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1.
The isolation of two multi-resistance transposons, Tn2425 and Tn1831, and their relation to Tn21 and Tn2424, is described. A 1.7 kb segment present in Tn2424 and Tn2425 was identified as an IS element by rec-independent transposition, resulting in a cointegrate structure that carries two direct repeated copies of the IS element. By the isolation of this IS element we demonstrated that transposition is one mechanism leading to sequence variations in Tn21-like structures, especially in the region between the mer operon and the sul gene. 相似文献
2.
A transposable element, Tn2401, was found in a clinical isolate of Pseudomonas aeruginosa. Tn2401 had a size of 7190 nucleotides and encoded aminoglycoside 3'-phosphotransferase and aminoglycoside 6'-N-acetyltransferase. The sequence encoding the former enzyme was homologous with that of Tn903. Pseudomonas aeruginosa strains harbouring this transposon were resistant to kanamycin, neomycin, lividomycin, ribostamycin, paromomycin, netilmycin, tobramycin, dibekacin, gentamicin, sisomicin, and butirosin. 相似文献
3.
Anne-Sophie Yribarren Daniel Thomas Alain Friboulet Bérangère Avalle 《European journal of biochemistry》2003,270(13):2789-2795
A library of random peptide sequences was used to select peptides that inhibit an anti-idiotypic catalytic Ig, immunoglobulin (IgG) 9G4H9, with a beta-lactamase-like activity. This library displays cyclic heptapeptides on the surface of bacteriophages and represents a collection of up to 4.5 x 109 peptides. The first selection step aimed at enriching the library in species that bind to the whole Ig molecule. The second step was to discriminate peptides that bind to part of the molecule other than the active site. Selected peptides were then screened by surface plasmon resonance analysis. Those displaying measurable Kd values were assayed for their ability to inhibit the catalytic Ig. 相似文献
4.
Katarina Jansson Gunnar Kratz Anders Haegerstrand 《In vitro cellular & developmental biology. Animal》1996,32(9):534-540
Summary Reepithelialization of artificial partial thickness wounds made in biopsies of human skin was determined after 3, 5, or 7
d of incubation, submerged or elevated to the air-liquid interface. The biopsies were reepithelialized within 5–7 d, with
a more complete epidermal healing in wounds exposed to air. Both types of wounds showed similar time-course in deposition
of basement membrane components, as detected by immunofluorescence labeling. Laminin and collagen type VII were deposited
underneath the migrating tips, whereas collagen type IV was detected after reepithelialization. Markers of terminal differentiation
showed a pattern close to normal in the air-liquid incubated wounds after reepithelialization. Involucrin was detected in
the suprabasal regions of the migrating epidermis and thereafter in the upper half of neo-epidermis in the air-liquid incubated
wound. Filaggrin could not be detected in the submerged wounds at any time during healing, whereas wounds exposed to air showed
a well-differentiated epidermis by Day 7. Tritiated thymidine-incorporation indicated proliferation of epidermal and dermal
cells during reepithelialization and a maintained viability, as shown by cultivation of endothelial- and fibroblast-like cells
obtained from the dermis 7 d after wounding.
Reepithelialization in this humanin vitro model is supported by a matrix close to normal with the possibility of extracellular influences and cell-cell interactions
and, in addition, the technique is simple and reproducible. Therefore, we suggest this model for studies of regeneration in
culture and as a complement toin vivo studies on epidermal healing. 相似文献
5.
John J. Malinowski Bruce L. Grasberger Gary Trakshel Edward E. Huston Tracey M. Banks Patricia G. Brake Richard B. Ciccarelli Barry N. Jones James A. Koehn Diane Kratz Nicole Lundberg Panayiotis E. Stevis Carla T. Helaszek Mark A. Ator Angela M. Small Wood Travis Stams Byron Rubin Richard S. Alexander 《Protein science : a publication of the Protein Society》1995,4(10):2149-2155
6.
In an automobile accident, a young man sustained blunt trauma to the chest that caused injury to the fibrous skeleton of the heart. The mitral and tricuspid valves and their annuli were lacerated, the aortic annulus was separated from the ventricular septum, and the ventricular septum was disrupted; however, with surgical management, the patient survived. 相似文献
7.
8.
Beno?te Méry Jean-Baptiste Guy Sophie Espenel Anne-Sophie Wozny Stéphanie Simonet Alexis Vallard Gersende Alphonse Dominique Ardail Claire Rodriguez-Lafrasse Nicolas Magné 《World journal of stem cells》2016,8(1):13-21
Head and neck squamous cell cancer(HNSCC) is the sixth most common cancer in the world. Effective therapeutic modalities such as surgery, radiation, chemotherapy and combinations of each are used in the management of the disease. In most cases, treatment fails to obtain total cancer cure. In recent years, it appears that one of the key determinants of treatment failure may be the presence of cancer stem cells(CSCs) that escape currently available therapies. CSCs form a small portion of the total tumor burden but may play a disproportionately important role in determining outcomes. CSCs have stem features such as self-renewal, high migration capacity, drug resistance, high proliferation abilities. A large body of evidence points to the fact that CSCs are particularly resistant to radiotherapy and chemotherapy. In HNSCC, CSCs have been increasingly shown to have an integral role in tumor initiation, disease progression, metastasis and treatment resistance. In the light of such observations, the present review summarizes biological characteristics of CSCs in HNSCC, outlines targeted strategies for the successful eradication of CSCs in HNSCC including targeting the self-renewal controlling pathways, blocking epithelial mesenchymal transition, niche targeting, immunotherapy approaches and highlights the need to better understand CSCs biology for new treatments modalities. 相似文献
9.
10.
Anne-Sophie Fiorucci Olivier Michaud Emanuel Schmid-Siegert Martine Trevisan Laure Allenbach Petrolati Yetkin aka Ince Christian Fankhauser 《PLoS genetics》2022,18(5)
Shaded plants challenged with herbivores or pathogens prioritize growth over defense. However, most experiments have focused on the effect of shading light cues on defense responses. To investigate the potential interaction between shade-avoidance and wounding-induced Jasmonate (JA)-mediated signaling on leaf growth and movement, we used repetitive mechanical wounding of leaf blades to mimic herbivore attacks. Phenotyping experiments with combined treatments on Arabidopsis thaliana rosettes revealed that shade strongly inhibits the wound effect on leaf elevation. By contrast, petiole length is reduced by wounding both in the sun and in the shade. Thus, the relationship between the shade and wounding/JA pathways varies depending on the physiological response, implying that leaf growth and movement can be uncoupled. Using RNA-sequencing, we identified genes with expression patterns matching the hyponastic response (opposite regulation by both stimuli, interaction between treatments with shade dominating the wound signal). Among them were genes from the PKS (Phytochrome Kinase Substrate) family, which was previously studied for its role in phototropism and leaf positioning. Interestingly, we observed reduced shade suppression of the wounding effect in pks2pks4 double mutants while a PKS4 overexpressing line showed constitutively elevated leaves and was less sensitive to wounding. Our results indicate a trait-specific interrelationship between shade and wounding cues on Arabidopsis leaf growth and positioning. Moreover, we identify PKS genes as integrators of external cues in the control of leaf hyponasty further emphasizing the role of these genes in aerial organ positioning. 相似文献