scholarly journals Protuberances are organized distinct regions of long-term callus: histological and transcriptomic analyses in kiwifruit

2021 ◽  
Vol 40 (4) ◽  
pp. 637-665 ◽  
Author(s):  
Małgorzata Czernicka ◽  
Iwona Chłosta ◽  
Kinga Kęska ◽  
Małgorzata Kozieradzka-Kiszkurno ◽  
Mohib Abdullah ◽  
...  
Keyword(s):  
Secondary Metabolite ◽  
De Novo ◽  
Starch Granules ◽  
Shoot Bud ◽  
Molecular Features ◽  
Regenerated Plants ◽  
Shoot Bud Regeneration ◽  
Morphological Sign ◽  
Beta Glucosidase

Abstract Key message Macroscopic, ultrastructural, and molecular features—like a ball shape, the presence of starch granules, and the up-regulation of genes involved in carbohydrate metabolism and secondary metabolite biosynthesis—distinguish PT regions within a callus. Abstract The modification of the mass of pluripotent cells into de novo shoot bud regeneration is highly relevant to developmental biology and for agriculture and biotechnology. This study deals with protuberances (PT), structures that appear during the organogenic long-term culturing of callus (OC) in kiwifruit. These ball-shaped regions of callus might be considered the first morphological sign of the subsequent shoot bud development. Sections of PT show the regular arrangement of some cells, especially on the surface, in contrast to the regions of OC beyond the PT. The cells of OC possess chloroplasts; however, starch granules were observed only in PTs’ plastids. Transcriptomic data revealed unique gene expression for each kind of sample: OC, PT, and PT with visible shoot buds (PT–SH). Higher expression of the gene involved in lipid (glycerol-3-phosphate acyltransferase 5 [GPAT5]), carbohydrate (granule-bound starch synthase 1 [GBSS1]), and secondary metabolite (beta-glucosidase 45 [BGL45]) pathways were detected in PT and could be proposed as the markers of these structures. The up-regulation of the regulatory associated protein of TOR (RAPTOR1) was found in PT–SH. The highest expression of the actinidain gene in leaves from two-year-old regenerated plants suggests that the synthesis of this protein takes place in fully developed organs. The findings indicate that PT and PT–SH are specific structures within OC but have more features in common with callus tissue than with organs.

scholarly journals Conservation and Production of Ipecac (Cephaelis ipecacuanha Rich.) Plants from Long Term Shoot Cultures

1970 ◽  
Vol 18 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Rituparna Kundu Chaudhuri ◽  
Timir Baran Jha
Keyword(s):  
Growth Conditions ◽  
Shoot Cultures ◽  
Shoot Bud ◽  
Regenerated Plants ◽  
One Year ◽  
Bud Initiation ◽  
Cephaelis Ipecacuanha ◽  
Important Medicinal Plant

In vitro germplasms of ipecac (Cephaelis ipecacuanha Rich.), an important medicinal plant, maintained through reduced growth conditions for more than 12-years, were used as source material for micropropagation. MS with different combinations of Kn (2 mg/l), BAP (2 mg/l), 2iP (2-3 mg/l), NAA (0.2 mg/l) and adenine (40-100 mg/l) as additive was used to induce fresh multiplication of shoots from the nodal meristems and direct shoot bud initiation on the internodal segments. Complete plant regeneration has been achieved from such long term cultures. Regenerated plants maintained their phenotypic and chromosomal stability. Eighty per cent hardened plants, survived in the field condition, are growing well and 25% of them produced flowers within one year. Long term preservation through reduced growth conditions and successful regeneration of morphologically stable plants with stable chromosome numbers (2n = 22) from such long term cultures of ipecae plants.  Key words: Long term culture, Ipecac, micropropagation, flowering D.O.I. 10.3329/ptcb.v18i2.3646 Plant Tissue Cult. & Biotech. 18(2): 157-164, 2008 (December)

scholarly journals Physiological responses of Xanthoria parietina to longterm copper excess: Role of the extracellular secondary metabolite parietin

