915 resultados para Interstitial telomeric sequence
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A novel and efficient regioselective synthesis of various arylated highly congested 7-aryl-5-methylsulfanylindan-4-carbonitriles (3a-(), methyl 7-aryl-5-methylsulfanylindan-4-carboxylates (lOa-e) and 7-aryl-5-methylsulfanylindan-4-carboxylic acids (lla-e) through base-catalyzed reaction of 6-aryl-4-methylsulfanyl-2-oxo-2H-pyran-3-carbonitriles (la-() and methyl 6-aryl-4-methylsulfanyl-2-oxo-2Hpyran-3-carboxylates (9a-e) by cyclopentanone (2) has been delineated. The synthetic potential of 2-pyranone was explored further to generate mo'iecular diversity using 6-aryl-4-secamino- 2-oxo-2H-pyran-3-carbonitriles (7a-h), 5,6-diaryl-4-methylsulfanyl-2-oxo2H-pyran-3-carbonitriles (Sa,b) and methyl 5,6-diaryl-4- methylsulfanyl-2-oxo-2H-pyran-3-carboxylates (12a,b) as precursors for the ring transformation by cyclopentanone to assess the effects of substituents on the course of the reaction to obtain highly congested indans, 6,7diaryl-5-methylsulfanylindan-4-carbonitriles (6a,b), 7-aryl-5-(piperidin-I-yl)indancarbonitriles (8a-h) and methyl 6,7-4- diaryl-5-methylsulfanylindan-4-carboxylate 13a,b).
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This paper presents different application scenarios for which the registration of sub-sequence reconstructions or multi-camera reconstructions is essential for successful camera motion estimation and 3D reconstruction from video. The registration is achieved by merging unconnected feature point tracks between the reconstructions. One application is drift removal for sequential camera motion estimation of long sequences. The state-of-the-art in drift removal is to apply a RANSAC approach to find unconnected feature point tracks. In this paper an alternative spectral algorithm for pairwise matching of unconnected feature point tracks is used. It is then shown that the algorithms can be combined and applied to novel scenarios where independent camera motion estimations must be registered into a common global coordinate system. In the first scenario multiple moving cameras, which capture the same scene simultaneously, are registered. A second new scenario occurs in situations where the tracking of feature points during sequential camera motion estimation fails completely, e.g., due to large occluding objects in the foreground, and the unconnected tracks of the independent reconstructions must be merged. In the third scenario image sequences of the same scene, which are captured under different illuminations, are registered. Several experiments with challenging real video sequences demonstrate that the presented techniques work in practice.
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Multilocus sequence analysis (MLSA) based on recN, rpoA and thdF genes was done on more than 30 species of the family Enterobacteriaceae with a focus on Cronobacter and the related genus Enterobacter. The sequences provide valuable data for phylogenetic, taxonomic and diagnostic purposes. Phylogenetic analysis showed that the genus Cronobacter forms a homogenous cluster related to recently described species of Enterobacter, but distant to other species of this genus. Combining sequence information on all three genes is highly representative for the species' %GC-content used as taxonomic marker. Sequence similarity of the three genes and even of recN alone can be used to extrapolate genetic similarities between species of Enterobacteriaceae. Finally, the rpoA gene sequence, which is the easiest one to determine, provides a powerful diagnostic tool to identify and differentiate species of this family. The comparative analysis gives important insights into the phylogeny and genetic relatedness of the family Enterobacteriaceae and will serve as a basis for further studies and clarifications on the taxonomy of this large and heterogeneous family.
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We report a high-quality draft sequence of the genome of the horse (Equus caballus). The genome is relatively repetitive but has little segmental duplication. Chromosomes appear to have undergone few historical rearrangements: 53% of equine chromosomes show conserved synteny to a single human chromosome. Equine chromosome 11 is shown to have an evolutionary new centromere devoid of centromeric satellite DNA, suggesting that centromeric function may arise before satellite repeat accumulation. Linkage disequilibrium, showing the influences of early domestication of large herds of female horses, is intermediate in length between dog and human, and there is long-range haplotype sharing among breeds.
