20 research outputs found
Ac-induced disruption of the doubleDs structure in tomato
The maize doubleDs element is stably maintained in the tomato genome. Upon the subsequent introduction of Ac into a plant containing doubleDs, disruption of the doubleDs structure and DNA rearrangements at the site of the doubleDs element were observed. No indications were obtained for excision of the complete doubleDs structure. The consequences of transactivation of doubleDs in these experiments are different from those described for transactivation of single Ds elements in tomato. The mechanisms by which such rearrangements could have occurred in tomato are discussed in relation to complex insertions containing doubleDs in maize
Characterization of the Ac/Ds behaviour in transgenic tomato plants using plasmid rescue
We describe the use of plasmid rescue to facilitate studies on the behaviour of Ds and Ac elements in transgenic tomato plants. The rescue of Ds elements relies on the presence of a plasmid origin of replication and a marker gene selective in Escherichia coli within the element. The position within the genome of modified Ds elements, rescued both before and after transposition, is assigned to the RFLP map of tomato. Alternatively to the rescue of Ds elements equipped with plasmid sequences, Ac elements are rescued by virtue of plasmid sequences flanking the element. In this way, the consequences of the presence of an (active) Ac element on the DNA structure at the original site can be studied in detail. Analysis of a library of Ac elements, rescued from the genome of a primary transformant, shows that Ac elements are, infrequently, involved in the formation of deletions. In one case the deletion refers to a 174 bp genomic DNA sequence immediately flanking Ac. In another case, a 1878 bp internal Ac sequence is deleted
A comparative study of Tam3 and Ac transposition in transgenic tobacco and petunia plants
Transposition of the Anthirrinum majus Tam3 element and the Zea mays Ac element has been monitored in petunia and tobacco plants. Plant vectors were constructed with the transposable elements cloned into the leader sequence of a marker gene. Agrobacterium tumefaciens-mediated leaf disc transformation was used to introduce the transposable element constructs into plant cells. In transgenic plants, excision of the transposable element restores gene expression and results in a clearly distinguishable phenotype. Based on restored expression of the hygromycin phosphotransferase II (HPTII) gene, we established that Tam3 excises in 30% of the transformed petunia plants and in 60% of the transformed tobacco plants. Ac excises from the HPTII gene with comparable frequencies (30%) in both plant species. When the β-glucuronidase (GUS) gene was used to detect transposition of Tam3, a significantly lower excision frequency (13%) was found in both plant species. It could be shown that deletion of parts of the transposable elements Tam3 and Ac, removing either one of the terminal inverted repeats (TIR) or part of the presumptive transposase coding region, abolished the excision from the marker genes. This demonstrates that excision of the transposable element Tam3 in heterologous plant species, as documented for the autonomous element Ac, also depends on both properties. Southern blot hybridization shows the expected excision pattern and the reintegration of Tam3 and Ac elements into the genome of tobacco plants.
Intramural esophageal cyst: the role of endoscopic ultrasonography.
We report a case of symptomatic congenital esophageal cyst. The diagnostic approach and the role of endoscopic ultrasonography in the preoperative diagnosis, especially when computed tomography demonstrates a high attenuation mass, are emphasized.Case ReportsJournal Articleinfo:eu-repo/semantics/publishe
Intraventricular rhabdoid tumor: first case report in a young adult
info:eu-repo/semantics/nonPublishe
Percutaneous treatment of iatrogenic iliocaval fistula related to endograft placement for abdominal aortic aneurysm
The authors report a case of iatrogenic dissection occurring during endovascular treatment of an abdominal aortic aneurysm. The dissection was related to catheterization maneuvers that led to the development of a symptomatic arteriovenous fistula, which was successfully closed by coil embolization.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Supported PCR: an efficient procedure to amplify sequences flanking a known DNA segment
We describe a novel modification of the polymerase chain reaction for efficient in vitro amplification of genomic DNA sequences flanking short stretches of known sequence. The technique utilizes a target enrichment step, based on the selective isolation of biotinylated fragments from the bulk of genomic DNA on streptavidin-containing support. Subsequently, following ligation with a second universal linker primer, the selected fragments can be amplified to amounts suitable for further molecular studies. The procedure has been applied to recover T-DNA flanking sequences in transgenic tomato plants which could subsequently be used to assign the positions of T-DNA to the molecular map of tomato. The method called supported PCR (sPCR) is a simple and efficient alternative to techniques used in the isolation of specific sequences flanking a known DNA segment
The use of transgenic plants to understand transposition mechanisms and to develop transposon tagging strategies
This review compares the activity of the plant transposable elements Ac, Tam3, En/Spm and Mu in heterologous plant species and in their original host. Mutational analysis of the autonomous transposable elements and two-element systems have supplied data that revealed some fundamental properties of the transposition mechanism. Functional parts of Ac and En/Spm were detected by in vitro binding studies of purified transposase protein and have been tested for their importance in the function of these transposable elements in heterologous plant species. Experiments that have been carried out to regulate the activity of the Ac transposable element are in progress and preliminary results have been compiled. Perspectives for manipulated transposable elements in transposon tagging strategies within heterologous plant species are discussed.
Giant colonic diverticulum: Presentation of one case and review of the literature
Since the first case described in 1946, fewer than 100 cases of giant colonic diverticula have been reported in the literature. We discuss the clinical, radiologic, and pathologic findings in a case of giant colonic diverticulum and review the etiology and differential diagnosis.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Gastric Embolization as Treatment for Overweight Patients; Efficacy and Safety.
OBJECTIVES: The aim of this study was to evaluate the efficacy and safety of left gastric artery (LGA) embolization for the treatment of overweight patients who weren't candidates for bariatric surgery. MATERIALS AND METHODS: We retrospectively collected data of 16 patients who underwent a selective embolization of the LGA. The mean body mass index (BMI) before intervention was 28.9 kg/m2 ± 2.5, and therefore, patients were not candidates for bariatric surgery in Belgium. The embolization was realized with 500-700 µm particles via the right common femoral artery approach. Before and following the intervention, an upper endoscopy was performed. Patient demographics, weight loss, hunger sensation and a satisfactory scale were reviewed. RESULTS: Between February 2015 and May 2017, 16 overweight patients were treated, one embolization was unsuccessful. Four (25%) patients were lost in follow-up. Nine (56%) patients showed early weight loss, one (6%) maintained his bodyweight and one (6%) patient underwent bariatric surgery 2 years after consultation. Only one (6%) patient had a gastric ulceration on control endoscopy. One (6%) patient ended in the intensive care unit for pancreatitis and gastric perforation. The mean weight loss was 8 kg ± 5.12, reducing their mean BMI to 25.5 ± 3.5. The hunger sensation was decreased, and patients were satisfied. CONCLUSION: This is a preliminary study in an overweight population that appears to induce weight loss and appetite suppression. Larger studies are needed to confirm these preliminary findings