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We report the detection and identification of Cryptosporidium and Giardia from 1 of 3 species of pinnipeds. Fecal samples were collected from Pacific harbor seal (Phoca vitulina richardsi), northern elephant seal (Mirounga angustirostris), and California sea lion (Zalophus californianus) in the northern California coastal area. By means of fluorescently labeled monoclonal antibodies, Cryptosporidium oocysts were detected in 3 samples from California sea lions, 1 of which also contained Giardia cysts. Oocysts of Cryptosporidium and cysts of Giardia were morphologically indistinguishable from oocysts of C. parvum and cysts of G. duodenalis from other animal origins. Oocysts and cysts were then purified using immunomagnetic separation techniques and identified by polymerase chain reaction (PCR), from which species-specific products were obtained. Sequence analysis revealed that the 452-bp and 358-bp PCR products of Cryptosporidium isolated from California sea lion had identities of 98% with sequences of their template fragments of C. parvum obtained from infected calves. Based on morphological, immunological, and genetic characterization, the isolates were identified as C. parvum and G. duodenalis, respectively. The findings suggested that California sea lions could serve as reservoirs in the environmental transmission of Cryptosporidium and Giardia. 相似文献
133.
Chunmei Qi Liangrong Deng Dongye Li Weiheng Wu Lei Gong Yong Li Qingdui Zhang Tao Zhang Chao Zhang Yu Zhang 《PloS one》2015,10(5)
BackgroundRupture of an atherosclerotic plaque is the primary cause of acute cardiovascular and cerebrovascular syndromes. Early and non-invasive detection of vulnerable atherosclerotic plaques (VP) would be significant in preventing some aspects of these syndromes. As a new contrast agent, dimercaptosuccinic acid (DMSA) modified ultra-small super paramagnetic iron oxide (USPIO) was synthesized and used to identify VP and rupture plaque by magnetic resonance imaging (MRI).MethodsAtherosclerosis was induced in male New Zealand White rabbits by feeding a high cholesterol diet (n = 30). Group A with atherosclerosis plaque (n = 10) were controls. VP was established in groups B (n = 10) and C (n = 10) using balloon-induced endothelial injury of the abdominal aorta. Adenovirus-carrying p53 genes were injected into the aortic segments rich in plaques after 8 weeks. Group C was treated with atorvastatin for 8 weeks. Sixteen weeks later, all rabbits underwent pharmacological triggering, and imaging were taken daily for 5 d after DMSA-USPIO infusion. At the first day and before being killed, serum MMP-9, sCD40L, and other lipid indicators were measured.ResultsDMSA-USPIO particles accumulated in VP and rupture plaques. Rupture plaques appeared as areas of hyper-intensity on DMSA-USPIO enhanced MRI, especially T2*-weighted sequences, with a signal strength peaking at 96 h. The group given atorvastatin showed few DMSA-USPIO particles and had lower levels of serum indicators. MMP-9 and sCD40L levels in group B were significantly higher than in the other 2 groups (P <0.05).ConclusionAfter successfully establishing a VP model in rabbits, DMSA-USPIO was used to enhance MRI for clear identification of plaque inflammation and rupture. Rupture plaques were detectable in this way probably due to an activating inflammatory process. Atorvastatin reduced the inflammatory response and stabilizing VP possibly by decreasing MMP-9 and sCD40L levels. 相似文献
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通过克隆海州香薷Actin基因片段并分析其组织表达,为研究海州香薷重金属抗性相关基因的表达调控奠定基础。根据Gen Bank中其他植物Actin基因保守序列设计兼并引物,以海州香薷根总RNA为模板,利用RT-PCR技术分离得到Actin基因片段。序列分析结果表明,海州香薷Actin基因片段长576 bp,编码192个氨基酸,与其他植物同源基因的氨基酸序列相似性为84%-97%,所克隆的序列为Actin基因的同源片段,将其命名为Eh ACT,在Gen Bank中提交序列,获得登录号AGT37260。半定量RT-PCR分析结果表明,Eh ACT在海州香薷的根、茎和叶中表达相对稳定,初步表明其可作为研究海州香薷基因表达的内参基因。 相似文献
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Jiaojiao Deng Xiaoliang Yu Xianying Qin Dong Zhou Lihan Zhang Huan Duan Feiyu Kang Baohua Li Guoxiu Wang 《Liver Transplantation》2019,9(14)
Transition metal oxides hold great promise as high‐energy anodes in next‐generation lithium‐ion batteries. However, owing to the inherent limitations of low electronic/ionic conductivities and dramatic volume change during charge/discharge, it is still challenging to fabricate practically viable compacted and thick TMO anodes with satisfactory electrochemical performance. Herein, with mesoporous cobalt–boride nanoflakes serving as multifunctional bridges in ZnCo2O4 micro‐/nanospheres, a compacted ZnCo2O4/Co–B hybrid structure is constructed. Co–B nanoflakes not only bridge ZnCo2O4 nanoparticles and function as anchors for ZnCo2O4 micro‐/nanospheres to suppress the severe volume fluctuation, they also work as effective electron conduction bridges to promote fast electron transportation. More importantly, they serve as Li+ transfer bridges to provide significantly boosted Li+ diffusivity, evidenced from both experimental kinetics analysis and density functional theory calculations. The mesopores within Co–B nanoflakes help overcome the large Li+ diffusion barriers across 2D interfaces. As a result, the ZnCo2O4/Co–B electrode delivers high gravimetric/volumetric/areal capacities of 995 mAh g?1/1450 mAh cm?3/5.10 mAh cm?2, respectively, with robust rate capability and long‐term cyclability. The distinct interfacial design strategy provides a new direction for designing compacted conversion‐type anodes with superior lithium storage kinetics and stability for practical applications. 相似文献
140.
Xiao‐Li Wang Hua‐Fei Deng Ting Li Shu‐Ying Miao Zi‐Hui Xiao Mei‐Dong Liu Ke Liu Xian‐Zhong Xiao 《Journal of biochemical and molecular toxicology》2019,33(4)
Platelet activation contributes to organs failure in inflammation and plays an important role in endotoxemia. Clopidogrel inhibits platelet aggregation and activation. However, the role of clopidogrel in modulating inflammatory progression of endotoxemia remains largely unexplored. Therefore, we investigated the role of clopidogrel on the activation of platelet and leukocytes in lipopolysaccharide (LPS)‐induced inflammation in mice. Animals were treated with clopidogrel or vehicle before LPS induction. The expression of neutrophil‐platelet aggregates and platelet activation and tissue factor was determined. Immunofluorescence was used to analyze platelet‐leukocyte interactions and tissue factor (TF) expression on leukocytes. Clopidogrel pretreatment markedly decreased lung damage, inhibited platelet‐neutrophil aggregates and TF expression. In addition, clopidogrel reduced thrombocytopenia and affected the number of circulating white blood cell in endotoxemia mice. Moreover, clopidogrel also reduced platelet shedding of CD40L and CD62P in endotoxemic mice. Taken together, clopidogrel played an important role through reducing platelet activation and inflammatory process in endotoxemia. 相似文献