scholarly journals Regeneration of bulblets on bulb scale segments of hyacinth in vitro.

1973 ◽  
Vol 21 (2) ◽  
pp. 129-138 ◽  
Author(s):  
R.L.M. Pierik ◽  
M.A. Ruibing

Hyacinth bulbs, cv. Pink Pearl, harvested in June were held at 25 deg C for 1-5 months, after which bulb scales were removed for tissue culture in modified basic medium. The length of the holding period had little effect on the number of bulblets that regenerated, but the average bulb weight increased as the holding period lengthened, attaining a maximum with bulbs held until 1-15 October. There were wide differences in regenerative ability and bulblet growth between bulbs of the same harvest and size. The number of bulblets that regenerated was not affected by scale age, but bulblet growth from the older scales (nos. 7-18) was much better than from the younger scales. Regeneration and growth of explants from the proximal parts of the scales was much better than from the distal parts, and 3-cm-long explants gave much better results than shorter ones. Inverting the explants in the culture medium was favourable to regeneration and growth. In further studies on the effects of temperature and light, bulb regeneration was accelerated by raising the temperature, the optimum being 21.6 deg . The greatest number of bulblets/explant, however, was obtained at 13 deg , and the highest bulb weight at 21.6 or 24.8 deg . There were no differences in regeneration and bulblet growth between scales grown in continuous light or in darkness. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Blood ◽  
1974 ◽  
Vol 44 (1) ◽  
pp. 77-85 ◽  
Author(s):  
Allan J. Erslev

Abstract Normal rabbits exposed to 0.4 atmospheric pressure for 3 hr will generate about 40-60 U of erythropoietin during a subsequent 3-hr period. If the kidneys were removed from 3-hr hypoxic animals, washed carefully, and perfused for 3 hr by recirculation with a serum-tissue culture mixture, each kidney generated about 14 U of erythropoietin in vitro. Perfusion of normal kidneys did not result in the production of erythropoietin, and only small amounts were generated if the perfusate contained Puromycin. Three-hour hypoxic kidneys perfused for 3 hr with a serum-free tissue culture medium were found to generate about 8 U of erythropoietin per kidney and similar kidneys perfused with saline about 1 U. These results indicate that erythropoietin is synthesized by kidney tissue and not produced by enzymatic activation of a plasma substrate.


1958 ◽  
Vol 36 (1) ◽  
pp. 171-184 ◽  
Author(s):  
Arthur E. Pasieka ◽  
Helen J. Morton ◽  
Joseph F. Morgan

Freshly-explanted chick embryonic kidney, chick embryonic liver, and trypsinized monkey kidney cortex cells have been cultivated in vitro in completely synthetic medium M 150. The amino acid changes in the nutrient medium during cultivation of these tissues have been studied by paper chromatography. A characteristic pattern of amino acid uptake and accumulation in the used culture medium has been demonstrated with each type of tissue culture. It has also been shown that, while the amino acid changes in the medium are different with each type of tissue culture, all cultures examined removed adenine from the medium and liberated small amounts of material thought to be hypoxanthine.


1993 ◽  
Vol 14 (9) ◽  
pp. 527-529 ◽  
Author(s):  
R. Wesley Farr ◽  
Cheryl Walton

AbstractObjective:To study the ability of a medical waste disposal process using chlorine dioxide to inactivate human immunodeficiency virus type 1 (HIV 1).Design:Stock HIV-1 (HTLV-IIIB strain) was treated with chlorine dioxide under the following settings: cell culture medium alone, culture medium with 25% blood, culture medium with medical supplies treated by the Condor machine (Winfield Environmental Corp., Escondido, CA). MT-2 cells in 96-well tissue culture plates were inoculated with serial tenfold dilutions of treated and untreated HIV-1. Cytopathic effect was read on day five, and the TCID50 (50% tissue culture infectious dose) was calculated.Results:Treatment of HIV-1 with chlorine dioxide in culture medium alone resulted in a 5.25 log10 reduction in TCID50. Treatment of HIV-1 with chlorine dioxide in the presence of 25% blood caused a 6.25 log10 reduction in HIV-1 infectivity Treatment of HIV-1 with chlorine dioxide in the presence of medical supplies treated in the Condor machine resulted in a 4.75 log10 reduction in HIV infectivity.Conclusions:Chlorine dioxide inactivated HIV-1 in vitro. Chlorine dioxide inactivated HIV-1 in the presence of blood and in the presence of medical supplies under conditions that simulated the conditions existing in the Condor machine.


2000 ◽  
Vol 74 (3) ◽  
pp. 203-208 ◽  
Author(s):  
K. Buchmann ◽  
C.V. Nielsen ◽  
J. Bresciani

AbstractSkin responses of fish to various parasites have been shown to involve various immunologically competent cells producing factors which guide the reactions of epithelial cells. However, the present study has demonstrated that a monoculture of epithelial cells has the ability to encapsulate and partially degrade ectoparasites without involvement of leukocytes. The ectoparasitic monogeneanGyrodactylus derjavini was kept on a monolayer of Epithelioma Papulosum Cyprini (EPC) cells in 24-well multidishes supplied with tissue culture medium. Gyrodactylus derjavini did not reproduce but survived an incubation period of up to139 h in the system. Due to sterile conditions, dead gyrodactylids were not subjected to microbial degradation and remained intact for several weeks. However, at 40 days G. derjavini was overgrown by EPC-cells and became partly degraded during the following 15 days. Analysis of enzyme reactivity in EPC-cells showed reactions for ten enzymes including esterases, amidases, phosphatases and phosphohydrolases. No marked differences for the ten enzymes between cell cultures with and without the ectoparasites were found but it cannot be excluded that some of these enzymes took part in parasite degradation. The study showed the in vitro capability of epithelial cells to interact, encapsulate and degrade G. derjavini without the involvement of leukocytes. This response probably is non-specific and will not exclude that various immunocompetent cells and their products normally optimize and accelerate elimination of invading parasites in vivo.


