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341.
The amounts of Fe, Zn, Cu, Mg were determined in the inner and outer layers of shells of Mytilus g.. Different values significatively between the layers were found only for Mg. The ratio [Me]Calcite/ [Me]Aragonite was calculated and it is not more than one, for all the colonies of different sampling zones. The Authors conclude that perhaps the reason of this behaviour is the different pollution of their habitat.  相似文献   
342.
Several aromatic/heterocyclic sulfonamide scaffolds have been used to synthesize compounds incorporating NO-donating moieties of the nitrate ester type, which have been investigated for the inhibition of five physiologically relevant human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms: hCA I (offtarget), II, IV and XII (antiglaucoma targets) and IX (antitumor target). Some of the new compounds showed effective in vitro inhibition of the target isoforms involved in glaucoma, and the X-ray crystal structure of one of them revealed factors associated with the marked inhibitory activity. In an animal model of ocular hypertension, one of the new compounds was twice more effective than dorzolamide in reducing elevated intraocular pressure characteristic of this disease, anticipating their potential for the treatment of glaucoma.  相似文献   
343.

Background

Use of peripheral blood- or bone marrow-derived progenitors for ischemic heart repair is a feasible option to induce neo-vascularization in ischemic tissues. These cells, named Endothelial Progenitors Cells (EPCs), have been extensively characterized phenotypically and functionally. The clinical efficacy of cardiac repair by EPCs cells remains, however, limited, due to cell autonomous defects as a consequence of risk factors. The devise of “enhancement” strategies has been therefore sought to improve repair ability of these cells and increase the clinical benefit.

Principal Findings

Pharmacologic inhibition of histone deacetylases (HDACs) is known to enhance hematopoietic stem cells engraftment by improvement of self renewal and inhibition of differentiation in the presence of mitogenic stimuli in vitro. In the present study cord blood-derived CD34+ were pre-conditioned with the HDAC inhibitor Valproic Acid. This treatment affected stem cell growth and gene expression, and improved ischemic myocardium protection in an immunodeficient mouse model of myocardial infarction.

Conclusions

Our results show that HDAC blockade leads to phenotype changes in CD34+ cells with enhanced self renewal and cardioprotection.  相似文献   
344.
The Afrotropical flea beetle genus Notomela Jacoby, 1899 is reviewed. Notomela joliveti sp.n. from Principe Island is described. The following new synonymies are established: Notomela cyanipennis Jacoby, 1899 = Notomela viridipennis Bryant, 1941, syn. n. = Notomela cyanipennis macrosoma Bechyné, 1959, syn. n. In addition, the new combination is established: Notomela fulvofasciata Jacoby, 1903 is transfered to Amphimela [Amphimela fulvofasciata (Jacoby, 1903), comb. n.]. Micrographs of male and female genitalia, scanning electron micrographs of some diagnostic morphological characters, a key to identification, and distributional data for all species of Notomela, are provided.  相似文献   
345.
One of the limitations of the use of phage antibody libraries in high throughput selections is the production of sufficient phage antibody library at the appropriate quality. Here, we successfully adapt a bioreactor-based protocol for the production of phage peptide libraries to the production of phage antibody libraries. The titers obtained in the stirred-tank bioreactor are 4 to 5 times higher than in a standard shake flask procedure, and the quality of the phage antibody library produced is indistinguishable to that produced using standard procedures as assessed by Western blotting and functional selections. Availability of this protocol will facilitate the use of phage antibody libraries in high-throughput scale selections.  相似文献   
346.
347.
Biodiversity hotspots are routinely identified by grid-based analyses, despite grids encompassing different habitats, thus hindering the potential to assess which habitat type accounts for the conservation priority assigned to a grid. In this study, we aimed at identifying the main hotspots for the conservation of the European stygobitic Crustacea Copepoda Harpacticoida at the groundwater habitat scale. A multi-metric approach was used, based on six biodiversity indicators: species richness, endemicity, evolutionary origin, phylogenetic rarity, taxonomic distinctness, habitat specificity. The Hot Spot Analysis, based on the statistics Getis-Ord Gi*, was used to compare the local to the global average values of each indicator to identify hotspots of conservation. The operational units used to perform the analyses were the groundwater habitat types, in order to gather all the possible patterns of spatial occupancy in terms of habitat variability. Eight biodiversity hotspots of stygobitic Crustacea Harpacticoida were highlighted: 1) the Pyrenees (Spain and France), 2) the Jura Massif (France), 3) the Alpine arc (France, Switzerland and Italy) embracing southward the River Po alluvial plain and the Slovenian External Dinarides, 4) the Central Apennines (Italy), 5) the Carpathian and Balkan mountains in Romania and at the boundary between western Bulgaria and north-west Macedonia, 6) the Dinaric Alps (from Croatia to Albania), 7) the Sardinia Island, 8) an area in central-northern Europe embracing Denmark, the Netherlands and Germany. The hotspots showed a clear spatial distribution in southern Europe where they were distributed predominantly south to the 45th parallel, in line to what reiteratively observed in previous studies. Many hotspots embraced more than one habitat type. The adoption of discrete groundwater habitat types as working spatial units rather than grids provided a higher resolution of where the stygobitic harpacticoid species effectively live, with the possibility of intervening more precisely to preserve them and their habitats.  相似文献   
348.
Pseudovivipary is an asexual reproduction strategy correlated with extreme environments. Comanthera nivea occurs in habitats with low water retention. This study investigated the effect of soil moisture availability on C. nivea pseudoviviparous reproduction and flowering. We established four permanent plots (1 × 1 m), two in a shaded area, in which we marked 15 rosettes in each plot, and two in a full-sun area, in which we marked 10 rosettes in each plot. We made monthly observations from August 2016 to January 2017, to quantify the number of flower heads and of pseudoviviparous ramets per rosette, and measured soil moisture. Our results showed a high correlation between soil moisture and flowering. Flowering in C. nivea occurs in periods of increased soil moisture, whereas pseudoviviparous reproduction occurs in the driest period. The advantages of a pseudoviviparous canopy-forming strategy in habitats with scarcity of water in the soil are discussed.  相似文献   
349.
The damsel bug, Nabis pseudoferus Remane (Hemiptera: Namidae), is a generalist predator of small arthropods, including key insect pests of vegetable crops. In this study, we characterized the predation and development of various N. pseudoferus life stages when preying on the eggs and first- and fourth-instar nymphs of the invasive South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). These findings were compared to those of the bug’s common prey, cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae). Of the life stages tested, females showed the highest predation rate on all tested prey, due to their high longevity, large body, and great energy requirements for reproduction. The predator’s oviposition rate was clearly influenced by prey type, and was highest when feeding on fourth instars of T. absoluta. Considering the zoophytophagy of most of the life stages of other mirid species of tomato, and the lower propensity of N. pseudoferus to feed on plants, these results show that this species can be considered as a key indigenous natural enemy for sustainable pest control packages against T. absoluta in newly invaded areas.  相似文献   
350.
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