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901.
An entomopathogenic, Gram-negative bacterium isolated from a female specimen of the fruit fly Drosophila melanogaster was taxonomically characterised. Strain L48(T) was strictly aerobic, non-fermentative, oxidase and catalase positive, rod-shaped, and motile due to a polar inserted flagellum. Phylogenetic analysis of the 16S rRNA gene and three other housekeeping genes placed strain L48 (T) in the Pseudomonas putida phylogenetic group. DNA-DNA hybridisation studies together with phenotypic metabolic tests and MALDI-TOF MS analysis justified the proposal of strain L48(T) as a representative of a novel species, for which the name Pseudomonas entomophila sp. nov. is proposed. The type strain is deposited in culture collections under accession numbers CCUG 61470(T) and CECT 7985(T).  相似文献   
902.
doi: 10.1111/j.1741‐2358.2011.00545.x Nutritional status, dietary intake and oral quality of life in elderly complete denture wearers Background and objective: The prevalence of malnutrition increases with age because of many factors. Edentulousness leads to the avoidance of many types of foods. The aim of this study was to determine whether elderly complete denture wearers have a higher risk of malnutrition than dentate controls. Material and methods: A Mini‐Nutritional Assessment (MNA) and a 3‐day dietary record were compiled for a group of fully dentates (21 women and 29 men; mean age 70.1 ± 6.1) and for a group of complete denture wearers (31 women and 16 men; mean age 70.1 ± 8.1). Socio‐demographic data and scores on the General Oral Health Assessment Index (GOHAI) questionnaire were collected. Results: Inter‐group comparison of MNA scores showed that more subjects in the edentulous group (21.3%) risked malnutrition than in the dentate group (0%). The variability of the MNA could be explained for 22% by dental status, 7% by loneliness and 4% by the GOHAI score (regression analysis). Both groups had insufficient energy intakes and deficits in vitamins and micronutrients; moreover, edentulous subjects had lower intakes than dentate subjects. Conclusion: The use of conventional dentures increases the risk of malnutrition in the elderly.  相似文献   
903.
The multidimensional nature of animal signals makes acoustic traits potentially subject to different determinants. The Amazonian frogs Allobates nidicola and Allobates masniger have an allopatric distribution, occurring along the left and right sides of the Madeira River, respectively. These are two sister, phenotypically similar species whose eggs are deposited and develop entirely in a terrestrial nest. In this study, we analyzed 2,000 advertisement calls recorded from ten localities across Central Amazonia, in order to understand the role of determinants of acoustic signal variability at the population and species levels. We assessed, through nested analyses of variance, the differentiation of six characters of this sexual signal among populations and between interfluves. Moreover, we measured the degree of variability and the extent of temperature- and body size-induced plasticity in call traits. We also tested for isolation-by-distance effects in phenotypic differentiation through Mantel tests. Coefficients of variation were higher among than within populations for all call measurements. Spectral call properties were more distinctive than temporal traits among populations and species. Advertisement call traits showed strong temperature-induced plasticity (e.g., 45?% of the variation in note duration). In contrast, the effects of body size were restricted to frequency-related characters. The river barrier effect was significant among all the acoustic variables analyzed even after controlling for male body size. Geography (sampling locality) and body size also jointly affected call variability. No correlation between geographical and acoustic distances among populations was observed, suggesting that local stabilizing selective pressures have an important role in the evolution of call differentiation.  相似文献   
904.
Although abdominal cryptococcomas and visceral cryptococcal lymphadenitis as part of disseminated fungal infection have been reported mostly in HIV-infected patients, localized intra-abdominal involvement due to Cryptococcus gattii has not been previously described in non-HIV-infected patients. In general, a smaller proportion of cryptococcosis is caused by C. gattii. We report here on a type II diabetic HIV-negative patient who presented with a localized intra-abdominal cryptococcal mass due to C. gattii. In addition, we review the general aspects of intra-abdominal and gastrointestinal involvement by Cryptococcus neoformans in the literature and discuss the importance of identifying the C. neoformans varieties and C. gattii in routine laboratories.  相似文献   
905.
The influenza A virus genome consists of eight viral RNAs (vRNAs) that form viral ribonucleoproteins (vRNPs). Even though evidence supporting segment-specific packaging of vRNAs is accumulating, the mechanism ensuring selective packaging of one copy of each vRNA into the viral particles remains largely unknown. We used electron tomography to show that the eight vRNPs emerge from a common 'transition zone' located underneath the matrix layer at the budding tip of the virions, where they appear to be interconnected and often form a star-like structure. This zone appears as a platform in 3D surface rendering and is thick enough to contain all known packaging signals. In vitro, all vRNA segments are involved in a single network of intermolecular interactions. The regions involved in the strongest interactions were identified and correspond to known packaging signals. A limited set of nucleotides in the 5' region of vRNA 7 was shown to interact with vRNA 6 and to be crucial for packaging of the former vRNA. Collectively, our findings support a model in which the eight genomic RNA segments are selected and packaged as an organized supramolecular complex held together by direct base pairing of the packaging signals.  相似文献   
906.

