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81.
Studer B Boller B Bauer E Posselt UK Widmer F Kölliker R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(1):9-17
Crown rust, caused by Puccinia coronata f. sp. lolii, is one of the most important diseases of temperate forage grasses, such as ryegrasses (Lolium spp.), affecting yield and nutritional quality. Therefore, resistance to crown rust is a major goal in ryegrass breeding
programmes. In a two-way pseudo-testcross population consisting of 306 Lolium multiflorum individuals, multisite field evaluations as well as alternative methods based on artificial inoculation with natural inoculate
in controlled environments were used to identify QTLs controlling resistance to crown rust. Disease scores obtained from glasshouse
and leaf segment test (LST) evaluations were highly correlated with scores from a multisite field assessment (r = 0.66 and 0.79, P < 0.01, respectively) and thus confirmed suitability of these methods for crown rust investigations. Moreover, QTL mapping
based on a linkage map consisting of 368 amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers
revealed similar results across different phenotyping methods. Two major QTLs were consistently detected on linkage group
(LG) 1 and LG 2, explaining up to 56% of total phenotypic variance (V
p). Nevertheless, differences between position and magnitude of QTLs were observed among individual field locations and suggested
the existence of specific local pathogen populations. The present study not only compared QTL results among crown rust evaluation
methods and environments, but also identified molecular markers closely linked to previously undescribed QTLs for crown rust
resistance in Italian ryegrass with the potential to be applied in marker-assisted forage crop breeding.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
82.
Paolo Cossu-Rocca Sandra Orrù Maria Rosaria Muroni Francesca Sanges Giovanni Sotgiu Sara Ena Giovanna Pira Luciano Murgia Alessandra Manca Maria Gabriela Uras Maria Giuseppina Sarobba Silvana Urru Maria Rosaria De Miglio 《PloS one》2015,10(11)
Background
Triple Negative Breast Cancer (TNBC) accounts for 12–24% of all breast carcinomas, and shows worse prognosis compared to other breast cancer subtypes. Molecular studies demonstrated that TNBCs are a heterogeneous group of tumors with different clinical and pathologic features, prognosis, genetic-molecular alterations and treatment responsivity. The PI3K/AKT is a major pathway involved in the regulation of cell survival and proliferation, and is the most frequently altered pathway in breast cancer, apparently with different biologic impact on specific cancer subtypes. The most common genetic abnormality is represented by PIK3CA gene activating mutations, with an overall frequency of 20–40%. The aims of our study were to investigate PIK3CA gene mutations on a large series of TNBC, to perform a wider analysis on genetic alterations involving PI3K/AKT and BRAF/RAS/MAPK pathways and to correlate the results with clinical-pathologic data.Materials and Methods
PIK3CA mutation analysis was performed by using cobas® PIK3CA Mutation Test. EGFR, AKT1, BRAF, and KRAS genes were analyzed by sequencing. Immunohistochemistry was carried out to identify PTEN loss and to investigate for PI3K/AKT pathways components.Results
PIK3CA mutations were detected in 23.7% of TNBC, whereas no mutations were identified in EGFR, AKT1, BRAF, and KRAS genes. Moreover, we observed PTEN loss in 11.3% of tumors. Deregulation of PI3K/AKT pathways was revealed by consistent activation of pAKT and p-p44/42 MAPK in all PIK3CA mutated TNBC.Conclusions
Our data shows that PIK3CA mutations and PI3K/AKT pathway activation are common events in TNBC. A deeper investigation on specific TNBC genomic abnormalities might be helpful in order to select patients who would benefit from current targeted therapy strategies. 相似文献83.
84.
