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Rotavirus (RV) is the main etiological agent of severe gastroenteritis in infants, and vaccination seems the most effective way to control the disease. Recombinant rotavirus-like particles composed of the viral protein 6 (VP6) and VP2 (2/6-VLPs) have been reported to induce protective immunity in mice when administered by the intranasal (i.n.) route. In this study, we show that administration of 2/6-VLPs by the intrarectal (i.r.) route together with either cholera toxin (CT) or a CpG-containing oligodeoxynucleotide as the adjuvant protects adult mice against RV infection. Moreover, when CT is used, RV shedding in animals immunized by the i.r. route is even reduced in comparison with that in animals immunized by the i.n. route. Humoral and cellular immune responses induced by these immunization protocols were analyzed. We found that although i.r. immunization with 2/6-VLPs induces lower RV-specific immunoglobulin G (IgG) and IgA levels in serum, intestinal anti-RV IgA production is higher in mice immunized by the i.r. route. Cellular immune response has been evaluated by measuring cytokine production by spleen and Peyer's patch cells (PPs) after ex vivo restimulation with RV. Mice immunized by the i.n. and i.r. routes display higher gamma interferon production in spleen and PPs, respectively. In conclusion, we demonstrate that i.r. immunization with 2/6-VLPs protects against RV infection in mice and is more efficient than i.n. immunization in inducing an anti-RV immune response in intestinal mucosa.  相似文献   
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The main characters of the stalked crinoids of the family Pentacrinitidae attributed to the genus Teliocrinus are re‐evaluated from a quantitative study of phenotype variation, new observations on arm and stalk articulations, and observation of ontogenetic trends. All of the specimens collected in the northern Indian Ocean belong to the same species, i.e. Teliocrinus springeri (Clark, 1909). However, two phenotypes living at different depths remain valid as subspecies: Teliocrinus springeri springeri (Clark, 1909) and Teliocrinus springeri liliaceus (Clark, 1909). Teliocrinus shares several ontogenetic trends with Endoxocrinus, especially in nonfunctional brachial articulations and stalk symplexies. Its assignment to the Diplocrininae is confirmed. A discussion of its affinities with pentacrinid fossil genera in which the crown is well preserved suggests that Diplocrininae could have first appeared during the Lower Cretaceous. A shortening of brachitaxes and a paedomorphic trend of stalk symplexies are the main other evolutionary traits. Nonfunctional articulations are frequently found at the paedomorphic pole of the heterochronic gradient, without clear derived characters. Classification of pentacrinids mainly based on such symplesiomorphy or paedomorphic characters must be definitively abandoned. However, in post‐Palaeozoic stalked crinoids the scarcity of well‐preserved fossils, the high frequency of paedomorphy, and convergent adaptive characters makes phylogenetic reconstruction only based on morphological characters very difficult and speculative. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 22–39.  相似文献   
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The stability of tenuazonic acid solution at different temperatures and storage times was studied using methanol, methanol-water (8:2 v/v), benzene and benzene-acetonitrile (98:2 v/v) as solvents. Solutions were analysed by a spectrometric method TeA U.V.-spectrum was recorded. Results indicated that the optimum temperature for long-time storage period of tenuazonic acid solution in any solvent assayed is -20°C. Benzene and benzene-acetonitrile (98:2 v/v) could be advised to make tenuazonic acid solution which will be stored less than 2 months at 4°C. Methanol and methanolwater (8:2 v/v) are not recommended because a low stability of TeA solution in this solvents.  相似文献   
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AIMS: The BiodivYsio trade mark stent (Biocompatibles Ltd, Farnham, UK) is coated with a phosphorylcholine (PC)-containing copolymer to confer biocompatibility. The SOPHOS (Study Of PHosphorylcholine coating On Stents) study was designed to assess the safety and efficacy of this novel coronary stent and by indirect comparison to indicate equivalence with other formal stent studies. METHODS AND RESULTS: Patients with angina and a single short (#x2A7F;12 mm) de novo lesion in a native coronary artery of >/=2.75 mm diameter were included. A total of 425 patients were allocated in 24 centers. Clinical data were collected at one-, six- and nine-month follow-up. Angiography was performed before and after the stent implantation. In addition, in the first 200 patients (SOPHOS A) angiography was routinely performed at six months. The following 225 patients (SOPHOS B) were merely followed up clinically. The primary end-point of the study, the six-month MACE-rate (MACE = Major Adverse Cardiac Events) was 13.4% (two cardiac death; five Q-wave/nine non-Q-wave myocardial infarctions (MI); nine CABG and 32 target lesion revascularization (TLR), which is similar to the calculated 15% MACE-rate in comparable reference studies. Secondary end-points included among others restenosis at six months in the SOPHOS A population. The target vessel diameter was 2.98 +/- 0.48 mm. Minimal lumen diameter pre/post procedure and at follow-up was 1.00 +/- 0.32, 2.69 +/- 0.37, 1.91 +/- 0.71 mm, respectively. The binary restenosis rate (>/=50% diameter stenosis at follow-up) was 17.7%. CONCLUSION: The coronary BiodivYsio stent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with stable or unstable angina pectoris. Clinical and angiographic results are in the statistical range of equivalence with comparable studies with other current stents.  相似文献   
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Trans-splicing is an unusual process in which two separate RNA strands are spliced together to yield a mature mRNA. We present a novel computational approach which has an overall accuracy of 82% and can predict 92% of known trans-splicing sites. We have applied our method to chromosomes 1 and 3 of Leishmania major, with high-confidence predictions for 85% and 88% of annotated genes respectively. We suggest some extensions of our method to other systems.  相似文献   
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This investigation examined the exposure of Egyptian infants to Aflatoxin M1 (AfM1) and of lactating mothers to Aflatoxin B1, using AfM1 in human milk as a biomarker for exposure to AfB1. The presence of ochratoxin A (OA) in human milk was also investigated to determine the levels of infants exposure to OA from human milk. The results indicated that AfM1 was found in 66 (55 %) of 120 human milk samples with a mean of 0.3 ± 0.53 ng/mL (range 0.02 to 2.09 ng/mL). OA was found in 43 (35.8 %) of 120 human milk samples with a mean of 21.1 ± 13.7 ng/mL (range 5.07 to 45.01 ng/mL), which will cause a daily intake of OA from human milk exceeding the suggested tolerable dose of 5 ng/kg-1 of OA body weight. On the other side AfM1 was found in 25 % of blood samples (5 out of 20 samples), at a mean of 1.18 ng/mL, but it was detected only in one urine sample (1 out of 20 samples). OA was detected only in 2 out of 13 blood samples (15.4 %) with an average 3.67 ng/mL. Whereas OA was not detected in all analyzed urine samples.  相似文献   
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