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Sea cucumber is widely consumed as a putative functional food. It contains many biologically-active substances, but only limited research on its properties in vivo has been done. The effects of different meals containing Isostichopus badionotus, a sea cucumber from southeast Mexico, on growth performance and body lipid profile in young rats were analyzed. Sea cucumber body wall was either lyophilized, cooked (100 °C, 1 h in water) and lyophilized, or oven-dried (70 °C for 12 h). It was then ground and incorporated into cholesterol-containing diets. I. badionotus meals supported growth and improved lipid profile in rats. In particular, serum cholesterol, low density lipoproteins, triglycerides concentration and atherogenic index values were greatly reduced by some I. badionotus containing diets. Liver total lipids, triglycerides and cholesterol were also reduced. Cooking or heat-treatment of the meals lowered but did not abolish their hypolipidemic potency. Gene expression analysis of several key genes involved in cholesterol and lipid metabolism in liver showed that diets containing I. badionotus repressed the induction of key genes associated with dyslipidemia exerted by cholesterol supplementation. Consumption of I. badionotus from the Yucatan Peninsula is beneficial for dyslipidemia, although biological effect is clearly dependent on preparation method.  相似文献   
283.
BioMetals - Aqueous glutathione selenium nano-incorporation (GSH-SeN-Inco) was prepared by gamma radiation in presence of microbial glutathione (GSH) and selenium dioxide. The novel prepared...  相似文献   
284.
Protein-RNA interactions are central to essential cellular processes such as protein synthesis and regulation of gene expression and play roles in human infectious and genetic diseases. Reliable identification of protein-RNA interfaces is critical for understanding the structural bases and functional implications of such interactions and for developing effective approaches to rational drug design. Sequence-based computational methods offer a viable, cost-effective way to identify putative RNA-binding residues in RNA-binding proteins. Here we report two novel approaches: (i) HomPRIP, a sequence homology-based method for predicting RNA-binding sites in proteins; (ii) RNABindRPlus, a new method that combines predictions from HomPRIP with those from an optimized Support Vector Machine (SVM) classifier trained on a benchmark dataset of 198 RNA-binding proteins. Although highly reliable, HomPRIP cannot make predictions for the unaligned parts of query proteins and its coverage is limited by the availability of close sequence homologs of the query protein with experimentally determined RNA-binding sites. RNABindRPlus overcomes these limitations. We compared the performance of HomPRIP and RNABindRPlus with that of several state-of-the-art predictors on two test sets, RB44 and RB111. On a subset of proteins for which homologs with experimentally determined interfaces could be reliably identified, HomPRIP outperformed all other methods achieving an MCC of 0.63 on RB44 and 0.83 on RB111. RNABindRPlus was able to predict RNA-binding residues of all proteins in both test sets, achieving an MCC of 0.55 and 0.37, respectively, and outperforming all other methods, including those that make use of structure-derived features of proteins. More importantly, RNABindRPlus outperforms all other methods for any choice of tradeoff between precision and recall. An important advantage of both HomPRIP and RNABindRPlus is that they rely on readily available sequence and sequence-derived features of RNA-binding proteins. A webserver implementation of both methods is freely available at http://einstein.cs.iastate.edu/RNABindRPlus/.  相似文献   
285.
One of the major breakthroughs in neuroscience is the emerging understanding of how signals from the external environment are extracted and represented in the primary sensory cortices of the mammalian brain. The operational principles of the rest of the cortex, however, have essentially remained in the dark. The discovery of grid cells, and their functional organization, opens the door to some of the first insights into the workings of the association cortices, at a stage of neural processing where firing properties are shaped not primarily by the nature of incoming sensory signals but rather by internal self-organizing principles. Grid cells are place-modulated neurons whose firing locations define a periodic triangular array overlaid on the entire space available to a moving animal. The unclouded firing pattern of these cells is rare within the association cortices. In this paper, we shall review recent advances in our understanding of the mechanisms of grid-cell formation which suggest that the pattern originates by competitive network interactions, and we shall relate these ideas to new insights regarding the organization of grid cells into functionally segregated modules.  相似文献   
286.
This comprehensive article explores the complex field of glioma treatment, with a focus on the important roles of non-coding RNAsRNAs (ncRNAs) and exosomes, as well as the potential synergies of immunotherapy. The investigation begins by examining the various functions of ncRNAs and their involvement in glioma pathogenesis, progression, and as potential diagnostic biomarkers. Special attention is given to exosomes as carriers of ncRNAs and their intricate dynamics within the tumor microenvironment. The exploration extends to immunotherapy methods, analyzing their mechanisms and clinical implications in the treatment of glioma. By synthesizing these components, the article aims to provide a comprehensive understanding of how ncRNAs, exosomes, and immunotherapy interact, offering valuable insights into the evolving landscape of glioma research and therapeutic strategies.  相似文献   
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Uredinia and urediniospores of six Puccinia species growing on Poaceae in southwestern Saudi Arabia were morphologically compared by light and scanning electron microscopy (SEM). Puccinia cenchri, P. fragosoana and P. isiacae were recorded for the first time in Saudi Arabia. Many differences between uredinia and urediniospores of studied Puccinia species were recorded. These differences are not related to host plant but may be due to the species of Puccinia itself. Observations by SEM led to more information in distinguishing between these Puccinia species particularly the presence of paraphyses and density and length of spines.  相似文献   
289.
Molecular Biology Reports - Rectal cancer is a common malignancy with a relatively poor prognosis. We assessed the possible prognostic and predictive role(s) of circulating tumor cells (CTCs) and...  相似文献   
290.
A highly specific microarray method for point mutation detection   总被引:1,自引:0,他引:1  
Improvements of microarray techniques for genotyping purposes have focused on increasing the reliability of this method. Here we report the development of a genotyping method where a microarray was spotted with stemloop probes, especially designed to optimize the hybridization specificity of complementary DNA sequences. This accurate method was used to screen for four common disease-causing mutations involved in a neurological disorder called Charcot-Marie-Tooth disease (CMT). Healthy individuals' and patients' DNA were amplified and labeled by PCR and hybridized on microarray. The spot signal intensities were 81 to 408 times greater for perfect compared with mismatched target sequences, differing by only one nucleotide (discrimination ratio) for healthy individual "homozygous" DNA. On the other hand, "heterozygous" mutant DNA samples gave rise to signal intensity ratios close to 1, as expected. The genotypes obtained by this method were perfectly consistent with those determined by direct PCR sequencing. Cross-hybridization rates were very low, resulting in further multiplexing improvements. In this study, we also demonstrated the feasibility of real-time hybridization detection of labeled synthetic oligonucleotides with concentrations as low as 2.5 nM.  相似文献   
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