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1.
Agrobacteria mediated Coleus blumei tumour tissues were cultured in vitro on MS medium. Sixteen diversified transformed callus cultures were maintained for several years in the absence of plant growth regulators and antibiotics without affecting the growth rate. Rosmarinic acid was detected spectrophotometrically in all tissue lines but in different quantities. The highest rosmarinic acid accumulation detected was 11% of dry tissue mass. The relation between culture growth and rosmarinic acid production was investigated in three callus lines. The lines showed different rosmarinic acid accumulation in relation to their growth rate; it was either parallel or inversely related to the tissue growth. The effects of certain medium constituents on the callus growth and rosmarinic acid accumulation were examined in four tumour cell lines. Addition of 4% or 5% sucrose stimulated rosmarinic acid synthesis and decreased callus growth. Nitrogen reduction to one half or one quarter of initial concentration did not affect rosmarinic acid synthesis and decreased callus growth in three lines, while it increased rosmarinic acid accumulation and callus growth in one line. Addition of 0.1 mg/l Phe stimulated rosmarinic acid production in two lines but had little effect on the rosmarinic acid level in others. Rosmarinic acid production was significantly improved on modified macronutrients, where the Ac2 line produced 16.5 mg of rosmarinic acid per tube (0.2 g of dry wt) after being in culture for 35 days.  相似文献   
2.
Three pumpkin embryogenic lines were initiated on wounded zygotic embryos cultured on medium with or without 2,4-dichlorophenoxyacetic acid (2,4-D). Somatic embryo development was controlled by the availability of various compounds in the medium: presence/absence of 2,4-D, nitrogen sources. The highest rate of DNA methylation was in the early embryo stages, predominantly on MSC medium with 2,4-D and on auxin-free medium supplemented with 1.0 mM NH4Cl. DNA methylation was correlated with early embryo development in a manner that was not exclusively dependent on the presence/absence of exogenous auxin. DNA methylation decreased during embryo maturation on auxin-free MSC medium and on auxin-free MSC supplemented with 12.3 M 5-azacytidine (5-azaC). The embryogenic features of the pumpkin tissue were preserved, even after a 2-month treatment with 5-azaC.Abbreviations 5-azaC 5-Azacytidine - CRED-RA Coupled restriction enzyme digestion and random amplification - 2,4-D 2,4-Dichlorophenoxyacetic acid - DNMRT Duncans new multiple range test - IAA Indole-3-acetic acid - 5-mC 5-Methylcytosine  相似文献   
3.
Embryogenic callus derived from pumpkin hypocotyl segments was induced and maintained for 15 years on MS medium supplemented with the auxins IBA (4.9 M), 2, 4-D (4.5 M) or IAA (5.7 M). On induction media continued embryo maturation and development of adult plants typically failed. Therefore, small embryogenic clumps and individually isolated embryos were subcultured two to four times on one of the conversion media: MS supplemented with 1.5% sucrose and (a) no hormone, (b) 2.9 M IAA, (c) 5.7 M IAA, (d) 11.4 M IAA, (e) 12 M IEt, (f) 3.8 M ABA or (g) 2% activated charcoal. The cell line and the kind of auxin used in the induction and maintenance medium, both had a marked influence on the development of plantlets. The best result was achieved with a line that has been induced and maintained for 15 years on MS with IBA. In the IBA line, out of 100 embryos, 77 developed into plantlets on MS medium supplemented with 11.4 M IAA.Abbreviations IAA indole-3-acetic acid - IBA indole-3-butyric acid - BA 6-benzylaminopurine - ABA abscisic acid - 2, 4-D 2, 4-di-chlorophenoxyacetic acid - IEt indole-3-etha-nol - MS Murashige and Skoog (1962) medium  相似文献   
4.
Callus tissue was induced on barley mesocotyl explants of germinated seven-day-old seedlings on MS medium supplemented with 2,4-D or 2,4,5-T in high concentrations. Two morphologically different tissue cultures were maintained in vitro for a long time: a callus tissue without organogenesis and a culture with high rhizogenic capacity. Shoots and plantlets were generated when the auxin-media induced callus was transferred to medium supplemented with 3 M TIBA. In 62% of cultures, during the first five subcultures, four to twentyeight plants per single mesocotyl were obtained. Some cultures produced shoots even in the 9th subculture, being in culture for nearly 14 months. The largest number of plants obtained per one mesocotyl was forty. Plantlets rooted well on MS with 5.7 M IAA and survived transplantation to soil in high percentages.Abbreviations IAA indole-3yl-acetic acid - BA 6-benzylaminopurine - 2,4-D 2,4-dichlorophenoxyacetic acid - 2,4,5-T 2,4,5-trichlorophenoxyacetic acid - TIBA 2,3,5-triiodobenzoic acid - MS Murashige and Skoog (1962) medium  相似文献   
5.

Background

The electronic nose (e-nose) detects volatile organic compounds (VOCs) in exhaled air. We hypothesized that the exhaled VOCs print is different in stable vs. exacerbated patients with chronic obstructive pulmonary disease (COPD), particularly if the latter is associated with airway bacterial infection, and that the e-nose can distinguish them.

Methods

Smell-prints of the bacteria most commonly involved in exacerbations of COPD (ECOPD) were identified in vitro. Subsequently, we tested our hypothesis in 93 patients with ECOPD, 19 of them with pneumonia, 50 with stable COPD and 30 healthy controls in a cross-sectional case-controlled study. Secondly, ECOPD patients were re-studied after 2 months if clinically stable. Exhaled air was collected within a Tedlar bag and processed by a Cynarose 320 e-nose. Breath-prints were analyzed by Linear Discriminant Analysis (LDA) with “One Out” technique and Sensor logic Relations (SLR). Sputum samples were collected for culture.

