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71.
72.
Mireille Faist Emmenegger Stephan Pfister Annette Koehler Luca de Giovanetti Alejandro Pablo Arena Rainer Zah 《The International Journal of Life Cycle Assessment》2011,16(9):869-877
Purpose
The assessment of biofuels has until now mainly focused on energy demand and greenhouse gas emissions. Only little attention has been given to other impacts, although the general importance of water use for the life cycle assessment (LCA) of agricultural products has been recognized in recent publications. The aim of this work is to assess in detail the water consumption along a biofuel production chain taking into account irrigation efficiencies, levels of water scarcity, and type of feedstock, and to integrate those results in a full LCA. Furthermore, we compare the results for biofuels from various feedstocks and regions with conventional petrol. 相似文献73.
74.
75.
Aneuploidy, the relative excess or deficiency of specific chromosome types, results in gene dosage imbalance. Plants can produce viable and fertile aneuploid individuals, while most animal aneuploids are inviable or developmentally abnormal. The swarms of aneuploid progeny produced by Arabidopsis triploids constitute an excellent model to investigate the mechanisms governing dosage sensitivity and aneuploid syndromes. Indeed, genotype alters the frequency of aneuploid types within these swarms. Recombinant inbred lines that were derived from a triploid hybrid segregated into diploid and tetraploid individuals. In these recombinant inbred lines, a single locus, which we call SENSITIVE TO DOSAGE IMBALANCE (SDI), exhibited segregation distortion in the tetraploid subpopulation only. Recent progress in quantitative genotyping now allows molecular karyotyping and genetic analysis of aneuploid populations. In this study, we investigated the causes of the ploidy-specific distortion at SDI. Allele frequency was distorted in the aneuploid swarms produced by the triploid hybrid. We developed a simple quantitative measure for aneuploidy lethality and using this measure demonstrated that distortion was greatest in the aneuploids facing the strongest viability selection. When triploids were crossed to euploids, the progeny, which lack severe aneuploids, exhibited no distortion at SDI. Genetic characterization of SDI in the aneuploid swarm identified a mechanism governing aneuploid survival, perhaps by buffering the effects of dosage imbalance. As such, SDI could increase the likelihood of retaining genomic rearrangements such as segmental duplications. Additionally, in species where triploids are fertile, aneuploid survival would facilitate gene flow between diploid and tetraploid populations via a triploid bridge and prevent polyploid speciation. Our results demonstrate that positional cloning of loci affecting traits in populations containing ploidy and chromosome number variants is now feasible using quantitative genotyping approaches. 相似文献
76.
77.
Roberta Davoli Greta Gandolfi Silvia Braglia Marco Comella Paolo Zambonelli Luca Buttazzoni Vincenzo Russo 《Molecular biology reports》2011,38(3):1575-1583
PLIN2 (perilipin 2) is a cytosolic protein that promotes the formation and stabilization of the intracellular lipid droplets,
organelles involved in the storage of lipid depots. Porcine PLIN2 gene represents a biological and positional candidate for fat deposition, a polygenic trait that affects carcass and meat
quality. The aim of the present study was to screen PLIN2 gene for polymorphisms, to evaluate the association with carcass quality traits, and to investigate the gene expression in
skeletal muscle. Six new single nucleotide polymorphisms (SNP) were detected by sequencing 32 samples from five pig breeds
(Italian Large White, Italian Duroc, Italian Landrace, Belgian Landrace, Pietrain). Two SNP localized in introns, two in the
3′-untranslated region (UTR), and two missense SNP were found in exons. A 3′-UTR mutation (GU461317:g.98G>A), genotyped in
290 Italian Duroc pigs by High Resolution Melting, resulted significantly associated (P < 0.01) with average daily gain, feed conversion ratio, lean cuts and hams weight estimated breeding values. PLIN2 gene expression analysis in skeletal muscle of Italian Large White and Italian Duroc pigs divergent for backfat thickness
and visible intermuscular fat showed a trend of higher expression level in pigs with higher intermuscular fat. These results
suggest that PLIN2 can be a marker for carcass quality in pigs. Further investigation at both gene and protein level could elucidate its role
on fat deposition. 相似文献
78.
