• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.83-87
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• 2000

To investigate the effect of growth regulators and antioxidant in anther floating cultures of rice, anthers were cultured in liquid media supplemented with different growth regulators, and the effect of antioxidant mixture : (Sigma Chemical Co.) on callus induction and plant regeneration were investigated. N6 medium with 1 mg/L 2,4-D and 1 mg/L kinetin was the best for rice anther floating cultures, which showed 48.5% of callus induction and 6.8% of green plant regeneration. The callus induction was not affected by antioxidant mixture in liquid medium, and antioxidant mixture (250 mg/L) was effective for the reduction of brownish callus and improvement of plant regeneration Antioxidant mixture showed better effectiveness when it was supplemented to both media for callus induction and plant regeneration.

• Korean Journal of Plant Tissue Culture
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• v.22 no.4
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• pp.183-187
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• 1995

The relationship between the intracellular phosphate level and catharanthine production in hairy root cultures of Catharanthus roseus was investigated The growth of hairy root increased in proportion to the phosphate concentration in the growth medium. When hairy roots were cultured in a phosphate-free medium, the catharanthine content was increased to the highest level As the phosphate concentration in the medium was enhanced, the catharanthine content decreased proportionally. Hairy root cultures with elevated intracellular phosphate concentrations indicated that growth was proportional to the level of intracellular phosphate. Catharanthine production increased abruptly below an intracellular phosphate level of $100\;\mumoles/g$ dry wt. The intracellular phosphate level may play a key role in the regulation of growth and secondary metabolite production.

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.53-58
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• 1999

The gamma radiation-induced changes of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in callus cultures of cassava (Manihot esculenta Crantz) selected as a high yield of cell line for SOD were investigated. In normal cultures, the cell growth reached a maximum at 30 days after subculture (DAS), followed by a rapid decrease with further cultures. The SOD and POD specific activities (units/mg protein) showed the highest at the immediately after subculture and subsequently decreased to 20 DAS, and then increased to 30 DAS, whereas the CAT activity showed the lowest at just after subculture, and it continuously increased from 15 DAS to 30 DAS, showing a good correlation with the cell growth. Irradiation of gamma-ray of 50 and 70 Gy on 7 DAS inhibited significantly the cell growth by 50% and 80% at 14 days after treatment (DAT), respectively. In the cells irradiated with 70 Gy, SOD and POD specific activities increased by 4 and 2.5 folds at 14 DAT, respectively, whereas CAT activity was not affected. The results indicate that SOD and POD may be involved in the antioxidative mechanism in relation to oxidative stresses induced by subcultures and by gamma radiation in callus cultures of cassava.

• Korean Journal of Plant Tissue Culture
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• v.21 no.1
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• pp.47-53
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• 1994

The effects of light on the production of anthocyanin and betacyanin in cell suspension cultures of Vitis vinifera and Phytolacca americana were investigated. The cell growth of V.vinifera was little affected by exposure to light, but that of P.americana was markedly increased by light than in the dark In suspension cultures of V vinifera maximum accumulation of anthocyanin was observed during the stationary phase in continuous light By contrast, in suspension cultures of R americana, accumulation of betacyanin occured in parallel with cell division which showed two peaks after 4 days and 8 days of culture in continuous light whereas in continuous dark accumulation of anthocyanin and betacyanin did not occured However treatment of light interrupting for l, 12, and 24 h after 4 days in cell suspension. cultures of remarkably showed a slight anthocyanin accumulation, but after 8 days of culture remarkably accumulated by light interrupting for more than 12 h. In cultures of P. americana, the light treatment was more effective at 4th day than at 7th day after culture, but betacyanin accumulation was decreased again in the dark after light treatment These result indicate that the difference of light responses exist between the V.vinifera and the betacyanin of P. americana though cell suspension culture systems.

