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121.
Life cycle assessment (LCA) was used to compare the current water supply planning in Mediterranean Spain, the so‐called AGUA Programme, with its predecessor, the Ebro river water transfer (ERWT). Whereas the ERWT was based on a single interbasin transfer, the AGUA Programme excludes new transfers and focuses instead on different types of resources, including seawater and brackish water desalination and wastewater reuse, among others. The study includes not only water supply but the whole anthropic cycle of water, from water abstraction to wastewater treatment. In addition to standard LCA impact categories, a specific impact category focusing on freshwater resources is included, which takes into account freshwater scarcity in the affected water catchments. In most impact categories the AGUA Programme obtains similar or even lower impact scores than ERWT. Concerning impacts on freshwater resources, the AGUA Programme obtains an impact score 49% lower than the ERWT. Although the current water planning appears to perform better in many impact categories than its predecessor, this study shows that water supply in Spanish Mediterranean regions is substantially increasing its energy intensity and that Mediterranean basins suffer a very high level of water stress due to increasing demand and limited resources.  相似文献   
122.
Saccharomyces cerevisiae NAD(H)‐dependent 2,3‐butanediol dehydrogenase (Bdh1), a medium chain dehydrogenase/reductase is the main enzyme catalyzing the reduction of acetoin to 2,3‐butanediol. In this work we focused on altering the coenzyme specificity of Bdh1 from NAD(H) to NADP(H). Based on homology studies and the crystal structure of the NADP(H)‐dependent yeast alcohol dehydrogenase Adh6, three adjacent residues (Glu221, Ile222, and Ala223) were predicted to be involved in the coenzyme specificity of Bdh1 and were altered by site‐directed mutagenesis. Coenzyme reversal of Bdh1 was obtained with double Glu221Ser/Ile222Arg and triple Glu221Ser/Ile222Arg/Ala223Ser mutants. The performance of the triple mutant for NADPH was close to that of native Bdh1 for NADH. The three engineered mutants were able to restore the growth of a phosphoglucose isomerase deficient strain (pgi), which cannot grow on glucose unless an alternative NADPH oxidizing system is provided, thus demonstrating their in vivo functionality. These mutants are interesting tools to reduce the excess of acetoin produced by engineered brewing or wine yeasts overproducing glycerol. In addition, they represent promising tools for the manipulation of the NADP(H) metabolism and for the development of a powerful catalyst in biotransformations requiring NADPH regeneration. Biotechnol. Bioeng. 2009; 104: 381–389 © 2009 Wiley Periodicals, Inc.  相似文献   
123.
In this study, we report the role of exogenous and endogenous cytokinins on growth and sexual organ development in the fern Blechnum spicant L. Spore-derived gametophytes (SG) were cultured in full-strength Murashige and Skoog (1962) liquid medium supplemented with (a) 4.44 μMN6-benzyladenine (BAP), (b) a crude extract from mature female gametophytes, and (c) 4.44 μM BAP in combination with the crude extract from mature gametophytes, respectively. Both BAP and the crude extract delayed the gametophyte development, and this effect was increased when they were added together. With respect to sexual organ development, BAP inhibited the sexual organ formation, while the crude extract favored antheridia formation; however, when added together, the percentage of antheridia decreased. The endogenous level of the cytokinins cis-zeatin (cZ), cis-zeatin-riboside (cZR), dihydrozeatin (DHZ), dihydrozeatin riboside (DHZR), isopentenyl adenine (iP), isopentenyl adenosine (iPR), isopentenyl-9-glucoside (iP9G), trans-zeatin (tZ), and trans-zeatin riboside (tZR) were analyzed in female and male gametophytes of B. spicant L. The endogenous levels of cytokinins tZ, cZ, DHZ, cZR, iP, and iPR were higher in female gametophytes than in male gametophytes, with the endogenous iP and iPR content being increased more than 300 and 400 times, respectively.  相似文献   
124.

Background

Trypanosoma cruzi is the causative agent of Chagas'' Disease. The parasite has a complex population structure, with six major evolutionary lineages, some of which have apparently resulted from ancestral hybridization events. Because there are important biological differences between these lineages, strain typing methods are essential to study the T. cruzi species. Currently, there are a number of typing methods available for T. cruzi, each with its own advantages and disadvantages. However, most of these methods are based on the amplification of a variable number of loci.

