Cytoplasmic DNA-Containing Bodies and the Response of Amoebae to Dimidium Bromide

1969 ◽  
Vol 5 (1) ◽  
pp. 57-63
Author(s):  
SHIRLEY E. HAWKINS ◽  
LESLEY R.WILLIS
Keyword(s):  
Acridine Orange ◽  
Quantitative Difference ◽  
Amoeba Proteus ◽  
Fluorescence Microscope ◽  
Dna And Rna ◽  
Cytoplasmic Bodies ◽  
Cytoplasmic Dna ◽  
The Difference

The growth of Amoeba proteus (T1P) and Amoeba discoides (T1) in the trypanocidal phenanthridlnium, dimidium bromide was examined. At concentrations of drug between 2 and 4 µg/ml, A. proteus divided twice before inhibition and death. A. discoides was able to undergo an additional cycle of division before death. At other concentrations there were no differences in their response. Heterotransfers between these strains resembled A. discoides, both dividing three times before death. Examination of clones derived from the micro-injection of small quantities of A. discoides cytoplasm into A. proteus showed that the ability to divide additionally in dimidium bromide could be transferred. Some other strains of A. proteus (DP, T4P) also resembled A. discoides in their response. Cells of all the strains used were treated with acridine orange and observed under the fluorescence microscope for the presence of DNA- and RNA-containing cytoplasmic ‘bodies’. All strains able to undergo an additional division cycle also possessed cytoplasmic DNAcontaining bodies. The converse was not 100%, but this may be due to a quantitative difference in the number of DNA-containing bodies in the cytoplasm. It is proposed that the difference in response to dimidium bromide observed in A. proteus and A. discoides may be associated with the presence of DNA- and RNA-containing bodies in the cytoplasm of A. discoides.

scholarly journals CYTOPLASMIC DNA SYNTHESIS IN AMOEBA PROTEUS

1962 ◽  
Vol 15 (3) ◽  
pp. 535-540 ◽  
Author(s):  
M. Rabinovitch ◽  
W. Plaut
Keyword(s):  
Nucleic Acid ◽  
Dna Synthesis ◽  
Acridine Orange ◽  
Particle Number ◽  
Amoeba Proteus ◽  
Acridine Orange Staining ◽  
Particle Population ◽  
Cell Age ◽  
Cytoplasmic Dna ◽  
Number Of Particles

Nucleic acid-containing particles in the cytoplasm of Amoeba proteus (cf. reference 1) were counted after acridine orange staining. The number of particles per ameba was found to be correlated with cell age and size. Fresh daughters had a mean particle number of 5400, whereas predivision amebae contained around 11,000 particles. Amebae from two other strains contained similar particles. The particles were found to be clustered in fasted cells and redispersed after feeding. A marked increase in the particle population was noted in anucleate fragments. These results, together with those previously presented, suggest that the particles multiply intracellularly. Their nature and their relationship to previous work on nucleic acid labeling in Amoeba are discussed.

scholarly journals CYTOPLASMIC DNA SYNTHESIS IN AMOEBA PROTEUS

1962 ◽  
Vol 15 (3) ◽  
pp. 525-534 ◽  
Author(s):  
M. Rabinovitch ◽  
W. Plaut
Keyword(s):  
Dna Synthesis ◽  
Tritiated Thymidine ◽  
Amoeba Proteus ◽  
Living Cells ◽  
Large Numbers ◽  
Cytoplasmic Dna ◽  
Basic Dyes ◽  
Nuclease Digestion ◽  
High Degree ◽  
Very High

The incorporation of tritiated thymidine in Amoeba proteus was reinvestigated in order to see if it could be associated with microscopically detectable structures. Staining experiments with basic dyes, including the fluorochrome acridine orange, revealed the presence of large numbers of 0.3 to 0.5 µ particles in the cytoplasm of all cells studied. The effect of nuclease digestion on the dye affinity of the particles suggests that they contain DNA as well as RNA. Centrifugation of living cells at 10,000 g leads to the sedimentation of the particles in the centrifugal third of the ameba near the nucleus. Analysis of centrifuged cells which had been incubated with H3-thymidine showed a very high degree of correlation between the location of the nucleic acid-containing granules and that of acid-insoluble, deoxyribonuclease-sensitive labeled molecules and leads to the conclusion that cytoplasmic DNA synthesis in Amoeba proteus occurs in association with these particles.

ON THE ISOLATION AND GROWTH OF INDIVIDUAL MICROBIAL CELLS FROM SOIL

1962 ◽  
Vol 8 (1) ◽  
pp. 115-119 ◽  
Author(s):  
L. E. Casida Jr.
Keyword(s):  
Acridine Orange ◽  
Morphological Characteristics ◽  
Fluorescence Microscope ◽  
Microbial Cells

A technique is described for the direct isolation and growth of individual vitally stained microorganisms which have been observed in soil preparations. Soil is stained with acridine orange and mounted on agar so that individual cells can be picked from the soil with a micromanipulation tool while the organism is being viewed with an ultraviolet fluorescence microscope. These cells are then grown in nutritive media to provide cultures for identification of the organisms and for studies of their nutritional, physiological, and morphological characteristics.

scholarly journals Different sensitivity of chromatin to acid denaturation in quiescent and cycling cells as revealed by flow cytometry.

