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101.

Purpose  

At present, many urban areas in Mediterranean climates are coping with water scarcity, facing a growing water demand and a limited conventional water supply. Urban design and planning has so far largely neglected the benefits of rainwater harvesting (RWH) in the context of a sustainable management of this resource. Therefore, the purpose of this study was to identify the most environmentally friendly strategy for rainwater utilization in Mediterranean urban environments of different densities.  相似文献   
102.
Most cyanobacteria take up nitrate or nitrite through a multisubunit ABC transporter (ATP-binding cassette) located in the cytoplasmic membrane. Nitrate and nitrite transport activity is instantaneously blocked by the presence of ammonium in the medium. Previous biochemical studies reported the existence of phosphorylation/dephosphorylation events of the nitrate transporter (NRT) related to the presence of ammonium-sensitive kinase/phosphatase activities in plasma membranes of the cyanobacterium Synechococcus elongatus PCC 6301. In this work, we have analyzed the biochemical properties of the periplasmic nitrate/nitrite-binding subunit (NrtA) of NRT from the thermophilic nondiazotrophic cyanobacterium Phormidium laminosum. Our results show that cyanobacterial NrtA is phosphorylated in vivo. However, substrate binding activity in vitro is not affected by the phosphorylation state of the protein, ruling out the possibility that phosphorylation/dephosphorylation of NrtA is involved in the regulation of the nitrate/nitrite uptake by NRT transporter. Moreover, NrtA is present as multiple isoforms showing the same molecular mass but different isoelectric points ranging from pI 5 to 6. Mass spectrometric characterization of NrtA isoforms shows that the protein is phosphorylated at residue Tyr203, and contains several methionine sulphoxide residues which account for the observed isoforms. Both phosphorylated and non-phosphorylated forms of NrtA are active in vitro, showing comparable binding affinity for nitrate and nitrite. Both substrates behave as pure competitive inhibitors with a binding stoichiometry of one molecule of anion per NrtA monomer.  相似文献   
103.
A new series of 4-(1,3-dialkyl-2,4-dioxo-2,3,4,5-tetrahydro-1H-pyrrolo[3,2-d]pyrimidin-6-yl)benzenesulfonamides has been identified as potent A2B adenosine receptor antagonists. The products have been evaluated for their binding affinities for the human A2B, A1 and A3 adenosine receptors. 6-(4-{[4-(4-Bromobenzyl)piperazin-1-yl]sulfonyl}phenyl)-1,3-dimethyl-1H-pyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (16) showed a high affinity for the A2B adenosine receptor (IC50=1 nM) and selectivity (A1: 183x; A3: 12660x). Synthesis and SAR of this novel class of compounds showing improved absorption properties is presented herein.  相似文献   
104.
This work presents a Biological Resource Bank generated as a complementary supporting tool for the reproduction and the in situ and ex situ conservation of the Iberian lynx. In its design we prioritized the preservation of a maximum of the current genetic and biological diversity of the population, and the harmless collection of the samples. To provide future reproductive opportunities through any possible technique, we processed and cryopreserved germinal cells and tissues from dead animals, 7 males and 6 females, as well as somatic cells and tissues from 69 different individuals. This somatic cell reserve reflects a very important fraction of the population biodiversity which, furthermore, will allow the development of a wide variety of studies that can be easily extrapolated to the majority of the population. We have developed a new non-destructive method to isolate cells with stem-cell-like properties. If considered convenient in the future, and after proper research, such cells could permit therapeutic applications and perhaps be a good source to be used in somatic cell nuclear transfer. Samples of whole blood and its derivatives, hairs, urine and feces from many different individuals were also preserved. Proper storage of such samples is required to allow epidemiological studies to be performed for the testing of different etiological hypotheses or, in general, to develop any bio-sanitary study to improve conservation strategies within the natural habitat. This work describes the main aspects involved in the practical implementation of the Iberian lynx Biological Resource Bank, as a model that could be useful for the development of similar banks for other endangered species.  相似文献   
105.