Methodology/Principal Findings

We present a simple typing assay for T. cruzi, based on the amplification of a single polymorphic locus: the TcSC5D gene. When analyzing sequences from this gene (a putative lathosterol/episterol oxidase) we observed a number of interesting polymorphic sites, including 1 tetra-allelic, and a number of informative tri- and bi-allelic SNPs. Furthermore, some of these SNPs were located within the recognition sequences of two commercially available restriction enzymes. A double digestion with these enzymes generates a unique restriction pattern that allows a simple classification of strains in six major groups, corresponding to DTUs TcI–TcIV, the recently proposed Tcbat lineage, and TcV/TcVI (as a group). Direct sequencing of the amplicon allows the classification of strains into seven groups, including the six currently recognized evolutionary lineages, by analyzing only a few discriminant polymorphic sites.

Conclusions/Significance

Based on these findings we propose a simple typing assay for T. cruzi that requires a single PCR amplification followed either by restriction fragment length polymorphism analysis, or direct sequencing. In the panel of strains tested, the sequencing-based method displays equivalent inter-lineage resolution to recent multi- locus sequence typing assays. Due to their simplicity and low cost, the proposed assays represent a good alternative to rapidly screen strain collections, providing the cornerstone for the development of robust typing strategies.  相似文献   
125.
The effect of a superactive agonistic analog of luteinizing hormone-releasing hormone (LHRH), [D-Trp6]LHRH on prolactin (PRL) secretion by perifused rat pituitary cells was investigated. Constant infusion of [D-Trp6]LHRH (0.5 ng/min) for 2-3 h elicited a significant decrease in PRL secretion by these cells. This decrease in PRL release started ca. 30 min after the beginning of the infusion with the LHRH analog and lasted up to 1.5-2 h. [D-Trp6]LHRH significantly stimulated luteinizing hormone (LH) secretion during the first 30 min of peptide infusion; thereafter, LH levels began to return to control values. In animals pretreated in vivo with 50 micrograms of [D-Trp6]LHRH (s.c.) 1 h before sacrifice, PRL secretion by the rat pituitary cell perifusion system was significantly lower than vehicle-injected controls throughout the entire [D-Trp6]LHRH infusion period. On the other hand, thyrotropin-releasing hormone (TRH)-stimulated PRL secretion was slightly, but significantly imparied by [D-Trp6]LHRH infusion, while dopamine (DA) inhibition of PRL release was unaffected by this same treatment. These results reinforce previous observations of a modulatory effect of [D-Trp6]LHRH, probably mediated by pituitary gonadotrophs, on PRL secretion by the anterior pituitary. In addition, our findings suggest that basal PRL secretion by the lactotroph may be dependent on a normal function of the gonadotroph. The collected data from this and previous reports support the existence of a functional link between gonadotrophs and lactotrophs in the rat pituitary gland.  相似文献   
126.
International Journal of Peptide Research and Therapeutics - Gardnerella vaginalis produces vaginolysin (VLY), a cholesterol-dependent cytolysin, responsible of the cellular lysis and epithelial...  相似文献   
127.
Many bark beetles live in a symbiosis with ophiostomatoid fungi but very little is known regarding these fungi in Spain. In this study, we considered the fungi associated with nine bark beetle species and one weevil infesting two native tree species (Pinus sylvestris and Pinus nigra) and one non-native (Pinus radiata) in Cantabria (Northern Spain). This included examination of 239 bark beetles or their galleries. Isolations yielded a total of 110 cultures that included 11 fungal species (five species of Leptographium sensu lato including Leptographium absconditum sp. nov., five species of Ophiostoma sensu lato including Ophiostoma cantabriense sp. nov, and one species of Graphilbum). The most commonly encountered fungal associates of the bark beetles were Grosmannia olivacea, Leptographium procerum, and Ophiostoma canum. The aggressiveness of the collected fungal species was evaluated using inoculations on two-year-old P. radiata seedlings. Leptographium wingfieldii, Leptographium guttulatum, and Ophiostoma ips were the only species capable of causing significant lesions.  相似文献   
128.
At 4 days after the implantation of two subcutaneous 75 mg morphine pellets in the back skin, rats were morphine-dependent. In the three layers studied in the occipital cortex we found that the values of the 2-adrenergic agonist [3H]bromoxidine binding increased with respect to animals implanted with placebo pellets. Typical behavioral and physiological symptoms of the abstinence syndrome appeared 30 minutes after administration of naloxone, [3H]bromoxidine binding values being similar to those obtained in animals implanted with placebo pellets. The pattern of response of the [3H]bromoxidine binding was similar in the hippocampus and the superficial gray layer of the superior colliculus of the mesencephalon, but the differences were not statistically significant in these areas. This paper concludes that exist brain regional differences in the 2-adrenoreceptors response under morphine-treatment and possibly under naloxone-induced morphine abstinence syndrome.  相似文献   
129.
130.
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