2019 ◽  
Vol 43 (2) ◽  
pp. 133-142
Author(s):  
Ivana Biľová ◽  
Michal Goga ◽  
Martin Backor
Keyword(s):  
Secondary Metabolite ◽  
Chlorophyll A ◽  
De Novo ◽  
Physiological Parameters ◽  
Term Experiment ◽  
Xanthoria Parietina ◽  
Long Term Experiment ◽  
Lichen Thallus ◽  
Copper Excess

Xanthoria parietina is a common lichen that is widespread around the world. Tolerance of heavy metal pollution in this lichen is well known. Xanthoria parietina contains the secondary metabolite parietin, which protects the photobiont from high UV- radiation. Secondary metabolites of lichens have been found to form complexes with metal cations. In a long-term experiment (lasting 8 weeks), we tested the resistance of X. parietina with and without the secondary metabolite parietin against two concentrations of Cu (50 ?M and 500 ?M). Removal of parietin did not affect the measured physiological parameters. However, it caused higher accumulation of intracellular Cu. De novo synthesis of parietin in the lichen thallus after removal of the metabolite was not observed. Physiological parameters (chlorophyll a fluorescence, chlorophyll a integrity, content of soluble proteins, ergosterol levels, TBARS production) were affected by the higher dose of Cu during the long-term experiment. It seems that the secondary metabolite parietin does not protect the lichen against Cu excess.

scholarly journals Organogenesis and long-term micropropagatlon of Polish pea cultivars

2011 ◽  
Vol 72 (4) ◽  
pp. 295-302 ◽  
Author(s):  
Tomasz Pniewski ◽  
Joanna Wachowiak ◽  
Józef Kapusta ◽  
Andrzej B. Legocki
Keyword(s):  
De Novo ◽  
Ms Medium ◽  
Regeneration Capacity ◽  
Ex Vitro ◽  
Regenerated Plants ◽  
Axillary Meristems ◽  
Half Strength

The complete protocol for regeneration and long-term micropropagation of several Polish cultivars of pea (<em>Pisum sativum </em>L.) has been elaborated. The shoots were the most likely regenerated via de novo organogenesis. The adventitious buds formed in callus derived from cotyledons tissue adjacent to the axillary meristems of immature embryos. All cultivars' calli regenerated several shoots per explant on the MS medium supplemented with B5 vitamins and 4.5 mgl<sup>-1</sup> of BAP, however some differences in regeneration capacity among cultivars were observed. The plantlets were subsequently micropropagated with slightly higher efficiency and preserving a good viability over the long-term culture on a medium containing 2.0 mgl<sup>-1</sup> than one with 4.5 mgl<sup>-1</sup> of BAP. The additional step of the pre-conditioning culture of multiplicated shoots on a medium with very low BAP concentration i.e. 0.02 mgl<sup>-1</sup> was applied and appeared to be beneficial before rooting in vitro or grafting. The modified MS-derived medium with the half-strength of MS macroelements but with the full original dose of calcium and supplemented with B5 vitamins and 1.0 mgl<sup>-1</sup> of NAA was developed for effective rooting. The shoots were also sufficiently transferred into ex vitro conditions using grafting. The majority of the regenerated plants had adapted to in vivo conditions in a greenhouse and subsequently has set seeds. The presented protocol provides relatively efficient rate of de novo pea regeneration and would be useful for <em>Agrobacterium</em>-mediated transformation purposes.

Is 3 years adequate for tracking completely occluded coiled aneurysms?

2020 ◽  
Vol 133 (3) ◽  
pp. 758-764
Author(s):  
Eung Koo Yeon ◽  
Young Dae Cho ◽  
Dong Hyun Yoo ◽  
Su Hwan Lee ◽  
Hyun-Seung Kang ◽  
...  
Keyword(s):  
De Novo ◽  
Careful Monitoring ◽  
Surveillance Period ◽  
Radiological Data ◽  
De Novo Aneurysm ◽  
Low Probability ◽  
Almost All ◽  
Annual Risk

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.

