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731.
732.
Nuno P. Mira Martin Münsterk?tter Filipa Dias-Valada Júlia Santos Margarida Palma Filipa C. Roque Joana F. Guerreiro Fernando Rodrigues Maria Jo?o Sousa Cecília Le?o Ulrich Güldener Isabel Sá-Correia 《DNA research》2014,21(3):299-313
In this work, it is described the sequencing and annotation of the genome of the yeast strain ISA1307, isolated from a sparkling wine continuous production plant. This strain, formerly considered of the Zygosaccharomyces bailii species, has been used to study Z. bailii physiology, in particular, its extreme tolerance to acetic acid stress at low pH. The analysis of the genome sequence described in this work indicates that strain ISA1307 is an interspecies hybrid between Z. bailii and a closely related species. The genome sequence of ISA1307 is distributed through 154 scaffolds and has a size of around 21.2 Mb, corresponding to 96% of the genome size estimated by flow cytometry. Annotation of ISA1307 genome includes 4385 duplicated genes (∼90% of the total number of predicted genes) and 1155 predicted single-copy genes. The functional categories including a higher number of genes are ‘Metabolism and generation of energy’, ‘Protein folding, modification and targeting’ and ‘Biogenesis of cellular components’. The knowledge of the genome sequence of the ISA1307 strain is expected to contribute to accelerate systems-level understanding of stress resistance mechanisms in Z. bailii and to inspire and guide novel biotechnological applications of this yeast species/strain in fermentation processes, given its high resilience to acidic stress. The availability of the ISA1307 genome sequence also paves the way to a better understanding of the genetic mechanisms underlying the generation and selection of more robust hybrid yeast strains in the stressful environment of wine fermentations. 相似文献
733.
Júlio Santos Maria Jo?o Gouveia Nuno Vale Maria de Lurdes Delgado Ana Gon?alves José M. Teixeira. da Silva Cristiano Oliveira Pedro Xavier Paula Gomes Lúcio L. Santos Carlos Lopes Alberto Barros Gabriel Rinaldi Paul J. Brindley José M. Correia da Costa Mário Sousa Mónica C. Botelho 《PloS one》2014,9(5)
Background
Schistosomiasis is a neglected tropical disease, endemic in 76 countries, that afflicts more than 240 million people. The impact of schistosomiasis on infertility may be underestimated according to recent literature. Extracts of Schistosoma haematobium include estrogen-like metabolites termed catechol-estrogens that down regulate estrogen receptors alpha and beta in estrogen responsive cells. In addition, schistosome derived catechol-estrogens induce genotoxicity that result in estrogen-DNA adducts. These catechol estrogens and the catechol-estrogen-DNA adducts can be isolated from sera of people infected with S. haematobium. The aim of this study was to study infertility in females infected with S. haematobium and its association with the presence of schistosome-derived catechol-estrogens.Methodology/Principal Findings
A cross-sectional study was undertaken of female residents of a region in Bengo province, Angola, endemic for schistosomiasis haematobia. Ninety-three women and girls, aged from two (parents interviewed) to 94 years were interviewed on present and previous urinary, urogenital and gynecological symptoms and complaints. Urine was collected from the participants for egg-based parasitological assessment of schistosome infection, and for liquid chromatography diode array detection electron spray ionization mass spectrometry (LC/UV-DAD/ESI-MSn) to investigate estrogen metabolites in the urine. Novel estrogen-like metabolites, potentially of schistosome origin, were detected in the urine of participants who were positive for eggs of S. haematobium, but not detected in urines negative for S. haematobium eggs. The catechol-estrogens/ DNA adducts were significantly associated with schistosomiasis (OR 3.35; 95% CI 2.32–4.84; P≤0.001). In addition, presence of these metabolites was positively associated with infertility (OR 4.33; 95% CI 1.13–16.70; P≤0.05).Conclusions/Significance
Estrogen metabolites occur widely in diverse metabolic pathways. In view of the statistically significant association between catechol-estrogens/ DNA adducts and self-reported infertility, we propose that an estrogen-DNA adduct mediated pathway in S. haematobium-induced ovarian hormonal deregulation could be involved. In addition, the catechol-estrogens/ DNA adducts described here represent potential biomarkers for schistosomiasis haematobia. 相似文献734.