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Since the mapping of the human genome and the technical innovations in the field of biotechnology, patent law has gone through great controversies. Protection is required for an investor to make an investment but how broad should the given protection be? Whether the invention is a mi- cro-organism capable of dissolving crude oil, or the gene of a soya plant, the genetic engineering required for their production entails vast amounts of capi- tal. The policy in that respect is tailored by legislative acts and judicial decisions, ensuring a fair balance be- tween the interests of patent right holders and third parties. However, the policy differs from jurisdiction to jurisdiction, thus creating inconsistencies with re- gards to the given protection to the same invention, and as a result this could deter innovation and pro- mote stagnation. The most active actors shaping the patent policy on an international level are the patent offices of the United States of America, Japan and the European Patent Organization. These three patent offices have set up a cooperation programme in order to promote and improve efficiency with regards to their patent policies on a global scale. However, recent judicial de- velopments have shown that the policy in respect to the field of biotechnology differs between the patent regimes of the United States of America and the two- layer system of the European Patent Organisation/ the European Union.
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We present an optimized multilocus sequence typing (MLST) scheme with universal primer sets for amplifying and sequencing the seven target genes of Campylobacter jejuni and Campylobacter coli. Typing was expanded by sequence determination of the genes flaA and flaB using optimized primer sets. This approach is compatible with the MLST and flaA schemes used in the PubMLST database and results in an additional typing method using the flaB gene sequence. An identification module based on the 16S rRNA and rpoB genes was included, as well as the genetic determination of macrolide and quinolone resistances based on mutations in the 23S rRNA and gyrA genes. Experimental procedures were simplified by multiplex PCR of the 13 target genes. This comprehensive approach was evaluated with C. jejuni and C. coli isolates collected in Switzerland. MLST of 329 strains resulted in 72 sequence types (STs) among the 186 C. jejuni strains and 39 STs for the 143 C. coli isolates. Fourteen (19%) of the C. jejuni and 20 (51%) of the C. coli STs had not been found previously. In total, 35% of the C. coli strains collected in Switzerland contained mutations conferring antibiotic resistance only to quinolone, 15% contained mutations conferring resistance only to macrolides, and 6% contained mutations conferring resistance to both classes of antibiotics. In C. jejuni, these values were 31% and 0% for quinolone and macrolide resistance, respectively. The rpoB sequence allowed phylogenetic differentiation between C. coli and C. jejuni, which was not possible by 16S rRNA gene analysis. An online Integrated Database Network System (SmartGene, Zug, Switzerland)-based platform for MLST data analysis specific to Campylobacter was implemented. This Web-based platform allowed automated allele and ST designation, as well as epidemiological analysis of data, thus streamlining and facilitating the analysis workflow. Data networking facilitates the exchange of information between collaborating centers. The described approach simplifies and improves the genotyping of Campylobacter, allowing cost- and time-efficient routine monitoring.
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A multilocus sequence typing (MLST) scheme was established and evaluated for Mycoplasma hyopneumoniae, the etiologic agent of enzootic pneumonia in swine with the aim of defining strains. Putative target genes were selected by genome sequence comparisons. Out of 12 housekeeping genes chosen and experimentally validated, the 7 genes efp, metG, pgiB, recA, adk, rpoB, and tpiA were finally used to establish the MLST scheme. Their usefulness was assessed individually and in combination using a set of well-defined field samples and strains of M. hyopneumoniae. A reduction to the three targets showing highest variation (adk, rpoB, and tpiA) was possible resulting in the same number of sequence types as using the seven targets. The established MLST approach was compared with the recently described typing method using the serine-rich repeat motif-encoding region of the p146 gene. There was coherence between the two methods, but MLST resulted in a slightly higher resolution. Farms recognized to be affected by enzootic pneumonia were always associated with a single M. hyopneumoniae clone, which in most cases differed from farm to farm. However, farms in close geographic or operational contact showed identical clones as defined by MLST typing. Population analysis showed that recombination in M. hyopneumoniae occurs and that strains are very diverse with only limited clonality observed. Elaborate classical MLST schemes using multiple targets for M. hyopneumoniae might therefore be of limited value. In contrast, MLST typing of M. hyopneumoniae using the three genes adk, rpoB, and tpiA seems to be sufficient for epidemiological investigations by direct amplification of target genes from lysate of clinical material without prior cultivation.
