Variations in long-term wheat somatic tissue culture

1988 ◽  
Vol 66 (9) ◽  
pp. 1891-1895 ◽  
Author(s):  
J. De Buyser ◽  
C. Hartmann ◽  
Y. Henry ◽  
A. Rode
Keyword(s):  
Somatic Tissue ◽  
Regeneration Ability ◽  
Long Time ◽  
Somatic Tissue Culture ◽  
Chromosomal Changes ◽  
Somatic Embryogenic ◽  
Embryogenic Tissues ◽  
Plant Fertility

Morphological and chromosomal changes were induced among plants regenerated from wheat somatic embryogenic tissues that retain regenerative potential for a long time. An effect of in vitro culture on mitochondrial DNA was also ascertained since variations in mitochrondrial DNA were observed in embryogenic and nonembryogenic genotypes. These variations were detected on restriction patterns. The possible significance of the mtDNA variations in affecting plant fertility and regeneration ability is discussed.

scholarly journals Acquisition of cell migration defines NK cell differentiation from hematopoietic stem cell precursors

2017 ◽  
Vol 28 (25) ◽  
pp. 3573-3581 ◽  
Author(s):  
Barclay J. Lee ◽  
Emily M. Mace
Keyword(s):  
Cell Migration ◽  
Nk Cells ◽  
Nk Cell ◽  
Hematopoietic Stem ◽  
Lineage Differentiation ◽  
Nk Cell Differentiation ◽  
Long Time ◽  
Innate Lymphocytes

Human natural killer (NK) cells are generated from CD34+ precursors and can be differentiated in vitro by coculture with developmentally supportive stromal cells. We have previously described the acquisition of cell migration as a feature of NK cell terminal maturation in this system. Here we perform continuous long-term imaging and tracking of NK cell progenitors undergoing in vitro differentiation. We demonstrate that NK cell precursors can be tracked over long time periods on the order of weeks by utilizing phase-contrast microscopy and show that these cells acquire increasing motility as they mature. Additionally, we observe that NK cells display a more heterogeneous range of migratory behaviors at later stages of development, with the acquisition of complex modes of migration that are associated with terminal maturation. Together these data demonstrate previously unknown migratory behaviors of innate lymphocytes undergoing lineage differentiation revealed by long-term imaging and analysis workflows.

scholarly journals In Vitro Preservation of Potato Plants

2017 ◽  
Vol 76 (1) ◽  
pp. 69-73
Author(s):  
Danuta Strzelczyk-Żyta
Keyword(s):  
In Vitro Culture ◽  
Good Condition ◽  
Early Developmental Stage ◽  
Potato Plants ◽  
Long Term Storage ◽  
In Vitro Preservation ◽  
Long Time ◽  
Early Developmental

Abstract Potato plants free of viruses, bacteria and viroid could be maintained in vitro for a long time. Proper preparation of potato plants for in vitro culture provide its long-term storage in good condition. First step is to establish in vitro culture from young greenhouse grown plants in early developmental stage. Explants are maintained and propagated by nodal subculture on hormone-free Murashige and Skoog (MS) medium at temperature 20-22°C. After rooting, for longer preservation plants are maintained at temperature 8-10°C.

scholarly journals AGENTS USED FOR ENAMEL REMINERALISATION AND REDUCING DENTIN HYPERSENSITIVITY: A COMPREHENSIVE REVIEW

2020 ◽  
Vol 24 (1-2) ◽  
pp. 30-35
Author(s):  
N.V. Yanko
Keyword(s):  
Calcium Phosphate ◽  
Potential Effect ◽  
Deep Penetration ◽  
Dentin Hypersensitivity ◽  
White Spot Lesions ◽  
Long Time ◽  
Fissure Sealing ◽  
The Ideal

