Rapid Chromosome Preparations from Solid Tissues of Fishes

1977 ◽  
Vol 34 (2) ◽  
pp. 266-269 ◽  
Author(s):  
Andrew D. Kligerman ◽  
Stephen E. Bloom

A technique is described for obtaining well-spread metaphases from solid tissues of fishes without the use of methodologies that rely on tissue grinders, centrifuges, digestive enzymes, or tissue culture. This procedure involves the formation of a cell suspension from acetic alcohol fixed tissues using 50% acetic acid. The suspension is applied to a warm (50 °C) slide using a micropipette.Solid tissue preparations may be stained by any of the conventional dyes or treated to reveal Q-bands, C-bands, and nucleolar organizers. Large numbers of slides offish chromosomes can be made easily and rapidly using this procedure.

2008 ◽  
Vol 5 (4) ◽  
pp. 529-540 ◽  
Author(s):  
Clara Mata ◽  
Ellen K. Longmire ◽  
David H. McKenna ◽  
Katie K. Glass ◽  
Allison Hubel

1950 ◽  
Vol 34 (2) ◽  
pp. 211-224 ◽  
Author(s):  
E. S. Guzman Barron ◽  
Maria Isabel Ardao ◽  
Marion Hearon

The rate of the aerobic metabolism of pyruvic acid by bakers' yeast cells is determined mainly by the amount of undissociated acid present. As a consequence, the greatest rate of oxidation was observed at pH 2.8. Oxidation, at a slow rate, started at pH 1.08; at pH 9.4 there was no oxidation at all. The anaerobic metabolism, only a fraction of the aerobic, was observed only in acid solutions. There was none at pH values higher than 3. Pyruvic acid in the presence of oxygen was oxidized directly to acetic acid; in the absence of oxygen it was metabolized mainly by dismutation to lactic and acetic acids, and CO2. Acetic acid formation was demonstrated on oxidation of pyruvic acid at pH 1.91, and on addition of fluoroacetic acid. Succinic acid formation was shown by addition of malonic acid. These metabolic pathways in a cell so rich in carboxylase may be explained by the arrangement of enzymes within the cell, so that carboxylase is at the center, while pyruvic acid oxidase is located at the periphery. Succinic and citric acids were oxidized only in acid solutions up to pH 4. Malic and α-ketoglutaric acids were not oxidized, undoubtedly because of lack of penetration.


1976 ◽  
Vol 24 (1) ◽  
pp. 11-15 ◽  
Author(s):  
R C Wolley ◽  
H M Dembitzer ◽  
F Herz ◽  
K Schreiber ◽  
L G Koss

A simple and reliable method of determining the degree of dispersion of a cell suspension has been developed using the Perkin-Elmer Uni-Smear Spinner. Optimum conditions regarding rate and duration of spin, etc., were first ascertained using dispersed cell cultures including human cervical cancer cells as well as gynecologic samples. After spinning, single cells in suspension appeared as isolated cells on the slides. Cell aggregates, on the other hand, remained together. Therefore, the distribution of cells in various sized aggregates could be easily quantitated and the slides retained for future review. This method was used to evaluate the dispersing effects of trypsin, ethylenediaminetetraacetate and and syringing human on human gynecology samples obtained by routine cervical scrapes. None of the dispersion methods has, so far, produced an adequate monodispersed cell suspension without unacceptable cell loss.


2014 ◽  
Vol 9 (12) ◽  
pp. 1182-1195
Author(s):  
Samar Naseer ◽  
Tariq Mahmood

AbstractThe present study was designed to analyze genetically somaclonal variants using biochemical and molecular markers. Efficient tissue culture protocol for Solanum melongena L. cv. Nirrala was developed. Maximum callus induction (100%) was observed for Murashige and Skoog (MS) media supplemented with 2.0 mg L−1 naphthalene acetic acid +0.5 mg L−1 6-benzylaminopurine; and nodal explants gave best callusing response (88.8%) as compared to internodes (88.3%) and leaves (87.7%). The best shooting was induced on nodal and internodal callus in the presence of 2.0 mg L−1 6-benzylaminopurine. Total soluble protein content of callus and regenerated variant plants was estimated for biochemical analysis, and largest amount of soluble protein was found in callus (6.54 mg g−1 fresh tissue) followed by variant plant grown on 2.0 mg L−1 6-benzylaminopurine (5.96 mg g−1 fresh tissue). Random amplification of polymorphic DNA technique was done with five decamer primers (OPC1-OPC5) and maximum polymorphism was detected by OPC 2 (26.99%) among all samples, whereas nodal callus on media containing 1.0 mg L−1 naphthalene acetic acid +1.0 mg L−1 6-benzylaminopurine showed highest polymorphism producing 22 bands, out of which 8 bands were polymorphic. The study shows that this marker system can provide better evaluation of genetic variation induced by tissue culture.