Background and Aims

Advanced phenotyping, i.e. the application of automated, high-throughput methods to characterize plant architecture and performance, has the potential to accelerate breeding progress but is far from being routinely used in current breeding approaches. In forage and turf improvement programmes, in particular, where breeding populations and cultivars are characterized by high genetic diversity and substantial genotype × environment interactions, precise and efficient phenotyping is essential to meet future challenges imposed by climate change, growing demand and declining resources.

Scope

This review highlights recent achievements in the establishment of phenotyping tools and platforms. Some of these tools have originally been established in remote sensing, some in precision agriculture, while others are laboratory-based imaging procedures. They quantify plant colour, spectral reflection, chlorophyll-fluorescence, temperature and other properties, from which traits such as biomass, architecture, photosynthetic efficiency, stomatal aperture or stress resistance can be derived. Applications of these methods in the context of forage and turf breeding are discussed.

Conclusions

Progress in cutting-edge molecular breeding tools is beginning to be matched by progress in automated non-destructive imaging methods. Joint application of precise phenotyping machinery and molecular tools in optimized breeding schemes will improve forage and turf breeding in the near future and will thereby contribute to amended performance of managed grassland agroecosystems.  相似文献   
907.

Background and Aims

Hydrophytes generally exhibit highly acquisitive leaf economics. However, a range of growth forms is evident, from small, free-floating and rapidly growing Lemniden to large, broad-leaved Nymphaeiden, denoting variability in adaptive strategies. Traits used to classify adaptive strategies in terrestrial species, such as canopy height, are not applicable to hydrophytes. We hypothesize that hydrophyte leaf size traits and economics exhibit sufficient overlap with terrestrial species to allow a common classification of plant functional types, sensu Grime''s CSR theory.

Methods

Leaf morpho-functional traits were measured for 61 species from 47 water bodies in lowland continental, sub-alpine and alpine bioclimatic zones in southern Europe and compared against the full leaf economics spectrum and leaf size range of terrestrial herbs, and between hydrophyte growth forms.

Key Results

Hydrophytes differed in the ranges and mean values of traits compared with herbs, but principal components analysis (PCA) demonstrated that both groups shared axes of trait variability: PCA1 encompassed size variation (area and mass), and PCA2 ranged from relatively dense, carbon-rich leaves to nitrogen-rich leaves of high specific leaf area (SLA). Most growth forms exhibited trait syndromes directly equivalent to herbs classified as R adapted, although Nymphaeiden ranged between C and SR adaptation.

Conclusions

Our findings support the hypothesis that hydrophyte adaptive strategy variation reflects fundamental trade-offs in economics and size that govern all plants, and that hydrophyte adaptive strategies can be directly compared with terrestrial species by combining leaf economics and size traits.  相似文献   
908.
The chromogranin A (CHGA)-derived peptide catestatin (CST: hCHGA(352-372)) is a noncompetitive catecholamine-release inhibitor that exerts vasodilator, antihypertensive, and cardiosuppressive actions. We have shown that CST directly influences the basal performance of the vertebrate heart where CST dose dependently induced a nitric oxide-cGMP-dependent cardiosuppression and counteracted the effects of adrenergic stimulation through a noncompetitive antagonism. Here, we sought to determine the specific intracardiac signaling activated by CST in the rat heart. Physiological analyses performed on isolated, Langendorff-perfused cardiac preparations revealed that CST-induced negative inotropism and lusitropism involve β(2)/β(3)-adrenergic receptors (β(2)/β(3)-AR), showing a higher affinity for β(2)-AR. Interaction with β(2)-AR activated phosphatidylinositol 3-kinase/endothelial nitric oxide synthase (eNOS), increased cGMP levels, and induced activation of phosphodiesterases type 2 (PDE2), which was found to be involved in the antiadrenergic action of CST as evidenced by the decreased cAMP levels. CST-dependent negative cardiomodulation was abolished by functional denudation of the endothelium with Triton. CST also increased the eNOS expression in cardiac tissue and human umbilical vein endothelial cells. cells, confirming the involvement of the vascular endothelium. In ventricular extracts, CST increased S-nitrosylation of both phospholamban and β-arrestin, suggesting an additional mechanism for intracellular calcium modulation and β-adrenergic responsiveness. We conclude that PDE2 and S-nitrosylation play crucial roles in the CST regulation of cardiac function. Our results are of importance in relation to the putative application of CST as a cardioprotective agent against stress, including excessive sympathochromaffin overactivation.  相似文献   
909.
910.
Glutamine (gln) is the most abundant free amino acid in the blood. It is involved in important metabolic and biochemical processes, like cell proliferation and oxidative stress. Previous studies have demonstrated that gln concentration in human plasma decreases in several conditions such as sepsis, ischemia-reperfusion, trauma, major surgery and burn. The aim of the present work was to compare the acute effects of different types of surgical interventions and of anesthetization on blood gln concentration. Plasma samples from 88 subjects (30 males and 58 females) were collected before and after major or minor surgery and the gln concentration was analyzed with high-performance liquid chromatography. The results showed that plasma gln concentration after surgery was lower than pre-surgery values and that in major surgery the decrease of gln was higher than in minor surgery. No significant effect was shown for sex or type of anesthesia. These results demonstrate the importance of a gln supplementation before a surgical intervention and show that the amount of gln supplementation should also be adjusted based on the type of surgery.  相似文献   
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