1952 ◽  
Vol 96 (2) ◽  
pp. 137-150 ◽  
Author(s):  
Emanuel Suter

A technique has been described for the cultivation in vitro of normal mononuclear cells on glass slides in a liquid medium. Under these conditions the monocytes transformed into macrophages which proliferated as in ordinary tissue culture. These cultures of monocytes could be infected with tubercle bacilli. The numbers of stainable tubercle bacilli within the monocytes increased steadily in cultures infected with virulent or attenuated strains. Evidence is given to support the view that this increase in numbers of bacilli was due to intracellular multiplication. There was no evidence of intracellular bacillary multiplication in cultures infected with an avirulent strain. Tubercle bacilli multiplying within phagocytes in vitro exert a damaging effect upon the host cells. The damage was most obvious in cells infected with a virulent strain. Tubercle bacilli within phagocytes were protected against the bacteriostatic effect of streptomycin added in a concentration of 5 γ per ml. of culture medium. This permitted the use of streptomycin in infected cultures to prevent extracellular multiplication of the bacilli.


2018 ◽  
Vol 45 (No. 2) ◽  
pp. 83-91
Author(s):  
Anber Mahmoud Ahmed Hassanein ◽  
Inas Mohamed Ali Mahmoud

In vitro propagation of Rosa hybrida, L. cv. ‘Eiffel Tower’ was improved by the addition of thidiazuron (TDZ) and silver nitrate (AgNo<sub>3</sub>) to the culture medium. The combination of auxin and cytokinins was indispensable for inducing response from leaf discs. Maintaining cultures under dark was better than light for callus formation and quality. The source of explants was vital in the regeneration process wherein situ explants produced callus while, in vitro explants regenerated somatic embryos and shoots. Gibberellic acid (GA<sub>3</sub>) had a favorable effect where in vitro explants showed somatic embryogenesis with no shoots on media containing TDZ however, 37% of explants regenerated shoots directly on medium containing GA<sub>3</sub>. The presence of benzyl adenine (BA) was essential for shoot elongation, and indole butyric acid (IBA) was better than indole acetic acid (IAA) for rooting. The optimum conditions produced rooted plants from leaf discs within ten weeks. The reported results clarify factors controlling in vitro regeneration of R. hybrida, and provide a rapid protocol allowing further improvements of rose. 


1986 ◽  
Vol 112 (2) ◽  
pp. 271-277 ◽  
Author(s):  
Mervi Julkunen

Abstract. Human decidua was found to synthesize and secrete placental protein 14 (PP14). The presence of PP14 in tissue explants of decidua, foetal membranes and placenta from term pregnancy was demonstrated by radioimmunoassay. The PP14 content in decidua (1300 ±410 ng/100 mg tissue) was higher than in chorion (570 ± 120 ng/100 mg; P < 0.01), amnion (240 ± 100 ng/100 mg; P < 0.001) or placenta (300 ± 130 ng/100 mg; P< 0.001). Three to 36 times more PP14 was released into culture medium by decidual explants compared with the other tissues, and cycloheximide decreased this release by 39%. Placental tissues released hardly any PP14. Decidual synthesis of PP14 was demonstrated by incorporation of [35S]methionine into immunoprecipitable PP14 in tissue culture.


1993 ◽  
Vol 5 (4) ◽  
pp. 405 ◽  
Author(s):  
ZF Du ◽  
RG Wales

The effects of EDTA and the presence of glucose and glutamine in CZB medium on the development of mouse zygotes of different genotype were investigated. Although 30-80% of zygotes (depending on the cross) passed the 2-cell stage in EDTA-free medium, the addition of a low concentration of EDTA was necessary in these experiments to obtain blastocysts in culture. In reciprocal crosses between outbred (Qs), inbred (DBA/2) and hybrid (B10D2F1) stock, there was evidence of a strong influence of the maternal genome on zygote development, with those from B10D2F1 females performing best irrespective of sire. A paternal influence on development was also evident but the most successful sire varied with the genotype of female used and reciprocal crosses differed greatly in the ability of the resultant zygote to develop in culture. For zygotes recovered from Qs females, CZB medium containing glucose and glutamine supported development to the blastocyst stage better than did medium devoid of these substrates. Tests with embryos from B10D2F1 females indicated that the presence of glucose for the whole or for part of the incubation period stimulated blastocyst development. However, the addition of glutamine to the medium in these tests had no significant effect on the development of blastocysts.


1965 ◽  
Vol 43 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Esther W. Yamada

Increases in the specific activities of undine and deoxyuridine phosphorylases of slices of regenerating rat liver were found 4 hours after incubation in tissue-culture medium containing uridine or 6-azauridine. These increases were not found when the tissue-culture medium contained either 8-azaguanine or puromycin, or when it lacked amino acids. Although both uridine and 6-azauridine were more effective in increasing the specific activity of uridine phosphorylase than that of deoxyuridine phosphorylase, azauridine was more effective than uridine in increasing the specific activities of both enzymes.In time studies, in which slices of regenerating rat liver were incubated in tissue-culture medium containing optimal concentrations of uridine, the specific activities of the two enzymes reached maximum levels at 3–4 hours. Puromycin prevented these increases.


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