Keisuke Ishizawa Yuki Izawa-Ishizawa Noriko Yamano Maki Urushihara Takumi Sakurada Masaki Imanishi Shoko Fujii Asami Nuno Licht Miyamoto Yoshitaka Kihira Yasumasa Ikeda Shoji Kagami Hiroyuki Kobori Koichiro Tsuchiya Toshiaki Tamaki 《PloS one》2014,9(1)
Diabetic nephropathy (DN) is the major cause of end-stage renal failure. Oxidative stress is implicated in the pathogenesis of DN. Nitrosonifedipine (NO-NIF) is a weak calcium channel blocker that is converted from nifedipine under light exposure. Recently, we reported that NO-NIF has potential as a novel antioxidant with radical scavenging abilities and has the capacity to treat vascular dysfunction by exerting an endothelial protective effect. In the present study, we extended these findings by evaluating the efficacy of NO-NIF against DN and by clarifying the mechanisms of its antioxidative effect. In a model of type 2 DN (established in KKAy mice), NO-NIF administration reduced albuminuria and proteinuria as well as glomerular expansion without affecting glucose metabolism or systolic blood pressure. NO-NIF also suppressed renal and systemic oxidative stress and decreased the expression of intercellular adhesion molecule (ICAM)-1, a marker of endothelial cell injury, in the glomeruli of the KKAy mice. Similarly, NO-NIF reduced albuminuria, oxidative stress, and ICAM-1 expression in endothelial nitric oxide synthase (eNOS) knockout mice. Moreover, NO-NIF suppressed urinary angiotensinogen (AGT) excretion and intrarenal AGT protein expression in proximal tubular cells in the KKAy mice. On the other hand, hyperglycemia-induced mitochondrial superoxide production was not attenuated by NO-NIF in cultured endothelial cells. These findings suggest that NO-NIF prevents the progression of type 2 DN associated with endothelial dysfunction through selective antioxidative effects. 相似文献
735.
Nicolás Vite-García Olivia Arjona Enrique Morales-Bojorquez Maite Mascaro Nuno Simoes 《Marine and Freshwater Behaviour and Physiology》2014,47(6):401-413
There is a worldwide interest in seahorse culture to protect wild populations from human predation for aquaria and to establish an industry in developing countries. This study was undertaken to gather information on the lipid and fatty acid status of wild caught seahorses to inform the development of aquarium diets. Brood size, lipid classes, fatty acids, and pigments were analyzed in newborn Hippocampus erectus juveniles from recently captured pregnant wild males during January–March 2009–2010. The lipids of newborn seahorses are composed of phospholipids (mean 75–80%), free cholesterol (8–10%), cholesterol esters (4–9%), and acylglycerides (3–11%). The main pigments were total carotenoids (mean 58–79 µg/g). The most abundant fatty acids in newborn seahorses were 22:6n-3 (21–27%) and 20:4n-6 (7–9%). Both were higher than levels reported in other seahorses. A factor analysis showed that PC1 (48.7% of variation) was composed of the three main highly unsaturated fatty acids: 20:4n-6, 20:5n-3 and a negative contribution of 22:6n-3. PC2 contributed 18:5n-3 and several branched fatty acids. PC3 contributed 18:2n-6 and 18:3n-3. Each of these three components correlated with different environmental factors. The results suggested that high levels of 22:6n-3 rather than 20:5n-3 could increase juvenile survival and assist them to tolerate salinity changes better. The results also suggest that a diet of live prey enriched with 22:6n-3 would be likely to increase the growth and survival in captivity, at least for this species. 相似文献
736.
Bruno Maia‐Carvalho Helena Gonalves Iigo Martínez‐Solano Jorge Gutirrez‐Rodríguez Susana Lopes Nuno Ferrand Fernando Sequeira 《Journal of Zoological Systematics and Evolutionary Research》2014,52(2):170-175
The common midwife toad (Alytes obstetricans), widely distributed in the northern half of the Iberian Peninsula and part of Western Europe, is currently subdivided into four subspecies: A. o. obstetricans, A. o. boscai, A. o. pertinax and A. o. almogavarii. However, the delimitation of these subspecies and their ranges are still under discussion because strong discordances have been found between morphological and molecular data, and especially among different genetic markers. Here, we screen a set of novel microsatellite loci and mtDNA sequences of A. obstetricans populations representative of all currently recognized subspecies to investigate the correspondence between genetic groupings inferred from clustering analysis of microsatellite genotypes and the described subspecies and test whether patterns of mtDNA variation are concordant with those genetic clusters. Our results confirm previous expectations of extremely high intraspecific diversity in A. obstetricans in Iberia. Analyses of microsatellite and mtDNA data were concordant in recovering five well‐defined groups, of which three correspond to previously defined subspecies, while the two additional clusters correspond to populations of subspecies A. o. boscai separated by the Douro River. Our results suggest the occurrence of two distinct genetic units within A. o. boscai that likely result from a long independent evolutionary history, thus deserving special attention from a conservation point of view. 相似文献
737.