Long-term in vitro Storage Technique of Valuable Birch Genotypes and Plant Production on its Basis

2019 ◽  
pp. 57-67
Author(s):  
T.M. Tabatskaya ◽  
N.I. Vnukova
Keyword(s):  
Plant Production ◽  
High Survival ◽  
Ex Vitro ◽  
Regenerative Capacity ◽  
In Vitro Storage ◽  
Interspecific Differences ◽  
Regenerated Plants ◽  
Growing Conditions

A technique for the long-term (up to 27 years) in vitro storage of valuable birch genotypes under normal (25 °C, 2.0 klx, 16-h day and 8-h night) and low temperature (4 °C, 0.5 klx, 6-h day and 18-h night) growing conditions on hormone-free media has been described. The study explored for the first time the influence of different strategies to store the clones of Betula pubescens and B. pendula var. сarelica (6 genotypes) on the regenerative capacity of collection samples, adaptive potential of regenerated plants and plant production by the in vitro and ex vitro techniques. It was established that both storage strategies provided a persistently high survival rate (82-100%) and regenerative capacity of in vitro shoots (the multiplication coefficient of 4.2-6.3 and rhizogenic activity of 90-100%). The clones retained their characteristics of height growth under the in vitro and ex vitro conditions, and demonstrated intraclonal homogeneity and lack of signs of somaclonal variability. The plants showed substantial interspecific differences at the stage of multiplication and transfer to the greenhouse. The highest percentage of acclimated plants (75-98% depending on the clone genotype) was obtained after planting of micro plants straight in the greenhouse, which simplified the technology and made plant production less costly. long-term in vitro storage, birch, species, genotype, micropropagation, ex vitro adaptation, plant material

scholarly journals Long-term outcomes of fully covered self-expandable metal stents versus plastic stents in chronic pancreatitis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sang Hoon Lee ◽  
Yeon Suk Kim ◽  
Eui Joo Kim ◽  
Hee Seung Lee ◽  
Jeong Youp Park ◽  
...  
Keyword(s):  
Chronic Pancreatitis ◽  
Clinical Efficacy ◽  
De Novo ◽  
Plastic Stents ◽  
Metal Stents ◽  
Plastic Stent ◽  
Sems Group ◽  
Spontaneous Migration

AbstractChronic pancreatitis (CP) related main pancreatic duct (MPD) stricture has been a challenge for endoscopists. Fully covered self-expandable metal stents (FC-SEMS) has been tried in CP patients, but the efficacy and safety are still controversial. Thus, we aim to compare the long-term clinical efficacy of FC-SEMS vs. plastic stent placement in persistent MPD strictures secondary to CP. Between 2007 and 2018, 80 chronic pancreatitis patients (58 males, median age 49 years), who underwent endoscopic placement of FC-SEMS (n = 26) and plastic stent (n = 54) for persistent MPD strictures after at least 3 months of initial single plastic stenting, were retrospectively analyzed during a median follow-up duration of 33.7 months. As a result, MPD stricture resolution rate was statistically higher in FC-SEMS group (87.0% vs. 42.0%, p < 0.001). Although immediate complications occurred similarly (38.5% vs. 37.0%, p = 0.902), spontaneous migration (26.9%) and de novo strictures (23.1%) were pronounced delayed complications in FC-SEMS group. Pain relief during follow-up was significantly higher in FC-SEMS group (76.9% vs. 53.7%, p = 0.046). The total procedure cost was similar in both groups ($1,455.6 vs. $1,596.9, p = 0.486). In comparison with plastic stent, FC-SEMS placement for persistent MPD strictures had favorable long-term clinical efficacy, with its typical complications like spontaneous migration and de novo strictures.

scholarly journals Clinical benefit of glasdegib plus low-dose cytarabine in patients with de novo and secondary acute myeloid leukemia: long-term analysis of a phase II randomized trial

