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151.
Santos-Tierno Raphaela Garcia Renata Fonseca Eduardo Faleiro Fábio Moreira Davyson Pacheco Georgia Mansur Elisabeth 《Plant Cell, Tissue and Organ Culture》2021,146(3):635-641
Plant Cell, Tissue and Organ Culture (PCTOC) - Induction of somatic embryogenesis from in vitro-cultivated anthers represents a recent but poorly understood regeneration pathway for passion fruit... 相似文献
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Cell cycle regulation of the glyceraldehyde-3-phosphate dehydrogenase/uracil DNA glycosylase gene in normal human cells. 总被引:5,自引:1,他引:4 下载免费PDF全文
The cell cycle regulation of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH)/uracil DNA glycosylase (UDG) gene was examined in normal human cells. Steady state RNA levels were monitored by Northern blot analysis using a plasmid (pChug 20.1) which contained the 1.3 kb GAPDH/UDG cDNA. The biosynthesis of the 37 kDa GAPDH/UDG protein was determined using an anti-human placental GAPDH/UDG monoclonal antibody to immunoprecipitate the radiolabeled protein. Increases in steady state GAPDH/UDG mRNA levels were cell cycle specific. A biphasic pattern was observed resulting in a 19-fold increase in the amount of GAPDH/UDG mRNA. The biosynthesis of the 37 kDa GAPDH/UDG protein displayed a similar biphasic regulation with a 7-fold increase. Pulse-chase experiments revealed a remarkably short half life of less than 1 hr. for the newly synthesized 37 kDa protein, comparable to that previously documented for a number of oncogenes. GAPDH/UDG mRNA levels were markedly reduced at 24 hr. when DNA synthesis was maximal. These results define the GAPDH/UDG gene as cell cycle regulated with a characteristic temporal sequence of expression in relation to DNA synthesis. The cell cycle synthesis of a labile 37 kDa monomer suggests a possible regulatory function for this multidimensional protein. Further, modulation of the GAPDH/UDG gene in the cell cycle may preclude its use as a reporter gene when the proliferative state of the cell is not kept constant. 相似文献
154.
Chitosan flakes from shrimp shells and xerogels derived from branched 1-deoxyglycit-1-yl chitosan derivatives were examined by scanning electron microscopy; the former displayed relatively large, dome-shaped orifices and the latter were found to exhibit a wide variety of ultrastructures, ranging from smooth, nonporous to microporous and microfibrillar. Some correlation between the chemical structure of the side chains of the chitosan derivatives and their microarchitecture could be established. 相似文献
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Claudia Simões Norma Albarello Cátia Henriques Callado Tatiana Carvalho de Castro Elisabeth Mansur 《Plant Cell, Tissue and Organ Culture》2009,98(1):79-86
Alternative methods for in vitro shoot culture of Cleome rosea, a Brazilian herbaceous species with ornamental value and medicinal potential, were evaluated. A protocol for rapid in vitro
multiplication of roots, a valuable source of medicinal compounds, was also developed. Stem explants were cultured in liquid
media (continuous immersion and paper bridge), while root explants were cultivated in continuous immersion and on solidified
media. The highest numbers of shoots, 20 ± 4.6 shoots/explant, were obtained from stem explants incubated in a continuous
immersion system in a liquid medium supplemented with 2.2 μM BA. Root explants cultivated in liquid media produced only hyperhydrous
adventitious shoots. However, these explants generated 5.8 ± 0.8 shoots/explant by indirect organogenesis when cultivated
on solidified medium supplemented with 2.2 μM BA. In addition, root multiplication was achieved in liquid medium in the presence
of α-naphthaleneacetic acid. Adventitious shoots developed on newly formed roots when inoculated on solidified medium supplemented
with 2.2 μM BA. Shoot microcuttings developed roots when transferred onto solidified MS medium without growth regulators.
Rooted microcuttings were efficiently acclimatized when transferred ex vitro. 相似文献
159.
K. H. Nicolaides G. Azar D. Byrne C. Mansur K. Marks 《BMJ (Clinical research ed.)》1992,304(6831):867-869
OBJECTIVE--To examine the significance of fetal nuchal translucency at 10-14 weeks'' gestation in the prediction of abnormal fetal karyotype. DESIGN--Prospective screening study. SETTING--The Harris Birthright Research Centre for Fetal Medicine, King''s College Hospital, London. SUBJECTS--827 fetuses undergoing first trimester karyotyping by amniocentesis or chorionic villus sampling. MAIN OUTCOME MEASURE--Incidence of chromosomal defects. RESULTS--The incidence of chromosomal defects was 3% (28 of 827 cases). In the 51 (6%) fetuses with nuchal translucency 3-8 mm thick the incidence of chromosomal defects was 35% (18 cases). In contrast, only 10 of the remaining 776 (1%) fetuses were chromosomally abnormal. CONCLUSION--Fetal nuchal translucency > or = 3 mm is a useful first trimester marker for fetal chromosomal abnormalities. 相似文献
160.
V. L. M. De Pádua M. C. Pestana M. Margis-Pinheiro D. E. De Oliveira E. Mansur 《In vitro cellular & developmental biology. Plant》2000,36(5):374-378
Summary Direct gene transfer into peanut intact embryonic leaflets was performed through electroporation. In transient β-glucuronidase
expression assays, maximal expression was obtained by using pulses of 625 V cm−1 in EPRm (modified electroporation) buffer supplemented with 75 μM NaCl. Kanamycin-resistant plants were obtained, and the presence of the nptII gene was demonstrated by PCR analysis. The positive effect of electroporation on the efficiency of in vitro regeneration was demonstrated. Explants submitted to field strengths between 500 and 625 V cm−1 displayed a significantly increased number of shoots and originated faster growing calluses relative to control explants.
Whereas in control explants callus formation occurred only at the petiolule, electroporated leaflets developed additional
organogenic calluses on the foliar lamina.
These authors have contributed equally to this work. 相似文献