In the first step of this investigation the toxicity of Ni2+, Cu2+, and Zn2+ ions to the emulsifier producing strain of Curvularia lunata was assessed. Among all the heavy metals studied, Ni2+ ions were found to be the most toxic to C. lunata, whereas Zn2+ ions exhibited the lowest toxicity. Moreover, only Ni2+, when used at sublethal concentration (5 mM) caused lysis of some hyphal tip cells after a short-term exposure (5 h). In the next step, emulsifier production, accumulation of heavy metals by mycelia and emulsifier as well as saturation of cellular fatty acids were examined in 48-h-old cultures where fungal growth intensity was not inhibited by heavy metals (in the presence of Ni2+, Cu2+, and Zn2+ ions at the initial concentration of 1, 5, and 15 mM, respectively) and in cultures where approximately 50% biomass inhibition occurred (in the presence of Ni2+, Cu2+, and Zn2+ ions at the initial concentrations of 3, 10, and 17.5 mM, respectively). Among all the heavy metals studied only Ni2+ ions did not induce emulsifier production. As compared with the control, only biomass treated with Ni2+ ions displayed an increase in total lipid saturation. This effect resulted mainly from the decrease in linoleic acid (18:2) content correlated with the increase in the amount of stearic acid (18:0). The possible mechanisms by which Ni2+ ions could alter the fatty acid profile of C. lunata and the protective role of the emulsifier were also discussed.  相似文献   
106.
Epithelial cells express calcium-activated Cl(-) channels of unknown molecular identity. These Cl(-) channels play a central role in diseases such as secretory diarrhea, polycystic kidney disease, and cystic fibrosis. The family of bestrophins has been suggested to form calcium-activated Cl(-) channels. Here, we demonstrate molecular and functional expression of bestrophin-1 (BEST1) in mouse and human airways, colon, and kidney. Endogenous calcium-activated whole cell Cl(-) currents coincide with endogenous expression of the Vmd2 gene product BEST1 in murine and human epithelial cells, whereas calcium-activated Cl(-) currents are absent in epithelial tissues lacking BEST1 expression. Blocking expression of BEST1 with short interfering RNA or applying an anti-BEST1 antibody to a patch pipette suppressed ATP-induced whole cell Cl(-) currents. Calcium-dependent Cl(-) currents were activated by ATP in HEK293 cells expressing BEST1. Thus, BEST1 may form the Ca2+-activated Cl(-) current, or it may be a component of a Cl(-) channel complex in epithelial tissues.  相似文献   
107.
108.
The synthesis and SAR of a series of N-(5,6-diarylpyridin-2-yl)amide derivatives as potent A2B adenosine receptor antagonists is described. Several compounds showed good selectivity versus other adenosine receptors. The potent and selective analogue 9 was shown to have good oral bioavailability in the rat.  相似文献   
109.
Evidence for the importance of major histocompatibility complex (MHC) genotype in immunological fitness of chickens continues to accumulate. The MHC B haplotypes contribute resistance to Marek's and other diseases of economic importance. The Rfp-Y, a second cluster of MHC genes in the chicken, may also contribute to disease resistance. Nevertheless, the MHC B and Rfp-Y haplotypes segregating in broiler chickens are poorly documented. The Camperos, free-range broiler chickens developed in Argentina, provide an opportunity to evaluate MHC diversity in a genetically diverse broiler stock. Camperos are derived by cross-breeding parental stocks maintained essentially without selection since their founding. We analysed 51 DNA samples from the Camperos and their parental lines for MHC B and Rfp-Y variability by restriction fragment pattern (rfp) and SSCP typing methods for B-G, B-F (class Ia), B-Lbeta (class II) and Y-F (class Ib) diversity. We found evidence for 38 B-G genotypes. The Camperos B-G patterns were not shared with White Leghorn controls, nor were any of a limited number of Camperos B-G gene sequences identical to published B-G sequences. The SSCP assays provided evidence for the presence of at least 28 B-F and 29 B-Lbeta genotypes. When considered together B-F, B-L, and B-G patterns provide evidence for 40 Camperos B genotypes. We found even greater Rfp-Y diversity. The Rfp-Y class I-specific probe, 163/164f, revealed 44 different rfps among the 51 samples. We conclude that substantial MHC B and Rfp-Y diversity exists within broiler chickens that might be drawn upon in selecting for desirable immunological traits.  相似文献   
110.
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