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991.
Hai-Long Wang Tie-E Zhang Li-Tian Yin Min Pang Li Guan Hong-Li Liu Jian-Hong Zhang Xiao-Li Meng Ji-Zhong Bai Guo-Ping Zheng Guo-Rong Yin 《PloS one》2014,9(9)
Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects a variety of mammals, including humans. An effective vaccine for this parasite is therefore needed. In this study, RH strain T. gondii rhoptry protein 17 was expressed in bacteria as a fusion with glutathione S-transferase (GST) and the recombinant proteins (rTgROP17) were purified via GST-affinity chromatography. BALB/c mice were nasally immunised with rTgROP17, and induction of immune responses and protection against chronic and lethal T. gondii infections were investigated. The results revealed that mice immunised with rTgROP17 produced high levels of specific anti-rTgROP17 IgGs and a mixed IgG1/IgG2a response of IgG2a predominance. The systemic immune response was associated with increased production of Th1 (IFN-γand IL-2) and Th2 (IL-4) cytokines, and enhanced lymphoproliferation (stimulation index, SI) in the mice immunised with rTgROP17. Strong mucosal immune responses with increased secretion of TgROP17-specific secretory IgA (SIgA) in nasal, vaginal and intestinal washes were also observed in these mice. The vaccinated mice displayed apparent protection against chronic RH strain infection as evidenced by their lower liver and brain parasite burdens (59.17% and 49.08%, respectively) than those of the controls. The vaccinated mice also exhibited significant protection against lethal infection of the virulent RH strain (survival increased by 50%) compared to the controls. Our data demonstrate that rTgROP17 can trigger strong systemic and mucosal immune responses against T. gondii and that ROP17 is a promising candidate vaccine for toxoplasmosis. 相似文献
992.
Si-Qiao Liang Xiao-Li Chen Jing-Min Deng Xuan Wei Chen Gong Zhang-Rong Chen Zhi-Bo Wang 《PloS one》2014,9(8)
Background and Objective
A number of studies have assessed the relationship between beta-2 adrenergic receptor (ADRB2) gene polymorphisms and asthma risk. However, the results are inconsistent. A meta-analysis that focused on the association between asthma and all ADRB2 polymorphisms with at least three case-control studies was thus performed.Methods
A literature search of the PubMed, Embase, Web of Science, CNKI, and Wangfang databases was conducted. Odds ratios with 95% confidence intervals were used to assess the strength of associations.Results
Arg16Gly, Gln27Glu, Thr164Ile, and Arg19Cys single nucleotide polymorphisms (SNPs) were identified in 46 case-control studies. The results showed that not all of the SNPs were associated with asthma in the overall population. Significant associations were found for the Arg16Gly polymorphism in the South American population via dominant model comparison (OR = 1.754, 95% CI = 1.179–2.609, I2 = 16.9%, studies = 2, case = 314, control = 237) in an analysis stratified by ethnicity. For the Gln27Glu polymorphism, a protective association was found in children via recessive model comparison (OR = 0.566, 95% CI = 0.417–0.769, I2 = 0.0%, studies = 11, case = 1693, control = 502) and homozygote genotype comparison (OR = 0.610, 95% CI = 0.434–0.856, I2 = 0.0%, studies = 11, case = 1693, control = 1502), and in adults via dominant model comparison (OR = 0.864, 95% CI = 0.768–0.971, I2 = 46.9%, n = 18, case = 3160, control = 3433).Conclusions
None of the ADRB2 gene polymorphisms were reproducibly associated with a risk of asthma across ethnic groups in the general population. 相似文献993.
Xu Zhao Ying Yang Bao-Fa Sun Yue Shi Xin Yang Wen Xiao Ya-Juan Hao Xiao-Li Ping Yu-Sheng Chen Wen-Jia Wang Kang-Xuan Jin Xing Wang Chun-Min Huang Yu Fu Xiao-Meng Ge Shu-Hui Song Hyun Seok Jeong Hiroyuki Yanagisawa Yamei Niu Gui-Fang Jia Wei Wu Wei-Min Tong Akimitsu Okamoto Chuan He Jannie M Rendtlew Danielsen Xiu-Jie Wang Yun-Gui Yang 《Cell research》2014,24(12):1403-1419
994.
