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1.
Barrera Lawrence N. Ridley P. Matthew Bermejo-Rodriguez Camino Costello Eithne Perez-Mancera Pedro A. 《Journal of physiology and biochemistry》2023,79(1):193-204
Journal of Physiology and Biochemistry - Pancreatic ductal adenocarcinoma (PDAC) is the deadliest of the common cancers. A major hallmark of PDAC is an abundant and dense fibrotic stroma, the... 相似文献
2.
María Prez-Caro Csar Cobaleda Ins Gonzlez-Herrero Carolina Vicente-Dueas Camino Bermejo-Rodríguez Margarita Snchez-Beato Alberto Orfao Beln Pintado Teresa Flores Manuel Snchez-Martín Rafael Jimnez Miguel A Piris Isidro Snchez-García 《The EMBO journal》2009,28(1):8-20
In human cancers, all cancerous cells carry the oncogenic genetic lesions. However, to elucidate whether cancer is a stem cell-driven tissue, we have developed a strategy to limit oncogene expression to the stem cell compartment in a transgenic mouse setting. Here, we focus on the effects of the BCR-ABLp210 oncogene, associated with chronic myeloid leukaemia (CML) in humans. We show that CML phenotype and biology can be established in mice by restricting BCR-ABLp210 expression to stem cell antigen 1 (Sca1)+ cells. The course of the disease in Sca1-BCR-ABLp210 mice was not modified on STI571 treatment. However, BCR-ABLp210-induced CML is reversible through the unique elimination of the cancer stem cells (CSCs). Overall, our data show that oncogene expression in Sca1+ cells is all that is required to fully reprogramme it, giving rise to a full-blown, oncogene-specified tumour with all its mature cellular diversity, and that elimination of the CSCs is enough to eradicate the whole tumour. 相似文献
3.
Effects of nutrients and fish on periphyton and plant biomass across a European latitudinal gradient
Eloy Bécares Joan Gomá Margarita Fernández-Aláez Camino Fernández-Aláez Susana Romo Maria R. Miracle Anika Ståhl-Delbanco Lars-Anders Hansson Mykael Gyllström Wouter J. Van de Bund Ellen Van Donk Timo Kairesalo Jaana Hietala Debbie Stephen David Balayla Brian Moss 《Aquatic Ecology》2008,42(4):561-574
Replicated, factorial mesocosm experiments were conducted across Europe to study the effects of nutrient enrichment and fish
density on macrophytes and on periphyton chlorophyll a (chl-a) with regard to latitude. Periphyton chl-a densities and plant decline were significantly related to nutrient loading in all countries. Fish effects were significant
in a few sites only, mostly because of their contribution to the nutrient pool. A saturation-response type curve in periphyton
chl-a with nutrients was found, and northern lakes achieved higher densities than southern lakes. Nutrient concentration and phytoplankton
chl-a necessary for a 50% plant reduction followed a latitudinal gradient. Total phosphorus values for 50% plant disappearance
were similar from Sweden (0.27 mg L−1) to northern Spain (0.35 mg L−1), but with a sharp increase in southern Spain (0.9 mg L−1). Planktonic chl-a values for 50% plant reduction increased monotonically from Sweden (30 μg L−1) to València (150 μg L−1). Longer plant growing-season, higher light intensities and temperature, and strong water-level fluctuations characteristic
of southern latitudes can lead to greater persistence of macrophyte biomass at higher turbidities and nutrient concentration
than in northern lakes. Results support the evidence that latitudinal differences in the functioning of shallow lakes should
be considered in lake management and conservation policies. 相似文献
4.
Kristina Kirschner Shamith A. Samarajiwa Jonathan M. Cairns Suraj Menon Pedro A. Pérez-Mancera Kosuke Tomimatsu Camino Bermejo-Rodriguez Yoko Ito Tamir Chandra Masako Narita Scott K. Lyons Andy G. Lynch Hiroshi Kimura Tetsuya Ohbayashi Simon Tavaré Masashi Narita 《PLoS genetics》2015,11(3)
The downstream functions of the DNA binding tumor suppressor p53 vary depending on the cellular context, and persistent p53 activation has recently been implicated in tumor suppression and senescence. However, genome-wide information about p53-target gene regulation has been derived mostly from acute genotoxic conditions. Using ChIP-seq and expression data, we have found distinct p53 binding profiles between acutely activated (through DNA damage) and chronically activated (in senescent or pro-apoptotic conditions) p53. Compared to the classical ‘acute’ p53 binding profile, ‘chronic’ p53 peaks were closely associated with CpG-islands. Furthermore, the chronic CpG-island binding of p53 conferred distinct expression patterns between senescent and pro-apoptotic conditions. Using the p53 targets seen in the chronic conditions together with external high-throughput datasets, we have built p53 networks that revealed extensive self-regulatory ‘p53 hubs’ where p53 and many p53 targets can physically interact with each other. Integrating these results with public clinical datasets identified the cancer-associated lipogenic enzyme, SCD, which we found to be directly repressed by p53 through the CpG-island promoter, providing a mechanistic link between p53 and the ‘lipogenic phenotype’, a hallmark of cancer. Our data reveal distinct phenotype associations of chronic p53 targets that underlie specific gene regulatory mechanisms. 相似文献
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6.