ремінералізація, гіперчутливість, десенситизація, емаль, дентинRemineralisation agents not only strengthen enamel resistance, but also can occlude dentine tubules, reducing teeth sensitivity. This article provides an overview of various available agents used for enamel remineralisation and dentin hypersensitivity treatment. Conventional fluorides are used in the form of solutions, varnishes, foam, gels, dentifrices, showing low remineralising and desensitising ability as compared to newer fluoride-content products. Deep fluoridation is an effective method for reducing dentin hypersensitivity for a long time; its remineralising potential is used for white spot lesions treatment, caries prevention, and fissure sealing. Most novel fluoride compounds showed higher remineralising and desensitising abilities as compared to conventional fluorides. Deep penetration fluoridation is an effective method for remineralisation and reducing dentin hypersensitivity in long time. Despite of the fact that calcium phosphate systems have demonstrated a benefit over conventional fluorides in remineralisation their desensitising ability was not confirmed by various studies. The use of bioactive glass in remineralisation and desensitisation is quite promising, but further researches need to be undertaken to prove its efficacy. «Curodont» and synthetic nanohydroxyapatite from biomimetic systems showed good results in the above-mentioned treatments, but more researches are required to confirm their clinical efficacy. There is no doubt that iontophoresis with calcium and fluoride substances is still the most effective method in the office remineralisation, however, its potential effect in desensitisation has to be better evaluated. Efficacy of different kinds of lasers alone or in combination with a remineralisation agent has been confirmed mostly in vitro studies, therefore, there is a lack of clinical trials to prove their benefit. In latter studies, dentin sealants and desensitisers occluded dentin tubules were superior to conventional fluorides and synthetic nanohydroxyapatites. Simultaneously, the data about calcium phosphate and deep penetration fluoridation efficacy over such desensitisers as dentin sealants and nerve sensitivity inhibitors are controversial and indicate that additional studies are required to deepen our knowledge of the insufficiently explored area of reducing dentin hypesensitivity. In spite of the new advances, the ideal treatment modality for remineralisation does not exist. Within last decades, dentistry has made significant steps towards the elusive goal of enamel remineralisation and dentin desensitisation, but more long-term сlinical controlled studies are needed to confirm and quantify these findings, as well as to identify additional factors that can potentiate these processes.

scholarly journals An In-Silico Corrosion Model for Biomedical Applications for Coupling With In-Vitro Biocompatibility Tests for Estimation of Long-Term Effects

2021 ◽  
Vol 9 ◽  
Author(s):  
Tijana Šušteršič ◽  
Gorkem Muttalip Simsek ◽  
Guney Guven Yapici ◽  
Milica Nikolić ◽  
Radun Vulović ◽  
...  
Keyword(s):  
In Silico ◽  
Long Term Effects ◽  
Ion Release ◽  
Implant Surface ◽  
In Vitro Biocompatibility ◽  
Metallic Implants ◽  
Long Time ◽  
Corrosion Mechanisms

The release of metal particles and ions due to wear and corrosion is one of the main underlying reasons for the long-term complications of implantable metallic implants. The rather short-term focus of the established in-vitro biocompatibility tests cannot take into account such effects. Corrosion behavior of metallic implants mostly investigated in in-vitro body-like environments for long time periods and their coupling with long-term in-vitro experiments are not practical. Mathematical modeling and modeling the corrosion mechanisms of metals and alloys is receiving a considerable attention to make predictions in particular for long term applications by decreasing the required experimental duration. By using such in-silico approaches, the corrosion conditions for later stages can be mimicked immediately in in-vitro experiments. For this end, we have developed a mathematical model for multi-pit corrosion based on Cellular Automata (CA). The model consists of two sub-models, corrosion initialization and corrosion progression, each driven by a set of rules. The model takes into account several environmental factors (pH, temperature, potential difference, etc.), as well as stochastic component, present in phenomena such as corrosion. The selection of NiTi was based on the risk of Ni release from the implant surface as it leads to immune reactions. We have also performed experiments with Nickel Titanium (NiTi) shape memory alloys. The images both from simulation and experiments can be analyzed using a set of statistical methods, also investigated in this paper (mean corrosion, standard deviation, entropy etc.). For more widespread implementation, both simulation model, as well as analysis of output images are implemented as a web tool. Described methodology could be applied to any metal provided that the parameters for the model are available. Such tool can help biomedical researchers to test their new metallic implant systems at different time points with respect to ion release and corrosion and couple the obtained information directly with in-vitro tests.