Dolci LS Marzocchi E Montalti M Prodi L Monti D Di Natale C D'Amico A Paolesse R 《Biosensors & bioelectronics》2006,22(3):399-404
Deposition of amphiphilic porphyrin derivatives occurs spontaneously on silanised glass surfaces, in a controlled fashion. The resulting porphyrin films show appreciable fluorescence emission. This emission can be effectively quenched by immersion of the slides into a diluted solution of Hg(2+) (microM concentration). The initial intensity can be restored by washings with a solution of N,N,N',N'-tetrakis(2-pyridilmethyl)ethylenediammine with no loss of efficiency. A remarkable selectivity is featured toward the detection of Hg(2+) over Cu(2+), Cd(2+), Pb(2+) and Zn(2+) counterparts. This protocol can be extended to a flow-through apparatus. The presented results are of importance for the achievement of a solid-state chemosensor for mercuric ions, at micromolar concentration, in water. 相似文献
79.
Luca Piccoli Francesca Tamarozzi Federico Cattaneo Mara Mariconti Carlo Filice Antonella Bruno Enrico Brunetti 《PLoS neglected tropical diseases》2014,8(8)
Human cystic echinococcosis is a chronic, complex and neglected infection. Its clinical management has evolved over decades without adequate evaluation of efficacy. Recent expert opinion recommends that uncomplicated inactive cysts of the liver should be left untreated and solely monitored over time (“watch-and-wait” approach). However, clinical data supporting this approach are still scant and published mostly as conference proceedings. In this study, we report our experience with long-term sonographic and serological follow-up of inactive cysts of the liver. From March 1994 to October 2013, 38 patients with 47 liver cysts, diagnosed as inactive without any previous treatment history, were followed with ultrasound and serology at 6–12 months intervals for a period of at least 24 months (median follow-up 51.95 months) in our outpatient clinic. In 97.4% of patients, the cysts remained inactive over time and in only one case was reactivation of the cyst detected. No complications occurred during the time of monitoring. During follow-up, serology tests for CE were negative at diagnosis or became negative in 74.1% and were positive or became positive in 25.9% of cases. Patients with inactive cysts on ultrasound but positive serological tests were also investigated by CT scan (chest and abdomen) to rule out extra-hepatic cyst localization. This study confirms the importance of a stage-specific approach to the management of cystic echinococcosis and supports the use of a monitoring-only approach to inactive, uncomplicated cysts of the liver. It also confirms that serology plays only an ancillary role in the clinical management of these patients, compared to ultrasound and other imaging techniques. The implications of these findings for clinical management and natural history of cystic echinococcosis are discussed. 相似文献
80.
Aikaterini Vergetaki Udo Jeschke Thomas Vrekoussis Eirini Taliouri Luca Sabatini Evangelia A. Papakonstanti Antonis Makrigiannakis 《PloS one》2013,8(4)
Endometriosis is considered as a benign aseptic inflammatory disease, characterised by the presence of ectopic endometrium-like tissue. Its symptoms (mostly pain and infertility) are reported as constant stressors. Corticotropin releasing hormone (CRH) and urocortin (UCN) are neuropeptides, strongly related to stress and inflammation. The effects of CRH and UCN are mediated through CRHR1 and CRHR2 receptors which are implicated in several reproductive functions acting as inflammatory components. However, the involvement of these molecules to endometriosis remains unknown. The aim of this study was to examine the expression of CRHR1 and CRHR2 in endometriotic sites and to compare the expression of CRHR1 and CRHR2 in eutopic endometrium of endometriotic women to that of healthy women. We further compared the expression of CRH, UCN, CRHR1 and CRHR2 in ectopic endometrium to that in eutopic endometrium of women with endometriosis. Endometrial biopsy specimens were taken from healthy women (10 patients) and endometrial and endometriotic biopsy specimens were taken from women with endometriosis (16 patients). Τhe expression of CRH, UCN, CRHR1, and CRHR2 was tested via RT-PCR, immunohistochemistry and Western blotting. This study shows for the first time that CRH and UCN receptor subtypes CRHR1β and CRHR2α are expressed in endometriotic sites and that they are more strongly expressed (p<0.01) in eutopic endometrium of women with endometriosis compared to healthy women endometrium at the mRNA and protein level. CRH, UCN, CRHR1 and CRHR2 mRNA were also more highly expressed in ectopic rather than eutopic endometrium (CRH, UCN, CRHR2α: p<0.01, CRHR1β: p<0.05) and protein (CRH and UCN: p<0.05, CRHR1 and CRHR2: p<0.01) in women with endometriosis. These data indicate that CRH and UCN might play an immunoregulatory role in endometriotic sites by affecting reproductive functions such as decidualization and implantation of women with endometriosis. 相似文献