Fernando A. Seixas Javier Juste Paula F. Campos Miguel Carneiro Nuno Ferrand Paulo C. Alves José Melo‐Ferreira 《Biological journal of the Linnean Society. Linnean Society of London》2014,111(4):748-760
The Mediterranean islands have a long history of human‐mediated introductions resulting in frequent replacements of their fauna and flora. Although these histories are sometimes well documented or may be inferred from paleontological studies, the use of phylogenetic and population genetic reconstruction methods provides a complementary perspective for answering questions related to the history of insular species. In the present study, we infer the colonization history of Mallorca (Balearic Islands) by the European rabbit (Oryctolagus cuniculus) and the Iberian hare (Lepus granatensis) using sequence variation of the mitochondrial DNA control region from continental and insular specimens (total of 489 sequences). Additionally, the taxonomic identity of Mallorcan L. granatensis was confirmed using a diagnostic nuclear marker. For both Mallorcan rabbits and hares, genetic diversity was comparable to the continental populations, suggesting the introduction of multiple lineages. Two Mallorcan haplogroups were found in hares, which likely correspond to two introduction events. Rabbits from Mallorca were identified as belonging to the subspecies Oryctolagus cuniculus cuniculus, and may have been originated both from Iberian and French populations. The molecular estimates of the timing of the colonization events of the Mallorcan lagomorphs are consistent with human‐mediated introductions by early settlers on the islands. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 748–760. 相似文献
738.
Thomas Girin Pauline Stephenson Cassandra M. P. Goldsack Sherry A. Kempin Amandine Perez Nuno Pires Penelope A. Sparrow Thomas A. Wood Martin F. Yanofsky Lars Østergaard 《The Plant journal : for cell and molecular biology》2010,63(2):329-338
Members of the Brassicaceae family, including Arabidopsis thaliana and oilseed rape (Brassica napus), produce dry fruits that open upon maturity along a specialised tissue called the valve margin. Proper development of the valve margin in Arabidopsis is dependent on the INDEHISCENT (IND) gene, the role of which in genetic and hormonal regulation has been thoroughly characterised. Here we perform phylogenetic comparison of IND genes in Arabidopsis and Brassica to identify conserved regulatory sequences that are responsible for specific expression at the valve margin. In addition we have taken a comparative development approach to demonstrate that the BraA.IND.a and BolC.IND.a genes from B. rapa and B. oleracea share identical function with Arabidopsis IND since ethyl methanesulphonate (EMS) mutant alleles and silenced transgenic lines have valve margin defects. Furthermore we show that the degree of these defects can be fine‐tuned for crop improvement. Wild‐type Arabidopsis produces an outer replum composed of about six cell files at the medial region of the fruits, whereas Brassica fruits lack this tissue. A strong loss‐of‐function braA.ind.a mutant gained outer replum tissue in addition to its defect in valve margin development. An enlargement of replum size was also observed in the Arabidopsis ind mutant suggesting a general role of Brassicaceae IND genes in preventing valve margin cells from adopting replum identity. 相似文献
739.
Nuno P Mira Margarida Palma Joana F Guerreiro Isabel Sá-Correia 《Microbial cell factories》2010,9(1):79
Background
Acetic acid is a byproduct of Saccharomyces cerevisiae alcoholic fermentation. Together with high concentrations of ethanol and other toxic metabolites, acetic acid may contribute to fermentation arrest and reduced ethanol productivity. This weak acid is also a present in lignocellulosic hydrolysates, a highly interesting non-feedstock substrate in industrial biotechnology. Therefore, the better understanding of the molecular mechanisms underlying S. cerevisiae tolerance to acetic acid is essential for the rational selection of optimal fermentation conditions and the engineering of more robust industrial strains to be used in processes in which yeast is explored as cell factory. 相似文献740.
Teschendorff AE Naderi A Barbosa-Morais NL Caldas C 《Bioinformatics (Oxford, England)》2006,22(18):2269-2275
MOTIVATION: Elucidating the molecular taxonomy of cancers and finding biological and clinical markers from microarray experiments is problematic due to the large number of variables being measured. Feature selection methods that can identify relevant classifiers or that can remove likely false positives prior to supervised analysis are therefore desirable. RESULTS: We present a novel feature selection procedure based on a mixture model and a non-gaussianity measure of a gene's expression profile. The method can be used to find genes that define either small outlier subgroups or major subdivisions, depending on the sign of kurtosis. The method can also be used as a filtering step, prior to supervised analysis, in order to reduce the false discovery rate. We validate our methodology using six independent datasets by rediscovering major classifiers in ER negative and ER positive breast cancer and in prostate cancer. Furthermore, our method finds two novel subtypes within the basal subgroup of ER negative breast tumours, associated with apoptotic and immune response functions respectively, and with statistically different clinical outcome. AVAILABILITY: An R-function pack that implements the methods used here has been added to vabayelMix, available from (www.cran.r-project.org). CONTACT: aet21@cam.ac.uk SUPPLEMENTARY INFORMATION: Supplementary information is available at Bioinformatics online. 相似文献