Gryllophila cephalobulata n. sp. (Nematoda, Thelastomatidae) a parasite of the mole cricket Neocurtilla claraziana (Orthoptera, Gryllotalpidae) isolated in Buenos Aires Province, is described and illustrated. It is characterized by cuticle annulated all along the length of the body; the first ring has 4 lobules, the second one has 14 lobules, the others rings are simple, the stoma is short and has 4 small teeth, the genital papillae are arranged in 5 pairs, of which 3 pairs are preanal and 2 pairs are postanal. The tail appendage of the male is long and filiform. 相似文献
7.
Cephalobium odontolateralis n. sp. (Nematoda, Cephalobiidae) is described and illustrated from the nymphs of Anurogryllus muticus (De Geer) (Orthoptera, Gryllidae) from Buenos Aires province, Argentina. It is characterized by a lateral large tooth in the stoma and by the arrangement and number of the genital papillae in the male; there are 6 pairs of postanal papillae, but none is preanal. 相似文献
8.
García Fontán MC Franco I Tornadijo ME Carballo J 《Acta microbiologica et immunologica Hungarica》2002,49(1):119-128
A comparison of the results obtained using the classical methods with those of the API 20 Strep system was carried out in identifying 24 enterococci strains isolated from San Simón cow's milk cheese, a traditional Spanish variety. The results of both identification systems coincided exactly in 9 strains (37.5% of the strains studied). In one strain the results obtained using the classical methods did not coincide with those using the API 20 Strep method. 3 strains (12.5%) could not be identified using the API 20 Strep system. However, 11 strains (45%), that remained doubtful between both species E. faecalis and E. faecium on the basis of the classical methods, were identified using the API 20 Strep system. The API 20 Strep system does not include some biochemical tests of importance in identifying of foodborne enterococci and could not identify the atypical strains of Enterococcus. Moreover, this system is adapted to the identification of enterococci of clinical origin and their database does not include some species common in foods. However, it could have an application in combination with the classical methods in order to carry out a reasonably rapid and reliable identification of enterococci related to cheese. 相似文献
9.
Anne E. Carlson Lindsey A. Burnett Donato del Camino Timothy A. Quill Bertil Hille Jayhong A. Chong Magdalene M. Moran Donner F. Babcock 《PloS one》2009,4(8)
The four sperm-specific CatSper ion channel proteins are required for hyperactivated motility and male fertility, and for Ca2+ entry evoked by alkaline depolarization. In the absence of external Ca2+, Na+ carries current through CatSper channels in voltage-clamped sperm. Here we show that CatSper channel activity can be monitored optically with the [Na+]i-reporting probe SBFI in populations of intact sperm. Removal of external Ca2+ increases SBFI signals in wild-type but not CatSper2-null sperm. The rate of the indicated rise of [Na+]i is greater for sperm alkalinized with NH4Cl than for sperm acidified with propionic acid, reflecting the alkaline-promoted signature property of CatSper currents. In contrast, the [Na+]i rise is slowed by candidate CatSper blocker HC-056456 (IC50 ∼3 µM). HC-056456 similarly slows the rise of [Ca2+]i that is evoked by alkaline depolarization and reported by fura-2. HC-056456 also selectively and reversibly decreased CatSper currents recorded from patch-clamped sperm. HC-056456 does not prevent activation of motility by HCO3
− but does prevent the development of hyperactivated motility by capacitating incubations, thus producing a phenocopy of the CatSper-null sperm. When applied to hyperactivated sperm, HC-056456 causes a rapid, reversible loss of flagellar waveform asymmetry, similar to the loss that occurs when Ca2+ entry through the CatSper channel is terminated by removal of external Ca2+. Thus, open CatSper channels and entry of external Ca2+ through them sustains hyperactivated motility. These results indicate that pharmacological targeting of the CatSper channel may impose a selective late-stage block to fertility, and that high-throughput screening with an optical reporter of CatSper channel activity may identify additional selective blockers with potential for male-directed contraception. 相似文献
10.
Characterization and biological role of the O-polysaccharide gene cluster of Yersinia enterocolitica serotype O:9 下载免费PDF全文
Skurnik M Biedzka-Sarek M Lübeck PS Blom T Bengoechea JA Pérez-Gutiérrez C Ahrens P Hoorfar J 《Journal of bacteriology》2007,189(20):7244-7253
Yersinia enterocolitica serotype O:9 is a gram-negative enteropathogen that infects animals and humans. The role of lipopolysaccharide (LPS) in Y. enterocolitica O:9 pathogenesis, however, remains unclear. The O:9 LPS consists of lipid A to which is linked the inner core oligosaccharide, serving as an attachment site for both the outer core (OC) hexasaccharide and the O-polysaccharide (OPS; a homopolymer of N-formylperosamine). In this work, we cloned the OPS gene cluster of O:9 and identified 12 genes organized into four operons upstream of the gnd gene. Ten genes were predicted to encode glycosyltransferases, the ATP-binding cassette polysaccharide translocators, or enzymes required for the biosynthesis of GDP-N-formylperosamine. The two remaining genes within the OPS gene cluster, galF and galU, were not ascribed a clear function in OPS biosynthesis; however, the latter gene appeared to be essential for O:9. The biological functions of O:9 OPS and OC were studied using isogenic mutants lacking one or both of these LPS parts. We showed that OPS and OC confer resistance to human complement and polymyxin B; the OPS effect on polymyxin B resistance could be observed only in the absence of OC. 相似文献