THE USE OF Cr51 AS A CRITERION OF THYMOCYTE REGENERATION AFTER WHOLE BODY X-IRRADIATION

1965 ◽  
Vol 43 (1) ◽  
pp. 19-27
Author(s):  
P. V. Vittorio ◽  
P. J. Baker ◽  
S. Dziubalo-Blehm
Keyword(s):  
Age Differences ◽  
Whole Body ◽  
Quantitative Criterion ◽  
X Irradiation ◽  
Early Radiation ◽  
Population Ratio ◽  
Time Required ◽  
Different Doses ◽  
In Vitro Uptake

The uptake of Cr51 chromate by thymocytes in vitro after whole body X-irradiation can be used as a sensitive quantitative criterion not only for the evaluation of early radiation damage to these cells but also as a measure of later regeneration. The development of the radiation lesion is characterized by a reduction in the in vitro uptake of Cr51 and the later regeneration of new cells by an increase in Cr51 uptake which is probably due to increased uptake of Cr51 by the young newly formed cells in the damaged tissue which is proliferating in an attempt to repair the damage. The return of the Cr51 uptake to normal is an indication of the time required for the cell population (ratio of young to older cells) to return to normal. By this technique the effect of different doses of X-irradiation on the regeneration of thymocytes has been demonstrated. Treatment with AET before whole body X-irradiation (400 r) indicated that less regeneration was necessary but the recovery time remained unchanged. Age differences produced a change in the extent of repair or regeneration but no change in recovery time.Spermatozoa showed evidence of early damage after whole body X-irradiation. This damage increased with time with no evidence of increased regeneration or repair.

The role of lymphocytes in antibody formation I. Restoration of the haemolysin response in X -irradiated rats with lymphocytes from normal and immunologically tolerant donors

1967 ◽  
Vol 168 (1012) ◽  
pp. 229-243 ◽  
Keyword(s):  
Thoracic Duct ◽  
Immunological Tolerance ◽  
Whole Body ◽  
Sheep Erythrocytes ◽  
X Irradiation ◽  
Additional Support ◽  
Immunological Deficiency ◽  
Donor Lymphocytes

The haemolysin response of rats to an intravenous dose of 10 8 sheep erythrocytes was abolished by pretreatment with 500 rad of whole body X-irradiation. The immunological deficiency in such animals could be corrected equally well by either an injection of thoracic duct cells or by an inoculum consisting almost exclusively of small lymphocytes, obtained in each case from normal (non-immune) rats. The reversal of unresponsiveness depended upon the survival of the donor lymphocytes in the X-irradiated recipients and was not due to a non-specific restoration of the hosts’ own capacity to form antibody. Evidence for this conclusion came from experiments in which the X-irradiated recipients were themselves immunologically tolerant of sheep erythrocytes; additional support came from the inability of lymphocytes from immunologically tolerant donors to restore specific responsiveness in X-irradiated (non-tolerant) recipients. In a proportion of trials the immunological tolerance to sheep erythrocytes exhibited by thoracic duct lymphocytes from tolerant donors could be broken by incubating the cells in vitro before their injection into X-irradiated recipients. This points to the existence of individual tolerant cells in the tolerant populations of lymphocytes. Taken as a whole the experiments suggest strongly that small lymphocytes are the precursors of the cells which produce haemolysin against sheep erythrocytes in the rat.

scholarly journals The effect of whole-body X-irradiation of guinea pigs on liver ribosomes

1968 ◽  
Vol 109 (4) ◽  
pp. 495-505 ◽  
Author(s):  
E. J. Hidvégi ◽  
J. Holland ◽  
Elisabeth Bölöni ◽  
P. Lónai ◽  
F. Antoni ◽  
...  
Keyword(s):  
Amino Acid ◽  
Guinea Pigs ◽  
Sucrose Density Gradient ◽  
Whole Body ◽  
Radiation Doses ◽  
Amino Acid Incorporation ◽  
Acid Incorporation ◽  
X Irradiation ◽  
Liver Ribosomes