Results

ECOPD with evidence of infection were significantly distinguishable from non-infected ECOPD (p = 0.018), with better accuracy when ECOPD was associated to pneumonia. The same patients with ECOPD were significantly distinguishable from stable COPD during follow-up (p = 0.018), unless the patient was colonized. Additionally, breath-prints from COPD patients were significantly distinguished from healthy controls. Various bacteria species were identified in culture but the e-nose was unable to identify accurately the bacteria smell-print in infected patients.

Conclusion

E-nose can identify ECOPD, especially if associated with airway bacterial infection or pneumonia.  相似文献   
6.
Somatic embryogenesis in pumpkin can be induced on auxin-containing medium and also on hormone-free medium containing 1 mM ammonium (NH4+) as the sole source of nitrogen. Growth of NH4+-induced embryogenic tissue was slow and caused considerable acidification of the culture medium. Small spherical cells with dense cytoplasma formed proembryogenic cell clusters that could not develop into late stage embryos. Buffering of NH4+ medium with 25 mM 2-(N-morpholino)-ethane-sulfonic acid enhanced tissue proliferation, but no further differentiation was observed. Later stage embryos developed only after re-supply of nitrogen in form of nitrate or l-glutamine. Effects of nitrogen status and pH of culture media on ammonium assimilation were analyzed by following the activity of glutamine synthetase (GS) in relation to phenylalanine ammonia-lyase (PAL). Increased activity of GS and PAL in NH4+ induced tissue coincided with significantly higher activity of stress-related enzymes superoxide dismutase (SOD) and soluble peroxidase (POD), indicating oxidative stress response of embryogenic tissue to NH4+ as the sole source of nitrogen. In addition, considerable increase was observed in callose accumulation and esterase activity, the early markers of somatic embryogenesis. Activity of stress-related enzymes decreased after the re-supply of nitrate (20 mM) or Gln (10 mM) in combination with NH4+ (1 mM), which subsequently triggered globular embryo development. Together, these results suggest that stress responses, as affected by nitrogen supply, contribute to the regulation of embryogenic competence in pumpkin.  相似文献   
7.

Background  

Neuromyelitis optica (NMO) is an idiopathic, severe, inflammatory demyelinating disease of the central nervous system, that causes severe optic neuritis and myelitis attacks. Early discrimination between multiple sclerosis (MS) and NMO is important, as optimum treatment for both diseases may differ considerably.  相似文献   
8.
Summary Vicia faba callus line (VFS 1), isolated from expiants of immature embryo, grew satisfactorily onMurashige andSkoog complete medium with 1.38 M 2,4-D, or with 0.92 M 2,4-D to which 1.0 M kinetin was added. It also grew well on the B 5 modified medium containing 2.3 M 2,4-D and 25.0 M kinetin. On the last of these media the cultures grew more uniformly and without necrosis. They also showed diminishing variation in polyploidy in favour of diploids and corresponding aneuploids (hypodiploids).After being cultured for nearly three years on MS containing 1.38 M 2,4-D, 8–33% of cultures of VFS 1 were able to regenerate roots when transferred to either MS half strength with 5.37 M NAA, or to a medium without 2,4-D, or else to media with the addition of kinetin only (in various concentrations).  相似文献   
9.
Hypocotyl explants of pumpkin ( Cucurbita pepo L.) were inoculated aseptically on solid media containing Murashige and Skoog (MS) macro- and micronutrients, organic supplements, glucose as a carbon source, and indoleacetic acid (IAA) or one of its possible metabolic precursors, i.e. indole-3-ethanol [3-(2-hydroxyethyl)-indole, tryptophol], 2-(indol-3-yl)-ethyl α-L-arabinopyranoside (tryptophol arabinoside), and 2-(indol-3-yl)-ethyl β-D-glucopyranoside (tryptophol glucoside). Embryogenic callus and adventitious roots developed on the explants, the response depending on the source of auxin, its concentration, and endogenous, possibly genetic, factors. Hypocotyl sections did not form embryogenic tissues and did not survive on media which did not contain an auxin or auxin precursors. Fewer explants responded to IAA than to indole-3-ethanol. Its arabinopyranoside was even more effective, while only a few hypocotyl sections proliferated in the presence of the corresponding glucopyranoside. Embryogenic callus induced by any of the four above compounds could be subcultured on media containing the same source of auxin. Selected callus lines have been maintained for more than three years and have continued to form embryoids. Indole-3-ethanol and IAA were suitable for clonal propagation of regenerated plantlets by axillary and apical bud culture.  相似文献   
10.
Summary Wounding of explanted Pinus nigra primary explants followed by infection with Agrobacterium rhizogenes wild strains 8196, 15834, or with the pRiA4abc transconjugant strain of A. tumefaciens (C58 chromosomal background) resulted in adventitious root induction. Roots were formed in 60–97% of explants (1–3 roots/explant) but without a hairy root phenotype. The presence of T-DNA of pRi8196 or pRiA4abc in regenerated roots was confirmed by the opine (mannopinic acid) content. Transformation response was influenced by the bacterial strain, age of explant and period of co-cultivation. Both the aggregate state (liquid) of medium and the season of the year (spring) had a positive effect on the root induction and their development. Histological analysis of the transformed roots showed that complete elements of primary and secondary root structures were present but roots were always triarch or tetrarch in the central cylinder as opposed to the primary roots of the untransformed seedling wich are diarch.  相似文献   
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