2021 ◽  
Author(s):  
Michael Heuser ◽  
B. Douglas Smith ◽  
Walter Fiedler ◽  
Mikkael A. Sekeres ◽  
Pau Montesinos ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Phase Ii ◽  
Clinical Benefit ◽  
Myeloid Leukemia ◽  
Low Dose ◽  
De Novo ◽  
Secondary Acute Myeloid Leukemia ◽  
Low Dose Cytarabine ◽  
Acute Myeloid

AbstractThis analysis from the phase II BRIGHT AML 1003 trial reports the long-term efficacy and safety of glasdegib + low-dose cytarabine (LDAC) in patients with acute myeloid leukemia ineligible for intensive chemotherapy. The multicenter, open-label study randomized (2:1) patients to receive glasdegib + LDAC (de novo, n = 38; secondary acute myeloid leukemia, n = 40) or LDAC alone (de novo, n = 18; secondary acute myeloid leukemia, n = 20). At the time of analysis, 90% of patients had died, with the longest follow-up since randomization 36 months. The combination of glasdegib and LDAC conferred superior overall survival (OS) versus LDAC alone; hazard ratio (HR) 0.495; (95% confidence interval [CI] 0.325–0.752); p = 0.0004; median OS was 8.3 versus 4.3 months. Improvement in OS was consistent across cytogenetic risk groups. In a post-hoc subgroup analysis, a survival trend with glasdegib + LDAC was observed in patients with de novo acute myeloid leukemia (HR 0.720; 95% CI 0.395–1.312; p = 0.14; median OS 6.6 vs 4.3 months) and secondary acute myeloid leukemia (HR 0.287; 95% CI 0.151–0.548; p < 0.0001; median OS 9.1 vs 4.1 months). The incidence of adverse events in the glasdegib + LDAC arm decreased after 90 days’ therapy: 83.7% versus 98.7% during the first 90 days. Glasdegib + LDAC versus LDAC alone continued to demonstrate superior OS in patients with acute myeloid leukemia; the clinical benefit with glasdegib + LDAC was particularly prominent in patients with secondary acute myeloid leukemia. ClinicalTrials.gov identifier: NCT01546038.

scholarly journals Malpigmentation of Common Sole (Solea solea) during Metamorphosis Is Associated with Differential Synaptic-Related Gene Expression

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2273
Author(s):  
Menelaos Kavouras ◽  
Emmanouil E. Malandrakis ◽  
Ewout Blom ◽  
Kyriaki Tsilika ◽  
Theodoros Danis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nervous System ◽  
De Novo ◽  
Close Association ◽  
Ionic Channels ◽  
Long Term Potentiation ◽  
General Term ◽  
The Difference ◽  
Common Sole

In farmed flatfish, such as common sole, color disturbances are common. Dyschromia is a general term that includes the color defects on the blind and ocular sides of the fish. The purpose was to examine the difference in gene expression between normal pigmented and juveniles who present ambicoloration. The analysis was carried out with next-generation sequencing techniques and de novo assembly of the transcriptome. Transcripts that showed significant differences (FDR < 0.05) in the expression between the two groups, were related to those of zebrafish (Danio rerio), functionally identified, and classified into categories of the gene ontology. The results revealed that ambicolorated juveniles exhibit a divergent function, mainly of the central nervous system at the synaptic level, as well as the ionic channels. The close association of chromophore cells with the growth of nerve cells and the nervous system was recorded. The pathway, glutamate binding–activation of AMPA and NMDA receptors–long-term stimulation of postsynaptic potential–LTP (long term potentiation)–plasticity of synapses, appears to be affected. In addition, the development of synapses also seems to be affected by the interaction of the LGI (leucine-rich glioma inactivated) protein family with the ADAM (a disintegrin and metalloprotease) ones.

Long‐Term Follow‐Up of a Patient with a De Novo p. Arg769Cys Mutation in the ATP1A3 Gene

2021 ◽  
Author(s):  
Anjali Chouksey ◽  
Asish Vijayaraghavan ◽  
Sony Mohan ◽  
Srija Inturi ◽  
A.T. Prabhakar ◽  
...  
Keyword(s):  
De Novo ◽  
Long Term Follow Up ◽  
Atp1a3 Gene
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