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71.
The cholinergic antiinflammatory pathway (CAP), which terminates in the spleen, attenuates postoperative cognitive decline (PCD) in rodents. Surgical patients with metabolic syndrome exhibit exaggerated and persistent PCD that is reproduced in postoperative rats selectively bred for easy fatigability and that contain all features of metabolic syndrome (low-capacity runners [LCRs]). We compared the CAP and lipoxin A4 (LXA4), another inflammation-resolving pathway in LCR, with its counterpart high-capacity runner (HCR) rats. Isoflurane-anesthetized LCR and HCR rats either underwent aseptic trauma involving tibial fracture (surgery) or not (sham). At postoperative d 3 (POD3), compared with HCR, LCR rats exhibited significantly exaggerated PCD (trace fear conditioning freezing time 43% versus 57%). Separate cohorts were killed at POD3 to collect plasma for LXA4 and to isolate splenic mononuclear cells (MNCs) to analyze CAP signaling, regulatory T cells (Tregs) and M2 macrophages (M2 Mφ). Under lipopolysaccharide (LPS) stimulation, tumor necrosis factor (TNF)-α produced by splenic MNCs was 117% higher in LCR sham and 52% higher in LCR surgery compared with HCR sham and surgery rats; LPS-stimulated TNF-α production could not be inhibited by an α7 nicotinic acetylcholine receptor agonist, whereas inhibition by the β2 adrenergic agonist, salmeterol, was significantly less (−35%) than that obtained in HCR rats. Compared to HCR, sham and surgery LCR rats had reduced β2 adrenergic receptor–expressing T lymphocytes (59%, 44%), Tregs (47%, 54%) and M2 Mφ (45%, 39%); surgical LCR rats’ hippocampal M2 Mφ was 66% reduced, and plasma LXA4 was decreased by 120%. Rats with the metabolic syndrome have ineffective inflammation-resolving mechanisms that represent plausible reasons for the exaggerated and persistent PCD.  相似文献   
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The Afrotropical Mantispidae genera have previously been neglected and are poorly known. The genera are revised and redescribed. A new genus Afromantispa Snyman and Ohl is described with Afromantispa tenellacomb. n.as type species. Perlamantispa (Handschin, 1960) is synonymised with Sagittalata Handschin, 1959. The new combinations within the genus include Sagittalata austroafricacomb. n., Sagittalata bequaerticomb. n., Sagittalata dorsaliscomb. n., Sagittalata girardicomb. n., Sagittalata nubilacomb. n.,Sagittalata perlacomb. n.,Sagittalata pusillacomb. n., Sagittalata similatacomb. n., Sagittalata royicomb. n., Sagittalata tinctacomb. n. andSagittalata vasseicomb. n. An illustrated key to the genera Afromantispagen. n., Sagittalata Handschin, 1959, Mantispa Illiger, 1798, Cercomantispa Handschin, 1959, Rectinerva Handschin, 1959, Nampista Navás, 1914, and Pseudoclimaciella Handschin, 1960 is provided. The wing venation of Mantispidae is redescribed. Similarities between the genera are discussed. Subsequent studies will focus on revising the taxonomic status of species, which are not dealt with in this study.  相似文献   
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The design and operation of a manually operated multiple syringe inoculator was described. Either 9 or 21 inoculations of constant volume could be made simultaneously. Up to 100 plates could be inoculated in 15 min with excellent reproducibility. No contact occurred between the inoculating needles and the agar surface. Construction was simple and inexpensive, with minimal maintenance.  相似文献   
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Evaluation of Restoration Techniques for the Succulent Karoo, South Africa   总被引:1,自引:0,他引:1  
Abstract Possible constraints on the passive recovery of bare areas in the Karoo, a semiarid region in South Africa, include inadequate supply of seed, availability of suitable microsites for plant establishment, altered soil properties, and the truncation of key soil biotic processes. Here we investigate the possibility of initiating the restoration of bare areas by soil surface treatments with gypsum (CaSO4) and/or organic mulch. We also apply an exogenous seed source to test the hypothesis that seed availability limits autogenic recovery. Both gypsum and mulch improved rain water infiltration, gypsum more so than mulch, and both treatments resulted in significantly higher numbers of reseeded seedlings compared with controls. Gypsum also improved the survival of the cohorts of seedlings of the larger seeded Tripteris sinuata. Tripteris showed the highest number of seedlings (maximum count of 150 seedlings/1,000 viable seeds sown) and surviving plants of the three reseeded species, which included two small‐seeded species, Ruschia spinosa and Chaetobromus dregeanus. Throughout the study period significantly higher plant volumes of naturally seeded annuals and perennials were recorded in the gypsum and/or mulch treatments compared with the controls. Germination and emergence of reseeded and naturally seeded plants appears to be determined by the availability of cool season (autumn to spring ) soil moisture, whereas follow‐up rainfall during this time is important for plant survival. Mulching of bare areas in the Succulent Karoo has the potential to re‐create vegetated areas that will further capture and conserve water, soil, and nutrients. Gypsum also showed positive results but might not be a cost‐effective option because of transport costs to these remote arid areas.  相似文献   
77.
