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61.
Since the publication of our article (Roth, Gonnet, and Dessimoz: BMC Bioinformatics 2008 9: 518), we have noticed several errors, which we correct in the following. 相似文献
62.
Felipe Otálvaro Kusuma Jitsaeng Tobias Munde Fernando Echeverri Winston Quiñones Bernd Schneider 《Phytochemistry》2010,71(2-3):206-213
Biosynthetic O-methylation at various sites along the backbone of inducible phenylphenalenones in Musa acuminata var. “Williams” (Musaceae) and Wachendorfia thyrsiflora (Haemodoraceae) was investigated using 13C-labelled precursors. The inducibility of O-methylated metabolites was demonstrated in both species and the origin of methoxyl group from [methyl-13C]l-methionine was confirmed. In addition to known phenylphenalenones, a methoxylated metabolite, 4-(4-hydroxy-3-methoxy-phenyl)-benzo[de]isochromene-1,3-dione, was detected and its structure elucidated mainly by NMR spectroscopic techniques. The experiments were used to discriminate methionine-derived and artificial methoxy groups formed during methanolic extraction. Finally, demethylation of 4′-methoxycinnamic acid and subsequent conversion to 3′,4′-methylenedioxycinnamic acid was demonstrated in M. acuminata. 相似文献
63.
Echeverri CJ Beachy PA Baum B Boutros M Buchholz F Chanda SK Downward J Ellenberg J Fraser AG Hacohen N Hahn WC Jackson AL Kiger A Linsley PS Lum L Ma Y Mathey-Prévôt B Root DE Sabatini DM Taipale J Perrimon N Bernards R 《Nature methods》2006,3(10):777-779
Large-scale RNA interference (RNAi)-based analyses, very much as other 'omic' approaches, have inherent rates of false positives and negatives. The variability in the standards of care applied to validate results from these studies, if left unchecked, could eventually begin to undermine the credibility of RNAi as a powerful functional approach. This Commentary is an invitation to an open discussion started among various users of RNAi to set forth accepted standards that would insure the quality and accuracy of information in the large datasets coming out of genome-scale screens. 相似文献
64.
During tail regeneration in urodele amphibians such as axolotls, all of the tissue types, including muscle, dermis, spinal cord, and cartilage, are regenerated. It is not known how this diversity of cell types is reformed with such precision. In particular, the number and variety of mature cell types in the remaining stump that contribute to the blastema is unclear. Using Nomarski imaging, we followed the process of regeneration in the larval axolotl tail. Combining this with in vivo fluorescent labeling of single muscle fibers, we show that mature muscle dedifferentiates. Muscle dedifferentiation occurs by the synchronous fragmentation of the multinucleate muscle fiber into mononucleate cells followed by rapid cell proliferation and the extension of cell processes. We further show that direct clipping of the muscle fiber and severe tissue damage around the fiber are both required to initiate dedifferentiation. Our observations also make it possible to estimate for the first time how many of the blastema cells arise specifically from muscle dedifferentiation. Calculations based on our data suggest that up to 29% of nondermal-derived cells in the blastema come from dedifferentiation of mature muscle fibers. Overall, these results show that endogenous multinucleate muscle fibers can dedifferentiate into mononucleate cells and contribute significantly to the blastema. 相似文献
65.
Valentina C Sladky Katja Knapp Tamas G Szabo Vincent Z Braun Laura Bongiovanni Hilda van den Bos Diana CJ Spierings Bart Westendorp Ana Curinha Tatjana Stojakovic Hubert Scharnagl Gerald Timelthaler Kaoru Tsuchia Matthias Pinter Georg Semmler Floris Foijer Alain de Bruin Thomas Reiberger Nataliya RohrUdilova Andreas Villunger 《EMBO reports》2020,21(12)
Polyploidization frequently precedes tumorigenesis but also occurs during normal development in several tissues. Hepatocyte ploidy is controlled by the PIDDosome during development and regeneration. This multi‐protein complex is activated by supernumerary centrosomes to induce p53 and restrict proliferation of polyploid cells, otherwise prone for chromosomal instability. PIDDosome deficiency in the liver results in drastically increased polyploidy. To investigate PIDDosome‐induced p53‐activation in the pathogenesis of liver cancer, we chemically induced hepatocellular carcinoma (HCC) in mice. Strikingly, PIDDosome deficiency reduced tumor number and burden, despite the inability to activate p53 in polyploid cells. Liver tumors arise primarily from cells with low ploidy, indicating an intrinsic pro‐tumorigenic effect of PIDDosome‐mediated ploidy restriction. These data suggest that hyperpolyploidization caused by PIDDosome deficiency protects from HCC. Moreover, high tumor cell density, as a surrogate marker of low ploidy, predicts poor survival of HCC patients receiving liver transplantation. Together, we show that the PIDDosome is a potential therapeutic target to manipulate hepatocyte polyploidization for HCC prevention and that tumor cell density may serve as a novel prognostic marker for recurrence‐free survival in HCC patients. 相似文献
66.
This paper provides evidence for the identification of the language of the uncontacted indigenous group called Carabayo, who live in voluntary isolation in the Colombian Amazon region. The only linguistic data available from this group is a set of about 50 words, most of them without reliable translations, that were collected in 1969 during a brief encounter with one Carabayo family. We compare this material with various languages (once) spoken in the region, showing that four attested Carabayo forms (a first person singular prefix and words for ‘warm’, ‘father’, and ‘boy’) display striking similarities with Yurí and at least 13 Carabayo forms display clear correspondences with contemporary Tikuna. Tikuna and Yurí are the only two known members of the Tikuna-Yurí linguistic family. Yurí was documented in the 19th century but has been thought to have become extinct since. We conclude that the Carabayo – directly or indirectly – descend from the Yurí people whose language and customs were described by explorers in the 19th century, before they took up voluntary isolation, escaping atrocities during the rubber boom in the early 20th century. 相似文献
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Anni 2.0 is an online tool () to aid the biomedical researcher with a broad range of information needs. Anni provides an ontology-based interface to MEDLINE
and retrieves documents and associations for several classes of biomedical concepts, including genes, drugs and diseases,
with established text-mining technology. In this article we illustrate Anni's usability by applying the tool to two use cases:
interpretation of a set of differentially expressed genes, and literature-based knowledge discovery. 相似文献
70.
M Lundervold EJ Milner-Gulland CJ O'Callaghan C Hamblin A Corteyn AP Macmillan 《Acta veterinaria Scandinavica》2004,45(4):211-224
The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from
958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic
haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence
in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although
we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The
seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not
having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are
also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village
level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which
vary at the raion (county) level. 相似文献