• Journal of Plant Biotechnology
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• v.2 no.2
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• pp.55-60
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• 2000

Experiments initiated 30 years ago to obtain selectable markers have led to a series of studies of Trp biosynthesis and anthranilate synthase (AS) the control enzyme using largely plant tissue cultures since they have experimental properties that can be readily exploited. Enzymological and compound feeding studies provided evidence that AS is the control point in the Trp biosynthesis branch and that altering the AS feedback control by the selection of mutants resistant to the Trp analog 5-methyl-tryptophan (5MT) can lead to the overproduction of this important amino acid. Plants regenerated from these Trp overproducing lines of most species also had high free Trp levels but Nicotiana tabaum (tobacco) plants expressed the feedback altered AS only in cultured cells and not in the regenerated plants. further tests by transient and stable expression of the cloned promoter for the naturally occurring tobacco feedback-insensitive AS, denoted ASA2, confirmed the tissue culture specific nature of the expression control. The 5MT caused by the expression of a feedback-insensitive AS from tobacco has been used to select protoplast fusion hybrids with several species since the resistance is expressed dominantly. Recently the ASA2 gene has been used successfully as a selectable marker to select transformed Astragalus sinicus and Glycine max hairy roots induced by Agrobactetium rhizogenes. These results show that the ASA2y-subunit can interact with the y-subunit of another species to form active feedback-insensitive enzyme that may be useful for selecting transformed cells. Plastid DNA transformation of tobacco has also effectively expressed ASA2 in the compartment in which Trp biosynthesis is localized in the cell.

• Archives of Plastic Surgery
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• v.42 no.1
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• pp.59-67
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• 2015

Background Negative-pressure wound therapy (NPWT) induces angiogenesis and collagen synthesis to promote tissue healing. Although acetic acid soaks normalize alkali wound conditions to raise tissue oxygen saturation and deconstruct the biofilms of chronic wounds, frequent dressing changes are required. Methods Combined use of NPWT and acetic acid irrigation was assessed in the treatment of chronic wounds, instilling acetic acid solution (1%) beneath polyurethane membranes twice daily for three weeks under continuous pressure (125 mm Hg). Clinical photographs, pH levels, cultures, and debrided fragments of wounds were obtained pre- and posttreatment. Tissue immunostaining (CD31, Ki-67, and CD45) and reverse transcription-polymerase chain reaction (vascular endothelial growth factor [VEGF], vascular endothelial growth factor receptor [VEGFR]; procollagen; hypoxia-inducible factor 1 alpha [HIF-1-alpha]; matrix metalloproteinase [MMP]-1,-3,-9; and tissue inhibitor of metalloproteinase [TIMP]) were also performed. Results Wound sizes tended to diminish with the combined therapy, accompanied by drops in wound pH (weakly acidic or neutral) and less evidence of infection. CD31 and Ki-67 immunostaining increased (P<0.05) post-treatment, as did the levels of VEGFR, procollagen, and MMP-1 (P<0.05), whereas the VEGF, HIF-1-alpha, and MMP-9/TIMP levels declined (P<0.05). Conclusions By combining acetic acid irrigation with negative-pressure dressings, both the pH and the size of chronic wounds can be reduced and infections be controlled. This approach may enhance angiogenesis and collagen synthesis in wounds, restoring the extracellular matrix.

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.351-355
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• 1997

Adventitious shoots were induced from cambial tissue cultures of 3-year-old seedlings using BLG mineral salts medium supplemented with 10 mM glutamine and 30 mM sucrose. The optimum growth regulator level for bud induction was 4,5 $\mu$M BA which produced average 25.5 shoots per cambium segment. Induced buds were elongated on GD medium supplemented with 30 mM sucrose followed by LMG medium supplemented with 30 mM sucrose for further shoot elongation. Elongated shoots were rooted on half-strength GD medium containing $0.54 ;\mu\textrm{M}$ NAA with the frequency of 20%. This system proved the high morphogenic potential of cambial tissue in larch.