1961 ◽  
Vol 9 (2) ◽  
pp. 369-381 ◽  
Author(s):  
D. F. Parsons ◽  
M. A. Bender ◽  
E. B. Darden ◽  
Guthrie T. Pratt ◽  
D. L. Lindsley

The X5563 tumor has been grown in tissue culture. Cells similar to those of the original tumor migrated from the explant and attached to the glass walls of the culture vessels. Electron microscopy showed that large numbers of particles, similar in morphology to virus particles, were associated with these cells after 7 days of culture. The two principal types of particles found in the tumor in vivo appear to be present in vitro. Many more of these particles, however, were larger and showed a more complex structure. Whereas the particles were mainly localized inside endoplasmic reticulum or the Golgi zone in the tumors in vivo, in the tissue culture the majority of the particles were associated with the plasma membrane and were found outside of the cells. The relation of the particles to the granular body is discussed as well as a possible relation to the mammary tumor agent.


1962 ◽  
Vol 3 (1) ◽  
pp. 24-50 ◽  
Author(s):  
I. Gibson ◽  
G. H. Beale ◽  
E. C. R Reeve

1. Replacement of the dominant genes M1 and M2 in Paramecium aurelia, stock 540 (syngen/variety 1), results in loss of ability to maintain mu particles and manifestation of mate-killing after a delay of eight to fifteen fissions in most cells. The change, when it does occur, is relatively abrupt, extending over less than the space of one inter-fission period.2. The delay between change of genotype and loss of mu particles is interpreted as being due to presence in the initial cytoplasm of some thousand ‘metagons’, which are non-replicating gene derivatives having the physiological activity of the corresponding genes. During successive fissions of paramecia deprived of M1 and M2 the metagons are passively distributed amongst the progeny, until virtually all animals lack them.3. On reaching a stage at which some individuals of genotype m1m1m2m2 contain only a single metagon, the paramecia still contain large numbers of mu particles and are mate-killers. Fission of such animals gives rise to one daughter again with mu particles, and another in which the latter are destroyed during the next inter-fission period.4. By induced cytoplasmic exchange between conjugants, metagons can be transferred from one animal to another via the cytoplasm. Where such transference is into an animal not originally containing mu particles, that animal is converted into a condition in which it favours the maintenance of mu particles and transmits the latter to one or more of its offspring.5. Distribution of metagons amongst progeny of dividing paramecia is not random, due possibly to clumping of the metagons. Induced cytoplasmic exchange seems to break up the clumps.6. Reintroduction of a dominant gene (M2) into a cell recently deprived of the same gene, succeeds—even after fifteen fissions—in re-establishing the ability to support growth of mu particles, provided that the recipient cell contains at least one metagon and one or more mu particles. There is a regular lag of only one fission between introduction of such a dominant gene and its phenotypic manifestation.7. Mathematical formulae are developed for calculating the expected initial number of metagons, the proportions of animals lacking mu particles at each fission following loss of the dominant genes, and the proportions of cells containing 0, 1, 2 …, etc. metagons per cell at any stage. The consequences of one of the possible types of irregular distribution of metagons in dividing paramecia are also considered mathematically.


2014 ◽  
Vol 51 (3) ◽  
pp. 599-612 ◽  
Author(s):  
J. E. Björnberg ◽  
T. Britton ◽  
E. I. Broman ◽  
E. Natan

In this work we introduce a stochastic model for the spread of a virus in a cell population where the virus has two ways of spreading: either by allowing its host cell to live and duplicate, or by multiplying in large numbers within the host cell, causing the host cell to burst and thereby let the virus enter new uninfected cells. The model is a kind of interacting Markov branching process. We focus in particular on the probability that the virus population survives and how this depends on a certain parameter λ which quantifies the ‘aggressiveness’ of the virus. Our main goal is to determine the optimal balance between aggressive growth and long-term success. Our analysis shows that the optimal strategy of the virus (in terms of survival) is obtained when the virus has no effect on the host cell's life cycle, corresponding to λ = 0. This is in agreement with experimental data about real viruses.


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