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991.
Septin14 is an important spermatogenesis related gene involved in the pathogenesis of male infertility that has not been well studied. Here, full-length Septin14 cDNA of the Banna mini-pig inbred line (BMI) was cloned using the RACE method and expressed in pig kidney epithelial cells (PK15) and E. coli Rosetta (DE3) cells. Septin14 expression was identified in somatic tissues and testis in different developmental stages. The pig Septin14 CDS is 1,299 bp long, and encodes a peptide (or protein) of 432 amino acids (MW=50.4 kDa). Phylogenetic analysis indicated that pig Septin14 was highly evolutionarily conserved. Subcellular localization of GFP-tagged Septin14 fusion protein revealed that Septin14 was distributed throughout the testicular cells. Among 34 pig tissues, Septin14 mRNA was found specifically in testis and seminal vesicle. In six different postnatal developmental stages, the testicular level of Septin14 mRNA was barely detectable on day 2, while the highest level occurred on day 75. The spatiotemporal expression profile of Septin14, reported herein for the first time in pig, indicated that Septin14 might be involved in the division, development and apoptosis of germ cells. Furthermore, using a pET prokaryotic expression system, we expressed and isolated recombinant 67.9 kDa Septin14 protein. 相似文献
992.
993.
Seasonal effects of intercropping on tree water use strategies in semiarid plantations: Evidence from natural and labelling stable isotopes 总被引:1,自引:0,他引:1
Plant and Soil - Intercropping in plantations can improve ecosystem services, but its potential effects on trees’ water use and production are concerns due to increases in water scarcity... 相似文献
994.
Gao L Tao D Shan Y Liang Z Zhang L Huo Y Zhang Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(32):3370-3374
Deer antlers mature rapidly in 60 days, and subsequently shed in 5 days with rapid ossification. During this procedure, the function of deer antlers changes significantly. Therefore, the profiling of antler proteome is helpful to discover important growing and shedding regulation proteins, which might be of great significance for studying development and regeneration. In this study, a parallel protein extraction strategy was developed to extract proteins from antlers of red deer with five different lysis solutions, followed by shotgun proteomic analysis by microflow reversed-phase liquid chromatography/electrospray ionization/tandem mass spectrometry (μRPLC-ESI-MS/MS) with a 30 cm-long serially coupled microcolumn. Our experimental results showed that the identified proteins extracted by five kinds of lysis solution were complementary to each other. In total, 416 unique proteins were identified, with relative molecular masses from 2000 to 600,000, and isoelectric points from 3.84 to 11.57. All these results demonstrate that the combination of parallel protein extraction strategy and μRPLC-ESI-MS/MS analysis with serially coupled long microcolumns might be of great significance for comprehensive proteomic research of deer antler. 相似文献
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996.
997.
Effects of starvation on larval growth, survival, and metamorphosis of Manila clam Ruditapes philippinarum
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The effects of starvation on larval growth, survival, and metamorphosis of Manila clam Ruditapes philippinarum at the temperature of 19.6–21.6 °C, the salinity of 34‰ and pH of 8.0 were investigated from May 18 to July 18, 2006. In this study, the early, middle and late umbo-veliger larvae with the shell lengths of 100, 140, and 190 μm were subject to temporary food deprivation for up to 4.5, 20, and 25d at 0.5, 4, 5d intervals, followed by refeeding for the remaining of a 24, 20, 25d period, respectively. The results suggested that the larvae should have shown considerable tolerance to starvation due to their endogenous and exterior nutrition material, for larvae and time to the point-of-no-return (PNR: the threshold point during starvation after which larvae could no longer metamorphose even if food is provided) were calculated to be 4.25, 17.54, and 22.17d. As the starvation period prolonged, the mean shell length of larvae starved got close to constants at 1.5, 4, and 15d after starvation, which were different for larvae at different stages when starvation began, survival of larvae decreased, and was lower in treatments starved earlier in development than those starved later, for the early, middle and late umbo-veliger larvae, after 4.5, 20 and 25d of starvation period, few larvaes were alive. After starvation period, the alive larvaes were able to metamorphose and had a capability of compensatory growth when refeeding was given. Starvation not only affected metamorphosis rate, but also caused the delay in the time to metamorphosis and the decrease in the metamorphosed sizes. For example, for the continuously-fed larvae, duration to metamorphosis was 20.7d, for larvae with a size of 100-μm starved for up to 4d, larvae with a size of 140-μm starved for up to 16d, larvae with a size of 190-μm starved for up to 20d, duration to metamorphosis were 29.7, 31.7, and 37.7d, the delay in duration to metamorphosis were 9, 11, and 17d, respectively. Furthermore, importance of nutrition material for maintaining larval survival during starvation and the compensatory growth on larvae at the same feeding time were discussed. 相似文献
998.