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Synthetic peptides containing a repetitive hexapeptide sequence (Ala-His-His-Ala-Ala-Asp) of malarial histidine-rich protein II were evaluated for binding with haem in vitro. The pattern of haem binding suggested that each repeat unit of this sequence provides one binding site for haem. Chloroquine inhibited the haem-peptide complex formation with preferential formation of a haem chloroquine complex. In vitro studies on haem polymerisation showed that none of the peptides could initiate haemozoin formation. However, they could inhibit haemozoin formation promoted by a malarial parasite extract, possibly by competitively binding free haem. These results indicate this hexapeptide sequence represents the haem binding site of the malarial histidine-rich protein and possibly the site of nucleation for haem polymerisation.
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We report a case of tularemia in a common marmoset (Callithrix jacchus) diagnosed by determination of the isolate's 16S ribosomal RNA (rRNA) gene sequence. Pathological examination of the animal revealed a multifocal acute necrotizing hepatitis, interstitial nephritis, splenitis, and lymphangitis of the mandibular, retropharyngeal, and cervical and mesenteric lymph nodes. Moreover, multiple foci of acute necrosis were found in the epithelium of the jejunum and the interstitium of the lung. Bacteriological investigations revealed a septicemia. The isolated infectious agent was uncommon, not routinely diagnosed in our laboratory and therefore difficult to identify by conventional tools in a reasonable time and effort. thus, we decided to perform a genetic analysis based on the 16S rRNA gene sequence. Thereby, an infection with Francisella tularensis, the causative agent of tularemia, was unambiguously diagnosed. This shows the great advantage 16S rRNA gene sequencing has as a general identification approach for unusual or rare isolates.
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PURPOSE To analyse the clinical outcome after salvage lumpectomy and multi-catheter brachytherapy (MCB) for ipsilateral breast tumour recurrence (IBTR). MATERIAL AND METHODS Between 09/00 and 09/10, 217 patients presenting an IBTR underwent lumpectomy and MCB (low, pulsed, or high-dose rate). Survival rates without second local recurrence (2nd LR), distant metastasis (DM), and overall survival (OS) were analysed as well as late effects and cosmetic results. Univariate and multivariate analyses (MVA) based on IBTR data were performed to find prognostic factors for 2nd LR, DM, and OS. RESULTS Median follow-up after the IBTR was 3.9 years [range: 1.1-10.3]. Five and 10-year actuarial 2nd LR rates were 5.6% [range: 1.5-9.5] and 7.2% [range: 2.1-12.1], respectively. Five and 10-year actuarial DM rates were 9.6% [range: 5.7-15.2] and 19.1% [range: 7.8-28.3], respectively. Five and 10-year actuarial OS rates were 88.7% [range: 83.1-94.8] and 76.4% [range: 66.9-87.3], respectively. In MVA, histological grade was prognostic factor for 2nd LR (p=0.008) and OS (p=0.02); while tumour size was prognostic factor for DM (p=0.03). G3-4 complication rate was 11%. Excellent/good cosmetic result was achieved in 85%. CONCLUSION This study suggests that in case of IBTR, lumpectomy plus MCB is feasible and effective in preventing 2nd LR with an OS rate at least equivalent to those achieved with salvage mastectomy.