Rongbao Gao Jingdong Song Ye Zhang Shumei Zou Tian Bai Xiaodan Li Jianguo Qu Jianfang Zhou Tao Hung 《Virologica Sinica》2014,(2):119-122
正Dear Editor,In March 2013,the first 3 cases of severe disease dueto a novel avian-origin influenza A(H7N9)virus weredetected in the Chinese provinces of Shanghai and Anhui(Gao R,et al.,2013).A total of 339 laboratory-confirmedcases with 100 deaths were reported until January 142014(WHO,2014).To the best of our knowledge,thisis the first time that human infection with the avian in-fluenza A H7N9 subtype has been detected.Prior to this 相似文献
995.
996.
Linqing Zou Haoming Li Guohua Jin Meiling Tian Jianbing Qin Heyan Zhao 《In vitro cellular & developmental biology. Animal》2014,50(3):174-182
Hippocampus is one of the neurogenesis areas in adult mammals, but the function of astrocytes in this area is still less known. In our previous study, the fimbria–fornix (FF)-transected hippocampal extracts promoted the proliferation and neuronal differentiation of radial glial cells in vitro. To explore the effects of hippocampal extracts on gliogenesis, the hippocampal astrocytes were treated by normal or ff-transected hippocampal extracts in vitro. The cells were immunostained by brain lipid-binding protein (BLBP), nestin, and SOX2 to assess their state of activation. The effects of astrocyte-conditioned medium on the neuronal differentiation of hippocampal neural stem cells (NSCs) were also investigated. After treatment of FF-transected hippocampal extracts, the number of BLBP, nestin, and Sox-positive cells were obviously more than the cells which treated by normal hippocampal extracts, these cells maintained a state of activation and the activated astrocyte-conditioned medium also promoted the differentiation of NSCs into more neurons. These findings suggest that the astrocytes can be activated by FF-transected hippocampal extracts and these activated cells also can promote the neuronal differentiation of hippocampal NSCs in vitro. 相似文献
997.
The objective of this study is to assess the clinical role of computed tomography angiography (CTA) in determining the etiology of aneurysmal subarachnoid hemorrhage (ASAH) and selecting the treatment options. A total of 452 patients with ASAH underwent a 64-slice CTA examination to determine the etiology and select the treatment strategies. Digital subtraction angiography (DSA) or clipping operation confirmed the detection from the CTA. The CTA results of 452 patients with ASAH were confirmed through the DSA or clipping operation and the CTA results of 451 cases were consistent with what were seen during the DSA or clipping operation. The treatment choices for 451 patients (99.8 %) were based on the CTA results. A total of 90 cases (19.9 %) underwent endovascular embolization and 362 cases (80.1 %) underwent clipping operation. The other one patient underwent endovascular embolization after the DSA examination due to insufficient information from the CTA. Also, there was one patient who was misdiagnosed in the CTA. In conclusion, a 64-slice CTA can accurately detect intracranial aneurysms and is helpful in choosing the best treatment option. 相似文献
998.
Mike Ran Zou Jian Cao Zongzhi Liu Sung Jin Huh Kornelia Polyak Qin Yan 《The Journal of biological chemistry》2014,289(25):17620-17633
The JmjC domain-containing H3K4 histone demethylase jumonji AT-rich interactive domain 1B (JARID1B) (also known as KDM5B and PLU1) is overexpressed in breast cancer and is a potential target for breast cancer treatment. To investigate the in vivo function of JARID1B, we developed Jarid1b−/− mice and characterized their phenotypes in detail. Unlike previously reported Jarid1b−/− strains, the majority of these Jarid1b−/− mice were viable beyond embryonic and neonatal stages. This allowed us to further examine phenotypes associated with the loss of JARID1B in pubertal development and pregnancy. These Jarid1b−/− mice exhibited decreased body weight, premature mortality, decreased female fertility, and delayed mammary gland development. Related to these phenotypes, JARID1B loss decreased serum estrogen level and reduced mammary epithelial cell proliferation in early puberty. In mammary epithelial cells, JARID1B loss diminished the expression of key regulators for mammary morphogenesis and luminal lineage specification, including FOXA1 and estrogen receptor α. Mechanistically, JARID1B was required for GATA3 recruitment to the Foxa1 promoter to activate Foxa1 expression. These results indicate that JARID1B positively regulates mammary ductal development through both extrinsic and cell-autonomous mechanisms. 相似文献
999.