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191.
The orange-spotted grouper (Epinephelus coioides), a favorite marine food fish, is widely cultured in China and Southeast Asian countries. However, little is known about its acute phase response (APR) caused by viral diseases. Serum amyloid A (SAA) is a major acute phase protein (APP). In this study, a new SAA homologous (EcSAA) gene was cloned from grouper, E. coioides, by rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA sequence of SAA was 508 bp and contained a 363 bp open reading frame (ORF) coding for a protein of 121 aa. Similar to other fish known SAA genes, the EcSAA gene contained four exons and three introns. Quantitative real-time PCR analysis revealed that EcSAA mRNA is predominately expressed in liver and gill of grouper. Furthermore, the expression of EcSAA was differentially up-regulated in liver after infection with Staphyloccocus aureus, Vibrio vulnificus, Vibrio parahaemolyticus, Saccharomyces cerevisiae and Singapore grouper iridovirus (SGIV). Recombinant EcSAA (rEcSAA) was expressed in Escherichia BL21 (DE3) and purified for mouse anti-EcSAA serum preparation. The rEcSAA fusion protein was demonstrated to bind to all tested bacteria and yeast, and inhibit the replication of SGIV. Overexpression of EcSAA in grouper spleen (GS) cells could also inhibit the replication of SGIV. These results suggest that EcSAA may be an important molecule in the innate immunity of grouper. 相似文献
192.
皂苷类药物普遍分子量比较大,水溶性好,但不易透过细胞膜难以被人体吸收,因此口服制剂体内生物利用度较低.近年来对单体皂苷及总皂苷类药物制剂方面的研究越来越多,随着新型的给药系统和新辅料的出现,皂苷类药物在体内的生物利用度大大提高.本文主要介绍以单体皂苷或总皂苷活性部位为主药的制剂研究进展,以期为该类成分的进一步研究提供思路. 相似文献
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Soo Youn Kim Zheng-Yi Xu Kyungyoung Song Dae Heon Kim Hyangju Kang Ilka Reichardt Eun Ju Sohn Ji?í Friml Gerd Juergens Inhwan Hwang 《The Plant cell》2013,25(8):2970-2985
Fertilization in flowering plants requires the temporal and spatial coordination of many developmental processes, including pollen production, anther dehiscence, ovule production, and pollen tube elongation. However, it remains elusive as to how this coordination occurs during reproduction. Here, we present evidence that endocytosis, involving heterotetrameric adaptor protein complex 2 (AP-2), plays a crucial role in fertilization. An Arabidopsis thaliana mutant ap2m displays multiple defects in pollen production and viability, as well as elongation of staminal filaments and pollen tubes, all of which are pivotal processes needed for fertilization. Of these abnormalities, the defects in elongation of staminal filaments and pollen tubes were partially rescued by exogenous auxin. Moreover, DR5rev:GFP (for green fluorescent protein) expression was greatly reduced in filaments and anthers in ap2m mutant plants. At the cellular level, ap2m mutants displayed defects in both endocytosis of N-(3-triethylammonium-propyl)-4-(4-diethylaminophenylhexatrienyl) pyridinium dibromide, a lypophilic dye used as an endocytosis marker, and polar localization of auxin-efflux carrier PIN FORMED2 (PIN2) in the stamen filaments. Moreover, these defects were phenocopied by treatment with Tyrphostin A23, an inhibitor of endocytosis. Based on these results, we propose that AP-2–dependent endocytosis plays a crucial role in coordinating the multiple developmental aspects of male reproductive organs by modulating cellular auxin level through the regulation of the amount and polarity of PINs. 相似文献
195.
Jessica Fitzgibbon Martina Beck Ji Zhou Christine Faulkner Silke Robatzek Karl Oparka 《The Plant cell》2013,25(1):57-70
Plasmodesmata (PD) form tubular connections that function as intercellular communication channels. They are essential for transporting nutrients and for coordinating development. During cytokinesis, simple PDs are inserted into the developing cell plate, while during wall extension, more complex (branched) forms of PD are laid down. We show that complex PDs are derived from existing simple PDs in a pattern that is accelerated when leaves undergo the sink–source transition. Complex PDs are inserted initially at the three-way junctions between epidermal cells but develop most rapidly in the anisocytic complexes around stomata. For a quantitative analysis of complex PD formation, we established a high-throughput imaging platform and constructed PDQUANT, a custom algorithm that detected cell boundaries and PD numbers in different wall faces. For anticlinal walls, the number of complex PDs increased with increasing cell size, while for periclinal walls, the number of PDs decreased. Complex PD insertion was accelerated by up to threefold in response to salicylic acid treatment and challenges with mannitol. In a single 30-min run, we could derive data for up to 11k PDs from 3k epidermal cells. This facile approach opens the door to a large-scale analysis of the endogenous and exogenous factors that influence PD formation. 相似文献
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197.
Finds of fossil wood with bivalve wood borings (Teredolites clavatus and T. longissimus) occur in various facies and presumed sedimentary settings of the platform, shallow-marine Bohemian Crectaceous Basin. The basin comprises areas with sandy-dominated sediments, with marl and clay-dominated sediments, areas with predominat sandy-marly rocks, and finally areas dominated by calcareous nearshore sediments. Teredolites clavatus is common in fossil wood of sandstones, originating in beach or deltaic settings; marl and clay-dominated rock frequently bear wood fragments densely bored by Teredolites longissimus. When accompanied by evidence of marine environments as body fossils, glauconite or typical trace fossils, most of the wood fragments are bored. The presence/absence of borings in wood fragments can be considered the most reliable and easily useable criterion of distinction of marine settings in sandy sediments of the margin of the Bohemian Cretaceous Basin. 相似文献
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Cheng-Di Chiu You-Pen Chiu Cheng-Li Lin Hui-Ru Ji Chiung-Chyi Shen Hsu-Tung Lee 《Free radical research》2013,47(9):1010-1019
AbstractHyperglycaemia is associated with the poor outcome after intracerebral haemorrhage (ICH). Acetazolamide (AZA), a kind of carbonic anhydrogenase (CA) inhibitor, its effectiveness in ICH had been reported. However, the connections between AZA and ICH, especially in hyperglycaemia condition had never been defined. In this study, adult Sprague–Dawley rats were administered with vehicle or streptozotocin (STZ) to render them into normoglycaemic (NG) or hyperglycaemic (HG), respectively. Collagenase was then injected into the striatum. The NG or HG ICH rats treated with vehicle control or 5?mg/kg AZA (oral gavage) underwent haemorrhagic area assessments on the 1st, 4th, and 7th day after ICH. The coverage of pericytes was examined by immunohistochemistry. Reactive oxygen species (ROS) levels were assessed in mouse astrocyte cell line treated with vehicle or 20?μmol/L of AZA in culture media according to two different glucose concentrations. AZA reduced the haematoma size, improved neurobehavioral functions, suppressed astrocytic ROS production in vitro, and preserved cerebral pericytes coverage, which are even more remarkable in HG conditions. The present study indicates that AZA may alleviate some sequelae after ICH, especially in poorer prognostic HG rats through the suppression of astrocytic ROS production. 相似文献