• Animal cells and systems
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• v.16 no.4
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• pp.295-301
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• 2012

Interdigital tissue regression is one of the most well-known examples of embryonic programmed cell death, providing the mechanism behind separation of developing digits. Caspases have been shown to play a key part in this process, with activated caspase-3 localized between the developing digits. In caspase-3 knock-out adult mice, however, the digits are completely separated with no webbing. In other mutants with defects in the apoptotic machinery, such as Apaf1 deficient mice, interdigital tissue regression is initially inhibited but the webbing eventually disappears as alternative/additional cell death mechanisms step in. In order to investigate whether a similar temporal effect occurs after loss of caspase-3, we have used an in vitro approach to inhibit caspase-3 at specific times during digit separation. Previous limb explant culture approaches have encountered problems with proper limb development in culture, and thus a modified technique was used. The new approach enables detailed observation of the effects of caspase-3 inhibition on interdigital regression. Using these methods, we show that caspase-3 inhibition caused a delay in the loss of interdigital tissue compared with control explants, similar to that observed in Apaf1 mutant mice. Along with immunohistochemistry, active caspase-3 positive cells of the interdigital vs. digital regions were measured by flow cytometry. Notably, activated caspase-3 in vivo was found not only in the interdigital mesenchyme but also in the TUNEL negative digit region, supporting a role for caspase-3 in nonapoptotic events.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.97-101
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• 1967

Up to the present time, there are only three methods by which we can obtain bacteria free crown gall tissue. According to some papers related to this field, the first method is based on the works of Braun(53') who maintained infected plants at 46-47'c for several days. But the method has a problem that very few plants can tolerate this temperature. The second method is based on the well known observation that old tumors appear to be bacteria free at least 1 or 2% of the explants. Also this method is known to us as laborious and time consuming. The third method is the one we were using that was attempting to kill the bacteria with bacteriacidal agent such as Antibiotics. In fact., it is reported that almost complete control of crown gall of tomato was obtained by Blanchard('51) when plants were grown in a nutrient containing Aureomycin(20${\mu}g$/ml) following needle puncture with the gall bacteria. We have been engaged in making the experiment by applying solution of Penicillin, Streptomycin and of Chloramphenicol(Succinate free) to find the strong bacteriacidal agent through the method of disc plate, and to confirm the effect of antimicrobial action through the method of plant tissue culture system without possible injury to the host plant. The result of this report is the fact the strongest bacteriacidal agent among the above three Antibiotics was Chloramphenicol(Succinate free 1000 p.p.m). and that there happened no injury to the tissue cultures in a White's 10X media containing 1000 p.p.m. of Chloramphenicol.

• Journal of Ecology and Environment
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• v.46 no.3
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• pp.218-242
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• 2022

Background: Promising specific growth regulators are employed in the tissue cultures of various bamboo species. Specific natural hardening mixtures support the acclimatization and adaptation of bamboo under protected cultivation. Results: The growth regulators like 2, 4-Dichlorophenoxyacetic acid (2, 4-D), Naphthaleneacetic Acid (NAA), Thidiazuron (TDZ), 6-Benzylaminopurine (BAP), Kinetin, Gelrite, Benzyl Adenine (BA), Indole Butyric Acid (IBA), Coumarin, Putrescine, Gibberellic acid (GA₃), Indole Acetic Acid (IAA) has been widely used for callus induction, root regeneration and imposing plant regeneration in various species of bamboo such as Bambusa spp. and Dendrocalamus spp. Different combinations of growth regulators and phytohormones have been used for regenerating some of the major bamboo species. Natural hardening materials such as cocopeat, vermicompost, perlite, cow dung, farmyard manure, compost, soil, garden soil, and humus soil have been recommended for the acclimatization and adaptation of bamboo species. Standard combinations of growth regulators and hardening mixtures have imposed tissue culture, acclimatization, and adaptation in major bamboo species. Conclusions: Bamboo contributes to soil fertility improvement and stabilization of the environment. Bamboo species are also involved in managing the biogeochemical cycle and have immense potential for carbon sequestration and human use. This paper aims to review the various growth regulators, natural mixtures, and defined media involved in regenerating major bamboo species through in vitro propagation. In addition, the ecological benefits of safeguarding the environment are also briefly discussed.