Mis-priming associated with uncharacterised single nucleotide polymorphisms (SNPs) may lead to failure of PCR for genotyping. This is particularly troublesome in high-throughput SNP genotyping applications relying on multiplex PCR (2–40-plex) generating many short amplicons (80–120 bp) of similar size, an approach best suited for whole genome scans. However, if the target SNPs are clustered within a few target genes one option to ameliorate this is to increase the amplicon length, effectively reducing the potential for primer/template interactions and mis-priming. We tested this approach in a diverse population of 372 Eucalyptus pilularis individuals (π = 8.11 × 10−3, H e = 0.75) using a modified Sequenom iPLEX gold assay. Four candidate genes (MYB1, MYB2, CAD and CCR) were amplified in a single long range multiplex capture PCR generating 6 long amplicons ranging in size from 907 to 2,225 bp. This contrasts with the standard approach which would have required the amplification of 98 short amplicons in 4 multiplex reactions. These 6 long amplicons provided the assay template for 98 assays (87 SNP and 11 InDel) within the 4 candidate genes. Reaction results indicated that longer amplicons could provide a suitable template for genotyping assays, with 90.8% of assays functional and 84.3% of assays suitable for downstream analysis. Additional advantages of this approach were the capacity for troubleshooting using gel electrophoresis and savings of 94% in capture primer synthesis costs. This approach will have the greatest relevance for candidate gene approaches for association testing in uncharacterised populations of organisms with high sequence diversity.  相似文献   
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Gibberellin (GA) metabolism from GA12-aldehyde was studied in cell-free systems from 2-d-old germinating embryos of barley. [14C]- or [17-2H2]Gibberellins were used as substrates and all products were identified by combined gas chromatography-mass spectrometry. Stepwise analysis demonstrated the conversion of GA12-aldehyde via the 13-deoxy pathway to GA51 and via the 13-hydroxylation pathway to GA29, GA1 and GA8. In addition, GA3 was formed from GA20 via GA5. We conclude that the embryo is capable of producing gibberellins that can induce -amylase production in the aleurone layer. There was no evidence for 12- or 18-hydroxylation and GA4 was neither synthesised nor metabolised by the system. All metabolically obtained GAs, with the exception of GA3, were also found as endogenous components of the cell-free system in spite of ammonium-sulfate precipitation and desalting steps.Abbreviations GAn gibberellin An - GC-MS combined gas chromatography-mass spectrometry - HPLC high-performance liquid chromatography We thank Mrs. G. Bodtke and Mrs. B. Schattenberg for preparing the barley embryos and the Deutsche Forschungsgemeinschaft for supporting this work.  相似文献   
80.
The stay-green phenotype results from a naturally occurring mutation in which senescent leaves retain their chlorophyll and the associated apoprotein, LHCPII. Protection of this protein pool could deliver grass with enhanced protein content and could decrease the extent of protein degradation by plant proteases in the rumen. This would enhance the efficiency of protein utilization in livestock to the benefit of the environment. Field plots of stay-green and wild-type Lolium perenne were defoliated at intervals to simulate grazing. There were variations in foliar protein content and proteolysis throughout the year, but no significant differences between genotypes when material was analysed fresh or after it was cut and dried to simulate hay-making, which possibly induced senescence. In a subsequent experiment with stay-green and wild-type L temulentum, increased protein retention and decreased protein degradability were observed in stay-green leaves that were allowed to senescence naturally and extensively on the plant. That there is no difference between the two L. perenne genotypes suggests that as a field crop in grazed pastures the stay-green genotype would not confer a nutritional advantage in terms of protein degradability. It is possible that grazing promotes a high proportion of non-senescent to senescent leaf material within the sward and thus any advantage conferred by the stay-green phenotype would be effectively masked by an abundance of mature foliage. It is suggested that the stay-green trait would be of benefit in areas where agricultural practice permits extensive natural senescence to occur.  相似文献   
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