Conflicts between humans and wildlife, especially wild boar (Sus scrofa), have caused serious problems across the world in recent years. It is necessary to effectively control wild boar agricultural damage that may be influenced by many factors. In this study, we collected data on agricultural damage caused by wild boars from November 2009 to October 2010 using field surveys and social interviews in Taohongling National Nature Reserve of Jiangxi Province, China. We constructed models using binary logistic regression analysis to predict damage risks and to identify the factors influencing damage risks. About 8.1 % of croplands were damaged by wild boars, and the damage to rice, cotton, and other crops were not distributed based on their respective availability as shown by the result of a chi-square goodness-of-fit test. Five factors (Japanese silvergrass, soil conditions, terrain, distances to settlements, and water sources) were explained in a model based on damage area (area-based model) with the prediction accuracy being 72.1 %. In addition to these five factors, one additional factor (i.e. distance to forest edge) was retained in a model based on damage frequency (frequency-based model) with the prediction accuracy being 83.1 %. Caution is needed when we apply these two models to predict boar damage to crops, and it is recommended that both models be used in combination to predict the damage probabilities more accurately. 相似文献
107.
Huilin Pan Xia Lu Xiqian Yu Yong‐Sheng Hu Hong Li Xiao‐Qing Yang Liquan Chen 《Liver Transplantation》2013,3(9):1186-1194
Layered sodium titanium oxide, Na2Ti3O7, is synthesized by a solid‐state reaction method as a potential anode for sodium‐ion batteries. Through optimization of the electrolyte and binder, the microsized Na2Ti3O7 electrode delivers a reversible capacity of 188 mA h g?1 in 1 M NaFSI/PC electrolyte at a current rate of 0.1C in a voltage range of 0.0–3.0 V, with sodium alginate as binder. The average Na storage voltage plateau is found at ca. 0.3 V vs. Na+/Na, in good agreement with a first‐principles prediction of 0.35 V. The Na storage properties in Na2Ti3O7 are investigated from thermodynamic and kinetic aspects. By reducing particle size, the nanosized Na2Ti3O7 exhibits much higher capacity, but still with unsatisfied cyclic properties. The solid‐state interphase layer on Na2Ti3O7 electrode is analyzed. A zero‐current overpotential related to thermodynamic factors is observed for both nano‐ and microsized Na2Ti3O7. The electronic structure, Na+ ion transport and conductivity are investigated by the combination of first‐principles calculation and electrochemical characterizations. On the basis of the vacancy‐hopping mechanism, a quasi‐3D energy favorable trajectory is proposed for Na2Ti3O7. The Na+ ions diffuse between the TiO6 octahedron layers with pretty low activation energy of 0.186 eV. 相似文献
108.
Haiyang He Zhirong Mou Wanling Li Lei Fei Yan Tang Ji Zhang Ping Yan Zhengqiong Chen Xia Yang Zigang Shen Jintao Li Yuzhang Wu 《Proteomics》2013,13(7):1121-1132
Rotavirus (RV) infection is the main cause of acute dehydrating diarrhea in infants and young children below 5 years old worldwide. RV infection causes a global shutoff of host proteins as many other viruses do. However, previous studies revealed that RV could selectively upregulated the expression of some host proteins that then played important roles in RV infection. To globally explor such host proteins that were upregulated in early human rotavirus (HRV) infection, proteomic methods were used and a total of ten upregulated host proteins were unambiguously identified. Cyclophilin A (CYPA), a peptidyl‐prolyl cis‐trans isomerase, was among these upregulated host proteins. Following infection, CYPA was recruited to the viroplasm and interacted with HRV structural protein VP2; CYPA reduced host susceptibility to HRV infection and inhibited replication of HRV by repressing the expression of viral proteins. Furthermore, we found that the increased expression of CYPA in enterocytes of small intestine correlated to the period when BALB/c mice became resistant to RV diarrhea. Together, we identified CYPA as a novel host restriction factor that confered protection against RV infection and might contribute to host susceptibility to RV diarrhea. 相似文献
109.
Several plant CDPKs were recently shown to be dual specificity kinases rather than Ser/Thr kinases as traditionally classified by sequence analysis. In the present study we confirm the autophosphorylation of recombinant soybean His6-GmCDPKβ at the Tyr-24 site using sequence- and modification- specific antibodies. Homology modeling of soybean CDPKβ based on recent structures determined for several apicomplexan CDPKs suggested that phosphotyrosine-24 may be inaccessible to phosphatases. However, we report that dephosphorylation of CDPKβ by the protein tyrosine phosphatase 1B, PTP1B, was not restricted in the presence of calcium. Thus, despite conformational changes likely associated with calcium binding to the CDPKs, phosphotyrosine sites remain fully accessible to dephosphorylation suggesting the possibility of conformational breathing and flexing. 相似文献
110.