1. The size distribution of aggregates of liver ribosomes and their protein-synthesizing ability in vitro were studied shortly after X-irradiation of guinea pigs. 2. Sucrose-density-gradient analysis of the mitochondrial supernatant after treatment with deoxycholate revealed a gradual increase in the number of polysomes, reaching a maximum between 9 and 15 hr. after irradiation. At that period the amount of ribonucleoprotein particles reached a level 25–30% above the control. This finding was confirmed by analytical-ultracentrifugal analysis and electron microscopy. Experiments were conducted to exclude the possibility that the enrichment of polysomes in the irradiated animals had occurred during the isolation procedure. 3. The protein-synthesizing ability of total ribosomal particles was measured in vitro. This showed an increase in amino acid incorporation parallel to the progressive enrichment of polysomes. At radiation doses of up to 1000r. the protein-synthesizing capacity was dependent on the radiation dose: the higher the dose the higher the amino acid incorporation, reaching 40–60% above the control at the period of maximal polysome enrichment. Amino acid incorporation remained at this level after radiation doses of between 1000 and 3000r. The enhanced protein-synthesizing activity was due solely to the increase in the proportion of polysomes, since irradiation was without effect on the activity of single ribosomes. 4. The results of the experiments are discussed in the light of our knowledge of the effect of radiation on protein synthesis.

scholarly journals GAMMA GLOBULIN AND ANTIBODY FORMATION IN VITRO

1967 ◽  
Vol 125 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Vera J. Stecher ◽  
G. Jeanette Thorbecke
Keyword(s):  
Antibody Formation ◽  
Primary Response ◽  
Secondary Response ◽  
Detectable Effect ◽  
Complete Suppression ◽  
Similar Time ◽  
X Irradiation ◽  
Early Radiation

The present studies have shown that the influence of X-irradiation on the secondary antibody response in vitro is remarkably similar to its effect on the primary response in vivo. When sensitized tissue was first irradiated and then reexposed to antigen, the duration of the interval between irradiation and antigen addition determined the degree of inhibition of the secondary response obtained. A delay of 12 hr resulted in stronger inhibition than a delay of 6 hr, and an interval of 24 hr before reexposure to antigen caused complete suppression of antibody production to diphtheria toxoid and almost complete suppression when sheep RBC were used as the antigen. Induction of the secondary response in rabbit lymph node tissue in vitro followed by exposure to X-irradiation, revealed that immediate exposure to irradiation after antigen produced stronger inhibition of the subsequent response than irradiation on days 2–3. Irradiation on day 6 had no detectable effect. The effectiveness of the early radiation is probably due to prevention of the proliferation of the antibody-forming cells. BUDR was found to be effective at similar time periods as X-irradiation, whereas colchicine could still stop antibody formation when added late during the secondary response in vitro. It was noted that lymph nodes from some BSA-sensitized rabbits as late as 18 months after sensitization gave a response indistinguishable from a typical secondary response, even when not reexposed to antigen.

THE USE OF CHROMIUM-51 AS A SENSITIVE QUANTITATIVE CRITERION OF EARLY RADIATION DAMAGE TO RAT THYMOCYTES

1964 ◽  
Vol 42 (4) ◽  
pp. 503-512 ◽  
Author(s):  
J. F. Scaife ◽  
P. V. Vittorio
Keyword(s):  
Cell Death ◽  
Radiation Damage ◽  
Morphological Changes ◽  
Quantitative Criterion ◽  
Early Radiation

The uptake of Cr61-chromate by thymocytes in suspension can be used as a sensitive quantitative criterion for the evaluation of early radiation damage to these cells, often under situations where other methods of assessing cell death such as morphological changes do not yield valid results. The development of a radiation lesion is characterized by a reduction in the uptake of Cr51, which in vitro can be detected 1 hour following irradiation and with doses as low as 25 rads. By means of this technique thymocytes have been shown to be completely protected by anoxia to doses of up to 150 rads, but at higher levels anoxia affords little protection. No protection of thymocytes could be demonstrated in vivo with S,β-aminoethylisothiouronium bromide hydrobromide (AET) or serotonin at 0.72 mmoles per kg. L-Cysteine, cysteamine, and serotonin at 1 mM concentration in vitro showed no protection of thymocytes provided they were removed from the cells immediately subsequent to irradiation.

