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91.
The common cold is most often a result of human rhinovirus (HRV) infection. Common cold symptoms including rhinorrhea and nasal obstruction frequently occur during HRV infection of the upper respiratory tract. Conversely, HRV may also infect the epithelial cells of the lower respiratory tract. Symptom severity associated with HRV infection ranges from mild to potentially serious depending on a person’s susceptibility and pre-existing condition, such as chronic obstructive pulmonary disease. An over active host immune response is believed to be the primary contributor to HRV pathogenesis. Enhanced activity of various host cell cytokines and granulocytes mediate specific cellular pathways inducing many of the symptoms associated with HRV infection. There are over 100 serotypes of HRV which can be further categorized based on the specific characteristics of each type. The two main categories of HRV consist of the major and minor groups. The unique host cell receptor is the distinguishing factor between these two groups. Yet, these viruses may also differ in mechanism of infection and replication. Due to the high frequency of hospital and clinical visits and the corresponding economic burden, novel therapies are of interest. Several different treatment options varying from herbal remedies to anti-viral drugs have been studied. However, the vast number of HRV serotypes complicates the progress of developing a universal treatment for attenuating HRV infection. 相似文献
92.
Genome-wide analysis of gene-gene interactions has been recognized as a powerful avenue to identify the missing genetic components that can not be detected by using current single-point association analysis. Recently, several model-free methods (e.g. the commonly used information based metrics and several logistic regression-based metrics) were developed for detecting non-linear dependence between genetic loci, but they are potentially at the risk of inflated false positive error, in particular when the main effects at one or both loci are salient. In this study, we proposed two conditional entropy-based metrics to challenge this limitation. Extensive simulations demonstrated that the two proposed metrics, provided the disease is rare, could maintain consistently correct false positive rate. In the scenarios for a common disease, our proposed metrics achieved better or comparable control of false positive error, compared to four previously proposed model-free metrics. In terms of power, our methods outperformed several competing metrics in a range of common disease models. Furthermore, in real data analyses, both metrics succeeded in detecting interactions and were competitive with the originally reported results or the logistic regression approaches. In conclusion, the proposed conditional entropy-based metrics are promising as alternatives to current model-based approaches for detecting genuine epistatic effects. 相似文献
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Xianyang Fang Jinbu Wang Ina P. O’Carroll Michelle Mitchell Xiaobing Zuo Yi Wang Ping Yu Yu Liu Jason W. Rausch Marzena A. Dyba Jørgen Kjems Charles D. Schwieters Soenke Seifert Randall E. Winans Norman R. Watts Stephen J. Stahl Paul T. Wingfield R. Andrew Byrd Stuart F.J. Le Grice Alan Rein Yun-Xing Wang 《Cell》2013
98.
Shuangshuang Yin Wenyuan Gao Yuyong Liang Juan Wang Hui Liu Changlong Wei Beimei Zuo 《Acta Physiologiae Plantarum》2013,35(5):1579-1585
In this study, we investigated the induction of Pseudostellaria heterophylla adventitious root and the effects of sucrose concentration and phosphate source on biomass increase and metabolites accumulation. These roots were initially cultured in Murashige and Skoog medium for 4 weeks. IBA 3.0 mg L?1 proved to be the best auxin for inducing adventitious roots and the frequency of adventitious roots induced from roots (100 %) was higher than that from leaves (78 %) and stems (27 %). The medium with 4 % sucrose resulted in the optimum biomass i.e. 1.04 g/flask DW, and the content of saponin and polysaccharides reached the peak i.e. 0.676 and 24.4 %, respectively. With regards to phosphate source, 1.25 mM phosphate concentration was more favorable for biomass of roots (0.87 g/flask of DW), whereas the optimum saponin (0.74 %) and polysaccharides (22.09 %) were achieved with 2.5 mM phosphate. However, the saponin content at 2.5 mM phosphate did not show significant difference from the saponin content at 0.625 mM (0.69 %) or 3.75 mM phosphate (0.69 %). 相似文献
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Li Zuo Ekaterini Iordanou Rachana R. Chandran Lan Jiang 《Cell and tissue research》2013,354(2):343-354
The size of various tubes within tubular organs such as the lung, vascular system and kidney must be finely tuned for the optimal delivery of gases, nutrients, waste and cells within the entire organism. Aberrant tube sizes lead to devastating human illnesses, such as polycystic kidney disease, fibrocystic breast disease, pancreatic cystic neoplasm and thyroid nodules. However, the underlying mechanisms that are responsible for tube-size regulation have yet to be fully understood. Therefore, no effective treatments are available for disorders caused by tube-size defects. Recently, the Drosophila tracheal system has emerged as an excellent in vivo model to explore the fundamental mechanisms of tube-size regulation. Here, we discuss the role of the apical luminal matrix, cell polarity and signaling pathways in regulating tube size in Drosophila trachea. Previous studies of the Drosophila tracheal system have provided general insights into epithelial tube morphogenesis. Mechanisms that regulate tube size in Drosophila trachea could be well conserved in mammalian tubular organs. This knowledge should greatly aid our understanding of tubular organogenesis in vertebrates and potentially lead to new avenues for the treatment of human disease caused by tube-size defects. 相似文献