Giovanni Bacci Patrizia Paganin Loredana Lopez Chiara Vanni Claudia Dalmastri Cristina Cantale Loretta Daddiego Gaetano Perrotta Daniela Dolce Patrizia Morelli Vanessa Tuccio Alessandra De Alessandri Ersilia Vita Fiscarelli Giovanni Taccetti Vincenzina Lucidi Annamaria Bevivino Alessio Mengoni 《PloS one》2016,11(6)
Chronic airway infection is a hallmark feature of cystic fibrosis (CF) disease. In the present study, sputum samples from CF patients were collected and characterized by 16S rRNA gene-targeted approach, to assess how lung microbiota composition changes following a severe decline in lung function. In particular, we compared the airway microbiota of two groups of patients with CF, i.e. patients with a substantial decline in their lung function (SD) and patients with a stable lung function (S). The two groups showed a different bacterial composition, with SD patients reporting a more heterogeneous community than the S ones. Pseudomonas was the dominant genus in both S and SD patients followed by Staphylococcus and Prevotella. Other than the classical CF pathogens and the most commonly identified non-classical genera in CF, we found the presence of the unusual anaerobic genus Sneathia. Moreover, the oligotyping analysis revealed the presence of other minor genera described in CF, highlighting the polymicrobial nature of CF infection. Finally, the analysis of correlation and anti-correlation networks showed the presence of antagonism and ecological independence between members of Pseudomonas genus and the rest of CF airways microbiota, with S patients showing a more interconnected community in S patients than in SD ones. This population structure suggests a higher resilience of S microbiota with respect to SD, which in turn may hinder the potential adverse impact of aggressive pathogens (e.g. Pseudomonas). In conclusion, our findings shed a new light on CF airway microbiota ecology, improving current knowledge about its composition and polymicrobial interactions in patients with CF. 相似文献
85.
Donatella Marazziti Lionella Palego Chiara Mazzanti Stefano Silvestri Giovanni B. Cassano 《Chronobiology international》1995,12(2):100-105
Our study aimed to investigate the possible presence of seasonal changes in platelet phenolsulfotransferase (ST) in a group of 20 healthy, drug-free subjects of both sexes and between 24 and 37 years of age. Blood samples were taken four times a year in the period immediately following the equinoxes and the solstices. The results showed that both STs underwent seasonal changes: the lowest values were found in autumn and in winter, and the highest in the summer. A positive correlation between the two STs and the length of the photoperiod was observed in winter, whereas in the spring we detected a negative correlation between the TL ST and the photoperiod length. Future studies should clarify whether platelet ST of patients with mood disorders shows a similar seasonality. 相似文献
86.
Claudio Pulito Irene Terrenato Anna Di Benedetto Etleva Korita Frauke Goeman Andrea Sacconi Francesca Biagioni Giovanni Blandino Sabrina Strano Paola Muti Marcella Mottolese Elisabetta Falvo 《PloS one》2015,10(4)
Vitamin D plays a role in cancer development and acts through the vitamin D receptor (VDR). It regulates the action of hormone responsive genes and is involved in cell cycle regulation, differentiation and apoptosis. VDR is a critical component of the vitamin D pathway and different common single nucleotide polymorphisms have been identified. Cdx2 VDR polymorphism can play an important role in breast cancer, modulating the activity of VDR. The objective of this study is to assess the relationship between the Cdx2 VDR polymorphism and the activities of VDR in human breast cancer cell lines and carcinomas breast patients. Cdx2 VDR polymorphism and antiproliferative effects of vitamin D treatment were investigated in a panel of estrogen receptor-positive (MCF7 and T-47D) and estrogen receptor-negative (MDA-MB-231, SUM 159PT, SK-BR-3, BT549, MDA-MB-468, HCC1143, BT20 and HCC1954) human breast cancer cell lines. Furthermore, the potential relationship among Cdx2 VDR polymorphism and a number of biomarkers used in clinical management of breast cancer was assessed in an ad hoc set of breast cancer cases. Vitamin D treatment efficacy was found to be strongly dependent on the Cdx2 VDR status in ER-negative breast cancer cell lines tested. In our series of breast cancer cases, the results indicated that patients with variant homozygote AA were associated with bio-pathological characteristics typical of more aggressive tumours, such as ER negative, HER2 positive and G3. Our results may suggest a potential effect of Cdx2 VDR polymorphism on the efficacy of vitamin D treatment in aggressive breast cancer cells (estrogen receptor negative). These results suggest that Cdx2 polymorphism may be a potential biomarker for vitamin D treatment in breast cancer, independently of the VDR receptor expression. 相似文献
87.
