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Luiz Ricardo Hanai Eny Iochevet Segal Floh Maria Helena Pelegrinelli Fungaro Claudete Santa-Catarina Francine Matias de Paula Ana Maria Viana Maria Lucia Carneiro Vieira 《In vitro cellular & developmental biology. Plant》2010,46(4):368-377
Ocotea catharinensis is a rare tree species indigenous to the Atlantic rainforest of South America. In spite of its value as a hardwood species,
it is in danger of extinction. The species erratically produces seeds showing irregular flowering and slow growth. Therefore,
plants are not easily replaced. Tissue culture-based techniques are commonly used for obtaining living material for tree propagation
and in vitro preservation. Therefore, a high-frequency somatic embryogenic system was developed for the species. In the present work,
the genetic fidelity of cell aggregates and somatic embryos at various stages of in vitro development of O. catharinensis was investigated using RAPD and AFLP markers. Both analyses confirmed the absence of genetic variation in all developmental
stages of O. catharinensis embryogenic cultures, verifying that the in vitro system is genetically stable. The cultures were also analyzed for their methylation profiles at 5′-CCGG-3′ sites by identifying
methylation-sensitive amplification polymorphisms. Some of these markers differentiated cell aggregates from embryo bodies.
The sequencing of ten MSAP markers revealed that four sequences showed significant similarity to genes encoding plant proteins.
Particularly, the predicted amino acid sequence of the fragment designated as OcEaggHMttc155 was similar to the enzyme 1–aminocyclopropane-1-carboxylate oxidase (ACO), which is involved in the biosynthesis of ethylene,
and its expression was reported to occur from the beginning to the intermediate stages of plant embryo development. Here,
we suggest that this enzyme is possibly involved in the control of the earliest stages of somatic embryogenesis of O. catharinensis, and an approach to study ACO expression during somatic embryogenesis is proposed. 相似文献
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Nicole Winter Marcus Clauss Daryl Codron Jürgen Hummel Jaqueline Müller Henning Richter Patrick Kircher Jean-Michel Hatt Louise Franoise Martin 《Journal of morphology》2022,283(1):5-15
We determined location and amount of accumulated sand in the gastrointestinal tract (GIT) of rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus) fed diets containing external (silicate) abrasives. Computed tomographic abdominal images of rabbits (n = 44) and guinea pigs (n = 16) that each received varying numbers (4–7) of different diets for 14 days each (total n = 311 computed tomographs), and radiographs of dissected GIT and presence of silica in GIT content (n = 46 animals) were evaluated. In rabbits, the majority of accumulated sand was located in the caecal appendix, an elongated, intestinal structure in the left side of the abdomen. The ‘wash-back’ colonic separation mechanism in rabbits may be partly responsible for a retrograde transport of sand back to the caecum, where dense, small particles accumulate in the appendix. The appendix likely acted as a reservoir of these particles, leading to significant effects not only of the momentary but also of the previous diet on recorded sand volumes in the rabbits. Guinea pigs have no caecal appendix and a colonic separation mechanism not based on a ‘wash-back’. Less sand accumulation was found in their GIT without a specific location pattern, and there were less previous diet effects in this species. None of the rabbits or guinea pigs developed clinical signs of obstruction during the study, and the recorded sand volumes represented 1.0 ± 1.2% of the 14-d sand intake in rabbits and 0.2 ± 0.2% in guinea pigs. Accumulation of sand in volumes up to 10 cm3 in the GIT of rabbits does not seem to cause clinical health impairment. Large inter-individual differences in rabbits indicate inter-individual variation in proneness to sand accumulation. The reason for the presence of a sand-trapping caecal appendix in animals that are, due to their burrowing lifestyle and feeding close to the ground, predestined for accidental sand ingestion, remains to be unveiled. 相似文献
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dos Santos Jaqueline Pozzada Dittgen Caroline Lambrecht El Halal Shanise Lisie Mello Vanier Nathan Levien 《Food biophysics》2020,15(2):155-161
Food Biophysics - A versatile and effective method of producing polyvinyl alcohol (PVA)-xylanase (XY) fibers cross-linked by glutaraldehyde vapor (GA) is reported in the present study. Crosslinking... 相似文献
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Felipe de Azevedo Rosas Sergio Leonardo Favareto Garles Miller Matias Vieira Mariana Netto de Oliveira Felipe DAlmeida Costa Douglas Guedes de Castro 《Reports of Practical Oncology and Radiotherapy》2021,26(1):138
Primary MALT lymphoma arising at the dura is a rare circumstance with no categorical therapeutic plan in literature. There are few reports available with different treatment courses. Here, we report two cases with a long-term follow-up after the same pattern of management and review the literature. 相似文献
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