Evaluation of a new fluoroscopy-based navigation system in the placement of the femoral component in hip resurfacing

2009 ◽  
Vol 224 (4) ◽  
pp. 565-576 ◽  
Author(s):  
S Gravius ◽  
P Belei ◽  
M de la Fuente ◽  
K Radermacher ◽  
T Mumme
Keyword(s):  
Femoral Neck ◽  
Femoral Component ◽  
Navigation System ◽  
Cadaver Study ◽  
Hip Resurfacing ◽  
Whole Body ◽  
Computer Assisted ◽  
Mechanical Alignment ◽  
Time Required

Prosthesis-specific mechanical alignment instruments for the precise and reproducible positioning of the femoral component constitute one of the major improvements in modern hip resurfacing prostheses. However, mechanical failure of the femoral component is mostly attributable to the surgical technique, and in particular to notching of the femoral neck. In order to evaluate a novel computer-assisted fluoroscopy-based planning and navigation system, six DUROMTM hip resurfacing prostheses were implanted into artificial femurs by means of computer-assisted fluoroscopy-based navigation and prosthesis-specific mechanical alignment instruments. Subsequently, the planning and navigation system was tested within the scope of a cadaver study on three fixed whole-body preparations (six femurs). The average difference between planned and actual angle of the prosthesis was 0±0.7° for fluoroscopy-based navigation versus 6.5±7.8° for the in-vitro use of the prosthesis-specific mechanical alignment instruments, and 1±1.4° for fluoroscopic navigation in the cadaver study. The average discrepancy between planned and actual anterior offset was −1.2±1.2 mm versus 0.8±4 mm, and 0.3±2.2 mm in the cadaver study, and the time required for the total of five planning and navigation steps was 17.2±1.5 min versus 14±0.8 min and 20.2±2.5 min respectively. No notching of the femoral neck occurred under fluoroscopy nor under conventional treatment. During in-vitro studies, use of the computer-assisted fluoroscopy-based planning and navigation system resulted in enhanced accuracy compared with conventional prosthesis-specific mechanical alignment instruments. The system has yielded initial promising results within the scope of the cadaver study.

CHANGES IN THE SENSITIVITY OF X-IRRADIATED MICE TO BACTERIAL ENDOTOXIN

1967 ◽  
Vol 45 (3) ◽  
pp. 395-400
Author(s):  
P. V. Vittorio ◽  
E. A. Watkins ◽  
S. Dziubalo-Blehm
Keyword(s):  
Linear Increase ◽  
Bacterial Endotoxin ◽  
Whole Body ◽  
Body Counter ◽  
Whole Body Counter ◽  
X Irradiation ◽  
Different Doses

When endotoxin was injected into mice 4 to 24 hours after X-irradiation the LD50/3 was increased from 500 μg (non-irradiated control) to 715 μg and 825 μg respectively. Administration of different doses of X-irradiation showed that increasing the dose from 200 to 600 R caused a linear increase in the endotoxin LD50 of mice and it was in the order of 100 μg per 200 R. From 800 R to 1400 R there was a decrease in the endotoxin LD50 of mice, but only the 1400-R dose produced a lower LD50 than that in the non-irradiated control. Since whole-body counter studies with 51Cr-labelled endotoxin showed that X-irradiation did not change endotoxin excretion, increased endotoxin LD50 values 4 and 24 hours after X-irradiation were not due to increased rates of endotoxin excretion.

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