1979 ◽  
Vol 27 (1) ◽  
pp. 478-485 ◽  
Author(s):  
Z Darzynkiewicz ◽  
F Traganos ◽  
M Andreeff ◽  
T Sharpless ◽  
M R Melamed
Keyword(s):  
Acridine Orange ◽  
Condensed Chromatin ◽  
Metaphase Chromosomes ◽  
Quiescent Cells ◽  
Acid Denaturation ◽  
Interphase Cells ◽  
The Difference ◽  
Cell Subpopulations ◽  
G1 Cells ◽  
Dna Complex

The properties of DNA in situ as reflected by its staining with acridine orange are different in quiescent nonstimulated lymphocytes as compared with interphase lymphocytes that have entered the cell cycle after stimulation by mitogens. The difference is seen after cell treatment with buffers at pH 1.5 (1.3-1.9 range) followed by staining with acridine orange at pH 2.6 (2.3-2.9). Under these conditions the red metachromatic fluorescence of the acridine orange-DNA complex is higher in quiescent cells than in the cycling lymphocytes while the orthochromatic green fluorescence is higher in the cycling, interphase cells. The results suggest that DNA in condensed chromatin of quiescent lymphocytes (as in metaphase chromosomes) is more sensitive to acid-denaturation than DNA in dispersed chromatin of the cycling interphase cells. The phenomenon is used for flow cytometric differentiation between G0 and G1 cells and between G2 and M cells. In contrast to normal lymphocytes the method applied to neoplastic cells indicates the presence of cell subpopulations with condensed chromatin but with DNA content characteristic not only of G1 but also of S and G2 cells. The possibility that these cells represent quiescent (resting) subpopulations, arrested in G1, S and/or G2, is discussed.

Ergoloids and Ischaemic Strokes; Efficacy and Mechanism of Action

1995 ◽  
Vol 23 (3) ◽  
pp. 154-166 ◽  
Author(s):  
O Elwan ◽  
AA Helmy ◽  
ME Tamawy ◽  
MA Naseer ◽  
IE Banhawy ◽  
...  
Keyword(s):  
Short Term Memory ◽  
Randomized Study ◽  
Quantitative Difference ◽  
Short Term ◽  
Limb Function ◽  
Double Blind ◽  
The Difference ◽  
Ischaemic Insult ◽  
Assessment Geriatric ◽  
Computerized Electroencephalography

In this double-blind, randomized study the efficacy of the ergoloid compounds, co-dergocrine mesylate and nicergoline, in the rehabilitation of patients with ischaemic stroke was investigated. A group of 30 patients was treated daily with 60 mg nicergoline, orally, and a second group of 27 patients was given 1.8 – 6 mg co-dergocrine mesylate, orally or intramuscularly, daily (depending on the time since the initial ischaemic insult) for 6 months. Outcome measures included: motoricity index (limb function); Sandoz Clinical Assessment Geriatric (SCAG) scale; psychometric tests to assess functions such as attention, psychomotor performance, perception and sensory and short-term memory; conventional and computerized electroencephalography; and P300 and reaction time measures. The results showed improvements in some aspects such as limb function ( P < 0.05), SCAG score ( P < 0.01) and some electrophysiological parameters ( P < 0.01) after treatment with both drugs. Though statistically significant most of the changes were not large. The efficacy of both drugs was qualitatively similar. The quantitative difference in some aspects in favour of nicergoline could be attributed to differences in the mechanisms of action of the two drugs, although it is also possible that the difference may reflect the dosages used. Nootropic drugs may induce a condition that facilitates the effects of cognitive training.

scholarly journals Histoplasma capsulatum modulates the acidification of phagolysosomes.

1993 ◽  
Vol 177 (6) ◽  
pp. 1605-1611 ◽  
Author(s):  
L G Eissenberg ◽  
W E Goldman ◽  
P H Schlesinger
Keyword(s):  
Drug Delivery ◽  
Acridine Orange ◽  
Antigen Processing ◽  
Lysosomal Enzymes ◽  
Histoplasma Capsulatum ◽  
Hydrolytic Enzymes ◽  
Fluorescein Isothiocyanate ◽  
Neutral Ph ◽  
Microbial Survival ◽  
The Difference

The phagolysosome is perhaps the most effective antimicrobial site within macrophages due both to its acidity and to its variety of hydrolytic enzymes. Few species of pathogens survive and multiply in these vesicles. However, one strategy for microbial survival would be to induce a higher pH within these organelles, thus interfering with the activity of many lysosomal enzymes. Altering the intravesicular milieu might also profoundly influence antigen processing, antimicrobial drug delivery, and drug activity. Here we report the first example of an organism proliferating within phagolysosomes that maintain a relatively neutral pH for a sustained period of time. We inoculated P388D1 macrophages with fluorescein isothiocyanate (FITC)-labeled Histoplasma capsulatum or zymosan. Using the ratio of fluorescence excitations at 495 and 450 nm, we determined that vesicles containing either virulent or avirulent FITC-labeled H. capsulatum yeasts had a pH one to two units higher than vesicles containing either zymosan or methanol-killed H. capsulatum. The difference in pH remained stable for at least 5.5 h postinoculation. Longer-term studies using cells preincubated with acridine orange indicated that phagolysosomes containing live Histoplasma continued to maintain a relatively neutral pH for at least 30 h. Many agents raise the pH of multiple vesicles within the same cell. In contrast, H. capsulatum affects only the phagolysosome in which it is located; during coinoculation of cells with unlabeled Histoplasma and labeled zymosan, organelles containing zymosan still acidified normally. Similarly, unlabeled zymosan had no influence on the elevated pH of vesicles housing labeled Histoplasma. Thus, zymosan and Histoplasma were segregated into separate phagolysosomes that responded independently to their phagocytized contents. This localized effect might reflect an intrinsic difference between phagosomes housing the two particle types, active buffering by the microbe, or altered ion transport across the phagolysosomal membrane such that acidification is inhibited.

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