RETARDED BIOSYNTHESIS OF THYROGLOBULIN SUBUNITS AND THEIR POLYMERIZATION IN VITRO AFTER SUPPRESSION OF TSH SECRETION IN RATS BY CHRONIC ADMINISTRATION OF EXCESS THYROXINE IN THE FORM OF IODINATED CASEIN

1978 ◽  
Vol 89 (1) ◽  
pp. 108-121
Author(s):  
J. Sinadinović ◽  
M. Krainčanić ◽  
G. Kostić ◽  
M. Jovanović
Keyword(s):  
Chronic Administration ◽  
Thyroxine Treatment ◽  
Time Period ◽  
Tsh Secretion ◽  
Long Time ◽  
Pre Treatment ◽  
Reduced Rate

ABSTRACT The effects of short- and long-term (from 3 days to 28 weeks) administration of excess thyroxine in the form of the iodinated casein "Protamone" (0.2%) to rats on the content of soluble thyroid iodoproteins and on biosynthesis and polymerization of thyroid proteins in vitro were investigated. The concentration of soluble iodoproteins significantly increased (40–80%) up to 2 weeks of treatment, and after that remained at the same level. 27S iodoprotein markedly increased during thyroxine treatment. The content of DNA in the gland and the thyroid weight were a little lower in the treated rats than in the control. The incorporation rate of [14C]leucine into soluble and microsome-bound proteins in vitro was markedly reduced in the treated animals (30–80 % of control). Thyroxine pre-treatment of rats induced retarded synthesis of thyroglobulin and its subunits in vitro. The inhibition of the synthesis of thyroid proteins in vitro and the incrrease in the soluble iodopritein content in the gland in vivo was not correlated with the duration of thyroxine treatment. The immobilization of pre-formed thyroglobulin in the follicle lumen for a long time period is probably an important factor in the enlarged conversion of thyroglobulin into 27S iodoprotein. In conclusion, the long-term suppression of endogenous TSH secretion by administration of thyroxine results in an accumulation of iodoproteins in the thyroid and a reduced rate of synthesis of iodoproteins; after 2 weeks a steady state is reached both with regard to iodoprotein accumulation and synthesis. Finally, the results obtained suggest that the thyroid-pituitary axis becomes adapted to chronic administration of excess thyroxine.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Human thymic epithelial cells maintain long-term survival of clonogenic myeloid and erythroid progenitor cells in vitro

2000 ◽  
Vol 111 (1) ◽  
pp. 363-370 ◽  
Author(s):  
Katsuto Takenaka ◽  
Mine Harada ◽  
Tomoaki Fujisaki ◽  
Koji Nagafuji ◽  
Shinichi Mizuno ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Progenitor Cells ◽  
Thymic Epithelial Cells ◽  
Erythroid Progenitor ◽  
Term Survival ◽  
Long Term Survival ◽  
Erythroid Progenitor Cells

Human liver cell cultivation for long-term in vitro toxicity studies in a miniaturized multi-compartment 3D bioreactor system

2011 ◽  
Vol 49 (01) ◽  
Author(s):  
SA Hoffmann ◽  
M Lübberstedt ◽  
U Müller-Vieira ◽  
D Knobeloch ◽  
A Nüssler ◽  
...  
Keyword(s):  
Liver Cell ◽  
Human Liver ◽  
In Vitro Toxicity ◽  
Cell Cultivation ◽  
Toxicity Studies ◽  
Human Liver Cell ◽  
Bioreactor System

Enhancing the power generation of Rhodopseudomonas palustris-based MFC

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1261-1268
Author(s):  
Shu Otani ◽  
Dang-Trang Nguyen ◽  
Kozo Taguchi
Keyword(s):  
Activated Carbon ◽  
Rhodopseudomonas Palustris ◽  
Ozone Treatment ◽  
Maximum Power Density ◽  
On Demand ◽  
Long Time ◽  
Dry Conditions ◽  
Carbon Sheet ◽  
Uv Ozone

In this study, a portable and disposable paper-based microbial fuel cell (MFC) was fabricated. The MFC was powered by Rhodopseudomonas palustris bacteria (R. palustris). An activated carbon sheet-based anode pre-loaded organic matter (starch) and R. palustris was used. By using starch in the anode, R. palustris-loaded on the anode could be preserved for a long time in dry conditions. The MFC could generate electricity on-demand activated by adding water to the anode. The activated carbon sheet anode was treated by UV-ozone treatment to remove impurities and to improve its hydrophilicity before being loaded with R. palustris. The developed MFC could generate the maximum power density of 0.9 μW/cm2 and could be preserved for long-term usage with little performance degradation (10% after four weeks).

Somatic Embryogenesis and In vitro Plant Regeneration in Vigna trilobata (L.) Verd. - A Potential Pasture Legume

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat
Keyword(s):  
Somatic Embryogenesis ◽  
Growth Regulators ◽  
Somatic Embryos ◽  
Basal Medium ◽  
Long Term Study ◽  
Continuous Application ◽  
First Time ◽  
Pasture Legume

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)

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