Beryl Royer-Bertrand Matteo Torsello Donata Rimoldi Ikram El Zaoui Katarina Cisarova Rosanna Pescini-Gobert Franck Raynaud Leonidas Zografos Ann Schalenbourg Daniel Speiser Michael Nicolas Laureen Vallat Robert Klein Serge Leyvraz Giovanni Ciriello Nicolò Riggi Alexandre P. Moulin Carlo Rivolta 《American journal of human genetics》2016,99(5):1190-1198
88.
Thaís C. Lima Rodrigo Lucarini Angelica C. Volpe Carolina Q.J. de Andrade Alice M.P. Souza Patricia M. Pauletti Ana H. Januário Guilherme V. Símaro Jairo K. Bastos Wilson R. Cunha Alexandre Borges Rosangela da Silva Laurentiz Valéria A. Conforti Renato L.T. Parreira Carly H.G. Borges Giovanni F. Caramori Karla F. Andriani Márcio L.A. e Silva 《Bioorganic & medicinal chemistry letters》2017,27(2):176-179
(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK. 相似文献
89.
Giorgia M Siriaco Giovanni Cenci Abdelali Haoudi Larry E Champion Chun Zhou Maurizio Gatti James M Mason 《Genetics》2002,160(1):235-245
In most eukaryotes telomeres are extended by telomerase. Drosophila melanogaster, however, lacks telomerase, and telomere-specific non-LTR retrotransposons, HeT-A and TART, transpose specifically to chromosome ends. A Drosophila strain, Gaiano, that has long telomeres has been identified. We extracted the major Gaiano chromosomes into an Oregon-R genetic background and examined the resulting stocks after 60 generations. In situ hybridization using HeT-A and TART sequences showed that, in stocks carrying either the X or the second chromosome from Gaiano, only the Gaiano-derived chromosomes display long telomeres. However, in stocks carrying the Gaiano third chromosome, all telomeres are substantially elongated, indicating that the Gaiano chromosome 3 carries a factor that increases HeT-A and TART addition to the telomeres. We show that this factor, termed Telomere elongation (Tel), is dominant and localizes as a single unit to 69 on the genetic map. The long telomeres tend to associate with each other in both polytene and mitotic cells. These associations depend on telomere length rather than the presence of Tel. Associations between metaphase chromosomes are resolved during anaphase, suggesting that they are mediated by either proteinaceous links or DNA hydrogen bonding, rather than covalent DNA-DNA bonds. 相似文献
90.
By lyophilizing RNase A from 40% acetic acid solutions, two dimeric aggregates, the "minor" and "major" dimers (named here N-dimer and C-dimer, respectively), form by 3D domain swapping at a ratio of 1:4. Trimeric and tetrameric aggregates are also obtained. The two dimers and the higher oligomers also form without a lyophilization step. By keeping RNase A dissolved at a high concentration (generally 200 mg/ml) in various media at temperatures ranging from 23 to 70 degrees C for times varying from a few minutes to 2 h, various oligomers, in particular the two dimeric conformers, formed in quite different amounts, often inverting their relative quantities depending on the more or less severe unfolding conditions. When unfolding mainly concerned the N terminus of the protein, richer in hydrophilic residues, the N-dimer, formed by 3D domain swapping of the N-terminal alpha-helix of each monomer, prevailed over the C-dimer. Under more vigorous denaturing conditions, where also the C terminus of RNase A, richer in hydrophobic amino acids, unfolded, the C-dimer, formed by 3D domain swapping of the C-terminal beta-strand, prevailed over the other, possibly because of the induction to aggregation promoted by the hydrophobic residues present in the C termini of the two monomers. 相似文献