David J. M. Lewis Zhiming Huo Susan Barnett Ingrid Kromann Rafaela Giemza Eva Galiza Maria Woodrow Birgit Thierry-Carstensen Peter Andersen Deborah Novicki Giuseppe Del Giudice Rino Rappuoli 《PloS one》2009,4(9)
Background
An association was previously established between facial nerve paralysis (Bell''s palsy) and intranasal administration of an inactivated influenza virosome vaccine containing an enzymatically active Escherichia coli Heat Labile Toxin (LT) adjuvant. The individual component(s) responsible for paralysis were not identified, and the vaccine was withdrawn.Methodology/Principal Findings
Subjects participating in two contemporaneous non-randomized Phase 1 clinical trials of nasal subunit vaccines against Human Immunodeficiency Virus and tuberculosis, both of which employed an enzymatically inactive non-toxic mutant LT adjuvant (LTK63), underwent active follow-up for adverse events using diary-cards and clinical examination. Two healthy subjects experienced transient peripheral facial nerve palsies 44 and 60 days after passive nasal instillation of LTK63, possibly a result of retrograde axonal transport after neuronal ganglioside binding or an inflammatory immune response, but without exaggerated immune responses to LTK63.Conclusions/Significance
While the unique anatomical predisposition of the facial nerve to compression suggests nasal delivery of neuronal-binding LT–derived adjuvants is inadvisable, their continued investigation as topical or mucosal adjuvants and antigens appears warranted on the basis of longstanding safety via oral, percutaneous, and other mucosal routes. 相似文献999.
A competitive time-resolved fluoroimmunoassay (TR-FIA) was developed for the determination of diethylstilbestrol (DES) residues in chicken liver. Prior to analysis, the residues were extracted from chicken liver with acetonitrile. The assay could be used in a quantitative or qualitative mode. The limit of detection (LOD) was determined to be 0.05 ngg(-1), and the limit of quantification (LOQ) was less than 0.18 ngg(-1). The intraassay variations were less than 10%, and the interassay variations were from 9.8 to 12.7%. The mean recoveries established at six concentration levels varied from 84.3 to 109.6%, and the coefficients of variation were from 8.3 to 12.4%. The results obtained by the TR-FIA and enzyme-linked immunosorbent assay (ELISA) showed a good correlation. The established TR-FIA was validated for the determination of incurred chicken liver and was confirmed by liquid chromatography and tandem mass spectrometry (LC-MS/MS). This proposed technique could be applied to routine residue analysis. 相似文献
1000.
The sequence-dependent unfolding pathway plays a critical role in the amyloidogenicity of transthyretin 总被引:2,自引:0,他引:2
Human transthyretin (TTR) is an amyloidogenic protein whose aggregation is associated with several types of amyloid diseases. The following mechanism of TTR amyloid formation has been proposed. TTR tetramer at first dissociates into native monomers, which is the rate-limiting step in fibril formation. The monomeric species then partially unfold to form amyloidogenic intermediates that subsequently undergo a downhill self-assembly process. The amyloid deposit can be facilitated by disease-associated point mutations. However, only subtle structural differences were observed between the crystal structures of the wild type and the disease-associated variants. To investigate how single-point mutations influence the effective energy landscapes of TTR monomers, molecular dynamics (MD) simulations were performed on wild-type TTR and two pathogenic variants. Principal coordinate analysis on MD-generated ensembles has revealed multiple unfolding pathways for each protein. Amyloidogenic intermediates with the dislocated C strand-loop-D strand motif were observed only on the unfolding pathways of V30M and L55P variants and not for wild-type TTR. Our study suggests that the sequence-dependent unfolding pathway plays a crucial role in the amyloidogenicity of TTR. Analyses of side chain concerted motions indicate that pathogenic mutations on "edge strands" disrupt the delicate side chain correlated motions, which in turn may alter the sequence of unfolding events. 相似文献